Andre Eckardt - Academia.edu (original) (raw)

Papers by Andre Eckardt

Journal of Craniofacial Surgery, 2012

Over the past years, computer-assisted surgery has gained more importance in craniomaxillofacial ... more Over the past years, computer-assisted surgery has gained more importance in craniomaxillofacial surgery, especially in primary and secondary treatment of head and neck malignancies. The basis for oncologic treatment of the head and neck region requires detailed planning using computed tomography, cone-beam computed tomography, or magnetic resonance imaging in combination with computer-assisted, infrared-based navigation system. These techniques allow a preplanned image-guided path to the tumor region for taking biopsies, resection, or reconstruction. The aim of this work was to show the advances and technical benefits for tumor surgery in a daily clinical routine from the view of the craniomaxillofacial surgeon. The target of our working group was to develop and clinically evaluate a novel three-dimensional planning and navigation software solution for treatment of craniofacial tumors. This work was carried out on 5 categories for oncologic surgical procedures in which computer-assisted surgery was applied from 2005 to 2011: preplanned trajectorial-guided tumor biopsy, intraoperative imageYcontrolled tumor resection, tumor mapping, reconstruction after tumor surgery (true to original), and oral rehabilitation (backward planning). Successful preoperative planning, import of image data suitable for navigation, and intraoperative precise infraredbased navigation were obtained for all 5 categories without any complications. Image-guided navigation technique for head and neck oncologic surgery provides a precise, safe surgical method with real-time excellent anatomic orientation. Regarding the advantages of computerassisted surgery, this technique will play a major part in craniofacial reconstructive surgery and will address widespread general methodologic solutions that are of great interest in multidisciplinary oncologic treatment.

Craniomaxillofacial Trauma & Reconstruction, 2010

Reconstruction of mandibular defects following tumor resection in infants is a particular challen... more Reconstruction of mandibular defects following tumor resection in infants is a particular challenge. Although autogenous rib grafts have no relevance in the restoration of mandibular bone defects occurring after ablative tumor surgery due to limited bone stock and the availability of other donor areas, they are a useful surgical alternative following tumor surgery in infants. We here report on a 2, 5, 8, and 15-year follow-up of four children who were diagnosed with benign tumors of the mandible with osseous destruction at the age of 4, 6, 15, and 18 months, respectively. Histologic diagnoses were melanotic neuroectodermal tumor ( n=2), hemangioendothelioma of the mandible ( n=1), and ameloblastoma ( n=1). Following continuity resection of the mandible, lateromandibular bone defects were restored using autogenous rib grafts. Both clinical and radiologic follow-up visits were performed for all children to assess growth of the facial skeleton and the mandible. One child was already fu...

Physical Review A, 2018

We derive a theory for Bose condensation in nonequilibrium steady states of bosonic quantum gases... more We derive a theory for Bose condensation in nonequilibrium steady states of bosonic quantum gases that are coupled both to a thermal heat bath and to a pumped reservoir (or gain medium), while suffering from loss. Such a scenario describes photonic many-body systems such as excitonpolariton gases. Our analysis is based on a set of kinetic equations for a gas of noninteracting bosons. By identifying a dimensionless scaling parameter controlling the boson density, we derive a sharp criterion for which system states become selected to host a macroscopic occupation. We show that with increasing pump power, the system generically undergoes a sequence of nonequilibrum phase transitions. At each transition a state either becomes or ceases to be Bose selected (i.e. to host a condensate): The state which first acquires a condensate when the pumping exceeds a threshold is the one with the largest ratio of pumping to loss. This intuitive behavior resembles simple lasing. In the limit of strong pumping, the coupling to the heat bath becomes dominant so that eventually the ground state is selected, corresponding to equilibrium(-like) Bose condensation. For intermediate pumping strengths, several states become selected giving rise to fragmented nonequilibrium Bose condensation. We compare these predictions to experimental results obtained for excitons polaritons in a double-pillar structure [Phys. Rev. Lett. 108, 126403 (2012)] and find good agreement. Our theory, moreover, predicts that the reservoir occupation is clamped at a constant value whenever the system hosts an odd number of Bose condensates.

Craniomaxillofacial Trauma & Reconstruction Open, 2020

Metastasis to the mandibular condyle and cervical spine in oncologic patients is rare, and clinic... more Metastasis to the mandibular condyle and cervical spine in oncologic patients is rare, and clinicians should therefore be alert if patients present with such suspicious lesions for further clinical and pathological examinations. A 58-year old female patient with uterine cervical cancer initially presented with mild left condylar dysfunction. CT-imaging revealed a progressive osteolytic lesion of the left condyle and at the same time CT-scans revealed an osteolytic lesion of the cervical spine. Further metastatic bone lesions were ruled out. An incisional biopsy of the left condyle revealed metachronous metastasis from the uterine cervical carcinoma. Based on clinical and radiological examinations the patient underwent surgery with total alloplastic replacement of the temporomandibular joint (TMJ) and in a second surgical approach stabilization of the cervical spine. Suspicious symptoms with TMJ dysfunction in conjunction with osteolytic lesions of the maxillofacial skeleton in onco...

British Journal of Cancer, 2007

Despite significant advances in the use of surgery, chemotherapy and radiotherapy to treat squamo... more Despite significant advances in the use of surgery, chemotherapy and radiotherapy to treat squamous cell carcinoma of the head and neck (SCCHN), prognosis has improved little over the past 30 years. There is a clear need for novel, more effective therapies to prevent relapse, control metastases and improve overall survival. Improved understanding of SCCHN disease biology has led to the introduction of molecularly targeted treatment strategies in these cancers. The epidermal growth factor receptor (EGFR) is expressed at much higher levels in SCCHN tumours than in normal epithelial tissue, and EGFR expression correlates with poor prognosis. Therefore, much effort is currently directed toward targeting aberrant EGFR activity (e.g. cell signalling) in SCCHN. This review discusses the efficacy of novel therapies targeting the EGFR (e.g. anti-EGFR antibodies and EGFR tyrosine kinase inhibitors) that are currently tested in SCCHN patients.

Journal of the Korean Association of Oral and Maxillofacial Surgeons, 2013

Reconstruction of oral soft-tissue defects following resection of oral carcinomas can be achieved... more Reconstruction of oral soft-tissue defects following resection of oral carcinomas can be achieved using various techniques including microsurgical tissue transfer. However, there seems to be a role for regional or local flaps. Small to medium-size defects can be functionally reconstructed with the platysma myocutaneous flap as an excellent choice particularly in medically compromised patients not being eligible for free tissue transfer. The present paper reviews the indication, surgical technique, and complications following reconstruction of defects of the oral cavity with the platysma myocutaneous flap.

BMC Cancer, 2014

Background Humans and dogs are affected by squamous cell carcinomas of the oral cavity (OSCC) in ... more Background Humans and dogs are affected by squamous cell carcinomas of the oral cavity (OSCC) in a considerably high frequency. The high mobility group A2 (HMGA2) protein was found to be highly expressed in human OSCC and its expression was suggested to act as a useful predictive and prognostic tool in clinical management of oral carcinomas. Herein the expression of HMGA2 and its sister gene HMGA1 were analysed within human and canine OSCC samples. Additionally, the HMGA negatively regulating miRNAs of the let-7 family as well as the let-7 regulating gene Lin28 were also comparatively analysed. Deregulations of either one of these members could affect the progression of human and canine OSCC. Methods Expression levels of HMGA1, HMGA2, Lin28, let-7a and mir-98 were analysed via relative qPCR in primary human and canine OSCC, thereof derived cell lines and non-neoplastic samples. Additionally, comparative HMGA2 protein expression was analysed by immunohistochemistry. Results In both s...

Head & Neck, 2014

Background-The patterns of regional metastasis in adenoid cystic carcinoma (ACC) of the head and ... more Background-The patterns of regional metastasis in adenoid cystic carcinoma (ACC) of the head and neck and its association with outcome is not established.

Journal of Neurological Surgery Part B: Skull Base, 2013

Objectives To identify independent predictors of outcome in patients with adenoid cystic carcinom... more Objectives To identify independent predictors of outcome in patients with adenoid cystic carcinoma (ACC) of the paranasal sinuses and skull base. Design Meta-analysis of the literature and data from the International ACC Study Group. Setting University-affiliated medical center. Participants The study group consisted of 520 patients, 99 of them from the international cohort. The median follow-up period was 60 months (range, 32 to 100 months). Main Outcome Measures Overall survival (OS) and disease-specific survival (DSS). Results The 5-year OS and DSS of the entire cohort were 62% and 67%, respectively. The local recurrence rate was 36.6%, and the regional recurrence rate was 7%. Distant

World Journal of Surgical Oncology, 2012

Background Cervical metastasis has a tremendous impact on the prognosis in patients with carcinom... more Background Cervical metastasis has a tremendous impact on the prognosis in patients with carcinomas of the head and neck and the frequency of such spread is greater than 20% for most squamous cell carcinomas. With emerging evidence, focus is shifting to conservative neck procedures aimed at achieving good shoulder function without compromising oncologic safety. The purpose of this study was to analyze the pattern of nodal metastasis in patients presenting with squamous cell carcinoma of buccal mucosa. Materials and methods This was a prospective clinical analysis of patients who were histologically diagnosed with squamous cell carcinoma of the buccal cavity and clinically N1 and had not received treatment anywhere else. Patients were analyzed for age and sex distribution, tumor staging, location, and metastasis. Results The incidence of metastatic lymph node in T4 (n=44) was the highest, that is, level I was 100% (44/44), level II was 43.18% (19/44), level III was 15.90% (7/44), and...

World Journal of Surgical Oncology, 2013

Background: Lymphomas of the orbit and orbital adnexae are rare tumors, comprising only 1% of all... more Background: Lymphomas of the orbit and orbital adnexae are rare tumors, comprising only 1% of all non-Hodgkin's lymphoma. The majority of non-Hodgkin's lymphomas of the orbit are extranodal marginal-zone B-cell lymphomas of mucosa-associated lymphoid tissue type. Because of nonspecific clinical signs and symptoms, some diagnostic delay may occur. The purpose of the study was to evaluate the diagnostic approach in orbital lymphomas and to analyze their treatment outcome. Methods: In the period from 2005 to 2012, from a group of 135 patients with tumors of the orbit, we identified 11 patients diagnosed with orbital lymphoma. This patient cohort was reviewed retrospectively. Results: The patient group consisted of 11 patients (seven females, male males) with a median age of 57.7 years (range 42 to 88 years). Orbital swelling, pain and motility impairment were the leading clinical symptoms. Diagnosis was confirmed by surgical biopsy. Depending on the anatomic location of the tumor, a surgical biopsy was taken using a blepharoplasty incision, a lateral orbitotomy or a navigation-guided biopsy. The predominant histology was extranodal non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue type (82%). All patients underwent complete clinical staging. These were clinical stage I EA in seven patients, and stages II EA (n = 2) and III EA (n = 2) in four patients. Patients in stage I EA were treated with radiation therapy alone, with radiation doses between 25 and 40 Gy, and patients with stage II EA received systemic chemotherapy with bendamustin/rituximab. Those two patients diagnosed with diffuse large B-cell lymphoma and mantle cell lymphoma received systemic chemotherapy according to the R-CHOP protocol. Conclusions: Owing to unspecific clinical symptoms, some diagnostic delay may occur in orbital lymphoma. If unspecific orbital symptoms are present, adequate imaging studies followed by early surgical biopsy will contribute to early diagnosis. Once diagnosis is established and staging is complete, radiation therapy is the recommended treatment for stage I EA patients. Systemic chemotherapy is indicated in selected stage II EA patients and in patients with stage III EA disease.

Trials, 2012

Background: The zygoma plays an important role in the facial contour for both cosmetic and functi... more Background: The zygoma plays an important role in the facial contour for both cosmetic and functional reasons; therefore zygomatic bone injuries should be properly diagnosed and adequately treated. Comparison of various surgical approaches and their complications can only be done objectively using outcome measurements which in turn require protocol management and long-term follow up. The preference for open reduction and internal fixation of zygomatic fractures at three points has continued to grow in response to observations of inadequate results from two point and one point fixation techniques. The objectives of this study were to compare the efficacy of zygomatic bone after treatment with ORIF using 2 point fixation and ORIF using 3 point fixation and compare the outcome of two procedures. Methods: 100 patients were randomly divided equally into two groups. In group A, 50 patients were treated by ORIF using two point fixation by miniplates and in group B, 50 patients were treated by ORIF using three point fixation by miniplates. They were evaluated for their complications during and after surgery with their advantages and disadvantages and the difference between the two groups was observed. Results: A total of 100 fractures were sustained. We found that postoperative complication like decreased malar height and vertical dystopia was more common in those patients who were treated by two point fixation than those who were treated with three point fixation. Conclusions: Based on this study open reduction and internal fixation using three point fixation by miniplates is the best available method for the treatment zygomatic bone fractures.

Radiation Oncology, 2011

Background: Preoperative radiotherapy and chemotherapy in patients with head and neck cancer resu... more Background: Preoperative radiotherapy and chemotherapy in patients with head and neck cancer result in changes to the vessels that are used to construct microsurgical anastomoses. The aim of the study was to investigate quantitative changes and HSP70 expression of irradiated neck recipient vessels and transplant vessels used for microsurgical anastomoses. Methods: Of 20 patients included in this study five patients received neoadjuvant chemoradiation, another five received conventional radiotherapy and 10 patients where treated without previous radiotherapy. During surgical procedure, vessel specimens where obtained by the surgeon. Immunhistochemical staining of HSP70 was performed and quantitative measurement and evaluation of HSP70 was carried out.

Radiation Oncology, 2011

The quality of the interdisciplinary interface in oncological treatment between surgery, patholog... more The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient's specific tumor information (invasion to vessels and nerves, non-resectable tumor) to oncologists, radiotherapists and pathologists.

Orphanet Journal of Rare Diseases, 2013

Background Oral sub mucous fibrosis is a rare chronic, progressive, pre malignant collagen disord... more Background Oral sub mucous fibrosis is a rare chronic, progressive, pre malignant collagen disorder of oral mucosa in people of Asian descent characterized by trismus, blanching and stiffness of mucosa, burning sensation in mouth and hypomobility of soft palate and tongue with loss of gustatory sensation. Betel nut chewing is the most common etiological agent. Surgery remains the main stay in severe cases and aims at release of fibrotic bands and resurfacing the raw areas with different options. Reconstruction can be done by using nasolabial flap or radial free forearm flap. The purpose of this study was to compare the mouth opening after the reconstruction with either nasolabial flap or radial free forearm flap. Methods This study was carried out on fifty (50) patients with oral sub mucous fibrosis. Twenty five (25) of these were reconstructed by nasolabial flap and twenty five (25) were reconstructed by radial free forearm flap. At different intervals of their post-operative visit...

Head & face medicine, Jan 9, 2011

A 63 year-old male with a huge odontogenic lesion of sinus maxillaris was treated with computer-a... more A 63 year-old male with a huge odontogenic lesion of sinus maxillaris was treated with computer-assisted surgery. After resection of the odontogenic lesion, the sinus wall was reconstructed with a prebended 3D titanium-mesh using CAD/CAM technique. This work provides a new treatment device for maxillary reconstruction via rapid prototyping procedures.

Head and Neck Pathology, 2013

Caspase 14 is one of the latter discovered members of the caspase enzyme family and, although sha... more Caspase 14 is one of the latter discovered members of the caspase enzyme family and, although sharing sequence homologies with the other caspases, it is not involved in apoptosis. Together with its co-factor filaggrin, it plays an important role in skin barrier formation. It is already known that caspase 14 proteins are reduced during neoplastic dedifferentiation in cervical intraepithelial neoplasms and in invasive cervical carcinomas. Oral squamous carcinoma tissues have not been systematically evaluated for caspase 14 expression yet. Formalin-fixed and paraffin-embedded samples from oral squamous carcinomas (n = 36 tumours from 34 patients), metastases (n = 15) and controls (leukoplakia, n = 10) were analysed by immunohistochemistry. In carcinomas, human papilloma virus (HPV) infection was tested by PCR. Here we demonstrate that, in oral epithelia, caspase 14 is expressed mainly by cells of the intermediate and superficial cell layers while filaggrin is expressed only in keratinising foci in leukoplakia. Caspase 14 and filaggrin are co-localised. In invasive oral carcinomas, reduced expression of caspase 14 was detectable in 47 % of tumours but was not associated with keratinisation, tumour differentiation or HPV infection. Filaggrin was detectable in a subfraction of tumours (56 %) and was restricted to keratinising areas of the carcinomas. In summary, in contrast to cervical carcinomas, partial loss of caspase 14 is not associated with dedifferentiation in neoplastic lesions of the oral mucosa or HPV infection.

Journal of Craniofacial Surgery, 2012

Over the past years, computer-assisted surgery has gained more importance in craniomaxillofacial ... more Over the past years, computer-assisted surgery has gained more importance in craniomaxillofacial surgery, especially in primary and secondary treatment of head and neck malignancies. The basis for oncologic treatment of the head and neck region requires detailed planning using computed tomography, cone-beam computed tomography, or magnetic resonance imaging in combination with computer-assisted, infrared-based navigation system. These techniques allow a preplanned image-guided path to the tumor region for taking biopsies, resection, or reconstruction. The aim of this work was to show the advances and technical benefits for tumor surgery in a daily clinical routine from the view of the craniomaxillofacial surgeon. The target of our working group was to develop and clinically evaluate a novel three-dimensional planning and navigation software solution for treatment of craniofacial tumors. This work was carried out on 5 categories for oncologic surgical procedures in which computer-assisted surgery was applied from 2005 to 2011: preplanned trajectorial-guided tumor biopsy, intraoperative imageYcontrolled tumor resection, tumor mapping, reconstruction after tumor surgery (true to original), and oral rehabilitation (backward planning). Successful preoperative planning, import of image data suitable for navigation, and intraoperative precise infraredbased navigation were obtained for all 5 categories without any complications. Image-guided navigation technique for head and neck oncologic surgery provides a precise, safe surgical method with real-time excellent anatomic orientation. Regarding the advantages of computerassisted surgery, this technique will play a major part in craniofacial reconstructive surgery and will address widespread general methodologic solutions that are of great interest in multidisciplinary oncologic treatment.

Craniomaxillofacial Trauma & Reconstruction, 2010

Reconstruction of mandibular defects following tumor resection in infants is a particular challen... more Reconstruction of mandibular defects following tumor resection in infants is a particular challenge. Although autogenous rib grafts have no relevance in the restoration of mandibular bone defects occurring after ablative tumor surgery due to limited bone stock and the availability of other donor areas, they are a useful surgical alternative following tumor surgery in infants. We here report on a 2, 5, 8, and 15-year follow-up of four children who were diagnosed with benign tumors of the mandible with osseous destruction at the age of 4, 6, 15, and 18 months, respectively. Histologic diagnoses were melanotic neuroectodermal tumor ( n=2), hemangioendothelioma of the mandible ( n=1), and ameloblastoma ( n=1). Following continuity resection of the mandible, lateromandibular bone defects were restored using autogenous rib grafts. Both clinical and radiologic follow-up visits were performed for all children to assess growth of the facial skeleton and the mandible. One child was already fu...

Physical Review A, 2018

We derive a theory for Bose condensation in nonequilibrium steady states of bosonic quantum gases... more We derive a theory for Bose condensation in nonequilibrium steady states of bosonic quantum gases that are coupled both to a thermal heat bath and to a pumped reservoir (or gain medium), while suffering from loss. Such a scenario describes photonic many-body systems such as excitonpolariton gases. Our analysis is based on a set of kinetic equations for a gas of noninteracting bosons. By identifying a dimensionless scaling parameter controlling the boson density, we derive a sharp criterion for which system states become selected to host a macroscopic occupation. We show that with increasing pump power, the system generically undergoes a sequence of nonequilibrum phase transitions. At each transition a state either becomes or ceases to be Bose selected (i.e. to host a condensate): The state which first acquires a condensate when the pumping exceeds a threshold is the one with the largest ratio of pumping to loss. This intuitive behavior resembles simple lasing. In the limit of strong pumping, the coupling to the heat bath becomes dominant so that eventually the ground state is selected, corresponding to equilibrium(-like) Bose condensation. For intermediate pumping strengths, several states become selected giving rise to fragmented nonequilibrium Bose condensation. We compare these predictions to experimental results obtained for excitons polaritons in a double-pillar structure [Phys. Rev. Lett. 108, 126403 (2012)] and find good agreement. Our theory, moreover, predicts that the reservoir occupation is clamped at a constant value whenever the system hosts an odd number of Bose condensates.

Craniomaxillofacial Trauma & Reconstruction Open, 2020

Metastasis to the mandibular condyle and cervical spine in oncologic patients is rare, and clinic... more Metastasis to the mandibular condyle and cervical spine in oncologic patients is rare, and clinicians should therefore be alert if patients present with such suspicious lesions for further clinical and pathological examinations. A 58-year old female patient with uterine cervical cancer initially presented with mild left condylar dysfunction. CT-imaging revealed a progressive osteolytic lesion of the left condyle and at the same time CT-scans revealed an osteolytic lesion of the cervical spine. Further metastatic bone lesions were ruled out. An incisional biopsy of the left condyle revealed metachronous metastasis from the uterine cervical carcinoma. Based on clinical and radiological examinations the patient underwent surgery with total alloplastic replacement of the temporomandibular joint (TMJ) and in a second surgical approach stabilization of the cervical spine. Suspicious symptoms with TMJ dysfunction in conjunction with osteolytic lesions of the maxillofacial skeleton in onco...

British Journal of Cancer, 2007

Despite significant advances in the use of surgery, chemotherapy and radiotherapy to treat squamo... more Despite significant advances in the use of surgery, chemotherapy and radiotherapy to treat squamous cell carcinoma of the head and neck (SCCHN), prognosis has improved little over the past 30 years. There is a clear need for novel, more effective therapies to prevent relapse, control metastases and improve overall survival. Improved understanding of SCCHN disease biology has led to the introduction of molecularly targeted treatment strategies in these cancers. The epidermal growth factor receptor (EGFR) is expressed at much higher levels in SCCHN tumours than in normal epithelial tissue, and EGFR expression correlates with poor prognosis. Therefore, much effort is currently directed toward targeting aberrant EGFR activity (e.g. cell signalling) in SCCHN. This review discusses the efficacy of novel therapies targeting the EGFR (e.g. anti-EGFR antibodies and EGFR tyrosine kinase inhibitors) that are currently tested in SCCHN patients.

Journal of the Korean Association of Oral and Maxillofacial Surgeons, 2013

Reconstruction of oral soft-tissue defects following resection of oral carcinomas can be achieved... more Reconstruction of oral soft-tissue defects following resection of oral carcinomas can be achieved using various techniques including microsurgical tissue transfer. However, there seems to be a role for regional or local flaps. Small to medium-size defects can be functionally reconstructed with the platysma myocutaneous flap as an excellent choice particularly in medically compromised patients not being eligible for free tissue transfer. The present paper reviews the indication, surgical technique, and complications following reconstruction of defects of the oral cavity with the platysma myocutaneous flap.

BMC Cancer, 2014

Background Humans and dogs are affected by squamous cell carcinomas of the oral cavity (OSCC) in ... more Background Humans and dogs are affected by squamous cell carcinomas of the oral cavity (OSCC) in a considerably high frequency. The high mobility group A2 (HMGA2) protein was found to be highly expressed in human OSCC and its expression was suggested to act as a useful predictive and prognostic tool in clinical management of oral carcinomas. Herein the expression of HMGA2 and its sister gene HMGA1 were analysed within human and canine OSCC samples. Additionally, the HMGA negatively regulating miRNAs of the let-7 family as well as the let-7 regulating gene Lin28 were also comparatively analysed. Deregulations of either one of these members could affect the progression of human and canine OSCC. Methods Expression levels of HMGA1, HMGA2, Lin28, let-7a and mir-98 were analysed via relative qPCR in primary human and canine OSCC, thereof derived cell lines and non-neoplastic samples. Additionally, comparative HMGA2 protein expression was analysed by immunohistochemistry. Results In both s...

Head & Neck, 2014

Background-The patterns of regional metastasis in adenoid cystic carcinoma (ACC) of the head and ... more Background-The patterns of regional metastasis in adenoid cystic carcinoma (ACC) of the head and neck and its association with outcome is not established.

Journal of Neurological Surgery Part B: Skull Base, 2013

Objectives To identify independent predictors of outcome in patients with adenoid cystic carcinom... more Objectives To identify independent predictors of outcome in patients with adenoid cystic carcinoma (ACC) of the paranasal sinuses and skull base. Design Meta-analysis of the literature and data from the International ACC Study Group. Setting University-affiliated medical center. Participants The study group consisted of 520 patients, 99 of them from the international cohort. The median follow-up period was 60 months (range, 32 to 100 months). Main Outcome Measures Overall survival (OS) and disease-specific survival (DSS). Results The 5-year OS and DSS of the entire cohort were 62% and 67%, respectively. The local recurrence rate was 36.6%, and the regional recurrence rate was 7%. Distant

World Journal of Surgical Oncology, 2012

Background Cervical metastasis has a tremendous impact on the prognosis in patients with carcinom... more Background Cervical metastasis has a tremendous impact on the prognosis in patients with carcinomas of the head and neck and the frequency of such spread is greater than 20% for most squamous cell carcinomas. With emerging evidence, focus is shifting to conservative neck procedures aimed at achieving good shoulder function without compromising oncologic safety. The purpose of this study was to analyze the pattern of nodal metastasis in patients presenting with squamous cell carcinoma of buccal mucosa. Materials and methods This was a prospective clinical analysis of patients who were histologically diagnosed with squamous cell carcinoma of the buccal cavity and clinically N1 and had not received treatment anywhere else. Patients were analyzed for age and sex distribution, tumor staging, location, and metastasis. Results The incidence of metastatic lymph node in T4 (n=44) was the highest, that is, level I was 100% (44/44), level II was 43.18% (19/44), level III was 15.90% (7/44), and...

World Journal of Surgical Oncology, 2013

Background: Lymphomas of the orbit and orbital adnexae are rare tumors, comprising only 1% of all... more Background: Lymphomas of the orbit and orbital adnexae are rare tumors, comprising only 1% of all non-Hodgkin's lymphoma. The majority of non-Hodgkin's lymphomas of the orbit are extranodal marginal-zone B-cell lymphomas of mucosa-associated lymphoid tissue type. Because of nonspecific clinical signs and symptoms, some diagnostic delay may occur. The purpose of the study was to evaluate the diagnostic approach in orbital lymphomas and to analyze their treatment outcome. Methods: In the period from 2005 to 2012, from a group of 135 patients with tumors of the orbit, we identified 11 patients diagnosed with orbital lymphoma. This patient cohort was reviewed retrospectively. Results: The patient group consisted of 11 patients (seven females, male males) with a median age of 57.7 years (range 42 to 88 years). Orbital swelling, pain and motility impairment were the leading clinical symptoms. Diagnosis was confirmed by surgical biopsy. Depending on the anatomic location of the tumor, a surgical biopsy was taken using a blepharoplasty incision, a lateral orbitotomy or a navigation-guided biopsy. The predominant histology was extranodal non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue type (82%). All patients underwent complete clinical staging. These were clinical stage I EA in seven patients, and stages II EA (n = 2) and III EA (n = 2) in four patients. Patients in stage I EA were treated with radiation therapy alone, with radiation doses between 25 and 40 Gy, and patients with stage II EA received systemic chemotherapy with bendamustin/rituximab. Those two patients diagnosed with diffuse large B-cell lymphoma and mantle cell lymphoma received systemic chemotherapy according to the R-CHOP protocol. Conclusions: Owing to unspecific clinical symptoms, some diagnostic delay may occur in orbital lymphoma. If unspecific orbital symptoms are present, adequate imaging studies followed by early surgical biopsy will contribute to early diagnosis. Once diagnosis is established and staging is complete, radiation therapy is the recommended treatment for stage I EA patients. Systemic chemotherapy is indicated in selected stage II EA patients and in patients with stage III EA disease.

Trials, 2012

Background: The zygoma plays an important role in the facial contour for both cosmetic and functi... more Background: The zygoma plays an important role in the facial contour for both cosmetic and functional reasons; therefore zygomatic bone injuries should be properly diagnosed and adequately treated. Comparison of various surgical approaches and their complications can only be done objectively using outcome measurements which in turn require protocol management and long-term follow up. The preference for open reduction and internal fixation of zygomatic fractures at three points has continued to grow in response to observations of inadequate results from two point and one point fixation techniques. The objectives of this study were to compare the efficacy of zygomatic bone after treatment with ORIF using 2 point fixation and ORIF using 3 point fixation and compare the outcome of two procedures. Methods: 100 patients were randomly divided equally into two groups. In group A, 50 patients were treated by ORIF using two point fixation by miniplates and in group B, 50 patients were treated by ORIF using three point fixation by miniplates. They were evaluated for their complications during and after surgery with their advantages and disadvantages and the difference between the two groups was observed. Results: A total of 100 fractures were sustained. We found that postoperative complication like decreased malar height and vertical dystopia was more common in those patients who were treated by two point fixation than those who were treated with three point fixation. Conclusions: Based on this study open reduction and internal fixation using three point fixation by miniplates is the best available method for the treatment zygomatic bone fractures.

Radiation Oncology, 2011

Background: Preoperative radiotherapy and chemotherapy in patients with head and neck cancer resu... more Background: Preoperative radiotherapy and chemotherapy in patients with head and neck cancer result in changes to the vessels that are used to construct microsurgical anastomoses. The aim of the study was to investigate quantitative changes and HSP70 expression of irradiated neck recipient vessels and transplant vessels used for microsurgical anastomoses. Methods: Of 20 patients included in this study five patients received neoadjuvant chemoradiation, another five received conventional radiotherapy and 10 patients where treated without previous radiotherapy. During surgical procedure, vessel specimens where obtained by the surgeon. Immunhistochemical staining of HSP70 was performed and quantitative measurement and evaluation of HSP70 was carried out.

Radiation Oncology, 2011

The quality of the interdisciplinary interface in oncological treatment between surgery, patholog... more The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient's specific tumor information (invasion to vessels and nerves, non-resectable tumor) to oncologists, radiotherapists and pathologists.

Orphanet Journal of Rare Diseases, 2013

Background Oral sub mucous fibrosis is a rare chronic, progressive, pre malignant collagen disord... more Background Oral sub mucous fibrosis is a rare chronic, progressive, pre malignant collagen disorder of oral mucosa in people of Asian descent characterized by trismus, blanching and stiffness of mucosa, burning sensation in mouth and hypomobility of soft palate and tongue with loss of gustatory sensation. Betel nut chewing is the most common etiological agent. Surgery remains the main stay in severe cases and aims at release of fibrotic bands and resurfacing the raw areas with different options. Reconstruction can be done by using nasolabial flap or radial free forearm flap. The purpose of this study was to compare the mouth opening after the reconstruction with either nasolabial flap or radial free forearm flap. Methods This study was carried out on fifty (50) patients with oral sub mucous fibrosis. Twenty five (25) of these were reconstructed by nasolabial flap and twenty five (25) were reconstructed by radial free forearm flap. At different intervals of their post-operative visit...

Head & face medicine, Jan 9, 2011

A 63 year-old male with a huge odontogenic lesion of sinus maxillaris was treated with computer-a... more A 63 year-old male with a huge odontogenic lesion of sinus maxillaris was treated with computer-assisted surgery. After resection of the odontogenic lesion, the sinus wall was reconstructed with a prebended 3D titanium-mesh using CAD/CAM technique. This work provides a new treatment device for maxillary reconstruction via rapid prototyping procedures.

Head and Neck Pathology, 2013

Caspase 14 is one of the latter discovered members of the caspase enzyme family and, although sha... more Caspase 14 is one of the latter discovered members of the caspase enzyme family and, although sharing sequence homologies with the other caspases, it is not involved in apoptosis. Together with its co-factor filaggrin, it plays an important role in skin barrier formation. It is already known that caspase 14 proteins are reduced during neoplastic dedifferentiation in cervical intraepithelial neoplasms and in invasive cervical carcinomas. Oral squamous carcinoma tissues have not been systematically evaluated for caspase 14 expression yet. Formalin-fixed and paraffin-embedded samples from oral squamous carcinomas (n = 36 tumours from 34 patients), metastases (n = 15) and controls (leukoplakia, n = 10) were analysed by immunohistochemistry. In carcinomas, human papilloma virus (HPV) infection was tested by PCR. Here we demonstrate that, in oral epithelia, caspase 14 is expressed mainly by cells of the intermediate and superficial cell layers while filaggrin is expressed only in keratinising foci in leukoplakia. Caspase 14 and filaggrin are co-localised. In invasive oral carcinomas, reduced expression of caspase 14 was detectable in 47 % of tumours but was not associated with keratinisation, tumour differentiation or HPV infection. Filaggrin was detectable in a subfraction of tumours (56 %) and was restricted to keratinising areas of the carcinomas. In summary, in contrast to cervical carcinomas, partial loss of caspase 14 is not associated with dedifferentiation in neoplastic lesions of the oral mucosa or HPV infection.