Luz Rivera | ITM - Instituto Tecnológico Metropolitano (original) (raw)
Papers by Luz Rivera
Oral Oncology, 1999
Relatively rare squamous cell carcinomas of the tongue in young patients may be associated with d... more Relatively rare squamous cell carcinomas of the tongue in young patients may be associated with dierent etiologic factors and pathogenetic mechanisms than carcinomas from the same site in older patients. Alterations in cell cycle proteins likely contribute to the biologic behavior of these neoplasms. The purpose of this investigation was to evaluate cell cycle proteins (p53, p21, Rb, MDM2) in lateral tongue cancers from patients at the two ends of the age spectrum. All available archived lateral tongue carcinomas from patients <35 years (n=36, 23 males and 13 females) were sectioned, immunohistochemically stained, and evaluated. Protein expression was scored as percent positive nuclei. An equal number of sequentially accessioned lateral tongue specimens from patients >75 years (23 males and 13 females) were stained and compared. Positive p53 staining was seen in 18/36 of the <35year group versus 24/36 of the >75-year group ( p=0.149). Increased p21 staining (both percent of positive cells and intensity) was evident in 25/32 of the <35-year group versus 24/32 of the >75-year group ( p=1.0). Increased p21 expression was seen in both p53-positive and -negative cases in both age groups. Rb protein was increased in 16/29 of the <35-year group versus 17/26 of the >75-year group ( p=0.58). Fourteen cases (4/35 vs 10/36, p=0.135) showed positive MDM2 staining; MDM2-positive cases were also p53 positive in 4/4 younger and 8/10 older patients. We conclude that p53, p21, Rb, and MDM2 are over-expressed in lateral tongue cancers, and that immunohistochemical pro®les are heterogeneous. A p53-independent pathway of p21 induction is supported by the results; p53 suppression may be associated with MDM2 protein expression in a subset of cancers. Signi®cant dierences in the expression of p53, p21, Rb, and MDM2 proteins are not evident in lateral tongue carcinomas from patients <35 years as compared to patients >75 years. # (J.A. Regezi).
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 1997
Reports about the frequency of odontogenic tumors are scarce, and diagnostic criteria used in the... more Reports about the frequency of odontogenic tumors are scarce, and diagnostic criteria used in the reports are not uniform. This article presents the results of a retrospective study of odontogenic tumors recorded in four services of diagnostic pathology in Mexico City (two dental schools, one cancer hospital, and one private oral pathology service). The final diagnosis in each case was based on tbe 1992 histologic criteria of the World Health Organization. The frequency of odontogenic tumors, expressed as a percent of all oral and maxillofacial specimens, ranged from 0.8% in the cancer hospital (0.02% of all biopsies) to 3.7% in the private oral pathology service. The frequency was identical for the two dental school s (2.5%). We found a total of 349 odontogenic tumors; of these, 345 were benign (98.8%), and 4 (1.1%) were malignant (3 were primary intraosseous carcinomas and 1 was a malignant ameloblastoma). The most frequently occurring tumors were odontoma (34.6%), ameloblastoma (23.7%), myxoma (17.7%), adenomatoid odontogenic tumor (7.1%), and calcifying odontogenic cyst (6.8%). Although relatively rare, odontogenic tumors are still an important cause of extensive surgical procedures in
Journal of Oral Pathology & Medicine, 1997
Angiocentric lymphomas (AL) involving the mid-face are infrequent lesions. Their incidence seems ... more Angiocentric lymphomas (AL) involving the mid-face are infrequent lesions. Their incidence seems to be higher in certain Asian and Latin American countries, where most of the reported series reveal a predominance of T-cell lineage and a high frequency of EBV-positive cells. The clinical and pathological features of 12 AL that affected the palate are presented. Immunophenotypic studies were performed in nine of these cases. Seven (77%) demonstrated T-cell lineage, one was of B-cell origin and one could not be classified. The high incidence of T-cell lesions in this and other studies supports the existence of geographical and possibly of etiological differences in these neoplasms.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2002
Paracoccidioidomycosis is an endemic fungal infection in Latin America. This mucocutaneous diseas... more Paracoccidioidomycosis is an endemic fungal infection in Latin America. This mucocutaneous disease often involves the oral mucosa and may clinically resemble other infectious and neoplastic processes. Paracoccidioidomycosis that clinically suggested squamous cell carcinoma was diagnosed in 2 patients with a history of heavy alcohol and tobacco use. Antifungal therapy with ketoconazole and itraconazole resulted in resolution of the oral lesions. Interestingly, 1 patient had a pulmonary lesion that persisted after antifungal therapy, and biopsy proved this to be a squamous cell carcinoma of the lung.
Journal of Oral Pathology & Medicine, 2002
This article describes a case of clear cell odontogenic carcinoma (CCOC) in a 55-year-old woman w... more This article describes a case of clear cell odontogenic carcinoma (CCOC) in a 55-year-old woman who presented such a tumor extending from the midline of the mandible to the right first molar. The tumor was surgically excised and has not recurred or metastasized 6 months after surgery. To date, only 33 well-documented cases have been reported (including the present case) in the English literature. Twenty-eight (84.8%) have developed in the mandible and five (15.2%) in the maxilla. Eighteen (54.5%) occurred anterior to the first molar. The vast majority have been diagnosed in patients older than 40 years (30/33), and the mean age at diagnosis is 57.4 years (range: 17–89), with a male/female ratio: 1/2. Recurrences have been described in 17 cases (51.5%) and metastasis in 10 (30.3%). Based on its morphologic, histochemical and immunophenotypic features, CCOC should be distinguished from other primary and metastasic clear cell tumors of the oral and maxillofacial regions.
Oral Oncology, 1999
Relatively rare squamous cell carcinomas of the tongue in young patients may be associated with d... more Relatively rare squamous cell carcinomas of the tongue in young patients may be associated with dierent etiologic factors and pathogenetic mechanisms than carcinomas from the same site in older patients. Alterations in cell cycle proteins likely contribute to the biologic behavior of these neoplasms. The purpose of this investigation was to evaluate cell cycle proteins (p53, p21, Rb, MDM2) in lateral tongue cancers from patients at the two ends of the age spectrum. All available archived lateral tongue carcinomas from patients <35 years (n=36, 23 males and 13 females) were sectioned, immunohistochemically stained, and evaluated. Protein expression was scored as percent positive nuclei. An equal number of sequentially accessioned lateral tongue specimens from patients >75 years (23 males and 13 females) were stained and compared. Positive p53 staining was seen in 18/36 of the <35year group versus 24/36 of the >75-year group ( p=0.149). Increased p21 staining (both percent of positive cells and intensity) was evident in 25/32 of the <35-year group versus 24/32 of the >75-year group ( p=1.0). Increased p21 expression was seen in both p53-positive and -negative cases in both age groups. Rb protein was increased in 16/29 of the <35-year group versus 17/26 of the >75-year group ( p=0.58). Fourteen cases (4/35 vs 10/36, p=0.135) showed positive MDM2 staining; MDM2-positive cases were also p53 positive in 4/4 younger and 8/10 older patients. We conclude that p53, p21, Rb, and MDM2 are over-expressed in lateral tongue cancers, and that immunohistochemical pro®les are heterogeneous. A p53-independent pathway of p21 induction is supported by the results; p53 suppression may be associated with MDM2 protein expression in a subset of cancers. Signi®cant dierences in the expression of p53, p21, Rb, and MDM2 proteins are not evident in lateral tongue carcinomas from patients <35 years as compared to patients >75 years. # (J.A. Regezi).
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 1997
Reports about the frequency of odontogenic tumors are scarce, and diagnostic criteria used in the... more Reports about the frequency of odontogenic tumors are scarce, and diagnostic criteria used in the reports are not uniform. This article presents the results of a retrospective study of odontogenic tumors recorded in four services of diagnostic pathology in Mexico City (two dental schools, one cancer hospital, and one private oral pathology service). The final diagnosis in each case was based on tbe 1992 histologic criteria of the World Health Organization. The frequency of odontogenic tumors, expressed as a percent of all oral and maxillofacial specimens, ranged from 0.8% in the cancer hospital (0.02% of all biopsies) to 3.7% in the private oral pathology service. The frequency was identical for the two dental school s (2.5%). We found a total of 349 odontogenic tumors; of these, 345 were benign (98.8%), and 4 (1.1%) were malignant (3 were primary intraosseous carcinomas and 1 was a malignant ameloblastoma). The most frequently occurring tumors were odontoma (34.6%), ameloblastoma (23.7%), myxoma (17.7%), adenomatoid odontogenic tumor (7.1%), and calcifying odontogenic cyst (6.8%). Although relatively rare, odontogenic tumors are still an important cause of extensive surgical procedures in
Journal of Oral Pathology & Medicine, 1997
Angiocentric lymphomas (AL) involving the mid-face are infrequent lesions. Their incidence seems ... more Angiocentric lymphomas (AL) involving the mid-face are infrequent lesions. Their incidence seems to be higher in certain Asian and Latin American countries, where most of the reported series reveal a predominance of T-cell lineage and a high frequency of EBV-positive cells. The clinical and pathological features of 12 AL that affected the palate are presented. Immunophenotypic studies were performed in nine of these cases. Seven (77%) demonstrated T-cell lineage, one was of B-cell origin and one could not be classified. The high incidence of T-cell lesions in this and other studies supports the existence of geographical and possibly of etiological differences in these neoplasms.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2002
Paracoccidioidomycosis is an endemic fungal infection in Latin America. This mucocutaneous diseas... more Paracoccidioidomycosis is an endemic fungal infection in Latin America. This mucocutaneous disease often involves the oral mucosa and may clinically resemble other infectious and neoplastic processes. Paracoccidioidomycosis that clinically suggested squamous cell carcinoma was diagnosed in 2 patients with a history of heavy alcohol and tobacco use. Antifungal therapy with ketoconazole and itraconazole resulted in resolution of the oral lesions. Interestingly, 1 patient had a pulmonary lesion that persisted after antifungal therapy, and biopsy proved this to be a squamous cell carcinoma of the lung.
Journal of Oral Pathology & Medicine, 2002
This article describes a case of clear cell odontogenic carcinoma (CCOC) in a 55-year-old woman w... more This article describes a case of clear cell odontogenic carcinoma (CCOC) in a 55-year-old woman who presented such a tumor extending from the midline of the mandible to the right first molar. The tumor was surgically excised and has not recurred or metastasized 6 months after surgery. To date, only 33 well-documented cases have been reported (including the present case) in the English literature. Twenty-eight (84.8%) have developed in the mandible and five (15.2%) in the maxilla. Eighteen (54.5%) occurred anterior to the first molar. The vast majority have been diagnosed in patients older than 40 years (30/33), and the mean age at diagnosis is 57.4 years (range: 17–89), with a male/female ratio: 1/2. Recurrences have been described in 17 cases (51.5%) and metastasis in 10 (30.3%). Based on its morphologic, histochemical and immunophenotypic features, CCOC should be distinguished from other primary and metastasic clear cell tumors of the oral and maxillofacial regions.