Zia Aftab - Academia.edu (original) (raw)

Papers by Zia Aftab

Scientific Reports, Sep 12, 2018

Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk ... more Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk of developing distant metastasis could benefit from appropriate adjuvant and follow-up treatments if stratified accurately at an early stage of the disease. Studies have increasingly recognized the role of diverse cellular components within the tumor microenvironment in the development and progression of CRC tumors. In this paper, we show that automated analysis of digitized images from locally advanced colorectal cancer tissue slides can provide estimate of risk of distant metastasis on the basis of novel tissue phenotypic signatures of the tumor microenvironment. Specifically, we determine what cell types are found in the vicinity of other cell types, and in what numbers, rather than concentrating exclusively on the cancerous cells. We then extract novel tissue phenotypic signatures using statistical measurements about tissue composition. Such signatures can underpin clinical decisions about the advisability of various types of adjuvant therapy.

British Journal of Surgery, Dec 1, 2020

Biomedical sciences, 2020

Bile duct stones (BDS) are usually secondary to gallstones but may be found primarily in biliary ... more Bile duct stones (BDS) are usually secondary to gallstones but may be found primarily in biliary system, although the percentage is minimal. They are usually suspected on history and clinical examination alone but symptoms may be variable ranging from asymptomatic to complications such as biliary colic, pancreatitis, jaundice or cholangitis, the latter can be life-threatening in some patients. Abnormalities in the liver function tests especially the elevated direct bilirubin and alkaline phosphatase indirectly raise the suspicion. The majority of BDS can be diagnosed by Transabdominal Ultrasound, but in some cases further imaging such as, Computed Tomography, Endoscopic Ultrasound or Magnetic Resonance Cholangiography are employed prior to endoscopic or laparoscopic removal. Approximately 90% of BDS can be removed following Endoscopic Retrograde Cholangiography (ERC) + sphincterotomy. Most of the remaining stones can be removed using mechanical lithotripsy. Patients with uncorrected coagulopathies may be treated with ERC + pneumatic dilatation of the sphincter of Oddi. Shockwave lithotripsy (intraductal and extracorporeal) and laser lithotripsy have also been used to fragment large bile duct stones prior to endoscopic removal. Despite all the minimally invasive procedures the role of open surgery for the removal of difficult or impacted stones cannot be completely forgotten. The role of medical therapy in treatment of BDS is currently uncertain. This review focuses on the clinical presentation, investigation and current management of BDS.

Sultan Qaboos University Medical Journal, Mar 1, 2008

arXiv (Cornell University), Jan 23, 2018

Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk ... more Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk of developing distant metastasis could benefit from appropriate adjuvant and follow-up treatments if stratified accurately at an early stage of the disease. Studies have increasingly recognized the role of diverse cellular components within the tumor microenvironment in the development and progression of CRC tumors. In this paper, we show that a new method of automated analysis of digitized images from colorectal cancer tissue slides can provide important estimates of distant metastasis-free survival (DMFS, the time before metastasis is first observed) on the basis of details of the microenvironment. Specifically, we determine what cell types are found in the vicinity of other cell types, and in what numbers, rather than concentrating exclusively on the cancerous cells. We then extract novel tissue phenotypic signatures using statistical measurements about tissue composition. Such signatures can underpin clinical decisions about the advisability of various types of adjuvant therapy.

Gastroenterology Research and Practice, 2014

Introduction. Aim of the present work is to review the literature to point out the role of laparo... more Introduction. Aim of the present work is to review the literature to point out the role of laparoscopic reversal of Hartmann procedure. Material and Methods. Number of patients, age, sex, etiology, Hinchey classification, interval between procedure and reversal, position of the first trocars, mean operative time (min), number and causes of conversion, length of stay, mortality, complications, and quality of life were considered. Results. 238 males (52.4%) and 216 females (47.6%) between 38 and 67 years were analyzed. The etiology was diverticulitis in 292 patients (72.1%), carcinoma in 43 patients (10.6%), and other in 70 patients (17.3%). Only 7 articles (22.6%) reported Hinchey classification. The interval between initial procedure and reversal was between 50 and 330 days. The initial trocar was open positioned in 182 patients (43.2%) through umbilical incision, in 177 patients (41.9%) in right upper quadrant, and in 63 patients (14.9%) in colostomy site. The operative time was between 69 and 285 minutes. A total of 83 patients (12.1%) were converted and the causes were reported in 67.4%. The length of stay was between 3 and 12 days. 5 patients (0.7%) died. The complications concern 112 cases (16.4%). Conclusion. The laparoscopic Hartmann's reversal is safer and achieves faster positive results.

Clinical Case Reports, 2019

Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surge... more Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surgeon as the clinical presentation and radiological findings mimic perforated viscus resulting in unnecessary surgical intervention. The aim of this article is to describe a case of a spontaneous pneumoperitoneum in an elderly patient who underwent diagnostic laparoscopy and review of literature. Case presentation: A 77-year-old female with multiple comorbidities presented to the emergency department with productive cough, shortness of breath, vomiting and abdominal pain. On examination she had tenderness in epigastric region. Chest X-ray and CT showed free air and fluid in peritoneal cavity. Results: The patient underwent diagnostic laparoscopy that did not reveal any gastrointestinal perforation. Conclusion: Spontaneous pneumoperitoneum is frequently mistaken for perforated viscus. If the patient presents with features of peritonitis, diagnostic laparoscopy has a vital role as it prevents unnecessary midline laparotomy.

PubMed, Jun 1, 2005

Intussusception in adults is a rare cause for intestinal obstruction and is usually secondary to ... more Intussusception in adults is a rare cause for intestinal obstruction and is usually secondary to some lesion in the gastrointestinal tract GIT. We report a case of intestinal obstruction due to ileo-colic intussusception; an inflammatory fibroid polyp formed the leading edge of the intussusceptum, which is a rare polypoidal lesion of the GIT.

World Journal of Emergency Surgery, Jun 30, 2014

Sigmoid volvulus is a rare, but serious, complication that can occur during pregnancy. We present... more Sigmoid volvulus is a rare, but serious, complication that can occur during pregnancy. We present a case of a 33-year-old pregnant female in the third trimester with a sigmoid volvulus. Detorsion of the volvulus was performed during colonoscopy. The patient underwent an elective sigmoidectomy at a later date. Prompt diagnosis of the volvulus sigmoid is critical to minimize fetal and maternal morbidity and mortality. Sigmoidoscopic detorsion or surgical resection are the treatment options, depending on bowel viability. A review of the literature was done.

American Journal of Case Reports, Jan 24, 2020

Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare... more Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare phenomenon in adults particularly in patients with history of pulmonary tuberculosis, but commonly seen in pediatric population. Mostly it occurs along the duodenum in the paraduodenal recesses. The patient might be misdiagnosed as having obstruction secondary to strictures formed as a result of intestinal tuberculosis and pose delay in exploration. Case Report: We describe an adult patient who presented with intestinal obstruction by a tourniquet or ring formed between the tip of appendix and ileocecal junction through which small bowel herniated, strangulated and finally perforated before exploration, initially thought to be due to intestinal tuberculosis. He underwent exploratory laparotomy and was release of obstruction, appendectomy and resection of bowel. The patient tolerated the procedure well and discharged in stable condition. Conclusions: Intestinal obstruction due to internal hernia is rare in adults. Computed tomography abdomen can diagnose the condition; however, exploration of the abdomen can give the definite diagnosis and tailor the appropriate therapy.

American Journal of Case Reports

Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare... more Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare phenomenon in adults particularly in patients with history of pulmonary tuberculosis, but commonly seen in pediatric population. Mostly it occurs along the duodenum in the paraduodenal recesses. The patient might be misdiagnosed as having obstruction secondary to strictures formed as a result of intestinal tuberculosis and pose delay in exploration. Case Report: We describe an adult patient who presented with intestinal obstruction by a tourniquet or ring formed between the tip of appendix and ileocecal junction through which small bowel herniated, strangulated and finally perforated before exploration, initially thought to be due to intestinal tuberculosis. He underwent exploratory laparotomy and was release of obstruction, appendectomy and resection of bowel. The patient tolerated the procedure well and discharged in stable condition. Conclusions: Intestinal obstruction due to internal hernia is rare in adults. Computed tomography abdomen can diagnose the condition; however, exploration of the abdomen can give the definite diagnosis and tailor the appropriate therapy.

Clinical Case Reports, 2019

Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surge... more Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surgeon as the clinical presentation and radiological findings mimic perforated viscus resulting in unnecessary surgical intervention. The aim of this article is to describe a case of a spontaneous pneumoperitoneum in an elderly patient who underwent diagnostic laparoscopy and review of literature. Case presentation: A 77-year-old female with multiple comorbidities presented to the emergency department with productive cough, shortness of breath, vomiting and abdominal pain. On examination she had tenderness in epigastric region. Chest X-ray and CT showed free air and fluid in peritoneal cavity. Results: The patient underwent diagnostic laparoscopy that did not reveal any gastrointestinal perforation. Conclusion: Spontaneous pneumoperitoneum is frequently mistaken for perforated viscus. If the patient presents with features of peritonitis, diagnostic laparoscopy has a vital role as it prevents unnecessary midline laparotomy.

Foreign body in the liver: Case report and review

In this note, we have described the quality assurance tests performed for endcap Resistive Plate ... more In this note, we have described the quality assurance tests performed for endcap Resistive Plate Chambers (RPCs) at two different sites, Pakistan Atomic Energy Commission (PAEC) and National Centre for Physics (NCP), in Pakistan. This paper describes various quality assurance tests both at the level of gas gaps and the chambers. The data has been obtained at different time windows during the large scale production of CMS RPCs of RE2/2 and RE2/3 type. In the quality assurance tests, we have investigated parameters like dark current, strip occupancy, cluster size and efficiency of RPCs.

COVID-19 can present in many ways that need to be recognized early, to protect the medical staff ... more COVID-19 can present in many ways that need to be recognized early, to protect the medical staff from exposure/infection, by isolation of affected patients. We report a case, who presented with acute abdominal pain and on investigations was found to have features of acute appendicitis, without any pulmonary symptoms, and tested positive for COVID-19. He was treated conservatively for appendicitis with antibiotics and recovered well but developed full blown COVID-19 pneumonia after three days. This report signifies that COVID-19 infections may present as acute abdominal pain and appendicitis, in our case, the screening protocol helped us to identify this patient and helped to avoid exposure and possible infection to healthcare staff and avoidance of presumably unnecessary appendectomy.

The British Journal of Surgery, 2020

Scientific Reports, Sep 12, 2018

Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk ... more Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk of developing distant metastasis could benefit from appropriate adjuvant and follow-up treatments if stratified accurately at an early stage of the disease. Studies have increasingly recognized the role of diverse cellular components within the tumor microenvironment in the development and progression of CRC tumors. In this paper, we show that automated analysis of digitized images from locally advanced colorectal cancer tissue slides can provide estimate of risk of distant metastasis on the basis of novel tissue phenotypic signatures of the tumor microenvironment. Specifically, we determine what cell types are found in the vicinity of other cell types, and in what numbers, rather than concentrating exclusively on the cancerous cells. We then extract novel tissue phenotypic signatures using statistical measurements about tissue composition. Such signatures can underpin clinical decisions about the advisability of various types of adjuvant therapy.

British Journal of Surgery, Dec 1, 2020

Biomedical sciences, 2020

Bile duct stones (BDS) are usually secondary to gallstones but may be found primarily in biliary ... more Bile duct stones (BDS) are usually secondary to gallstones but may be found primarily in biliary system, although the percentage is minimal. They are usually suspected on history and clinical examination alone but symptoms may be variable ranging from asymptomatic to complications such as biliary colic, pancreatitis, jaundice or cholangitis, the latter can be life-threatening in some patients. Abnormalities in the liver function tests especially the elevated direct bilirubin and alkaline phosphatase indirectly raise the suspicion. The majority of BDS can be diagnosed by Transabdominal Ultrasound, but in some cases further imaging such as, Computed Tomography, Endoscopic Ultrasound or Magnetic Resonance Cholangiography are employed prior to endoscopic or laparoscopic removal. Approximately 90% of BDS can be removed following Endoscopic Retrograde Cholangiography (ERC) + sphincterotomy. Most of the remaining stones can be removed using mechanical lithotripsy. Patients with uncorrected coagulopathies may be treated with ERC + pneumatic dilatation of the sphincter of Oddi. Shockwave lithotripsy (intraductal and extracorporeal) and laser lithotripsy have also been used to fragment large bile duct stones prior to endoscopic removal. Despite all the minimally invasive procedures the role of open surgery for the removal of difficult or impacted stones cannot be completely forgotten. The role of medical therapy in treatment of BDS is currently uncertain. This review focuses on the clinical presentation, investigation and current management of BDS.

Sultan Qaboos University Medical Journal, Mar 1, 2008

arXiv (Cornell University), Jan 23, 2018

Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk ... more Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk of developing distant metastasis could benefit from appropriate adjuvant and follow-up treatments if stratified accurately at an early stage of the disease. Studies have increasingly recognized the role of diverse cellular components within the tumor microenvironment in the development and progression of CRC tumors. In this paper, we show that a new method of automated analysis of digitized images from colorectal cancer tissue slides can provide important estimates of distant metastasis-free survival (DMFS, the time before metastasis is first observed) on the basis of details of the microenvironment. Specifically, we determine what cell types are found in the vicinity of other cell types, and in what numbers, rather than concentrating exclusively on the cancerous cells. We then extract novel tissue phenotypic signatures using statistical measurements about tissue composition. Such signatures can underpin clinical decisions about the advisability of various types of adjuvant therapy.

Gastroenterology Research and Practice, 2014

Introduction. Aim of the present work is to review the literature to point out the role of laparo... more Introduction. Aim of the present work is to review the literature to point out the role of laparoscopic reversal of Hartmann procedure. Material and Methods. Number of patients, age, sex, etiology, Hinchey classification, interval between procedure and reversal, position of the first trocars, mean operative time (min), number and causes of conversion, length of stay, mortality, complications, and quality of life were considered. Results. 238 males (52.4%) and 216 females (47.6%) between 38 and 67 years were analyzed. The etiology was diverticulitis in 292 patients (72.1%), carcinoma in 43 patients (10.6%), and other in 70 patients (17.3%). Only 7 articles (22.6%) reported Hinchey classification. The interval between initial procedure and reversal was between 50 and 330 days. The initial trocar was open positioned in 182 patients (43.2%) through umbilical incision, in 177 patients (41.9%) in right upper quadrant, and in 63 patients (14.9%) in colostomy site. The operative time was between 69 and 285 minutes. A total of 83 patients (12.1%) were converted and the causes were reported in 67.4%. The length of stay was between 3 and 12 days. 5 patients (0.7%) died. The complications concern 112 cases (16.4%). Conclusion. The laparoscopic Hartmann's reversal is safer and achieves faster positive results.

Clinical Case Reports, 2019

Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surge... more Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surgeon as the clinical presentation and radiological findings mimic perforated viscus resulting in unnecessary surgical intervention. The aim of this article is to describe a case of a spontaneous pneumoperitoneum in an elderly patient who underwent diagnostic laparoscopy and review of literature. Case presentation: A 77-year-old female with multiple comorbidities presented to the emergency department with productive cough, shortness of breath, vomiting and abdominal pain. On examination she had tenderness in epigastric region. Chest X-ray and CT showed free air and fluid in peritoneal cavity. Results: The patient underwent diagnostic laparoscopy that did not reveal any gastrointestinal perforation. Conclusion: Spontaneous pneumoperitoneum is frequently mistaken for perforated viscus. If the patient presents with features of peritonitis, diagnostic laparoscopy has a vital role as it prevents unnecessary midline laparotomy.

PubMed, Jun 1, 2005

Intussusception in adults is a rare cause for intestinal obstruction and is usually secondary to ... more Intussusception in adults is a rare cause for intestinal obstruction and is usually secondary to some lesion in the gastrointestinal tract GIT. We report a case of intestinal obstruction due to ileo-colic intussusception; an inflammatory fibroid polyp formed the leading edge of the intussusceptum, which is a rare polypoidal lesion of the GIT.

World Journal of Emergency Surgery, Jun 30, 2014

Sigmoid volvulus is a rare, but serious, complication that can occur during pregnancy. We present... more Sigmoid volvulus is a rare, but serious, complication that can occur during pregnancy. We present a case of a 33-year-old pregnant female in the third trimester with a sigmoid volvulus. Detorsion of the volvulus was performed during colonoscopy. The patient underwent an elective sigmoidectomy at a later date. Prompt diagnosis of the volvulus sigmoid is critical to minimize fetal and maternal morbidity and mortality. Sigmoidoscopic detorsion or surgical resection are the treatment options, depending on bowel viability. A review of the literature was done.

American Journal of Case Reports, Jan 24, 2020

Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare... more Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare phenomenon in adults particularly in patients with history of pulmonary tuberculosis, but commonly seen in pediatric population. Mostly it occurs along the duodenum in the paraduodenal recesses. The patient might be misdiagnosed as having obstruction secondary to strictures formed as a result of intestinal tuberculosis and pose delay in exploration. Case Report: We describe an adult patient who presented with intestinal obstruction by a tourniquet or ring formed between the tip of appendix and ileocecal junction through which small bowel herniated, strangulated and finally perforated before exploration, initially thought to be due to intestinal tuberculosis. He underwent exploratory laparotomy and was release of obstruction, appendectomy and resection of bowel. The patient tolerated the procedure well and discharged in stable condition. Conclusions: Intestinal obstruction due to internal hernia is rare in adults. Computed tomography abdomen can diagnose the condition; however, exploration of the abdomen can give the definite diagnosis and tailor the appropriate therapy.

American Journal of Case Reports

Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare... more Objective: Rare disease Background: Intestinal obstruction secondary to internal hernia is a rare phenomenon in adults particularly in patients with history of pulmonary tuberculosis, but commonly seen in pediatric population. Mostly it occurs along the duodenum in the paraduodenal recesses. The patient might be misdiagnosed as having obstruction secondary to strictures formed as a result of intestinal tuberculosis and pose delay in exploration. Case Report: We describe an adult patient who presented with intestinal obstruction by a tourniquet or ring formed between the tip of appendix and ileocecal junction through which small bowel herniated, strangulated and finally perforated before exploration, initially thought to be due to intestinal tuberculosis. He underwent exploratory laparotomy and was release of obstruction, appendectomy and resection of bowel. The patient tolerated the procedure well and discharged in stable condition. Conclusions: Intestinal obstruction due to internal hernia is rare in adults. Computed tomography abdomen can diagnose the condition; however, exploration of the abdomen can give the definite diagnosis and tailor the appropriate therapy.

Clinical Case Reports, 2019

Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surge... more Objective: Spontaneous pneumoperitoneum is a rare condition. It presents a challenge to the surgeon as the clinical presentation and radiological findings mimic perforated viscus resulting in unnecessary surgical intervention. The aim of this article is to describe a case of a spontaneous pneumoperitoneum in an elderly patient who underwent diagnostic laparoscopy and review of literature. Case presentation: A 77-year-old female with multiple comorbidities presented to the emergency department with productive cough, shortness of breath, vomiting and abdominal pain. On examination she had tenderness in epigastric region. Chest X-ray and CT showed free air and fluid in peritoneal cavity. Results: The patient underwent diagnostic laparoscopy that did not reveal any gastrointestinal perforation. Conclusion: Spontaneous pneumoperitoneum is frequently mistaken for perforated viscus. If the patient presents with features of peritonitis, diagnostic laparoscopy has a vital role as it prevents unnecessary midline laparotomy.

Foreign body in the liver: Case report and review

In this note, we have described the quality assurance tests performed for endcap Resistive Plate ... more In this note, we have described the quality assurance tests performed for endcap Resistive Plate Chambers (RPCs) at two different sites, Pakistan Atomic Energy Commission (PAEC) and National Centre for Physics (NCP), in Pakistan. This paper describes various quality assurance tests both at the level of gas gaps and the chambers. The data has been obtained at different time windows during the large scale production of CMS RPCs of RE2/2 and RE2/3 type. In the quality assurance tests, we have investigated parameters like dark current, strip occupancy, cluster size and efficiency of RPCs.

COVID-19 can present in many ways that need to be recognized early, to protect the medical staff ... more COVID-19 can present in many ways that need to be recognized early, to protect the medical staff from exposure/infection, by isolation of affected patients. We report a case, who presented with acute abdominal pain and on investigations was found to have features of acute appendicitis, without any pulmonary symptoms, and tested positive for COVID-19. He was treated conservatively for appendicitis with antibiotics and recovered well but developed full blown COVID-19 pneumonia after three days. This report signifies that COVID-19 infections may present as acute abdominal pain and appendicitis, in our case, the screening protocol helped us to identify this patient and helped to avoid exposure and possible infection to healthcare staff and avoidance of presumably unnecessary appendectomy.

The British Journal of Surgery, 2020