Senthilkumar Perumal

A gist of gastrointestinal stromal tumors: A review.

Gastrointestinal stromal tumors (GISTs) have been recognized as a biologically distinctive tumor type, different from smooth muscle and neural tumors of the gastrointestinal tract (GIT). They constitute the majority of gastrointestinal mesenchymal tumors of the GIT and are known to be refractory to conventional chemotherapy or radiation. They are defined and diagnosed by the expression of a proto-oncogene protein detected by immunohistochemistry which serves as a crucial diagnostic and therapeutic target. The identification of these mutations has resulted in a better understanding of their oncogenic mechanisms. The remarkable antitumor effects of the molecular inhibitor imatinib have necessitated accurate diagnosis of GIST and their distinction from other gastrointestinal mesenchymal tumors. Both traditional and minimally invasive surgery are used to remove these tumors with minimal morbidity and excellent perioperative outcomes. The revolutionary use of specific, molecularly-targeted therapies, such as imatinib mesylate, reduces the frequency of disease recurrence when used as an adjuvant following complete resection. Neoadjuvant treatment with these agents appears to stabilize disease in the majority of patients and may reduce the extent of surgical resection required for subsequent complete tumor removal. The important interplay between the molecular genetics of GIST and responses to targeted therapeutics serves as a model for the study of targeted therapies in other solid tumors. This review summarizes our current knowledge and recent advances regarding the histogenesis, pathology, molecular biology, the basis for the novel targeted cancer therapy and current evidence based management of these unique tumors.

Biliary Cystadenomas: A Case for Complete Resection

Introduction and Objective. Biliary cystadenoma is a rare benign neoplasm of the liver with less than 200 cases being reported allover the world. We report a series of 13 cases highlighting the radiological findings and problems related to its management. Materials and Methods. Records of thirteen patients who underwent surgery for biliary cystadenomas, between March 2006 and October 2011, were reviewed retrospectively. Results. Majority of the patients were females (11 out of 13), with a median age of 46 (23–65) years. The most frequent symptom was abdominal pain (92%). Seven patients had presented with history of previous surgery for liver lesions. Five patients had presented with recurrence after partial resection for a suspected hydatid cyst and two after surgery for presumed simple liver cyst. Ten of the 13 patients had complete resection of the cyst with enucleation in 3 patients, 2 of whom in addition required T-tube drainage of the bile duct. There has been no recurrence during the follow-up period ranging from 3 months to 5 years. Conclusion. Biliary cystadenoma must be differentiated from other benign cysts. Hepatic resection or cyst enucleation is the recommended treatment option.

Outcome of video-assisted translumbar retroperitoneal necrosectomy and closed lavage for severe necrotizing pancreatitis.

Surgery for necrotizing pancreatitis is associated with a high rate of morbidity and mortality. We present a series of 26 patients who underwent video‐assisted translumbar retroperitoneal necrosectomy and analyse their outcomes.

Predictors of malignancy in chronic calcific pancreatitis with head mass.

AIM To prospectively analyse the clinical, biochemical and radiological characteristics of the mass lesions arising in a background of chronic calcific pancreatitis (CCP). METHODS Eighty three patients, who presented with chronic pancreatitis (CP) and a mass lesion in the head of pancreas between February 2005 and December 2011, were included in the study. Patients who were identified to have malignancy underwent Whipples procedure and patients whose investigations were suggestive of a benign lesion underwent Freys procedure. Student t-test was used to compare the mean values of imaging findings [common bile duct (CBD), main pancreatic duct (MPD) size] and laboratory data [Serum bilirubin, carbohydrate antigen 19-9 (CA 19-9)] between the groups. Receiver operating characteristic curve (ROC curve) analysis was done to calculate the cutoff valves of serum bilirubin, CA 19-9, MPD and CBD size. The sensitivity, specificity, positive predictive valve (PPV) and negative predictive value (NPV) were calculated using these cut off points. Multivariate analysis was performed using logistic regression model. RESULTS The study included 56 men (67.5%) and 27 women (32.5%). Sixty (72.3%) patients had tropical calcific pancreatitis and 23 (27.7%) had alcohol related CCP. Histologically, it was confirmed that 55 (66.3%) of the 83 patients had an inflammatory head mass and 28 (33.7%) had a malignant head mass. The mean age of individuals with benign inflammatory mass and those with malignant mass was 38.4 years and 45 years respectively. Significant clinical features that predicted a malignant head mass in CP were presence of a head mass in CCP of tropics, old age, jaundice, sudden worsening abdominal pain, gastric outlet obstruction and significant weight loss (P ≤ 0.05). The ROC curve analysis showed a cut off value of 5.8 mg/dL for serum bilirubin, 127 U/mL for CA 19-9, 11.5 mm for MPD size and 14.5 mm for CBD size. CONCLUSION Elevated Serum bilirubin and CA 19-9, and dilated MPD and CBD were useful in predicting malignancy in patients with CCP and head mass.