A Rare Presentation of Recurrent Malignant Peripheral Nerve Sheath Tumor with Glandular Differentiation-A Case Report.

Malignant peripheral nerve sheath tumors (MPNST) are rare heterogeneous group of soft tissue neoplasms. In most cases, they originate within the pre-existing neurofibromatosis. The emergence of glandular structures in MPNST is curious and enigmatic. We report a case of recurrent MPNST with glandular differentiation arising in the background of neurofibroma in a 20-year-old lady. By immunohistochemistry, MPNST showed focal positive staining for S100 and negative staining for SOX10 while adjacent neurofibroma showed diffuse positivity for S100 and SOX10. The glandular tumor cells showed positive staining for CDX2, Cam5.2, CK19, and CK7 (focal), while negative for SOX10 and S100. MPNST with glandular differentiation is quite rare which may pose a diagnostic challenge. The glandular differentiation in MPNST should be excluded from the metastasis from second primary with the aid of clinical and radiological correlation.

Malignant Gastrointestinal Neuroectodermal Tumor of Small Intestine Showing DOG1 Expression: A Case Report and Review of Literature.

Malignant gastrointestinal neuroectodermal tumor (GNET), also referred to as clear cell sarcoma-like tumor of the GI tract is a rare mesenchymal tumor of the gastrointestinal tract. It has to be distinguished from various mimickers including gastrointestinal stromal tumor (GIST) due to its aggressive course and different natural history and therapeutic approach. Here we report a case of GNET arising in the small intestine with aberrant DOG1 expression posing a diagnostic challenge. In this context, the combination of clinical, histomorphological, immunohistochemical, and molecular features helped to establish a proper diagnosis.

Signet ring cell carcinoma of the rectal stump in a known ulcerative colitis patient.

Colorectal carcinoma (CRC) is the third most commonly diagnosed cancer worldwide and is the second most common cause of cancer-related deaths. However, the Omani population shares the major burden as the most prevalent carcinoma. The disease is comparatively higher in males than females. Patients with pre-existing risk factors, including inflammatory bowel disease, are at increased risk of developing neoplasia. Among the various histopathological subtypes of adenocarcinoma in the rectum, signet ring cell carcinoma is the rarest and accounts for approximately 1% of the cases. Given the aggressive nature of this tumor, advanced presentation, stage, and poor prognosis, regular endoscopic surveillance is essential. Hereby, we report a rare case of signet ring cell carcinoma arising in the rectal stump in an already diagnosed and operated patient of Ulcerative colitis.

Signet ring cell carcinoma of the rectal stump in a known ulcerative colitis patient

ABSTRACT Colorectal carcinoma (CRC) is the third most commonly diagnosed cancer worldwide and is the second most common cause of cancer-related deaths. However, the Omani population shares the major burden as the most prevalent carcinoma. The disease is comparatively higher in males than females. Patients with pre-existing risk factors, including inflammatory bowel disease, are at increased risk of developing neoplasia. Among the various histopathological subtypes of adenocarcinoma in the rectum, signet ring cell carcinoma is the rarest and accounts for approximately 1% of the cases. Given the aggressive nature of this tumor, advanced presentation, stage, and poor prognosis, regular endoscopic surveillance is essential. Hereby, we report a rare case of signet ring cell carcinoma arising in the rectal stump in an already diagnosed and operated patient of Ulcerative colitis.

Immuno-Histochemical Assessment of HER2NEU Expression in Gastric Adenocarcinoma in North Karnataka, India

Background and Objectives: Gastric cancer is the fourth most common cancer worldwide and ranks fifth in India. Surgical resection is curative in early stage gastric cancers. Most of the gastric cancers are diagnosed at an advanced stage necessitating multimodality treatment strategies. Based on the ToGA trial, the international regulatory agencies have recently approved trastuzumab in locally advanced and metastatic gastric and gastroesophageal adenocarcinomas expressing HER2. Since there are limited studies from India and no published data available from this part of North Karnataka, we undertook this study to evaluate the frequency of expression of HER2 in gastric and gastroesophageal adenocarcinomas and to correlate it with various clinicopathological variables. Methodology: The study was conducted in the Department of Pathology, SDM College of Medical Sciences and Hospital, Dharwad, Karnataka from May 2012 to January 2016. The samples included both endoscopic biopsies and gastrectomies. Histopathological slides from 70 cases were reviewed. Immunohistochemical staining for HER2 was performed in all the cases and Hoffman's gastric cancer scoring system was employed. The results of HER2 expression was correlated with various clinicopathological parameters. Results: HER2 positivity was seen in 16/70 cases (23%). 6 cases (8.5%) were equivocal and 48/70 cases (68.5%) were HER2 negative. HER2 positivity was more common in GEJ cancers and intestinal type of adenocarcinoma. However, it did not correlate with age, gender, grade and stage. Conclusion: HER2 positivity was noted in 23% of the cases. 23.4% of intestinal type and 21.7% of diffuse type were HER2 positive. HER2 positivity did not significantly depend on age, gender, tumour type, grade and stage. Hence, HER2 remains as an independent biomarker and should be tested in all patients of gastric cancer regardless of the clinicopathological findings for offering a personalized treatment.