Histomorphological spectrum of gastrointestinal stromal tumors: an institutional experience

Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the abdominal area. They can involve any portion of the gastrointestinal (GI) tract, omentum, mesentery, retroperitoneum, and other sites. They form 1-2% of the histologic types of gastrointestinal tract tumors. Aims and objectives were to analyze and correlate morphological, clinical and histomorphology features of gastrointestinal tumors presenting at different sites. Methods: This was a retrospective observational study for six years. Medical records of the histopathologically diagnosed GIST cases were reviewed for patient demographics and clinical presentation, and tumor findings were noted. Results: Of the 28 patients, ages ranged from 28 to 80 years. Symptoms ranged from abdominal pain, epigastric discomfort, mass, upper/lower gastrointestinal bleeding, rectal bleeding, anemia, weight loss, and small bowel obstruction. Sites involved were the small bowel, stomach, mesentery, rectum, duodenum, greater omentum, and retroperitoneum. Of 28 cases of GIST, 25 cases showed both c-KIT and DOG-1 positivity, 1 case showed only c-KIT positivity, 1 case showed only DOG-1 positivity, and 1 case was both c-KIT and DOG-1 negative. Conclusions: GISTS are unpredictable mesenchymal tumors. Common sites are the stomach and small gut. Mesenteric and omental GIST are rare. Spindle cell morphology was more commonly present.

Controlled drug release studies of valsartan using differently sulfonated methacryloxyacetophenone and methyl methacrylate co-polymer resins as drug carriers.

2-methacryloxyacetophenone (MAP) was prepared and subjected to suspension polymerization with methyl methacrylate (MMA) using benzoylperoxide (BPO) as free radical initiator. The differently sulfonated MAPMMA cross-linked copolymer cationic exchange resins were prepared by sulfonation with concentrated sulphuric acid at 70oC. Several characteristics of the prepared resins were evaluated, i.e. FT-IR, the Ion-exchange capacity (IEC), Swelling studies, Particle size distribution and Microscopic morphology. The resin characteristics were altered with degree of sulfonation, providing that differently sulfonated resins could be prepared. The behavior of valsartan (VLN) loading and in vitro release in the USP stimulated gastric and intestinal fluids of the obtained resins were evaluated. The drug loaded in the resin increased with increasing degree of sulfonic group and hence the drug binding site in resin employed. The drug release was lower from the resins with higher degree of sulfonic group due to the increase in the diffusive path depth. The drug release was a little lower in stimulated gastric fluid (SGF) than stimulated intestinal fluids (SIF). The basic group, ionized to a little greater extent in SGF and preferred binding with the resin rather than releasing. Hence, the differently sulfonated resins could be utilized as novel carriers for drug delivery.