5%), haematological malignancies (n = 3; 7%), skin carcinoma (n = 3; 7%) and thyroid cancer (n = 1; 2.5%). The majority of GISTs occurred in stomach (64%) and small intestine (31%), with rare occurrence in rectum (2.5%) or esophagus (2.5%). In 78%, GIST were asymptomatic and were accidentally found during diagnostic or therapeutic procedures for associated malignancies. GIST’s size ranged from 0.1 cm to 9 cm (mean size: 2.3 cm) and all of them FK866 concentration had a low (<5/50 HPFs) or no mitotic rate. CD117 was expressed in 84% and CD34 in 67%. Thirty tumors (84%) were of no- very low- or low-risk and six tumors of intermediate. Imatinib

mesylate was administered to 2 patients. During follow-up (range 3–140 months, mean: 62 months), one patient suffered from distant metastases of GIST. Seven patients (19%) died of associated malignancies and three patients (8%) of other non-tumor-associated cause, but noone died of GIST. Conclusion: The coexistence of GIST with other malignancies is higher than Dabrafenib mw previously reported and should draw attention of clinicians towards these incidental findings. Little

is known about the possible common origin of GIST and associated malignancies. The prognosis in these patients is usually determined by the other malignancy and not significantly influenced by the GIST. Therefore treatment algorithms should be focused on the prognostically relevant malignancy. Key Word(s): 1. GIST; 2. malignancy; 3. imatinib mesylate; 4. coexistence; Presenting Author: HUAN-FA HSIEH Additional Authors: CHENG-HSIANG HSU, CHI-TIEN LIU, WAI-SANG KUAN Corresponding Author: HUAN-FA HSIEH Affiliations: Yeezen General Hospital Objective: Neuroendocrine tumor (NET) of gastrointestinal tract is a very rare, difficult

and confusing tumor to diagnosis, particularly in early asymptomatic stage. The nomenclature is also complicated until 2010 when WHO divided the NETs into 5 categories: well-differentiated endocrine tumors (Grade 1, carcinoid), well-differentiated (Grade 2) endocrine carcinomas, poorly-differentiated endocrine (grade 3, small cell) carcinomas, mixed endocrine-exocrine tumors, and tumor like lesions. Gastrointestinal stromal tumor (GIST) is also a very rare and relatively click here new diagnostic entity that has been the focus of considerable clinical and laboratory research in the last 10 years. Both NET and GIST are usually subclinical and asymptomatic when they are small-sized. Herein we report a case with perforated peptic ulcer (PPU) who had these two extremely rare tumors coexisting near the gastric pylorus. Methods: This 80-year-old male who had long-term history of NIDDM, HCVD, PUD and cervical spondylosis, underwent emergently exploratory laparotomy for PPU with hemorrhage. Hemigastrectomy with Billroth No-II anastomosis and tube duodenostomy was carried out due to markable deformity of pylorus and a 2-cm blowout perforation at duodenal bulb.