[Clinicopathologic and molecular characteristics of malignant gastrointestinal neuroectodermal tumors].

Objective: To investigate the clinicopathologic and molecular characteristics, diagnostic, differential diagnostic and prognostic features of malignant gastrointestinal neuroectodermal tumor. Methods: Two cases of malignant gastrointestinal neuroectodermal tumor were retrieved; the clinical and radiologic features, histomorphology, immunophenotype, molecular genetics and prognosis were analyzed and the relevant literature reviewed. Results: Case 1 was a 57-year-old male, presented with recurrent abdominal pain and melena. Pelvic imaging showed a circumscribed thickening of the wall of a small intestinal segment, and a malignant lymphoma was favored. Case 2 was a 24-year-old male, presented with recurrent small intestinal malignancy. Imaging demonstrated multiple masses in the peritoneal and pelvic cavities, and a malignant gastrointestinal stromal tumor with multiple metastases was suspected. Grossly both tumors were located mainly in the muscularis propria of small intestine. Case 1 showed a single 5.5 cm tumor; and case 2 consisted of two tumors measuring 4 cm and 6 cm respectively. Microscopic examination of both tumors showed small round blue, but focally spindled or clear tumor cells in solid pattern. The tumor cells had scanty cytoplasm, indistinctive nucleoli and brisk mitoses. Osteoclast-like giant cells were dispersed within the stroma. In case 1 rosette-like and pseudo-papillary growth patterns were noted, and in case 2 there were variable-sized hemorrhagic cysts. By immunohistochemistry, both tumors showed strong and diffuse expression of SOX10 and S-100, and focal to diffuse expression of neuroendocrine markers (CD56 or synaptophysin). Case 2 exhibited focal reactivity to pan-cytokeratin. Both tumors lacked expression of markers associated with gastrointestinal stromal tumor, smooth muscle tumor, melanoma (HMB45 or Melan A), dendritic cell tumor and Ewing sarcoma. Fluorescence in situ hybridization analysis demonstrated EWSR1 rearrangement in both tumors and the next generation sequencing confirmed EWSR1-ATF1 gene fusion in case 2. At follow-up of 16 months, case 1 was recurrence or metastasis free; whereas case 2 showed multiple recurrences and metastases within 19 months although stable disease was transiently achieved when treated with combinations of multidrug and targeted chemotherapy. Conclusions: Malignant gastrointestinal neuroectodermal tumor is a rare and aggressive soft tissue sarcoma with a predilection for small intestine. It has distinctive morphologic, immunohistochemical and molecular characteristics and needs to be distinguished from other small blue round and spindle cell tumors that occur in the gut. Careful attentions to its characteristic histomorphology with the judicious use of immunohistochemistry and molecular genetics can help to distinguish this tumor from its many mimickers.

Ultrasound diagnosis in gynecological acute abdomen.

As ultrasound diagnosis is applied more frequently in gynecological acute abdomen, we carried out this study to discuss the diagnosis of endometriosis with ultrasound imaging and analyze the efficacy of microRNA used for diagnosing endometriosis and evaluating prognosis by comparing differentially expressed microRNA in subjects with or without endometriosis. Ultrasound examination results and clinical pathological examination results of 60 cases of gynecological acute abdomen were compared. Blood samples were collected from patients with endometriosis. Of 60 cases, 38 cases recurred in 20 months after surgery and the remaining 22 cases had no recurrence in the 30-month follow-up. Additionally, blood was collected from 40 patients without endometriosis as control. Then total RNA was extracted from these blood samples to determine the difference of expression of microRNA (miR-17-5p, miR-20a, miR-199a and miR-141). Compared to healthy subjects, the endometriosis patients showed significantly increased expression of miR-199a, but the expression of miR-17-5p, miR-20a and miR-141 had an obvious decrease; the differences were statistically significant (p less than 0.01). For recurred cases, miR-199 showed a remarkably high expression and miR-17-5p and miR-20a expressed significantly low.