Behcet's Disease Mimicking Crohn's Disease: A Diagnostic Pitfall in GI Tract Biopsies.

Behcet's disease is a rare entity. It's a multi-systemic inflammatory disease of unknown etiology characterized by recurrent ulcers and vasculitis, mainly including the oral cavity, eyes, gastrointestinal tract and joints. Crohn's disease is a chronic inflammatory disorder that may affect the same organs as Behcet's disease, however more frequently the gastrointestinal tract. Distinguishing Behcet's disease from Crohn's disease can be challenging due to the overlapping clinical presentation and similar morphology features on pathology biopsy specimens. This is a case report of a 32-year-old female who first presented at the emergency department with fatigue, weight loss, arthralgia, and erythema nodosum. The patient was admitted for oral ulcers, skin rash, genital ulcers, and melena one month later. Treatment with prednisone was started at the time and further workup for Behcet's disease versus inflammatory bowel disease was started. Her esophagus biopsy shows granulomatous-like vasculitis, and her colon biopsies show overlapping features with Crohn's disease. Herein, we present a rare and interesting case in which Behcet's disease mimics inflammatory bowel disease on the gastrointestinal tract biopsies but with some unique findings and diagnostic pitfalls for gastrointestinal tract vasculitis and ulceration.

Perivascular epithelioid clear cell tumor of the common bile duct.

The perivascular epithelioid clear cell tumor (PEComa) has been described in a number of locations, including the pancreas, uterus, bladder, prostate, and gastrointestinal tract. We report the existence of a similar tumor occurring in the distal common bile duct of a 51-year-old man admitted for obstructive jaundice. The tumor had characteristic histologic features of a PEComa, including a richly vascular organoid architecture, tumor cells with clear to lightly eosinophilic cytoplasm, and variably prominent nucleoli. Immunohistochemically, the tumor cells were positive for HMB-45 and neuron specific enolase but negative for epithelial markers, smooth muscle markers, other neuroendocrine markers, vimentin, melan-A, and S-100 protein. PEComas appear to be ubiquitous tumors with characteristic histology and immunophenotype. Although most of these tumors have behaved in a benign fashion, they should be considered tumors of uncertain malignant potential given previous reports of recurrence and metastases. During a short follow-up period following a conservative local excision, our patient remains free of disease.

Pelvic washing cytology in serous borderline tumors of the ovary using ThinPrep: are there cytologic clues to detecting tumor cells?

The detection of tumor cells in pelvic washings of patients with serous borderline tumors of the ovary (SBT) remains a diagnostic challenge. Accurate diagnosis of pelvic washings is important in determining therapeutic regimens and assessing patient prognosis. No study has exclusively examined pelvic washing cytology of patients with SBT using only ThinPrep methodology. The purpose of this study is to examine whether cytologic clues exist in detecting tumor cells of SBT in pelvic washings processed with ThinPrep. Using previously established criteria, we reviewed the pelvic washes of 37 patients with SBT and correlated them with the histologic findings in the omentum. We also compared their cytoarchitectural features with pelvic washes in patients with benign ovarian disease and serous carcinoma. Cytoarchitectural features that achieved statistical significance in distinguishing cells of a SBT from reactive mesothelial cells include the following findings: presence of a two-cell population (P = 0.001), psammoma bodies (P = 0.001), cytoplasmic vacuolization (P = 0.001), smooth group contours (P = 0.004), nuclear size >2x neutrophils (P = 0.004), high nuclear-to-cytoplasmic (N/C) ratio (P = 0.004), absent intercellular windows (P = 0.007), and course nuclear chromatin (P = 0.032). Psammoma bodies were the only statistically significant feature distinguishing SBT from serous carcinoma, being more common in SBT than serous carcinoma (P = 0.035). The prominent number of associated psammoma bodies seen in the SBT group was a notable finding that may aid as a valuable cytologic clue in detecting tumor cells. Overall cellularity remains a source of false-negative diagnosis. Correlation with histologic findings remains crucial given our inability to reliably distinguish tumor cells of SBT from endosalpingiosis or serous adenocarcinoma.