Hepatic Uterus-Like Mass Misdiagnosed as Hepatic Abscess

Background. Hepatic endometriosis/uterus-like mass is rare and may be overlooked during hepatic cyst workups. We report a case of uterus-like mass, misdiagnosed as hepatic abscess. Case Report: A 47-year-old woman developed abdominal pain and vomiting. Infectious colitis with hepatic abscess was diagnosed, and remained antibiotic-refractory. Fine-needle aspiration and core biopsies showed benign contents. The patient presented to our institution with symptoms and normal blood work. Laparoscopic excision demonstrated a 1.4-cm cyst composed of endometrial glands (estrogen receptor+ and progesterone receptor+) and stroma (CD10+) with smooth muscle actin (SMA+), arranged in an organoid fashion. The patient, status-post hysterectomy, had no history or symptoms of endometriosis. Conclusion. This rare case illustrates the merit of considering uterus-like mass/endometriosis in the differential diagnosis of antibiotic-refractory hepatic cysts. Cyst heterogeneity may confound needle biopsy. We report the first instance of a hepatic uterus-like mass, with a review of related entities, postulated histogenesis, and important clinical associations

Diagnostic and therapeutic implications of a novel immunohistochemical panel detecting duodenal mucosal invasion by pancreatic ductal adenocarcinoma

Background: We investigated a series of pancreaticoduodenectomy and duodenal biopsies with a panel of immunohistochemical markers to identify duodenal mucosal invasion by pancreatic ductal adenocarcinoma (PDAC), including markers of poor prognosis and targets of promising novel immunotherapies. Materials and Methods: Eighteen consecutive pancreaticoduodenectomy specimens with duodenal mucosal invasion by PDAC were examined for expression of MUC1, MUC4, MUC5AC, MUC6, mesothelin, MUC2, CDX2, and DPC4 on formalin-fixed, paraffin-embedded sections of duodenal-ampullary-pancreatic junctions. Expression of all but MUC6 was also assessed in duodenal biopsies from 12 patients with duodenal mucosal invasion by PDAC. Results: The duodenal mucosa expressed MUC1 (crypts), MUC2 (goblet cells), MUC6 (Brunner glands), CDX2, and DPC4. PDACs in the duodenal mucosa from the resection (n=16-18) and biopsy (n=12) specimens were marked as follows: MUC1 100% (30/30), MUC4 83% (24/29), MUC5AC 83% (25/30), mesothelin 82% (23/28), MUC2 7% (2/30), and CDX2 36% (10/28). Loss of DPC4 expression was seen in 16 of 29 (55%) cases. Reactive mucosa adjacent to PDAC expressed MUC4, MUC5AC and mesothelin in 65% (17/26), 19% (5/27), and 19% (5/26) of cases, respectively. While MUC5AC and mesothelin had high diagnostic accuracy for detection of PDAC, MUC2, CDX2 and DPC4 expression demonstrated negative correlation with PDAC, with absent expression being highly specific for PDAC. Conclusion: Immunohistochemical labeling for PDAC biomarkers may aid the diagnosis of PDAC in duodenal biopsy, especially in situations where diagnosis of a pancreatic mass is challenging