Design of an immunohistochemistry biomarker panel for diagnosis of pancreatic adenocarcinoma.

BACKGROUND: Challenges still exist in differentiating pancreatic adenocarcinoma from benign disease. The use of adjuvant testing of tissue biopsies has demonstrated potential diagnostic value. We designed a proof of concept study to first validate four individual immunohistochemistry biomarkers and then combine them into a panel to boost overall diagnostic sensitivity. METHODS: Malignant and benign pancreas from 27 pancreaticoduodenectomy specimens underwent immunohistochemistry staining with VHL, IMP3, S100A4, S100P. Using ROC curve analysis, threshold criteria for number of cells staining were chosen for each biomarker. Biomarkers were then evaluated as a panel for their ability to discriminate malignant from benign specimens. RESULTS: Diagnostic sensitivity of VHL, IMP3, S100A4, and S100P were 75.0%, 79.2%, 45.8%, and 0%. When VHL, IMP3, and S100A4 were grouped into a panel, they were able to distinguish cancer from normal tissue with a sensitivity of 100% and a specificity of 96%. CONCLUSIONS: The high diagnostic value of an IHC panel consisting of VHL, IMP3, and S100A4 on surgical specimens suggests the need for future prospective studies of these biomarkers on biopsy specimens.

Locally aggressive and multicentric recurrent extraocular sebaceous carcinoma: case report and literature review.

OBJECTIVE: Sebaceous Carcinoma is a rare and aggressive malignant tumor. We present a case report of a large truncal tumor with multicentricity and aggressive locoregional recurrence that required trapezius myocutaneous flap reconstruction. Examining patterns of multicentricity, metastasis, and recurrence of sebaceous carcinoma in the literature we sought to explore potential reasons behind the aggressive behavior. METHODS: Retrospective chart review was used to analyze the case in detail. Preoperative workup, intraoperative details, pathology, and follow-up visits were reviewed. Selected literature was considered with series of 5 or more patients. RESULTS: The recurrent tumor was resected with negative margins leaving a defect of 14 × 7 cm(2) that was covered with a trapezius myocutaneous flap. Postoperative hospital course was uneventful with no further local recurrence. On follow-up visits, tumors at other sites have been discovered. Reported rates of multicentricity, metastasis, and recurrence vary widely in the literature, but both subtypes of sebaceous carcinoma behave aggressively. CONCLUSIONS: A combination of genetic predisposition, delayed definitive care, and inherent tumor biology led to the aggressive locoregional disease in this case.

Malignant granular cell tumor of the thigh.

Malignant granular cell tumor is a rare neural tumor characterized by abundant granular-appearing tumor cells. These tumors account for <2% of all granular cell tumors. Unlike its benign counterpart, a malignant granular cell tumor presents primarily in the lower limb and is notably larger. Both the uncommon occurrence of malignant granular cell tumors and its similarities in feature with their benign counterparts make diagnosis of this particular malignancy difficult. By 1998, Fanburg-Smith et al developed a diagnostic criteria in which granular cell tumors were divided into 3 categories-benign, atypical, and malignant-based on 6 histological characteristics of the tumor: necrosis, spindling, vesicular nuclei with large nucleoli, increased mitotic activity, high nuclear-to-cytoplasmic ratio, and pleomorphism. This article presents a case of a large malignant granular cell tumor in the right thigh of a 69-year-old woman. Gross examination of the mass showed the well-demarcated, tan, white tumor measuring 18.2 cm long and 7.6 cm wide at its largest width. Histological examination of the mass, performed by an oncological pathologist, demonstrated foci of tumor necrosis, scattered apoptotic cells, prominent nucleoli, increased nuclear-to-cytoplasmic ratio, increased mitotic activity, and areas of spindling with significant atypia. To our knowledge, this is the largest reported case of malignant granular cell tumor in the lower limb diagnosed using the histological criteria established by Fanburg-Smith et al. This case stresses the importance of thorough evaluation in instances of atypical granular cell tumor presentations.