Viren Patel

Collecting Duct Renal Cell Carcinoma Found to Involve the Collecting System During Partial Nephrectomy: A Case Report

Collecting duct carcinoma (CDC) is a rare and aggressive form of renal cell carcinoma (RCC) arising from the principal cells of the collecting duct. One third of cases present with metastatic disease, but many present in a manner similar to conventional RCC or urothelial carcinoma (UC). We discuss a case of CDC which presented as a small mass at the cortico-medullary junction, and was discovered at robotic partial nephrectomy (RPN) to be grossly involving the collecting system. A 62-year-old man presented with a small renal mass suspicious for RCC, which was found on computed tomography (CT) after an episode of gross hematuria. After thorough workup, RPN was attempted; however, intraoperatively the mass was found to be involving the collecting system. Radical nephroureterectomy was performed, and the pathology report revealed CDC. CDC is a rare and aggressive form of RCC. While many cases are metastatic at diagnosis, most patients present with the incidental finding of a small renal mass. There are no reports of a CDC involving the collecting system at RPN after negative ureteroscopy preoperatively. The adjuvant therapeutic options for CDC are limited, and long term survival is poor.

Aggressive Subcutaneous Panniculitis-Like CD30+ Peripheral T-Cell Lymphoma with Diffuse EBER Expression.

T-cell lineage lymphoma with an intense membranous and paranuclear CD30 expression in the absence of ALK1 raises a differential diagnosis of peripheral T-cell lymphoma (PTCL), NOS and anaplastic large cell lymphoma (ALCL), ALK negative. However, Epstein-Barr virus is consistently negative in ALCL and is not considered an implicating factor in its pathogenesis. We describe a case of T-cell lymphoma showing anaplastic large cell morphology with scattered hallmark cells and a uniform CD30 and Epstein-Barr virus encoded early RNA (EBER) expression that primarily involved the subcutaneous tissue at presentation. On incisional biopsy, the neoplastic cells were positive for CD3, CD2, and CD30 while negative for LCA, CD20, PAX5, CD56, ALK1, and cytotoxic granules. Molecular analysis identified a positive T-cell receptor (beta and gamma) gene rearrangement by PCR. Proliferation index approached 100% and the patient had a rapidly progressive course; the subcutaneous lesions more than doubled in size within couple of weeks with new evidence for widespread systemic involvement. This case emphasizes a rare EBV association with a CD30 positive T-cell lymphoma where the morphologic and immunophenotypic findings are otherwise nondiscriminatory between PTCL, NOS and ALCL, ALK negative.