Aberrant Cytoplasmic INSM1 Expression in Erythroid Cells: A Potential Diagnostic Pitfall Versus Neuroendocrine Neoplasms.

Insulinoma-associated protein 1 (INSM1) is a relatively new immunostain used in the diagnostic assessment of tumors with neuroendocrine differentiation. While INSM1 positivity has been described in some non-neuroendocrine neoplasms, reactivity in red blood cells (RBCs) has only been anecdotally noted in one prior study without description of the degree/extent of staining. INSM1 staining in nucleated erythroid precursors has not been previously reported.

MAPK1IP1L::TFE3-rearranged renal cell carcinoma: a novel fusion adding to the differential diagnosis of oncocytic renal neoplasms.

Beyond the more common TFE3 fusion partners PRCC, ASPSCR1, and SFPQ, additional less common fusion partners of TFE3-rearranged renal cell carcinoma (RCC) have been described. Herein, we present an example of TFE3-rearranged renal cell carcinoma harboring fusion partner MAPK1IP1L, a rare rearrangement with only one other reported tumor found in the literature. The currently reported TFE3-rearranged RCC demonstrates unique histological features compared to the previously reported tumor including dense eosinophilic cytoplasm and nuclear pseudoinclusions (corroborated by electron microscopic evaluation), with features not typically seen in other TFE3-rearranged RCCs.

Incidence and Pitfalls of Adipose Tissue Encountered in Prostatic Transurethral Resections and Related Specimens.

While the presence of adipose tissue and its involvement by prostatic cancer (extraprostatic extension) is well-recognized in prostate biopsies, adipose tissue in transurethral resections of the prostate (TURP) is largely unexplored. Herein, 200 consecutive TURPs and related specimens were reviewed, including a separate 3-year analysis of specimens containing prostatic cancer, with the following data collected: presence of fat, presence of cancer within fat, and quantity of fat. For specimens with both fat and prostatic cancer, specimen weight and tumor volume were recorded.

The stratification of positive lymph nodes into pN1 and pN2 for upper urinary tract carcinoma is not prognostically significant.

The 3-7 edition of the American Joint Committee on Cancer had 3 categories for positive lymph nodes (pN1-3) in upper urinary tract carcinomas. The 8th edition removed pN3, defining pN1 as one lymph node with a tumor deposit ≤2 cm and pN2 as a node with a tumor deposit >2 cm or metastases in multiple nodes. The aim of this study was to assess if the current pN categories impact survival in renal pelvic and ureteral carcinomas.

Renal Pelvic Urothelial Carcinoma With Invasion Into Renal Medulla Can Be Redefined as pT2 to Improve Correlation With Survival.

According to the American Joint Cancer Committee, pT3 renal pelvic carcinoma is defined as tumor invading the renal parenchyma and/or peripelvic fat and is the largest pT category, with notable survival heterogeneity. Anatomical landmarks within the renal pelvis can be difficult to discern. Using glomeruli as a boundary to differentiate renal medulla invasion from renal cortex invasion, this study aimed to compare patient survival of pT3 renal pelvic urothelial carcinoma on the basis of the extent of renal parenchyma invasion and, thereafter, determine whether redefining pT2 and pT3 improves pT correlation with survival.