Pin Tu

Renal cell carcinomas with t(6;11)(p21;q12): A clinicopathologic study emphasizing unusual morphology, novel alpha-TFEB gene fusion point, immunobiomarkers, and ultrastructural features, as well as detection of the gene fusion by fluorescence in situ hybridization

Renal cell carcinomas (RCCs) with t(6;11)(p21;q12) are extremely rare and characterized by specific chromosome translocation, involving the transcription factor EB (TFEB). Fewer than 30 cases have been described in the literature. We examined 7 additional cases of this rare tumor by clinicopathologic, immunohistochemical, molecular, and ultrastructural analyses. Four tumors had the typical morphologic features of TFEB RCCs, whereas 3 cases demonstrated uncommon morphologic features, mimicking epithelioid angiomyolipoma, chromophobe cell RCC, and clear cell RCC, respectively. Immunohistochemically, aside from TFEB and cathepsin K, kidney-specific cadherin was another sensitive and relatively specific marker for TFEB RCCs, supporting a distal nephron origin for these renal tumors. We also observed different ultrastructures including mitochondrion with areas of lipofuscin pigment in the smaller cells in these cases. An identical Alpha-TFEB fusion gene, 486 bp, was identified in 2 cases. In addition to the polymerase chain reaction method, we also developed a fluorescence in situ hybridization assay to serve as a cost-effective and time-efficient diagnostic tool. We detected a TFEB gene rearrangement in all 7 cases using the fluorescence in situ hybridization method. TFEB RCC seemed to be an indolent tumor. During a mean follow-up of 31 months, none of the cases developed tumor recurrence, progression, or metastasis.

Cathepsin K expression in a wide spectrum of perivascular epithelioid cell neoplasms (PEComas): a clinicopathological study emphasizing extrarenal PEComas.

Recent studies have demonstrated that cathepsin K seems to be a powerful marker in identifying renal perivascular epithelioid cell neoplasms (PEComas). However, the expression in extrarenal PEComas has not been well characterized due to their rare incidence. Our aim was to investigate the expression of cathepsin K in a wide spectrum of extrar‐enal PEComas and evaluate its potential diagnostic usefulness in comparison with other commonly used markers.

Ovarian small-cell carcinoma hypercalcemic type successfully treated: a case report and literature review.

Ovarian small-cell carcinoma hypercalcemic type (OSCCHT) is a relatively rare and highly fatal gynecological malignancy. Prognosis is generally poor, and no treatment guidelines are offered. Here, we report a case of OSCCHT successfully treated by complete excision and a postoperative chemotherapy scheme of carboplatin and paclitaxel. A 29-year-old female with with pelvic mass and significantly increased serum calcium (4.90 mmol/L) was referred to our hospital on August 22, 2013. Abdominal ultrasonography and computed tomography revealed a pelvic nonhomogeneous echo of a 113×102 mm mass, possibly coming from the adnexa of the uterus. Preoperative examinations indicated high levels of serum calcium and relevant acute renal dysfunction; hence, continuous renal replacement therapy was performed until all tests reached minimum operation requirements. Interestingly, after excision, serum calcium levels decreased rapidly and therefore, extra calcium had to be taken in order to take the level back up to normal. The patient was diagnosed with OSCCHT based on the clinical data and pathological examinations. After six cycles of chemotherapy, the patient was in a good condition and on follow-up there were no signs of recurrence.