Renal Neoplasms with Concurrent Castleman-Like Regional Lymphadenopathy.

INTRODUCTION: Renal cell neoplasms are known to be associated with paraneoplastic syndromes, and the association with Castleman-like regional lymphadenopathy has been rarely reported. We aim to characterize the association between renal neoplasms and Castleman-like lymphadenopathy. METHODS: A search for renal neoplasms with concurrent Castleman-like lymphadenopathy in one single medical institution from 2000 to 2023 resulted in 4 specimens. A literature search for "Castleman" and "renal neoplasm" resulted in 8 reports. Patients' demographics, clinical presentation, gross and histologic features, results of ancillary studies, treatment, and follow-up were evaluated. RESULTS: Our patients included 3 men and 1 woman, with a mean age of 60 years. Four different subtypes of renal neoplasms were diagnosed, including clear cell renal cell carcinoma (RCC), papillary RCC, chromophobe RCC, and mucinous cystadenoma of the renal pelvis. For Castleman-like regional lymphadenopathy, 2 were plasma-cell predominant, and 2 were hyaline-vascular. After a median follow-up of 84 months, all patients were alive with no recurrence or progression of Castleman-like features following nephrectomies. CONCLUSION: Castleman-like regional lymphadenopathy should be considered in patients with renal tumors and lymphadenopathy. Although more prevalent in clear cell RCC, it can be also associated with other renal neoplasms. The concurrent lymphadenopathy was remitted following the renal tumor resections.

Optimal Method for Reporting Prostate Cancer Grade in MRI-targeted Biopsies.

When multiple cores are biopsied from a single magnetic resonance imaging (MRI)-targeted lesion, Gleason grade may be assigned for each core separately or for all cores of the lesion in aggregate. Because of the potential for disparate grades, an optimal method for pathology reporting MRI lesion grade awaits validation. We examined our institutional experience on the concordance of biopsy grade with subsequent radical prostatectomy (RP) grade of targeted lesions when grade is determined on individual versus aggregate core basis. For 317 patients (with 367 lesions) who underwent MRI-targeted biopsy followed by RP, targeted lesion grade was assigned as (1) global Grade Group (GG), aggregated positive cores; (2) highest GG (highest grade in single biopsy core); and (3) largest volume GG (grade in the core with longest cancer linear length). The 3 biopsy grades were compared (equivalence, upgrade, or downgrade) with the final grade of the lesion in the RP, using κ and weighted κ coefficients. The biopsy global, highest, and largest GGs were the same as the final RP GG in 73%, 68%, 62% cases, respectively (weighted κ: 0.77, 0.79, and 0.71). For cases where the targeted lesion biopsy grade scores differed from each other when assigned by global, highest, and largest GG, the concordance with the targeted lesion RP GG was 69%, 52%, 31% for biopsy global, highest, and largest GGs tumors (weighted κ: 0.65, 0.68, 0.59). Overall, global, highest, and largest GG of the targeted biopsy show substantial agreement with RP-targeted lesion GG, however targeted global GG yields slightly better agreement than either targeted highest or largest GG. This becomes more apparent in nearly one third of cases when each of the 3 targeted lesion level biopsy scores differ. These results support the use of global (aggregate) GG for reporting of MRI lesion-targeted biopsies, while further validations are awaited.

Unusual BK polyomavirus-associated urologic malignancies in renal transplant recipients: Report of two cases and review of the literature.

Renal transplant recipients are at increased risk of developing urologic malignancies, some of which are associated with prolonged BK virus infection. We report two cases of BK virus-associated carcinoma with variant morphological patterns (clear cell adenocarcinoma of the bladder and micropapillary urothelial carcinoma of the pelvicaliceal system) arising in the urinary tract of renal transplant recipients. In both cases, the diagnosis was initially established on cytologic specimens: on urine cytology in one patient and on fine needle aspiration of an inguinal lymph node in the other patient. The unusual cytologic features of both cases (multiple morphologies in one patient and micropapillary pattern in the other), co-occurrence of decoy cells in the urine of one patient and the occurrence of these tumors in renal transplant recipients raised the possibility of BK polyomavirus-associated malignancy and led to confirmatory SV40 immunostains that were positive. These cases expand the morphologic variants of BK virus-associated urologic malignancies diagnosed in solid organ transplant patients. While differentiating BK virus-infected cells from malignant cells in urine cytology specimens is a diagnostic challenge, greater awareness of their possible co-existence is vital, as this could be the only chance for an early diagnosis.