Does WHO/ISUP grade IV histology provide prognostic insight in chromophobe renal cell carcinoma?


Turan S., Erdem S., Mert S., Cilesiz N. C., Aydinoglu A. T., Balci C.

INTERNATIONAL UROLOGY AND NEPHROLOGY, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1007/s11255-026-05250-w
  • Dergi Adı: INTERNATIONAL UROLOGY AND NEPHROLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, EMBASE, MEDLINE, Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest), Pharma Collection (ProQuest)
  • İstanbul Üniversitesi Adresli: Evet

Özet

Objective Chromophobe renal cell carcinoma (chRCC) is generally considered a less aggressive renal malignancy, yet a clinically meaningful subset displays adverse outcomes. We evaluated the prognostic impact of WHO/ISUP Grade IV histology on cancer-specific survival (CSS) in a large population-based, propensity score-matched cohort. Methods The SEER database (2000-2021) was queried for patients with chRCC. Patients were stratified according to WHO/ISUP grade into Grade IV chRCC and Grade I-III chRCC. The primary endpoint was CSS. A 2:1 nearest-neighbor PSM was performed using age, sex, race, AJCC stage, and tumor size. Fine-Gray competing-risk regression was performed in both the overall and propensity score-matched cohorts. Results A total of 6243 patients with chRCC were identified, including 394 (6.3%) with Grade IV histology. In the overall cohort, Grade IV chRCC was independently associated with worse CSS (HR 2.38, 95%CI 1.78-3.18, p < 0.001). After PSM (n = 1107), this association persisted (HR 1.96, 95%CI 1.43-2.69, p < 0.001) and was supported by competing-risk analysis in both the overall cohort (sHR 2.07, 95% CI 1.53-2.79, p < 0.001) and the matched cohort (sHR 1.80, 95%CI 1.32-2.46, p < 0.001). Conclusion In this large, propensity score-matched, population-based cohort, WHO/ISUP Grade IV chRCC was independently associated with poorer CSS, even after adjustment for tumor burden and stage. These findings should be interpreted within the limitations of registry-defined Grade IV classification.