Most sRCC research focuses on advanced or metastatic disease, with limited studies analyzing localized non-metastatic patient outcomes. This study evaluates post-nephrectomy outcomes and predictors of cancer-specific survival (CSS) between localized sRCC and grade-4 RCC (non-sRCC) patients.
564 localized RCC patients underwent partial or radical nephrectomy between June 1988 to March 2019 for sRCC (n=204) or WHO/ISUP grade-4 non-sRCC (n=360). CSS at every stage between groups were assessed. Phase-III ASSURE clinical trial data was used to externally validate CSS findings. Man-Whitney U, Chi-squared tests compared outcomes and Kaplan-Meier method evaluated CSS, overall survival (OS) and recurrence-free survival. Clinicopathologic features associated with RCC death were evaluated using Cox-proportional hazards regression.
Median follow-up was 31.5 months. Median OS and CSS between sRCC and grade-4 non-sRCC groups was 45 vs 102 months and 49 vs 152 months, respectively, p<0.001. At every stage, sRCC had worse CSS compared to grade-4 non-sRCC. Notably, pT1 sRCC had worse CSS than pT3 grade-4 non-sRCC. Negative predictors of CSS were sarcomatoid features, non-clear cell histology, positive-margins, higher stage (pT3/pT4) and use of minimally-invasive surgery (MIS). ASSURE external verification showed worse CSS in sRCC patients (HR 1.63 (95% CI [1.12-2.36]), p=0.01), but not worse outcomes in MIS surgery (HR 1.39 (95% CI [0.75-2.56]), p=0.30).
Localized sRCC has worse CSS compared to grade-4 non-sRCC at every stage. Negative survival predictors included positive-margins, higher pathological stage, use of MIS, and non-ccRCC histology. sRCC is an aggressive variant even at low stages requiring vigilant surveillance and possible inclusion in adjuvant therapy trials.
BJU international. 2023 Aug 17 [Epub ahead of print]
Kyle A Blum, Andrew W Silagy, Andrea Knezevic, Stanley Weng, Alan Wang, Roy Mano, Julian Marcon, Renzo G DiNatale, Alejandro Sanchez, Satish Tickoo, Sounak Gupta, Robert Motzer, Naomi B Haas, Se Eun Kim, Robert G Uzzo, Jonathan A Coleman, A Ari Hakimi, Paul Russo
Urology Service, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY., Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY., Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY., Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY., Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA., Department of Data Science, Dana Farber Cancer Center, Boston, MA., Department of Surgical Oncology, Division of Urology and Urologic Oncology, Fox Chase Cancer Center, Philadelphia, PA.