The following is a summary of “Comparative real-world survival outcomes of metastatic papillary and clear cell renal cell carcinoma treated with immunotherapy, targeted therapy, and combination therapy,” published in the March 2023 issue of Urologic Oncology by Riveros et al.
Numerous studies have provided evidence for innovative therapeutic strategies in metastatic clear cell renal cell carcinoma (ccRCC). However, a significant portion of the information utilized to guide the management of patients with metastatic papillary RCC (pRCC) is derived from the extrapolation of data from ccRCC. Various phase III trials recently substantiated the administration of immunotherapy (IO) and targeted therapy (TT)+IO in ccRCC. However, there needs to be corresponding data available for pRCC. The researchers’ study aimed to elucidate the current patterns of systemic therapy utilization and its effect on the overall survival (OS) of patients diagnosed with metastatic pRCC, using ccRCC as a reference group for comparison. Cases of metastatic papillary renal cell carcinoma (pRCC) and clear cell renal cell carcinoma (ccRCC) were identified between 2015 and 2018 using the National Cancer Database (NCDB). The patients were categorized into different groups according to their histology and initial treatment modalities, which included targeted therapy (TT), immunotherapy (IO), or a combination of both (TT + IO).
The Kruskal-Wallis test was utilized to evaluate variations in baseline characteristics for continuous variables, while the Chi-square or Fisher’s exact test was employed for categorical variables. The study employed Kaplan-Meier estimates and multivariable Cox regression analyses for survival analysis. A cohort of 6,920 individuals who were diagnosed with metastatic renal cell carcinoma (RCC) was examined, wherein 594 (8.6%) were identified as having papillary RCC (pRCC) and 6,326 (91.4%) were identified as having clear cell RCC (ccRCC). A total of 4,710 patients were administered with TT, comprising 455 cases of pRCC and 4,255 cases of ccRCC. Additionally, 1,585 patients were treated with IO, including 77 cases of pRCC and 1,508 cases of ccRCC. Furthermore, 625 patients received a combination of TT and IO, which included 62 cases of pRCC and 563 cases of ccRCC.
During the period from 2015 to 2018, there was a noticeable rise in the usage of IO (immunotherapy) and TT + IO (targeted therapy plus immunotherapy) for treating pRCC (papillary renal cell carcinoma) and ccRCC (clear cell renal cell carcinoma). In individuals diagnosed with metastatic papillary renal cell carcinoma, the use of immune-oncology treatment (IO) did not result in a statistically significant improvement in overall survival (OS) when compared to targeted therapy (TT) alone, as evidenced by a hazard ratio (HR) of 1.03 and a 95% CI of 0.75-1.42. Similarly, the combination of TT and IO, as indicated by an HR of 0.90 and a 95% CI of 0.63-1.28, did not demonstrate a significant association with improved OS when compared to TT alone. The results indicate that patients with metastatic clear cell renal cell carcinoma (ccRCC) who received either immunotherapy (IO) or a combination of targeted therapy (TT) and IO had a significantly improved overall survival (OS) compared to those who received only TT. The IO group’s hazard ratio (HR) was 0.75 with a 95% CI of 0.68-0.82, while the HR for the TT+IO group was 0.82 with a 95% CI of 0.72-0.93. The results indicate that cytoreductive nephrectomy yielded a superior overall survival rate in patients with both pRCC (hazard ratio [HR] 0.59, 95% CI 0.46–0.77) and ccRCC (HR 0.54, 95% CI 0.50–0.58). While patients with metastatic clear cell renal cell carcinoma (ccRCC) demonstrated improved OS with intraoperative (IO) and transarterial tumor treatment (TT) in combination with IO, this correlation was not evident in patients with papillary renal cell carcinoma (pRCC).