BackgroundNon-clear cell renal cell carcinoma (ccRCC) includes histologically and molecularly distinct subtypes such as papillary, chromophobe, collecting duct, and sarcomatoid RCC, with an incidence ranging from 20% to 25%. Oncologic outcomes and the role of adjuvant systemic therapy [vascular endothelial growth factor inhibitor (VEGFi) or immunotherapy] for non-ccRCC are not well-described.ObjectiveTo assess the incidence and survival outcomes of non-ccRCC subtypes in comparison to ccRCC.MethodsThe National Cancer Database was utilized to identify patients with non-metastatic RCC (T1–T4, N0–N1) between 2004 and 2015. The non-ccRCC cohort was further stratified by histologic subtype: papillary, chromophobe, sarcomatoid, and collecting duct RCC. Multivariable Cox regression models were used to compare overall survival (OS).ResultsThe 5-year OS for chromophobe, papillary, clear cell, collecting duct, and sarcomatoid RCC was 91%, 82%, 81%, 44%, and 40%, respectively. After adjusting for clinicopathologic and treatment characteristics, there was no significant difference in OS between papillary RCC and ccRCC (p = 0.17). Patients with collecting duct and sarcomatoid subtypes were at over two times increased risk of death compared to patients with clear cell (p < 0.01 and p < 0.01, respectively). Conversely, patients with chromophobe RCC were at 36% decreased risk of death compared to ccRCC (p < 0.01).ConclusionsThis hospital-based analysis confirms that collecting duct and sarcomatoid histologic subtypes are uncommon and associated with poor survival after surgery when compared to the other RCC subtypes. Further studies are needed to evaluate the role of neoadjuvant and adjuvant systemic therapies in these subtypes to improve oncologic outcomes.
BackgroundAlthough T4b is known to have worse oncologic outcomes, it is unclear whether it truly shows a worse prognosis. This study aims to compare the survival differences between T4a and T4b.MethodsPatients who were pathologically diagnosed with T3 and T4 colorectal adenocarcinoma from 2010 to 2014 were included (T3, n = 1822; T4a, n = 424; T4b, n = 67). Overall survival (OS) and cancer-specific survival (CSS) were compared between T4a and T4b using the Kaplan-Meier method and log-rank test.ResultsIn stage II, T4a had better OS and CSS than T4b (5-year OS, 89.5% vs. 72.6%; 5-year CSS, 94.4% vs. 81.7%, all p < 0.05), however, in stage III, there were no significant differences in survivals between groups (all p > 0.05). In multivariable analysis, T classification was not an independent risk factor for OS (p > 0.05). However, for CSS, when respectively compared to T3, T4b (HR 3.53, p < 0.001) showed a relatively higher hazard ratio than T4a (HR 2.27, p < 0.001).ConclusionsT4a showed more favorable OS and CSS than T4b, especially in stage II. Our findings support the current AJCC guidelines, in which T4b is presented as a more advanced stage than T4a.