Neoadjuvant cabozantinib restores CD8 T cells in patients with locally advanced non-metastatic clear cell renal cell carcinoma: a phase 2 trial.

Cabozantinib is an oral multikinase inhibitor approved for treatment in metastatic renal cell carcinoma (RCC). We hypothesized that neoadjuvant cabozantinib could downstage localized tumors, facilitating partial nephrectomy, and facilitating surgery in patients with locally advanced tumors that would require significant adjacent organ resection. We, therefore, conducted a phase 2, single-arm trial of cabozantinib treatment for 12 weeks in 17 patients with locally advanced biopsy-proven non-metastatic clear cell RCC before surgical resection. Six patients (35%) experienced a partial response, and 11 patients (65%) had stable disease. We identified that plasma cell-free DNA (cfDNA), VEGF, c-MET, Gas6, and AXL were significantly increased while VEGFR2 decreased during cabozantinib treatments. There was a trend towards CD8+ T cells becoming activated in the blood, expressing the proliferation marker Ki67 and activation markers HLA-DR and CD38. Cabozantinib treatment depleted myeloid populations acutely. Importantly, immune niches made up of the stem-like CD8+ T cells and antigen presenting cells were increased in every patient. These data suggest that cabozantinib treatment was clinically active and safe in the neoadjuvant setting in patients with locally advanced non-metastatic clear cell RCC and activated the anti-tumor CD8+ T cell response. The trial is registered at ClinicalTrials.gov under registration no. NCT04022343.

Predictive factors for recurrence and outcomes in T1a renal cell carcinoma: Analysis of the INMARC (International Marker Consortium for Renal Cancer) database.

OBJECTIVE: Stage migration in renal cell carcinoma (RCC) has led to an increasing proportion of diagnosed small renal masses. Emerging knowledge regarding heterogeneity of RCC histologies and consequent impact on prognosis led us to further explore outcomes and predictive factors in surgically-treated T1a RCC. METHODS: The INMARC database was queried for T1aN0M0 RCC. Patients were stratified into groups based on recurrence. Primary outcome was overall survival (OS). Multivariable analyses (MVA) were performed for factors associated with recurrence, cancer-specific (CSM), and all-cause mortality (ACM). Kaplan-Meier analyses (KMA) assessed survival by histology and grade. Subset analysis for time to recurrence was conducted for grade and histologic groups and compared with recent AUA follow-up guidelines [low-risk (AUA-LR), intermediate-risk (AUA-IR), high-risk (AUA-HR), and very-high risk (AUA-VHR) groups]. RESULTS: We analyzed 1,878 patients (median follow-up 35.2 months); 101 (5.4%) developed recurrence. MVA for recurrence demonstrated increasing age (P = 0.026), male sex (P = 0.043), diabetes (P = 0.007), high/unclassified grade (P < 0.001-0.007), and variant histology (P = 0.017) as independent risk factors for increased risk, while papillary (P = 0.016) and chromophobe (P = 0.049) were associated with decreased risk. MVA identified high/unclassified grade (P = 0.003-0.004) and pT3a upstaging (P = 0.043) as predictive factors for worsened risk of CSM while papillary (P = 0.034) was associated with improved risk. MVA for ACM demonstrated increasing age (P < 0.001), non-white (P < 0.001), high-grade (P = 0.022), variant histology (P = 0.049), recurrence (P = 0.004), and eGFR<45 at last follow-up (P < 0.001) to be independent risk factors. KMA comparing clear cell, chromophobe, papillary, and variant RCC revealed significant differences for 5-year CSS (P = 0.018) and RFS (P < 0.001), but not OS (P = 0.34). Median time to recurrence was 23.8 months for low-grade (AUA-LR), 17.3 months for high-grade (AUA-IR), 18 months for pT3a upstaging (AUA-HR), and 12 months for variant histology (AUA-VHR; P < 0.001). CONCLUSION: We noted differential outcomes in T1a RCC based on histology and grade for recurrence and CSM, while renal functional decline in addition to pathological factors and recurrence were predictive for ACM. Our findings support recently promulgated AUA follow-up guidelines for low-grade and variant histology pT1a RCC, but call for consolidation of follow-up protocols for high-grade pT1a and pT3a upstaged patients, with intensification of frequency of imaging follow-up in pT1a high-grade RCC.