Assessment of PI3K/mTOR/AKT Pathway Elements to Serve as Biomarkers and Therapeutic Targets in Penile Cancer.

The PI3K/mTOR/AKT pathway might represent an intriguing option for treatment of penile cancer (PeCa). We aimed to assess whether members of this pathway might serve as biomarkers and targets for systemic therapy. Tissue of primary cancer from treatment-naïve PeCa patients was used for tissue microarray analysis. Immunohistochemical staining was performed with antibodies against AKT, pAKT, mTOR, pmTOR, pS6, pPRAS, p4EBP1, S6K1 and pp70S6K. Protein expression was correlated with clinicopathological characteristics as well as overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS) and metastasis-free survival (MFS). AKT inhibition was tested in two primarily established, treatment-naïve PeCa cell lines by treatment with capivasertib and analysis of cell viability and chemotaxis. A total of 76 patients surgically treated for invasive PeCa were included. Higher expression of AKT was significantly more prevalent in high-grade tumors and predictive of DSS and OS in the Kaplan-Meier analysis, and an independent predictor of worse OS and DSS in the multivariate regression analysis. Treatment with pan-AKT inhibitor capivasertib in PeCa cell lines induced a significant downregulation of both total AKT and pAKT as well as decreased cell viability and chemotaxis. Selected protein candidates of the mTOR/AKT signaling pathway demonstrate association with histological and survival parameters of PeCa patients, whereas AKT appears to be the most promising one.

The Cancer of the Bladder Risk Assessment (COBRA) score for estimating cancer-specific survival after radical cystectomy: external validation in a large bi-institutional cohort.

OBJECTIVE: To perform an external validation of the Cancer of the Bladder Risk Assessment (COBRA) score for estimating cancer-specific survival (CSS) after radical cystectomy (RC) in a large bi-institutional cohort of patients. PATIENTS AND METHODS: Patients treated with RC and lymph node dissection (LND) between May 1996 and July 2017 were retrieved from the RC databases of Leuven and Turin. Collected variables were age at RC, tumour stage, lymph node (LN) density, neoadjuvant chemotherapy, the extent of LND, and nodal stage. The primary outcome was CSS visualised using Kaplan-Meier plots. Cox proportional hazard models were used to assess the impact of variables on CSS. We performed a pairwise comparison between the COBRA score levels using a log-rank test corrected by Bonferroni, and developed a simplified COBRA score with three risk categories. To compare models, we assessed concordance indices (C-indices), receiver operating characteristic curves with area under the curve (AUC), calibration plots, and decision curve analysis (DCA). Finally, we compared both COBRA and simplified COBRA models with the established American Joint Committee on Cancer (AJCC) model. RESULTS: A total of 812 patients were included. All COBRA score variables had a significant impact on CSS in a Cox proportional hazard model. However, pairwise comparison of the COBRA subscores could not differentiate significantly between all COBRA score levels. Based on these findings, we developed a simplified COBRA score by introducing three categories within the following COBRA score ranges: low- (0-1) vs intermediate- (2-4) vs high-risk (5-7). A pairwise comparison could discriminate significantly between all COBRA risk categories. When finally comparing COBRA and simplified COBRA models with the AJCC model, AJCC performed better than both. C-indices, AUCs, calibration plots and DCA for AJCC were all better compared with the original and simplified COBRA models. CONCLUSION: We performed an external validation of the COBRA score in a large bi-institutional cohort. We observed that several risk groups had overlapping CSS, demonstrating suboptimal performance of the COBRA score. Therefore, we constructed a simplified model with three COBRA score risk categories. This model resulted in demarcated risk groups with non-overlapping CSS and good predictive accuracy. However, both COBRA score models were outperformed by the AJCC staging system. Therefore, we conclude that the AJCC staging system should remain the current standard for stratifying patients after RC for CSS.

Bone metastases and age are associated with earlier dose reductions in metastatic clear-cell renal cell carcinoma patients treated with angiogenesis inhibitors.

Background: Metastatic clear-cell renal cell carcinoma (m-ccRCC) patients with bone metastases (BM) treated with vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKI) have a poorer outcome compared to patients without BM. We aimed to investigate whether an increased incidence of VEGFR-TKI treatment interruptions and/or dose reductions in patients with BM could explain this difference in outcome. Patients and methods: Retrospective study on m-ccRCC patients treated in first-line with VEGFR-TKI. Analysis of the incidence of treatment interruptions and dose reductions and time-to-event analysis. Study of the correlation with the presence of BM at start of first-line VEGFR-TKIs. Results: Two-hundred-and-five patients were included. In patients with BM, median time-to-dose-reduction was significantly shorter (3 versus 5 cycles; p = 0.005) than in patients without BM. 63% of the total number of cycles was administered at reduced dose, compared to 41% in patients without BM. Age at start of VEGFR-TKI (≤ versus >70 years) was significantly associated with median time-to-dose-reduction (5 versus 3 cycles; p = 0.007). On multivariate analysis, the presence of BM (p = 0.004; HR 1.82, 95%CI 1.21-2.73) and age at start of VEGFR-TKIs (p = 0.017; HR 1.65, 95%CI 1.10-2.50) were independently associated with time-to-dose-reduction. Conclusion: In m-ccRCC patients treated with VEGFR-TKIs, dose reductions occurred earlier in patients with BM compared to patients without BM and in elderly patients.