Androgen receptor gene status in plasma DNA associates with worse outcome on enzalutamide or abiraterone for castration-resistant prostate cancer: a multi-institution correlative biomarker study.

BACKGROUND: There is an urgent need to identify biomarkers to guide personalized therapy in castration-resistant prostate cancer (CRPC). We aimed to clinically qualify androgen receptor (AR) gene status measurement in plasma DNA using multiplex droplet digital PCR (ddPCR) in pre- and post-chemotherapy CRPC. METHODS: We optimized ddPCR assays for AR copy number and mutations and retrospectively analyzed plasma DNA from patients recruited to one of the three biomarker protocols with prospectively collected clinical data. We evaluated associations between plasma AR and overall survival (OS) and progression-free survival (PFS) in 73 chemotherapy-naïve and 98 post-docetaxel CRPC patients treated with enzalutamide or abiraterone (Primary cohort) and 94 chemotherapy-naïve patients treated with enzalutamide (Secondary cohort; PREMIERE trial). RESULTS: In the primary cohort, AR gain was observed in 10 (14%) chemotherapy-naïve and 33 (34%) post-docetaxel patients and associated with worse OS [hazard ratio (HR), 3.98; 95% CI 1.74-9.10; P < 0.001 and HR 3.81; 95% CI 2.28-6.37; P < 0.001, respectively], PFS (HR 2.18; 95% CI 1.08-4.39; P = 0.03, and HR 1.95; 95% CI 1.23-3.11; P = 0.01, respectively) and rate of PSA decline ≥50% [odds ratio (OR), 4.7; 95% CI 1.17-19.17; P = 0.035 and OR, 5.0; 95% CI 1.70-14.91; P = 0.003, respectively]. AR mutations [2105T>A (p.L702H) and 2632A>G (p.T878A)] were observed in eight (11%) post-docetaxel but no chemotherapy-naïve abiraterone-treated patients and were also associated with worse OS (HR 3.26; 95% CI 1.47-not reached; P = 0.004). There was no interaction between AR and docetaxel status (P = 0.83 for OS, P = 0.99 for PFS). In the PREMIERE trial, 11 patients (12%) with AR gain had worse PSA-PFS (sPFS) (HR 4.33; 95% CI 1.94-9.68; P < 0.001), radiographic-PFS (rPFS) (HR 8.06; 95% CI 3.26-19.93; P < 0.001) and OS (HR 11.08; 95% CI 2.16-56.95; P = 0.004). Plasma AR was an independent predictor of outcome on multivariable analyses in both cohorts. CONCLUSION: Plasma AR status assessment using ddPCR identifies CRPC with worse outcome to enzalutamide or abiraterone. Prospective evaluation of treatment decisions based on plasma AR is now required. CLINICAL TRIAL NUMBER: NCT02288936 (PREMIERE trial).

A randomized phase II/III study of cabazitaxel versus vinflunine in metastatic or locally advanced transitional cell carcinoma of the urothelium (SECAVIN).

BACKGROUND: Despite the advent of immunotherapy in urothelial cancer, there is still a need to find effective cytotoxic agents beyond first and second lines. Vinflunine is the only treatment approved in this setting by the European Medicines Agency and taxanes are also widely used in second line. Cabazitaxel is a taxane with activity in docetaxel-refractory cancers. A randomized study was conducted to compare its efficacy versus vinflunine. PATIENTS AND METHODS: This is a multicenter, randomized, open-label, phase II/III study, following a Simon's optimal method with stopping rules based on an interim futility analysis and a formal efficacy analysis at the end of the phase II. ECOG Performance Status, anaemia and liver metastases were stratification factors. Primary objectives were overall response rate for the phase II and overall survival for the phase III. RESULTS: Seventy patients were included in the phase II across 19 institutions in Europe. Baseline characteristics were well balanced between the two arms. Three patients (13%) obtained a partial response on cabazitaxel (95% CI 2.7-32.4) and six patients (30%) in the vinflunine arm (95% CI 11.9-54.3). Median progression-free survival for cabazitaxel was 1.9 versus 2.9 months for vinflunine (P = 0.039). The study did not proceed to phase III since the futility analysis showed a lack of efficacy of cabazitaxel. A trend for overall survival benefit was found favouring vinflunine (median 7.6 versus 5.5 months). Grade 3- to 4-related adverse events were seen in 41% patients with no difference between the two arms. CONCLUSION: This phase II/III second line bladder study comparing cabazitaxel with vinflunine was closed when the phase II showed a lack of efficacy of the cabazitaxel arm. Vinflunine results were consistent with those known previously. TRIAL NUMBER: NCT01830231.

Rethinking prognostic factors in locally advanced or metastatic urothelial carcinoma in the immune checkpoint blockade era: a multicenter retrospective study.

BACKGROUND: Few studies have investigated the safety and efficacy of anti-PD-(L)1 antibodies in metastatic urothelial carcinoma (mUC) in daily clinical practice. Knowledge about the influence of baseline clinical and analytical factors on therapy outcomes is scarce. PATIENTS AND METHODS: We conducted a multicenter retrospective study involving 119 previously treated or untreated mUC patients under anti-PD-(L)1 therapy in a real-world scenario. The objectives of this study were to confirm the safety and efficacy of anti-PD-(L)1 monotherapy and to identify pretreatment factors influencing therapy outcomes. In addition, an independent prognostic model for overall survival (OS) was developed and internally validated. RESULTS: Median OS was 7.8 months [95% confidence interval (CI), 5.4-10.4], median progression-free survival (PFS) was 2.80 months (95% CI, 2.4-3.4), disease control rate (DCR) was 40% (95% CI, 31-49), and overall response rate (ORR) was 24% (95% CI, 15-31). Presence of peritoneal metastases was associated with poor OS [hazard ratio (HR) = 2.40, 95% CI, 1.08-5.33; P = 0.03]. Use of proton-pump inhibitors (PPI) was associated with poor OS (HR = 1.83, 95% CI, 1.11-3.02; P = 0.02) and PFS (HR = 1.94, 95% CI, 1.22-3.09; P = 0.005), and lower DCR (OR = 0.38, 95% CI, 0.17-0.89; P = 0.03) and ORR (OR = 0.18, 95% CI, 0.02-1.60; P = 0.002). The three risk category prognostic model developed included Eastern Cooperative Oncology Group performance status, PPI use, albumin level, presence of liver metastases, and presence of peritoneal metastases variables and was associated with higher risk of death (HR = 3.00, 95% CI, 1.97-4.56; P = 0.0001). CONCLUSIONS: This study confirms anti-PD-(L)1 monotherapy as a safe and effective treatment option in daily clinical practice for mUC patients. It also describes the presence of peritoneal metastases as an independent prognostic factor for OS and underlines the association between PPI use and worse therapeutic outcomes. Finally, it proposes a new easy-to-use risk-assessment model for OS prediction.

Latest progress in molecular biology and treatment in genitourinary tumours.

The management of genitourinary cancer, including bladder, prostate, renal and testicular cancer, has evolved dramatically in recent years due to a better understanding of tumour genetic mutations, alterations in molecular pathways, and to the development of new kinds of drugs such as targeted therapies and immunotherapies. In the field of immunotherapy, new drugs focused on stimulating, enhancing and modulating the immune system to detect and destroy cancer, have been recently discovered. Research in oncology moves quickly and new data of great relevance for clinical practice are communicated every year. For this reason, a group of experts, focused exclusively on the treatment of genitourinary tumours and who get together every year in the BestGU conference to assess the latest progress in this field have summarized the most important advances in a single review, along with a critical assessment of whether these results should alter daily clinical practice.

Chemotherapy management for unfit patients with metastatic castration-resistant prostate cancer.

Administration of chemotherapy in prostate cancer depends on patient fitness. In unfit patients, physiological impairment determines the optimum treatment. Although no consensus on assessing patient fitness currently exists, this article proposes an algorithm combining the available information for administering chemotherapy, and in particular docetaxel, in unfit patients. It was constructed by reviewing factors that can influence treatment, such as performance status, taxane-related comorbidities and nutritional status. Geriatric scales for prostate cancer patients and alternative treatment regimens for this population are also reviewed. In summary, patients require overall assessment to optimise treatment. Use of docetaxel should be restricted in unfit patients, and other options must be evaluated, because of high toxicity and low efficacy.

Choroid plexus carcinoma: a rare condition and its therapeutic management.

Choroid plexus carcinomas are rare tumours, found chiefly during childhood. The commonest pattern of progression is via the neural axis. We present the case of a patient with unusual metastatic dissemination, affecting lungs and bones two years after diagnosis, and the approach adopted towards him.

Comprehensive overview of the efficacy and safety of sorafenib in advanced or metastatic renal cell carcinoma after a first tyrosine kinase inhibitor.

We performed a literature search that shed light on the signaling pathways involved in the sorafenib activity as first- or subsequent-line treatment, taking into account its toxicity profile. Sorafenib appears to have better tolerability when compared with other agents in the same indication. Cross-resistance between tyrosine kinase inhibitors (TKIs) may be limited, even after failure with a previous VEGFR inhibitor, but the optimal sequence with TKIs remains to be determined. Randomized trials of second-line treatment options have showed either modest or no differences in terms of progression-free and overall survival (OS). Direct comparison between sorafenib and axitinib demonstrated differences in terms of PFS in favor of axitinib, but not in terms of OS as second-line treatment. In contrast, a phase III study showed a benefit in OS, favoring sorafenib when compared with temsirolimus. In conclusion, after using other VEGF inhibitor such as sunitinib, sorafenib is active and safe for the treatment of patients with advanced or metastatic RCC.