Sterile inflammation via TRPM8 RNA-dependent TLR3-NF-kB/IRF3 activation promotes antitumor immunity in prostate cancer.

Inflammation is a common condition of prostate tissue, whose impact on carcinogenesis is highly debated. Microbial colonization is a well-documented cause of a small percentage of prostatitis cases, but it remains unclear what underlies the majority of sterile inflammation reported. Here, androgen- independent fluctuations of PSA expression in prostate cells have lead us to identify a prominent function of the Transient Receptor Potential Cation Channel Subfamily M Member 8 (TRPM8) gene in sterile inflammation. Prostate cells secret TRPM8 RNA into extracellular vesicles (EVs), which primes TLR3/NF-kB-mediated inflammatory signaling after EV endocytosis by epithelial cancer cells. Furthermore, prostate cancer xenografts expressing a translation-defective form of TRPM8 RNA contain less collagen type I in the extracellular matrix, significantly more infiltrating NK cells, and larger necrotic areas as compared to control xenografts. These findings imply sustained, androgen-independent expression of TRPM8 constitutes as a promoter of anticancer innate immunity, which may constitute a clinically relevant condition affecting prostate cancer prognosis.

Global real-world experiences with pembrolizumab in advanced urothelial carcinoma after platinum-based chemotherapy: the ARON-2 study.

BACKGROUND: Immune checkpoint inhibitors have changed previous treatment paradigm of advanced urothelial carcinoma (UC). The ARON-2 study (NCT05290038) aimed to assess the real-world effectiveness of pembrolizumab in patients recurred or progressed after platinum-based chemotherapy. PATIENTS AND METHODS: Medical records of patients with documented metastatic UC treated by pembrolizumab as second-line therapy were retrospectively collected from 88 institutions in 23 countries. Patients were assessed for overall survival (OS), progression-free survival (PFS) and overall response rate (ORR). Cox proportional hazards models were adopted to explore the presence of prognostic factors. RESULTS: In total, 836 patients were included: 544 patients (65%) received pembrolizumab after progression to first-line platinum-based chemotherapy in the metastatic setting (cohort A) and 292 (35%) after recurring within < 12 months since the completion of adjuvant or neoadjuvant chemotherapy (cohort B). The median follow-up time was 15.3 months. The median OS and the ORR were 10.5 months and 31% in the overall study population, 9.1 months and 29% in cohort A and 14.6 months and 37% in cohort B. At multivariate analysis, ECOG-PS ≥ 2, bone metastases, liver metastases and pembrolizumab setting (cohort A vs B) proved to be significantly associated with worst OS and PFS. Stratified by the presence of 0, 1-2 or 3-4 prognostic factors, the median OS was 29.4, 12.5 and 4.1 months (p < 0.001), while the median PFS was 12.2, 6.4 and 2.8 months, respectively (p < 0.001). CONCLUSIONS: Our study confirms that pembrolizumab is effective in the advanced UC real-world context, showing outcome differences between patients recurred or progressed after platinum-based chemotherapy.

Plasma microRNA Signature as Companion Diagnostic for Abiraterone Acetate Treatment in Metastatic Castration-Resistant Prostate Cancer: A Pilot Study.

Abiraterone acetate (AA) serves as a medication for managing persistent testosterone production in patients with metastatic castration-resistant prostate cancer (mCRPC). However, its efficacy varies among individuals; thus, the identification of biomarkers to predict and follow treatment response is required. In this pilot study, we explored the potential of circulating microRNAs (c-miRNAs) to stratify patients based on their responsiveness to AA. We conducted an analysis of plasma samples obtained from a cohort of 33 mCRPC patients before and after three, six, and nine months of AA treatment. Using miRNA RT-qPCR panels for candidate discovery and TaqMan RT-qPCR for validation, we identified promising miRNA signatures. Our investigation indicated that a signature based on miR-103a-3p and miR-378a-5p effectively discriminates between non-responder and responder patients, while also following the drug's efficacy over time. Additionally, through in silico analysis, we identified target genes and transcription factors of the two miRNAs, including PTEN and HOXB13, which are known to play roles in AA resistance in mCRPC. In summary, our study highlights two c-miRNAs as potential companion diagnostics of AA in mCRPC patients, offering novel insights for informed decision-making in the treatment of mCRPC.

Real-world effectiveness of pembrolizumab as first-line therapy for cisplatin-ineligible patients with advanced urothelial carcinoma: the ARON-2 study.

BACKGROUND: The advent of immune-checkpoint inhibitors has challenged previous treatment paradigms for advanced urothelial carcinoma (UC) in the post-platinum setting as well as in the first-line setting for cisplatin-ineligible patients. In this study, we investigated the effectiveness of pembrolizumab as first-line treatment for cisplatin-ineligible UC. METHODS: Data from patients aged ≥ 18 years with cisplatin-ineligible UC and receiving first-line pembrolizumab from January 1st 2017 to September 1st 2022 were collected. Cisplatin ineligibility was defined according to the Galsky criteria. Thirty-three Institutions from 18 countries were involved in the ARON-2 study. RESULTS: Our analysis included 162 patients. The median follow-up time was 18.9 months (95%CI 15.3-76.9). In the overall study population, the median OS was 15.8 months (95%CI 11.3-32.4). The median OS was significantly longer in males versus females while no statistically significant differences were observed between patients aged < 65y versus ≥ 65y and between smokers and non-smokers. According to Recist 1.1 criteria, 26 patients (16%) experienced CR, 32 (20%) PR, 39 (24%) SD and 55 (34%) PD. CONCLUSIONS: Our data confirm the role of pembrolizumab as first-line therapy for cisplatin-unfit patients. Further studies investigating the biological and immunological characteristics of UC patients are warranted in order to optimize the outcome of patients receiving immunotherapy in this setting.

Use of concomitant proton pump inhibitors, statins or metformin in patients treated with pembrolizumab for metastatic urothelial carcinoma: data from the ARON-2 retrospective study.

BACKGROUND: Concomitant medications may potentially affect the outcome of cancer patients. In this sub-analysis of the ARON-2 real-world study (NCT05290038), we aimed to assess the impact of concomitant use of proton pump inhibitors (PPI), statins, or metformin on outcome of patients with metastatic urothelial cancer (mUC) receiving second-line pembrolizumab. METHODS: We collected data from the hospital medical records of patients with mUC treated with pembrolizumab as second-line therapy at 87 institutions from 22 countries. Patients were assessed for overall survival (OS), progression-free survival (PFS), and overall response rate. We carried out a survival analysis by a Cox regression model. RESULTS: A total of 802 patients were eligible for this retrospective study; the median follow-up time was 15.3 months. PPI users compared to non-users showed inferior PFS (4.5 vs. 7.2 months, p = 0.002) and OS (8.7 vs. 14.1 months, p < 0.001). Concomitant PPI use remained a significant predictor of PFS and OS after multivariate Cox analysis. The use of statins or metformin was not associated with response or survival. CONCLUSIONS: Our study results suggest a significant prognostic impact of concomitant PPI use in mUC patients receiving pembrolizumab in the real-world context. The mechanism of this interaction warrants further elucidation.

The impact of proton-pump inhibitors administered with tyrosine kinase inhibitors in patients with metastatic renal cell carcinoma.

Tyrosine kinase inhibitors (TKIs) are the backbone of the systemic treatment for patients with metastatic renal cell carcinoma (mRCC). TKIs such as pazopanib and cabozantinib can interact with other drugs concomitantly administered, particularly with proton-pump inhibitors (PPIs), possibly impacting the effectiveness of the anticancer treatment and patients outcome. Few data are available about this interaction. We conducted a multicenter retrospective observational data collection of patients with mRCC treated with pazopanib or cabozantinib between January 2012 and December 2020 in nine Italian centers. Univariate and multivariate analyses were performed. The aim was to describe the impact of baseline concomitant PPIs on the outcome of patients to pazopanib and cabozantinib in terms of response, progression-free survival (PFS) and overall survival (OS), toxicity, and treatment compliance. The use of PPI in our study population (301 patients) significantly influenced the effectiveness of TKIs with worse PFS (16.3 vs. 9.9 months; P < 0.001) and OS (30.6 vs. 18.4 months; P = 0.013) in patients taking PPI at TKI initiation. This detrimental effect was maintained both in the pazopanib and cabozantinib groups. The use of PPI influenced the toxicity and TKI treatment compliance with a reduction of dose or schedule modifications, and treatment interruptions in the population taking PPIs. Our study demonstrates that the use of PPIs can significantly influence the outcome and compliance of patients with mRCC to TKI treatment, suggesting the importance of a more careful selection of patients who need a gastroprotective therapy, avoiding indiscriminate use of PPIs.

Adherence to Oral Treatments in Older Patients with Advanced Prostate Cancer, the ADHERE Study: A Prospective Trial of the Meet-URO Network.

BACKGROUND: Novel androgen receptor signaling inhibitors for prostate cancer (PC) impose the burden of self-administration on older patients overwhelmed by the requirement of many other concomitant medications. PATIENTS AND METHODS: This study evaluated the proportion of non-adherence in a 12-month follow-up period and the first 3 months to abiraterone (ABI) or enzalutamide (ENZ). In a prospective multicenter observational cohort study, patients with metastatic castration-resistant PC (mCRPC) aged ≥70 years receiving ABI or ENZ pre- or post-docetaxel were enrolled. Treatment monitoring included pill counting, a self-assessment questionnaire, and clinical diaries at each clinical visit. Non-adherence rates were based on proportions of missed/prescribed pills ratios by pill counting. RESULTS: Overall, 234 patients were recruited with median age of 78 years (range, 73-82); 86 (37%) were treated with ABI, and 148 (63%) with ENZ. The median follow-up for adherence was seven monthly cycles (IQR: 4-12). The two cohorts were well balanced for baseline characteristics. The percentage of non-adherence by pill counting was slightly higher for ABI than ENZ (5.2% vs. 4.2%, P < .001). By self-reporting, patients on ENZ tended to report more frequently than those with ABI forgetfulness as the reason for missing events (42% vs. 17%, P < .001). A lower Geriatric G8 score correlated with non-adherence (P = .004). Overall survival (OS) was 48.8 months. Patients on ABI had radiographic progression-free survival (rPFS) of 28.4 [24.2-32.5], while for ENZ patients, we reported a median rPFS of 23.1 [18.2-28.1] months. CONCLUSION: Physicians tend to treat older mCRPC patients with ENZ. Non-adherence rate is relatively low overall but can be higher with ABI than with ENZ and correlates with the Geriatric G8 score. Forgetfulness is a potential barrier for ENZ.

The prognostic value of the previous nephrectomy in pretreated metastatic renal cell carcinoma receiving immunotherapy: a sub-analysis of the Meet-URO 15 study.

BACKGROUND: Nephrectomy is considered the backbone of managing patients with localized and selected metastatic renal cell carcinoma (mRCC). The prognostic role of nephrectomy has been widely investigated with cytokines and targeted therapy, but it is still unclear in the immunotherapy era. METHODS: We investigated the Meet-URO-15 study dataset of 571 pretreated mRCC patients receiving nivolumab as second or further lines about the prognostic role of the previous nephrectomy (received in either the localized or metastatic setting) in the overall population and according to the Meet-URO score groups. RESULTS: Patients who underwent nephrectomy showed a significantly reduced risk of death (HR 0.44, 95% CI 0.32-0.60, p < 0.001) with a longer median overall survival (OS) (35.9 months vs 12.1 months), 1-year OS of 71.6% vs 50.5% and 2-years OS of 56.5% vs 22.0% compared to those who did not. No significant interaction between nephrectomy and the overall five Meet-URO score risk groups was observed (p = 0.17). It was statistically significant when merging group 1 with 2 and 3 and group 4 with 5 (p = 0.038) and associated with a longer OS for the first three prognostic groups (p < 0.001), but not for groups 4 and 5 (p = 0.54). CONCLUSIONS: Our study suggests an overall positive impact of the previous nephrectomy on the outcome of pretreated mRCC patients receiving immunotherapy. The clinical relevance of cytoreductive nephrectomy, optimal timing and patient selection deserves further investigation, especially for patients with Meet-URO scores of 1 to 3, who are the once deriving benefit in our analyses. However, that benefit is not evident for IMDC poor-risk patients (including the Meet-URO score groups 4 and 5) and a subgroup of IMDC intermediate-risk patients defined as group 4 by the Meet-URO score.

A Remote Monitoring System to Optimize the Home Management of Oral Anticancer Therapies (ONCO-TreC): Prospective Training-Validation Trial.

BACKGROUND: A platform designed to support the home management of oral anticancer treatments and provide a secure web-based patient-health care professional communication modality, ONCO-TreC, was tested in 3 cancer centers in Italy. OBJECTIVE: The overall aims of the trial are to customize the platform; assess the system's ability to facilitate the shared management of oral anticancer therapies by patients and health professionals; and evaluate system usability and acceptability by patients, caregivers, and health care professionals. METHODS: Patients aged ≥18 years who were candidates for oral anticancer treatment as monotherapy with an Eastern Cooperative Oncology Group performance status score of 0 to 1 and a sufficient level of familiarity with mobile devices were eligible. ONCO-TreC consisted of a mobile app for patients and a web-based dashboard for health care professionals. Adherence to treatment (pill count) and toxicities reported by patients through the app were compared with those reported by physicians in medical records. Usability and acceptability were evaluated using questionnaires. RESULTS: A total of 40 patients were enrolled, 38 (95%) of whom were evaluable for adherence to treatment. The ability of the system to measure adherence to treatment was high, with a concordance of 97.3% (95% CI 86.1%-99.9%) between the investigator and system pill count. Only 60% (3/5) of grade 3, 54% (13/24) of grade 2, and 19% (7/36) of grade 1 adverse events reported by physicians in the case report forms were also reported in the app directly by patients. In total, 94% (33/35) of patients had ≥1 app launch each week, and the median number of daily accesses per patient was 2. Approximately 71% (27/38) and 68% (26/38) of patients used the app for messages and vital sign entering, respectively, at least once during the study period. CONCLUSIONS: ONCO-TreC is an important tool for measuring and monitoring adherence to oral anticancer drugs. System usability and acceptability were very high, whereas its reliability in registering toxicity could be improved. TRIAL REGISTRATION: ClinicalTrials.gov NCT02921724; https://www.clinicaltrials.gov/ct2/show/NCT02921724.

Management of brain metastases from lung cancer in the era of immunotherapy: a review of the literature.

The brain is one of the most frequent sites of metastases in lung cancer patients, whose prognosis is related to the histological, biomolecular and clinical features of the disease. Over the years, the survival has improved significantly with the introduction of immune checkpoint inhibitors (ICIs), but there are limited data concerning their efficacy in patients with brain metastases. The aim of this review is to describe the biological mechanisms supporting the use of immunotherapy for brain metastases and the outcomes experienced by lung cancer patients with brain involvement enrolled in Phase III registration trials of ICIs. We also review retrospective data on ICIs alone or combined with brain radiotherapy, and indicate future directions for preclinical and clinical research.

Sequencing radium 223 and other life-prolonging agents in castration-resistant prostate cancer patients.

Background: Radium 223 (RA223) is currently administered as part of a therapeutic sequence with the other life-prolonging agents (LPAs) for metastatic castration-resistant prostate cancer (mCRPC). Patients & methods: We retrospectively reviewed the clinical records of patients who had received at least three LPAs including RA223. Results: Median overall survival (OS) from the start of first-line treatment was 39.8 months, with the patients who completed all six planned courses of RA223 having a longer OS than those who did not (53.2 vs 29.5 months; p < 0.0001). Conclusions: Our study confirms the activity of RA223 regardless of the treatment line in which it is administered and suggests that patient selection plays a central role in maximizing this activity.

An Italian, multicenter, real-world, retrospective study of first-line pazopanib in unselected metastatic renal-cell carcinoma patients: the 'Pamerit' study.

OBJECTIVE: Despite the current immunotherapy era, VEGFR inhibitors maintain effectiveness in metastatic renal cell cancer. Real-world data concerning pazopanib are limited. The aim of this study is to add information about efficacy and safety of pazopanib as first-line treatment in metastatic renal cell cancer patients not enrolled into clinical trials. METHODS: Retrospective analysis (the PAMERIT study) of first-line pazopanib in real-world metastatic renal cell cancer patients among 39 Centers in Italy. Outcomes were progression-free survival, overall survival, objective response rate and treatment-related adverse events. Kaplan-Meier curves, log-rank test and multivariable Cox's models were used and adjusted for age, histology, previous renal surgery, International Metastatic RCC Database Consortium score and pazopanib initial dose. RESULTS: Among 474 patients, 87.3% had clear cell metastatic renal cell cancer histology. Most of them (84.6%) had upfront renal surgery. Median progression-free survival and overall survival were 15.8 and 34.4 months, respectively, significantly correlating with International Metastatic RCC Database Consortium's good prognosis (P < 0.001), ECOG PS 0 (P < 0.001), age (<75 years, P = 0.005), surgery (P < 0.001) and response to pazopanib (P < 0.001). After 3 months of pazopanib, overall disease control rate have been observed in 76.6% patients. Among International Metastatic RCC Database Consortium's favorable group patients, 57/121 (47%) showed complete/partial response. No unexpected AEs emerged. CONCLUSIONS: In this real-world study, metastatic renal cell cancer patients treated with first-line pazopanib reached greater progression-free survival and overall survival than in pivotal studies and had high response rates when belonging to International Metastatic RCC Database Consortium's favorable group, without new toxicities. Pazopanib has been confirmed a valid first-line option for International Metastatic RCC Database Consortium's good prognosis metastatic renal cell cancer patients who cannot be submitted to immunotherapy.

Learning from organisational changes in the management of breast cancer patients during the COVID-19 pandemic: Preparing for a second wave at a breast unit in northern Italy.

Italy was the first western country to be hit by the initial wave of severe adult respiratory syndrome coronavirus 2 pandemic, which has been more widespread in the country's northern regions. Early reports showing that cancer patients are more susceptible to the infection posed a particular challenge that has guided our Breast Unit at Hub Hospital in Trento to making a number of stepwise operational changes. New internal guidelines and treatment selection criteria were drawn up by a virtual multidisciplinary tumour board that took into account the risks and benefits of treatment, and distinguished the patients requiring immediate treatment from those whose treatment could be delayed. A second wave of the pandemic is expected in the autumn as gatherings in closed places increase. We will take advantage of the gained experience and organisational changes implemented during the first wave in order to improve further, and continue to offer breast cancer management and treatment to our vulnerable patient population.

Fracture risk and survival outcomes in metastatic castration-resistant prostate cancer patients sequentially treated with abiraterone acetate and RADIUM-223.

PURPOSE: To evaluate the fracture risk and survival outcomes in patients with metastatic castration-resistant prostate cancer (mCRPC) who received sequentially abiraterone acetate (AA) and radium 223 [223Ra]RaCl2 in the daily clinical practice. MATERIALS: We retrospectively reviewed the records of mCRPC patients who received [223Ra]RaCl2 immediately after progressing during an AA treatment line in everyday clinical practice. RESULTS: We reviewed data of a consecutive series of 94 mCRPC patients. Most of the patients (85.1%) received [223Ra]RaCl2 as second- or third-line treatment. [223Ra]RaCl2 treatment was well-tolerated; there were only four cases of grade 3 anaemia, two cases of grade 3 leukopenia and one case of grade 3 neutropenia. The overall fracture rate is 2.1%; one fracture was recorded during the course of [223Ra]RaCl2 treatment, and one was recorded 1 month after its end. The fractures both occurred at metastatic sites. Median OS from [223Ra]RaCl2 start was more than 14 months regardless of the treatment line when [223Ra]RaCl2 was administered. CONCLUSION: The findings of this study show that the treatment with [223Ra]RaCl2 immediately after AA was active and safe with a very low risk of a fracture. Thus, the present observational report makes a valuable contribution to the current debate concerning the risks and benefits of including [223Ra]RaCl2 in the therapeutic algorithm.

Myositis and myasthenia during nivolumab administration for advanced lung cancer: a case report and review of the literature.

The immunotherapy significantly improved survival of non-small cell lung cancer patients, but it may cause immune-related adverse events, which are severe in less than 10% of cases. We report the case of one patient who developed myositis and myasthenia during nivolumab treatment for metastatic lung squamous carcinoma. Moreover, we reviewed literature data in order to identify similar cases in cancer patients treated with immune-checkpoints inhibitors. A 65-year-old patient, who had previously received a first-line platinum-based therapy, developed diplopia and ptosis 4 weeks after the start of nivolumab. Although antibodies associated with myositis, myasthenia gravis and paraneoplastic syndromes were absent, immune-related myositis and myasthenia were diagnosed. Corticosteroids, immunoglobulin and pyridostigmine showed poor efficacy and the patient died 7 weeks after the appearance of the first symptoms. Fifteen similar cases were found in the literature. A close collaboration between different specialists is essential to rapidly identify and treat severe immune-related adverse events.

Sequencing strategies in the new treatment landscape of prostate cancer.

Over the last 10 years, a number of new agents approved for the treatment of metastatic castration-resistant prostate cancer have led to a significant improvement in overall survival. The addition of new agents to androgen deprivation therapy has also allowed a paradigmatic change in the treatment of metastatic hormone-sensitive prostate cancer by improving overall survival in comparison with androgen deprivation therapy alone. Furthermore, recent data concerning the efficacy of three different androgen receptor-targeting agents in patients with nonmetastatic castration-resistant prostate cancer have opened up new scenarios for future patients' management. Defining the best sequencing strategies for men with prostate cancer is a currently unmet medical need, and choosing treatment is often challenging for clinicians because of the lack of direct comparisons of the available agents. The aim of this paper is to provide a comprehensive review of the literature concerning current sequencing strategies for prostate cancer patients.

Activity and safety of metronomic cyclophosphamide in the modern era of metastatic castration-resistant prostate cancer.

AIM: To evaluate activity of metronomic cyclophosphamide (mCTX) in heavily pretreated metastatic castration-resistant prostate cancer (mCRPC) patients. PATIENTS & METHODS: We retrospectively evaluated a consecutive series of 74 mCRPC patients treated with at least one new agent after docetaxel failure, who received once-daily oral mCTX treatment at a fixed dose of 50 mg. RESULTS: The treatment was well tolerated. Sixteen percent of the patients experienced a major biochemical response. Median progression-free survival was 4.0 months, and median overall survival was 8.1 months. CONCLUSIONS: In the modern context of mCRPC, mCTX may represent a valuable and inexpensive alternative to new agents, which have shown similar activity in heavily pretreated patients.

Abiraterone acetate and its use in the treatment of metastatic prostate cancer: a review.

Abiraterone acetate, which targets enzymatic complexes playing a central role in steroidogenesis, demonstrated to increase survival significantly in both chemo-naive and docetaxel pretreated, becoming one of the drugs of choice for metastatic castration-resistant prostate cancer. More recently, this agent in combination to androgen deprivation therapy demonstrated to be efficacious also in metastatic castration-sensitive prostate cancer. The present review is aimed to outline the clinical development of abiraterone acetate, the pivotal trials which led to its approval for the clinical practice, new evidence about its efficacy in metastatic castration-sensitive prostate cancer, its place in the therapeutic landscape of prostate cancer and future directions of development.

Enzalutamide after chemotherapy in advanced castration-resistant prostate cancer: the Italian Named Patient Program.

AIM: To collect efficacy and safety data of enzalutamide after docetaxel, we retrospectively evaluated the Italian Named Patient Program results. PATIENTS & METHODS: Two hundred and nine metastatic castration-resistant prostate cancer patients were enrolled. Median age was 73 years. Total 42.1% patients had pain, 14.4% had a performance status of two and 59.8% had a Gleason score ≥8. Total 31.1% had previously received ≥2 chemotherapies, 15.3 and 12% had been previously treated with abiraterone and cabazitaxel, respectively and 14.8% had received both. RESULTS:  Median progression-free survival and overall survival were 4.8 and 13.1 months, respectively. A prostate-specific antigen reduction ≥50% was observed in 49.1%. Total 32.7% abiraterone-pretreated patients achieved a biochemical response compared with 56% of abiraterone-naive patients. CONCLUSION:  Enzalutamide was safe and well tolerated. Its antitumor activity in abiraterone-pretreated patients was limited.

Long-term clinical impact of PSA surge in castration-resistant prostate cancer patients treated with abiraterone.

BACKGROUND: Early changes in PSA have been evaluated in association to treatment outcome. The aim of this study was to assess PSA surge phenomenon in castration-resistant prostate cancer (CRPC) patients treated with abiraterone and to correlate those variations with long-term treatment outcome. PATIENTS AND METHODS: We retrospectively evaluated 330 CRPC patients in 11 Italian hospitals, monitoring PSA levels at baseline and every 4 weeks. Other clinical, biochemical and molecular parameters were determined at baseline. We considered PSA surge as PSA increase within the first 8 weeks from starting abiraterone more than 1% from baseline followed by a PSA decline. The log-rank test was applied to compare survival between groups of patients according to PSA surge. The impact of PSA surge on survival was evaluated by Cox regression analyses. RESULTS: A total of 330 patients with CRPC, median age 74 years (range, 45-90), received abiraterone (281 chemotherapy-treated and 49 chemotherapy-naïve). PSA surge was observed in 20 (7%) post-chemotherapy and 2 (4%) chemotherapy-naïve patients. For overall patients presenting PSA surge, timing of PSA peak from baseline was 5 ± 1.8 weeks and PSA rise from baseline was 21 ± 18.4%. The overall median follow-up was 23 months (range 1-62). No significant differences in progression-free survival and overall survival were observed between patients with and without PSA surge (P = 0.16 and =0.86, respectively). In addition, uni- and multivariate analyses showed no baseline factors related to PSA surge. CONCLUSION: PSA surge occurs in both chemotherapy-treated and chemotherapy-naïve patients treated with abiraterone resulting, however, in no long-term impact on outcome. Physicians and patients should be aware of PSA surge challenge to prevent a premature discontinuation of potentially effective therapy with abiraterone. Further larger and prospective studies are warranted to investigate this not infrequent phenomenon.