Praful Ravi

BACKGROUND: Loss of the tumor suppressor phosphatase and tensin homolog (PTEN) occurs frequently in prostate cancers. Preclinical evidence suggests that activation of PI3K/AKT signaling through loss of PTEN can result in resistance to hormonal treatment in prostate cancer. OBJECTIVE: To explore the antitumor activity of abiraterone acetate (abiraterone) in castration-resistant prostate cancer (CRPC) patients with and without loss of PTEN protein expression. DESIGN, SETTING, AND PARTICIPANTS: We retrospectively identified patients who had received abiraterone and had hormone-sensitive prostate cancer (HSPC) and/or CRPC tissue available for PTEN immunohistochemical analysis. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary end point was overall survival from initiation of abiraterone treatment. Relationship with outcome was analyzed using multivariate Cox regression and log-rank analyses. RESULTS AND LIMITATIONS: A total of 144 patients were identified who had received abiraterone post-docetaxel and had available tumor tissue. Overall, loss of PTEN expression was observed in 40% of patients. Matched HSPC and CRPC tumor biopsies were available for 41 patients. PTEN status in CRPC correlated with HSPC in 86% of cases. Loss of PTEN expression was associated with shorter median overall survival (14 vs 21 mo; hazard ratio [HR]: 1.75; 95% confidence interval [CI], 1.19-2.55; p=0.004) and shorter median duration of abiraterone treatment (24 vs 28 wk; HR: 1.6; 95% CI, 1.12-2.28; p=0.009). PTEN protein loss, high lactate dehydrogenase, and the presence of visceral metastases were identified as independent prognostic factors in multivariate analysis. CONCLUSIONS: Our results indicate that loss of PTEN expression was associated with worse survival and shorter time on abiraterone treatment. Further studies in larger and prospective cohorts are warranted. PATIENT SUMMARY: PTEN is a protein often lost in prostate cancer cells. In this study we evaluated if prostate cancers that lack this protein respond differently to treatment with abiraterone acetate. We demonstrated that the survival of patients with loss of PTEN is shorter than patients with normal PTEN expression.

Advances in therapy in recent years have led investigators to challenge the dogma that multiple myeloma (MM) is incurable. We assessed overall (OS) and progression-free survival (PFS) of young patients ( ≤ 50 years) with MM and compared outcomes with follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL), and Hodgkin lymphoma (HL). All patients ≤ 50 years with newly diagnosed MM (n = 212), FL (n = 168), DLBCL (n = 195), and HL (n = 233) between 1 January 2005 and 31 December 2015 were included. Observed vs. expected survival was summarized by standardized mortality ratios (SMR). Compared to the background US population, excess mortality risk was seen at diagnosis in all four cancers, SMR 19.5 (15.2-24.5) in MM, 4.2 (2.3-7.2) in FL, 13.0 (9.2-18.4) in DLBCL, and 5.2 (2.6-9.3) in HL. We reasoned that cure would most likely occur in the first 3 years after diagnosis and be reflected by an overall survival probability similar to the background population. From the 36-month landmark, excess mortality risk was seen in MM (SMR 20.7 [14.7-28.3]) and FL (SMR 3.8 [1.5-7.8]), but not with DLBCL (SMR 3.1 [0.8-8.0]) or HL (SMR 0.9 [0.0-5.1]). MM patients have 20-fold excess mortality risk compared to the background population at diagnosis and at 3 years after diagnosis, suggesting that MM remains an incurable cancer.

Importance: Several immune checkpoint inhibitors (ICIs) are approved for use in patients with metastatic renal cell carcinoma (mRCC), but the efficacy and safety of ICI rechallenge in mRCC is unknown. Objective: To evaluate the safety and efficacy of ICI rechallenge in patients with mRCC. Design, Setting, and Participants: This multicenter, retrospective cohort study included consecutive patients with mRCC from 9 institutions in the US who received at least 2 separate lines of ICI (ICI-1, ICI-2) between January 2012 and December 2019. Exposure: Receipt of an ICI (anticytotoxic T-lymphocyte-associated protein 4, anti-programmed cell death protein 1, or anti-programmed cell death ligand 1), alone or in combination with other therapies, in at least 2 separate lines of therapy for mRCC. Main Outcomes and Measures: Investigator-assessed best overall response and immune-related adverse events. Results: A total of 69 patients were included. Median (range) age at diagnosis of mRCC was 61 (36-86) years. Of these, 50 were men and 19 were women. The most common therapies received at ICI-1 were single-agent ICI (n = 27 [39%]) or ICI in combination with targeted therapy (n = 29 [42%]), while at ICI-2, the most common therapies were single-agent ICI (n = 26 [38%]) or dual ICI (n = 22 [32%]). Most patients discontinued ICI-1 owing to disease progression (n = 50 [72%]) or toxic effects (n = 16 [23%]). The overall response rates at ICI-1 and ICI-2 were 37% and 23%, respectively. The likelihood of a response at ICI-2 was greatest among patients who had previously responded to ICI-1 (7 of 24 [29%]), although responses at ICI-2 were seen in those who had progressive disease as their best response following ICI-1 (3 of 14 [21%]) as well as in those who received single-agent ICI at ICI-2 (7 of 23 [30%]). Grade 3 or higher immune-related adverse events were seen in 18 patients (26%) and 11 patients (16%) at ICI-1 and ICI-2, respectively. There were no treatment-related deaths. Conclusions and Relevance: The findings of this multicenter cohort study suggest that ICI rechallenge in patients with mRCC may be safe and reasonably efficacious, with an overall response rate of 23%. Data from prospective studies are needed to validate these findings and determine the role of sequential ICI regimens in treatment of mRCC.

Importance: The effectiveness of triplet therapy compared with androgen pathway inhibitor (API) doublets in a heterogeneous patient population with metastatic castration-sensitive prostate cancer (mCSPC) is unknown. Objective: To assess the comparative effectiveness of contemporary systemic treatment options for patients with mCSPC across clinically relevant subgroups. Data Sources: For this systematic review and meta-analysis, Ovid MEDLINE and Embase were searched from each database's inception (MEDLINE, 1946; Embase, 1974) through June 16, 2021. Subsequently, a "living" auto search was created with weekly updates to identify new evidence as it became available. Study Selection: Phase 3 randomized clinical trials (RCTs) assessing first-line treatment options for mCSPC. Data Extraction and Synthesis: Two independent reviewers extracted data from eligible RCTs. The comparative effectiveness of different treatment options was assessed with a fixed-effect network meta-analysis. Data were analyzed on July 10, 2022. Main Outcomes and Measures: Outcomes of interest included overall survival (OS), progression-free survival (PFS), grade 3 or higher adverse events, and health-related quality of life. Results: This report included 10 RCTs with 11 043 patients and 9 unique treatment groups. Median ages of the included population ranged from 63 to 70 years. Current evidence for the overall population suggests that the darolutamide (DARO) triplet (DARO + docetaxel [D] + androgen deprivation therapy [ADT]; hazard ratio [HR], 0.68; 95% CI, 0.57-0.81), as well as the abiraterone (AAP) triplet (AAP + D + ADT; HR, 0.75; 95% CI, 0.59-0.95), are associated with improved OS compared with D doublet (D + ADT) but not compared with API doublets. Among patients with high-volume disease, AAP + D + ADT may improve OS compared with D + ADT (HR, 0.72; 95% CI, 0.55-0.95) but not compared with AAP + ADT, enzalutamide (E) + ADT, and apalutamide (APA) + ADT. For patients with low-volume disease, AAP + D + ADT may not improve OS compared with APA + ADT, AAP + ADT, E + ADT, and D + ADT. Conclusions and Relevance: The potential benefit observed with triplet therapy must be interpreted with careful accounting for the volume of disease and the choice of doublet comparisons used in the clinical trials. These findings suggest an equipoise to how triplet regimens compare with API doublet combinations and provide direction for future clinical trials.