Median Metastasis-free Survival Research Articles

Analyzing Neoadjuvant Chemotherapy Effects in HER2-Low Breast Cancer: Real World Data.

Neoadjuvant chemotherapy (NAC) can be used as upfront therapy in aggressive breast cancer (BC). human epidermal growth factor receptor 2 (HER2)-low BC, defined as tumors scoring +1 or +2 on immunohistochemistry without HER2 gene amplification by in situ hybridization, lacks information on real-world data (RWD) outcomes, especially in the NAC setting. This subgroup, which does not reach the HER2 positive criteria due to its lower receptor expression, represents a distinct clinical category potentially requiring tailored therapeutic approaches. The objective of this study is to characterize patients with BC with HER2-low status who received NAC in a Brazilian public reference center for female tumors and key outcomes such as pathological complete response (pCR), overall survival (OS), and metastasis-free survival (MFS). A retrospective cohort study based on a large BC database from a reference cancer center in Brazil. Patients with BC that received NAC, diagnosed between 2011 and 2020, were included if they presented HER2-low status (defined as tumors scoring +1 or +2 on immunohistochemistry without HER2 gene amplification by in situ hybridization) and had complete data on outcomes. Clinical and demographicdata were collected, such as age, menopausal status, Ki-67, hormone receptorexpression and others. Key outcomes from the study comprised pCR (defined as ypT0/TIs/ypN0), overall survival, and metastasis-free survival (MFS). Survival analyses were conducted through the semiparametric Kaplan-Meier method to assess OS and MFS by pCR status, considering BC diagnosis as the index date. Overall, 297 patients were eligible and 141 were included in the study after matching the HER2-low definition. The pCR was seen in 18 out of 141 patients (12.7%). The median overall survival was 8.2 years, and the median MFS was 2.7 years. The OS of pCR was 83.4% and non-pCR was 58.1%; the DFS of pCR was 55.5% and non-pCR 40.6%. This study gives updated insights on pCR, OS, and MFS in women with HER2-low BC exposed to NAC.

Prostate-Specific Membrane Antigen PET Response Associates with Metastasis-Free Survival After Stereotactic Ablative Radiation in Oligometastatic Prostate Cancer

PurposeEmerging data suggest metastasis-directed therapy (MDT) improves outcomes in patients with oligometastatic castration-sensitive prostate cancer (omCSPC). Prostate-specific membrane antigen positron emission tomography (PSMA-PET) can detect occult metastatic disease and has been proposed as a biomarker for treatment response. Herein we identify and validate a PSMA-PET biomarker for metastasis-free survival (MFS) following MDT in omCSPC. Methods and materialsWe performed an international multi-institutional retrospective study of patients with omCSPC, defined as ≤3 lesions, treated with metastasis-directed stereotactic ablative radiation therapy who underwent PSMA-PET/CT prior to and after (median 6.2 months, range 2.4-10.9 months) treatment. Pre- and post-MDT PSMA-PET/CT SUVmax was measured for all lesions and PSMA response was defined as percent change in SUVmax of the least responsive lesion. PSMA response was evaluated as both a continuous variable and dichotomized as PSMA responders with a complete/partial response (at least 30% reduction in SUVmax) and PSMA non-responders with stable/progressive disease (less than a 30% reduction in SUVmax). PSMA response was correlated conventional imaging defined metastasis-free survival (MFS) with Kaplan-Meier and cox regression. ResultsA total of 131 patients with 261 treated metastases were included in the analysis, with median follow-up of 29 months (IQR 18.5-41.3). Following SABR, 70.2% of patients were classified as PSMA responders. Multivariable analysis demonstrated PSMA response as a continuous variable was associated with significantly worse MFS (HR=1.003, 95%CI 1.001-1.006; p=0.016). Patients classified as PSMA responders were found to have significantly improved median MFS of 39.9 vs 12 months (p=0.001) compared to PSMA non-responders. Our study is limited as it is a retrospective review of a heterogenous population. ConclusionsFollowing SABR, PSMA-PET response appears to be a radiographic biomarker that correlates with MFS in omCSPC. This approach holds promise for guiding clinical management of omCSPC and should be validated in a prospective setting.

Neoadjuvant Cisplatin-Based Chemotherapy Followed by Selective Bladder Preservation Chemoradiotherapy in Muscle-Invasive Urothelial Carcinoma of the Bladder: Post Hoc Analysis of Two Prospective Studies.

Bladder preservation chemoradiotherapy (CRT) in patients with a clinical complete response (cCR) following cisplatin-based neoadjuvant chemotherapy (NAC) is a promising treatment strategy for muscle-invasive bladder urothelial carcinoma (MIBC). A combined analysis of raw data from two prospective phase II studies was performed to better evaluate the feasibility of selective bladder preservation CRT. The analysis was based on primary efficacy data from two independent studies, including 76 MIBC patients receiving NAC followed by bladder preservation CRT. The efficacy data included metastasis-free survival (MFS) and disease-free survival (DFS). For the present analysis, starting point of survival was defined as the date of commencing CRT. Among 76 patients, 66 had a cCR following NAC. Sixty-four patients received gemcitabine and cisplatin (GC) combination chemotherapy in neoadjuvant setting, and 12 received nivolumab plus GC. Bladder preservation CRT following NAC was generally well-tolerated, with low urinary tract symptoms being the most common late complication. With a median follow-up of 64 months, recurrence was recorded in 43 patients (57%): intravesical only (n=20), metastatic only (n=16), and both (n=7). In 27 patients with intravesical recurrence, transurethral resection, and Bacillus Calmette-Guerin treatment was given to 17 patients. Salvage cystectomy was performed in 10 patients. Median DFS was 46.3 (95% confidence interval [CI], 25.1 to 67.5) months, and the median MFS was not reached. Neither DFS nor MFS appeared to be affected by any of the baseline characteristics. However, DFS was significantly longer in patients with a cCR than in those without (hazard ratio, 0.465; 95% CI, 0.222 to 0.976). The strategy of NAC followed by selective bladder preservation CRT based on the cCR is feasible in the treatment of MIBC. A standardized definition of cCR is needed to better assess disease status post-NAC.

Adjuvant Chemotherapy for Upper Tract Urothelial Carcinoma: A Real-World, Retrospective Study.

The aim of this retrospective study was to evaluate the efficacy of adjuvant cisplatin-based chemotherapy in patients with locally advanced upper tract urothelial carcinoma (UTUC), administered following radical nephroureterectomy. Patients with UTUC, arising from renal pelvis or ureter, staged pT3/T4 or N+ were treated with adjuvant chemotherapy following surgery. The chemotherapy consisted of gemcitabine 1,000 mg/m2 on days 1 and 8, cisplatin 70 mg/m2 on day 1. Treatment was repeated every 3 weeks for up to 4 cycles. Endpoints included disease-free survival (DFS), metastasis-free survival (MFS), and safety. Among 89 eligible patients, 85 (95.5%) completed at least 3 cycles of adjuvant chemotherapy. Chemotherapy was well tolerated, the main toxicities being mild-to-moderate gastrointestinal toxic effects and pruritus. With a median follow-up of 37 months, median DFS was 30 months (95% confidence interval, 22 to 39), and the median MFS was not reached. The 3-year DFS and MFS were 44% and 56%, respectively. Multivariate analyses revealed that the main factor associated with DFS and MFS was the lymph node involvement, whereas age, T category, grade, or the primary site of UTUC were not significantly associated with DFS or MFS. Adjuvant cisplatin-based chemotherapy after radical surgery of pT3/T4 or N+ UTUC was feasible and may demonstrate benefits in DFS and MFS. Whether novel agents added to the chemotherapy regimen, as a concurrent combination or maintenance, impacts on survival or reduces the development of metastases remains to be studied.

Stereotactic reirradiation with CyberknifeR for locally recurrent prostate cancer, long-term toxicity and clinical outcomes from a monocentric cohort.

Up to 47% of patients with localized prostate cancer (PCa) treated with radiotherapy (EBRT) eventually develop local recurrence. To date, no clear consensus exists on optimal management. A growing body of interest supports the use of stereotaxic re-irradiation (rSBRT), with promising oncological outcomes and low toxicity profile. We collected a single-center case series of locally recurrent PCa who underwent re-irradiation after a previous course of postoperative or definitive radiotherapy. Data from 101 patients treated at our institution for locally recurrent PCa from June 2012 to June 2021 were retrospectively collected. Patients underwent rSBRT with CyberKnife system (Accuray Inc., Sunnyvale, CA, USA), delivered to intraprostatic or macroscopic recurrences within the prostate bed, for a total dose of 30Gy in 5 fractions. All patients received prior EBRT. The median EQD2 total dose was 75.0Gy (range, 60-80Gy). Thirty-two (32%) patients were receiving androgen deprivation therapy (ADT) after prior biochemical recurrence. After a median follow-up of 57.8months, BR occurred in 55 patients (54.5%), with a median BR-free survival (BRFS) of 40.4months (95% C.I. 34.3-58.3). Thirty-two patients (31.7%) developed metastatic disease, with a median metastasis-free survival (MFS) not reached. PSA ≥ 2.5ng/ml and ADT were associated with worst BRFS (26.06 vs. 39.3months, p = 0.03 and 22.7 vs. 27months, p = 0.01, respectively). Castration-resistant status and ADT were found to be predictive of worst MFS (34.1 vs. 50.5months, p = 0.02 and 33.5 vs. 53.1months, p = 0.002, respectively). Concomitant ADT was confirmed as an independent factor for MFS (HR 4.8, 95% CI 1.5-10.6, p = 0.007). No grade > /2 adverse were recorded. After almost 5years of follow-up, with a median BRFS of 40.4months and no grade ≥ 2 AEs, CyberknifeR rSBRT proved effective and safe in a cohort of 101 patients affected by locally recurrent PCa.

Efficacy and safety outcomes of darolutamide in patients with non-metastatic castration-resistant prostate cancer with comorbidities and concomitant medications from the randomised phase 3 ARAMIS trial

PurposeIn patients with non-metastatic castration-resistant prostate cancer (nmCRPC) in the Androgen Receptor Antagonizing Agent for Metastasis-free Survival (ARAMIS) trial, darolutamide significantly improved median metastasis-free survival by nearly 2 years and reduced the risk of death by 31% versus placebo, with a favourable safety/tolerability profile. This post hoc analysis of ARAMIS evaluated efficacy and safety in patients by number of comorbidities and concomitant medications. MethodsPatients with nmCRPC were randomised 2:1 to darolutamide (n = 955) or placebo (n = 554) while continuing androgen-deprivation therapy. Overall survival (OS) and treatment-emergent adverse events (TEAEs) were evaluated in subgroups by median numbers of ongoing comorbidities and concomitant medications. HRs were determined from univariate analysis using Cox regression. FindingsMedian numbers of comorbidities and concomitant medications were 6 and 10, respectively, with 41.6% of patients having >6 comorbidities and 48.8% taking >10 concomitant medications. For patients with ≤ 6 and >6 comorbidities, darolutamide increased OS versus placebo (hazard ratio [HR] 0.65 and 0.73, respectively), and this benefit was consistent for cardiovascular, metabolic, and other comorbidities (HR range: 0.39–0.88). For patients taking ≤ 10 and >10 concomitant medications, increased OS was also observed with darolutamide versus placebo (HR 0.76 and 0.66, respectively), and the benefit was consistent across medication classes (HR range: 0.45–0.80). Incidences of TEAEs and TEAEs leading to treatment discontinuation with darolutamide were similar to placebo across subgroups by numbers of comorbidities and concomitant medications. ConclusionsThe OS benefit and safety of darolutamide remained consistent with that observed in the overall ARAMIS population, even in patients with high numbers of comorbidities or concomitant medications. ClinicalTrials.gov registrationNCT02200614. Tweetable abstractDarolutamide increased overall survival versus placebo, and incidences of most adverse events were similar between treatments in patients with ≤ 6 or >6 comorbidities and those taking ≤ 10 or >10 concomitant medications.

Apalutamid for treatment of nonmetastatic castration-resistant prostste cancer – case study

A special form of prostate cancer is non-metastatic castration-resistant prostate cancer. Patients with this form have rising prostate-specific antigen and castrate testosterone levels, with no radiological findings of metastatic disease on computed tomography and bone scan. The phase III trials demonstrated apalutamide, darolutamide or enzalutamide to be associated with a significantly longer median metastasis-free survival. The featured description presents one case of man with non-metastatic castration- resistant prostate cancer who was treated with apalutamide.

Nadir Prostate-specific Antigen as an Independent Predictor of Survival Outcomes: A Post Hoc Analysis of the PROSPER Randomized Clinical Trial.

This post hoc analysis of PROSPER evaluated the relationship between depth of PSA decline and clinical outcomes in enzalutamide-treated men with nonmetastatic castration-resistant prostate cancer. PROSPER was an international, randomized, double-blind, placebo-controlled, phase 3 trial that demonstrated significantly improved metastasis-free survival and overall survival with androgen deprivation therapy plus enzalutamide vs placebo. A total of 905 enzalutamide-treated men were included in this post hoc analysis. Metastasis-free survival (primary endpoint) and overall survival (secondary endpoint) were evaluated for 4 mutually exclusive subgroups defined by PSA decline: <50% (reference); ≥50% to <90%; ≥90%, nadir ≥0.2 ng/mL; and ≥90%, nadir <0.2 ng/mL. Medians and 95% confidence intervals were determined using a 12-month landmark analysis; hazard ratios and P values were based on an unstratified Cox proportional analysis model. In enzalutamide-treated men, PSA declines of <50%, ≥50% to <90%, ≥90% with nadir ≥0.2 ng/mL, and ≥90% with nadir <0.2 ng/mL were associated with median metastasis-free survival in months (95% confidence intervals) of 22.1 (14.8-not reached), 34.2 (29.4-not reached), 36.6 (33.4-not reached), and not reached, respectively, and overall survival in months (95% confidence intervals) of 40.8 (31.7-44.9), 54.4 (49.0-67.0), 64.3 (63.4-not reached), and not reached, respectively. There was a statistically significant correlation between greater depth of PSA decline and improved clinical outcomes, suggesting a previously underappreciated relationship between changes in PSA levels and clinical outcomes in nonmetastatic castration-resistant prostate cancer.

Neoadjuvant cisplatin-based chemotherapy followed by selective bladder preservation chemoradiotherapy (CRT) in muscle-invasive urothelial carcinoma of bladder (MIBC): A combined retrospective analysis of two prospective studies.

496 Background: Bladder preservation CRT in patients with a clinical complete response (cCR) following neoadjuvant cisplatin-based chemotherapy is one of the promising treatment strategies for MIBC. A combined analysis of raw data from two prospective phase II studies was performed to better evaluate the feasibility of selective bladder preservation CRT. Methods: The analysis was based on primary efficacy data from two independent studies, including 76 MIBC patients receiving neoadjuvant chemotherapy followed by bladder preservation CRT. The efficacy data included metastasis-free survival (MFS) and disease-free survival (DFS). For the present analysis, starting point of survivals was defined as the date of commencing CRT. Results: Sixty-four patients received gemcitabine/cisplatin (GC) combination chemotherapy in neoadjuvant setting, and 12 received nivolumab plus GC. After completion of planned neoadjuvant chemotherapy, 66 patients with a cCR and 10 who did not have a cCR but refused surgery were treated with CRT. With a median follow-up of 45 (95% CI, 41-48) months, a total of 39 recurrences was observed (51%): metastatic (n=28) and within the urinary tract (n=11). Median DFS or MFS was not reached. The 12- and 24-month DFS rates were 81% and 66%, respectively. MFS rates at 12- and 24-month were 87% and 75%, respectively. Both DFS (P=0.055) and MFS (P=0.014; HR 0.38; 95% CI, 0.17-0.85) appeared to be affected by the achievement of a cCR. Conclusions: The strategy of neoadjuvant chemotherapy followed by selective bladder preservation CRT based on the cCR is feasible in the treatment of MIBC.

Assessment of Tolerability, Response and Complications of Concurrent Chemoradiation With Capecitabine and Cisplatin in Muscle-Invasive Bladder Cancer; A Single Arm Study.

To evaluate the feasibility, tolerance and efficacy of cisplatin+capecitabine as a proposed combination in concurrent chemoradiotherapy for patients with muscle-invasive bladder cancer (MIBC). MIBC patients with stage T2-T4aN0M0 participated in this single-arm clinical trial. After maximal TURBT, 66Gy/33 daily fractions of radiation were administered with concurrent chemotherapy of cisplatin (35 mg/m2) and capecitabine (625 mg/m2). The primary endpoint was treatment tolerability, defined as receiving capecitabine+cisplatin combination for at least 5 weeks during radiation therapy. The secondary endpoints included complete response (CR) and acute toxicity rates. This study included 19 MIBC patients from 2018 to 2019. Eighteen patients (94.7%, 95%CI: 75.4-99.0) completed the planned treatment course. Only one patient (5.26%, 95%CI: 0.9-24.6) discontinued the treatment due to grade-3 GI toxicity. Among those who completed the treatment, CR was seen in 12 patients (66.7%, 95% CI=44.4-88.9) with no grade ≥ 3 toxicities. The most common grade-2 side effects during therapy were renal complications (57.9%), and the only grade-2 complication after therapy was urinary-related (11.1%). The median follow-up was 31 months and the median overall survival (OS) was 31 months. The 2-year OS was 78% (95% CI 58.4-97.6), Cystectomy-free survival was 61% (95% CI: 37.5-84.5), and the median OS after recurrence was 13 months. Distant metastases were the first type of recurrence in most patients with a recurrence, which occurred in 7 (36.8%) patients. Median metastasis-free survival (MFS) was 30 months, and 2-year MFS was 66% (95% CI:45-87). The promising tolerability rate seen with concurrent cisplatin+capecitabine in this study was comparable to the available literature. Thus, this combination concurrently with radiation warrants further studies in the context of chemoradiotherapy of MIBC.

Systemic Immunological Determinants of Oncological Outcomes After Surgery for Localized Renal Cell Carcinoma.

In systemic therapy trials, a decreasing neutrophil-to-lymphocyte ratio (NLR) after treatment for metastatic renal cell carcinoma (RCC) has been associated with improved oncologic outcomes. Paradoxically, for patients with localized RCC treated with upfront surgery the opposite effect has been reported. We thus aimed to evaluate NLR dynamics on localized RCC recurrence. Treatment naïve patients with localized RCC managed surgically between 2005 and 2020 were included. Preoperative NLR was calculated within 6-weeks prior to surgery and postoperative NLR was calculated between 4 and twelve-weeks after surgery. Patients were followed for disease recurrence, noting metastatic sites and postoperative infections. Cox regression were used to determine whether the relative change in postoperative NLR was associated with metastasis-free survival (MFS) and cancer-specific survival (CSS), adjusted for preoperative NLR. In the cohort of 3310 patients, 996 (30%) had postoperative NLR available. These patients generally had more advanced disease, with 100 developing metastases and 38 dying from kidney cancer. Median MFS follow-up was 4.4 years. Decreasing 2-month postoperative NLR was associated with non-statistically significant worse MFS and CSS (HR 0.79, 95% 0.50, 1.24, P=.3; HR 0.83, 95% C.I. 0.40, 1.73; P=.6). On sensitivity analysis, across all NLR measurements, with NLR as a time-dependent covariate, results were similar, with a declining NLR associated with adverse MFS (HR 0.85, 95% CI 0.69, 1.30, P-value=.10), though not meeting conventional levels of significance. In higher-risk localized RCC patients, postoperative NLR is not suitable as a biomarker for predicting recurrences.

Enzalutamide in patients with non-metastatic castration-resistant prostate cancer after combined androgen blockade for recurrence following radical treatment in Japan (Japanese research for patients with non-metastatic castration-resistant prostate cancer-enzalutamide: JCASTRE-zero)—a prospective single-arm interventional study

BackgroundThe effect of enzalutamide in patients with non-metastatic castration-resistant prostate cancer after combined androgen blockade, which represents a patient profile similar to real-world clinical practice in Japan, remains unknown. Therefore, we investigate the efficacy and safety of enzalutamide after combined androgen blockade for recurrence following radical treatment in Japanese patients with non-metastatic castration-resistant prostate cancer.MethodsWe analyzed 66 patients with non-metastatic castration-resistant prostate cancer after combined androgen blockade for recurrence following radical prostatectomy or radiation therapy who were prospectively enrolled from October 2015 to March 2018. They received enzalutamide 160 mg orally once daily until the protocol treatment discontinuation criteria were met. The primary endpoint was prostate-specific antigen-progression-free survival, defined as the time from enrollment to prostate-specific antigen-based progression or death from any cause. The secondary endpoints included overall survival, progression-free survival, metastasis-free survival, time to prostate-specific antigen progression, prostate-specific antigen response rate, chemotherapy-free survival, and safety assessment.ResultsThe median observation period was 27.3 months. The median prostate-specific antigen-progression-free survival was 35.0 months (95% confidence interval, 17.5 to not reached). The median overall survival, median progression-free survival, median metastasis-free survival, and chemotherapy-free survival were not reached, with the corresponding 2-year rates being 91.6%, 67.1%, 72.4%, and 85.8%, respectively. The 50% prostate-specific antigen response rate was 88.9%, with the median time being 2.8 months. In total, 42.2% of the patients experienced adverse events, with malaise being the most common.ConclusionsEnzalutamide effectively manages non-metastatic castration-resistant prostate cancer after combined androgen blockade for recurrence following radical treatment.Trialregistration: UMIN000018964, CRB6180007.

Is time to castration resistant prostate cancer a potential intermediate end-point for time to metastasis among men initiating androgen deprivation therapy for non-metastatic prostate cancer with rapid PSA doubling time (

Metastasis-free survival (MFS) is a surrogate for overall survival (OS) in men with non-metastatic castration-resistant prostate cancer (CRPC), but this endpoint may take years to develop in men with non-metastatic castrate-sensitive disease. The study objective was to examine whether progression to CRPC is a potential intermediate endpoint for developing metastatic disease in patients with biochemical recurrence (BCR) after radical prostatectomy (RP). Men with BCR following RP who had PSA doubling times (PSADT) < 9 months and no metastasis at the time of initiating androgen deprivation therapy (ADT) (n = 210) were included. The primary objective was to assess the correlation between CRPC-free survival (CRPC-FS) and MFS, and the secondary objective was to assess the correlation between time to metastasis and time to CRPC. Kendall's Tau was used to test the correlation for the primary and secondary outcomes. The median MFS was 104 months (95% CI: 83-114) and median CRPC-FS was 100 months (95% CI: 80-114). Based on the Kaplan-Meier curve, the greatest difference in time to MFS and CRPC-FS was around 70% free survival, which was reached at 61.2 months for MFS and 49.6 months for CRPC-FS. Kendall's Tau for the correlation between CRPC-FS and MFS and between time to CRPC and time to metastasis was 0.867 (95% CI: 0.765-0.968) and 0.764 (95% CI: 0.644-0.884), respectively. Given the high correlation between CRPC-FS and MFS, after validation, CRPC-FS may serve as a potential intermediate endpoint in trials for men with BCR initiating ADT following local therapy.

Abstract 3097: Patient-derived renal cell carcinoma xenografts engraftment identifies patients at risk of disease relapse, progression and death

Abstract Renal cell carcinoma (RCC) represents up to 90% of all kidney tumors, with 30% of patients presenting metastasis at diagnosis while 20-50% of those treated for curable localized disease experience recurrence. A better understanding of RCC biology is necessary to define the most efficient and personalized treatment or develop better antineoplastic drugs. Patient-derived xenografts (PDX) have emerged as one of the most promising approaches for that. This tool was generated by using surgical specimens of 87 patients implanted in immunodeficient NOD/SCID/gamma (NSG) mice, 17 of those subcutaneously and 70 at the renal subcapsular space. A total of 19 PDX developed only after orthotopic implantation and included 15 cases of clear cell RCC subtype, 3 cases of papillary subtype, and one unclassifiable tumor. One case of a PDX of a clear cell RCC recapitulated the phenotype of vena cava tumor thrombus extension that had been diagnosed in the source patient. The overall take rate was 27%, and the time to observed tumor growth varied from 5 to 13 months. An association between tumor growth and take rate was suggested by increasing take rates of 18%, 36%, and 100% among pT1 (pT1a + pT1b), pT3a, and pT3b stage tumors, respectively. PDX take rate was unrelated to tumor size (p =0.071). Patients whose tumor fragments engrafted experienced worse overall survival (OS) than those whose tumor fragments did not engraft (p = 0.003). Data also suggested a similar trend of association with metastasis-free survival (MFS) (p = 0.063). The median MFS for patients with successful PDX was 21.6 months (95% CI: 14.9, 28.3;), compared to a median of 34.4 months (95% CI: 30.4, 38.5 p = 0.003) among PDX engraftment-negative patients. PDX characterization by immunohistochemistry and targeted sequencing of the 21 most frequently mutated genes in the kidney indicated that all PDXs preserved RCC identity and major molecular alterations. From 19 PDX, the sequences of 13 patients’ tumor samples were compared with their respective PDX. In most patients (92% - 11/12), at least one mutation in patients’ tumor was identified in the PDX and in one case, no alterations were mapped. The most frequently mutated genes were VHL (50% - 6/12) and PBRM1 (41.7% - 5/12), followed by SETD2 (25% - 3/12), BAP1 and KDM5C (both 16.7% - 2/12), and ARID1A (8.3% - 1/12), indicating that all PDXs preserved RCC identity and major molecular alterations. These findings suggest that tumor engraftment capacity can identify patients at increased risk of relapse or death. Furthermore, pT1 stage tumors with the ability to engraft could also facilitate the identification of risk factors related to the rare pT1 cases with disease progression. These results suggest that the orthotopic xenograft model of RCC represents a suitable tool to study RCC biology, identify biomarkers, and test therapeutic candidates. Citation Format: Vilma Regina Martins, Adriano Beserra, Ethiene C. Estevan, Stephania Bezerra, Giovana T. Torrezan, Amanda Ikegani, Dellê Humberto, Isabela V. Cunha, Isabella T. Meira, Dirce M. Carraro, Primo N. Lara, Stenio Zequi, Tiago G. Santos. Patient-derived renal cell carcinoma xenografts engraftment identifies patients at risk of disease relapse, progression and death [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3097.

Prognostic value of vessels encapsulating tumor clusters (VETC) in sarcoma.

e23523 Background: How sarcoma metastasize is unknown. VETC has been described as an epithelial-to-mesenchymal-transition independent process of metastasis: endothelium covers neoplastic clusters allowing tumor dissemination. It has also been shown to be a predictive of tyrosine kinase inhibitors (TKI) response. The objectives of the present study are: 1) to assess the presence of VETC in sarcoma; 2) to model its prognostic role. Methods: The study was retrospective. We selected 54 cases of sarcomas (6 DDLPS, 10 GIST, 6 retroperitoneal LMS, 9 MLPS, 8 MPNST, 10 SFT, 5 UPS); of them 31 were metastatic (M1 group), 23 were not (M0 group, defined as least 5 years of negative follow-up). High risk GIST and SFT, and grade 3 FNCLCC were considered high grade. VETC was assessed with CD31 immunohistochemistry and defined as a continuous endothelial lining around tumor clusters. We used Bayesian probabilistic modeling to detect small effects and multilevel hierarchical modeling to reduce overfitting. Models were fit using Stan and R. CI were computed with the HPDI method for 89%. The whole posterior probability (PP) was used for calculations. Results: The two groups (M0 &amp; M1) were substantially homogeneous: the CI of the contrast PP (CPP) included 0 in each histology for sex, age, size, and grade; VETC was more expressed in M1 SFT cases with almost all the CPP mass above the 0. Also, UPS and GIST showed VETC to be more present in metastatic diseases with 79% and 78% respectively of the CPP mass above 0 (see table). Metastasis free survival (MFS) analysis showed that VETC in SFT and UPS with a coefficient of 2.42 (CI 0.73 – 4.65) and 1.94 (CI 0.16 – 3.67); for the latter the median was reached with a PP density of median MFS of 65 months (mo) (standard deviation, SD: 74 mo) for VETC- Vs 11 mo (SD: 14 mo) for VETC+. Similarly, disease specific survival analysis showed – in SFT and UPS – that VETC was negatively associated with prognosis with coefficients of 1.24 and 2.34; however the CI covered slightly the 0 (-0.54 – 3.96 and -0.09 – 5.73, respectively). Conclusions: We found VETC in sarcoma and highlighted its prognostic role in SFT and UPS. [Table: see text]

DARolutamide ObservationaL (DAROL) study in patients with nonmetastatic castration-resistant prostate cancer (nmCRPC).

e17029 Background: Darolutamide (DARO) is a structurally distinct and highly potent androgen receptor inhibitor that significantly increased median metastasis-free survival by ̃2 years and improved overall survival with a 31% reduction in risk of death vs placebo in men with nmCRPC in ARAMIS (NCT02200614), with a favorable tolerability profile. DARO significantly improved survival in men with metastatic hormone-sensitive prostate cancer (mHSPC) in ARASENS. The ongoing DAROL trial (NCT04122976) is designed to support results from the phase 3 ARAMIS study and to provide insight into the safety and effectiveness of DARO and the management of nmCRPC in the real-world setting. We report results of the first prespecified interim analysis. Methods: DAROL is an international, single-arm, non-interventional study. Eligible patients (pts) are DARO naïve, ≥18 years of age, with confirmed nmCRPC, for whom the decision to treat with DARO was made before enrollment. Treatment dose and duration are per investigator’s routine practice. The primary endpoint is safety, including treatment-emergent adverse events (TEAEs). Prostate-specific antigen (PSA) response was an exploratory objective. Descriptive statistics are reported for the first prespecified interim analysis (cut-off: September 23, 2021) performed after ̃100 pts (from US, Canada, Japan) completed ≥6 months of treatment or discontinued treatment. Results: All 100 pts were evaluable for safety: median age 78.0 years; White/Black/Asian/other/not reported, 59%/11%/27%/1%/2%; North America/Asia Pacific, 79%/21%; baseline ECOG performance status 0–1/2–4/not reported, 72%/5%/23%; median (Q1–Q3) time from initial diagnosis to castration-resistant, 89.1 mo (39.1–130.6 mo); Gleason score at initial diagnosis ≤6/7/8–10, 15.8%/38.9%/45.3%; baseline PSA ≤10/ &gt; 10 ng/mL, 75.3%/24.7%; PSA doubling time ≤6/ &gt; 6 mo, 58.2%/41.8%. Median (Q1–Q3) duration of treatment was 11.3 mo (8.4–14.4 mo); median (Q1–Q3) follow-up time was 12.3 mo (9.6–15.6 mo). Median starting dose and daily treatment dose was 1200 mg daily. 28% of pts had TEAEs of any grade, with 3% grade 3; no grade ≥4. 2% of pts had serious adverse events (AEs). Incidence rates of AEs were generally low, consistent with the safety profile observed in ARAMIS, and those that occurred in ≥2% of pts were fatigue (5%), diarrhea (5%), asthenia (2%), muscle weakness (2%), anemia (2%), and rash (including rash pruritic, 2%). TEAEs led to permanent study drug discontinuation in 7% of pts. Of 93 pts evaluable for efficacy, the percentage with a PSA response of ≥30%, ≥50%, and ≥90% at any time during follow-up was 81.7%, 77.4% and 52.7%, respectively. Conclusions: At the first interim analysis of the DAROL observational study in the real-world setting, the safety and tolerability of DARO was consistent with the favorable tolerability profile observed in the randomized ARAMIS trial. Clinical trial information: NCT04122976.

Stereotactic Radiotherapy for Lesions Detected via 68Ga-Prostate-specific Membrane Antigen and 18F-Fluorodexyglucose Positron Emission Tomography/Computed Tomography in Patients with Nonmetastatic Prostate Cancer with Early Prostate-specific Antigen Progression on Androgen Deprivation Therapy: A Prospective Single-center Study

BackgroundDual-tracer positron emission tomography/computed tomography (PET/CT) with a 68Ga-labelled prostate-specific membrane antigen (PSMA) ligand and 18F-fluorodeoxyglucose (FDG) improves detection of metastatic heterogeneity and burden in patients with nonmetastatic prostate cancer (nmPCa). However, there is limited prospective evidence regarding its impact on the efficacy of stereotactic body radiotherapy (SBRT). ObjectiveTo evaluate metastasis-free survival (MFS) and toxicity after SBRT to dual-tracer PET/CT-detected metastases in patients with nmPCa and early prostate-specific antigen (PSA) progression on androgen deprivation therapy (ADT; PSA ≤2 ng/ml). Design, setting, and participantsPatients were prospectively screened using dual-tracer PET/CT between April 2019 and October 2020. SBRT was recommended for patients with five or fewer nonvisceral metastases (SBRT group). Patients without detectable metastases (N−/M− group) and those who refused SBRT (ADT group) continued to receive ADT. Patients were followed with conventional imaging. InterventionSBRT to each PET/CT-detected metastasis. Outcome measurements and statistical analysisKaplan-Meier methods were used to determine MFS. Toxicity was evaluated using Common Terminology Criteria for Adverse Event v4.0. Results and limitationsSeventy-four consecutive patients were screened. The median PSA and PSA doubling time were 0.59 ng/ml and 4.56 mo, respectively. Overall, 54 patients had metastases and 17 had PSMA-/FDG+ disease. Seven patients were excluded from the MFS analysis, including two with a history of abiraterone treatment and five with more than five metastases. The median follow-up was 21.4 mo. The ADT group had shorter MFS than the SBRT group (11.0 mo vs not reached; hazard ratio [HR] 4.69, 95% confidence interval [CI] 2.92–25.0; p < 0.001) and the N−/M− group (11.0 mo vs not reached; HR 8.78, 95% CI 4.04–40.30; p < 0.001). There was no significant difference in median MFS between the SBRT group and the N−/M− group (p = 0.261). A PSA response >90% was achieved by 86% of patients in the SBRT group. There were no grade ≥3 adverse events after SBRT. The nonrandomized design is the major study limitation. ConclusionsDual-tracer PET/CT-guided SBRT delivered superior local control rates in comparison to ADT alone and had minimal toxicity. Patient summaryWe investigated metastasis-targeted radiotherapy for patients with up to five prostate cancer metastases detected with two different radioisotope scans. Our results show that this approach yields promising metastasis-free survival and low toxicity.

Long-Term Outcomes of a Phase I Trial of Weekly Docetaxel, Total Androgen Blockade, and Image Guided Intensity Modulated Radiation Therapy for Localized High-Risk Prostate Adenocarcinoma

PurposeOur purpose was to describe the long-term outcomes seen with the addition of concurrent weekly docetaxel to high-dose intensity modulated radiation (IMRT) to the prostate and androgen deprivation therapy in patients with high-risk nonmetastatic adenocarcinoma of the prostate. Methods and MaterialsNineteen patients with high-risk, localized prostate cancer were treated in a phase I trial with concurrent docetaxel at doses of 10 to 30 mg/m2, in a dose-escalated scheme, in addition to IMRT (77.4 Gy/43 fx) and neoadjuvant and concurrent combined androgen blockade (gonadotropin-releasing hormone agonist and antiandrogen). A gonadotropin-releasing hormone agonist was continued for an additional 24 months post radiation. Kaplan-Meier analysis was used to estimate the survival probabilities. ResultsAt a median follow-up of 10.5 years, 5-year and 10-year overall survival were found to be 89.5% and 68.4%, respectively. The median metastasis-free survival and progression-free survival were determined to be 11.3 years and 9.0 years, respectively. ConclusionsThis regimen produced a 10-year overall survival of 68% with a 10-year metastasis-free survival of 58%. Grade >2 toxicity was minimal. These limited data suggest that the addition of concurrent weekly docetaxel to high-dose IMRT for high-risk prostate cancer warrants further investigation.

Analysis of the role of PI3K-AKT and DNA damage repair (DDR) genomic biomarkers as predictors of clinical outcomes in nonmetastatic castration-resistant prostate cancer (nmCRPC).

175 Background: Clinically relevant outcomes in nmCRPC treated with androgen receptor-axis-targeted therapies (ARAT) may be inferior in patients with tumors harboring mutations bypassing androgen receptor signalling. This final update of a retrospective, multicenter analysis explores the association between genomic mutations in the PI3K-AKT and DDR signalling pathways with ARAT treatment outcomes in nmCRPC patients. Methods: Relevant clinical endpoint were collected for high-risk nmCRPC patients treated with an ARAT at APCaRI affiliated cancer centers, including median metastasis-free survival (MFS), overall survival (OS), PSA decline ≥ 50% (PSA50), and second progression free survival (PFS2). Archival tumor tissue was accessed for next generation gene sequencing, examining for genomic alterations in 500 genes, including those involved in the DDR and the PI3K-AKT signalling pathways. Comparison of outcomes of patients with DDR and PI3K-AKT pathway mutations was conducted using Cox proportional hazards regression using wildtype cases as the reference group, adjusting for PSA doubling time and pelvic lymphadenopathy. Results: Of the 37 patients included, 30 (82%) received apalutamide, 5 (13%) received darolutamide, and 2 (6%) received enzalutamide. 10 patients (27%) had PI3K-AKT pathway mutations (4 PTEN, 3 PIK3Ca, 2 PIK3C2G, 1 PIK3C2b), 8 patients (22%) had DDR gene mutations (3 ATM, 2 CHEK1, 1 BRCA2, 1 CDK12, 1 CHEK2, 1 FANCD2, 1 FANCL), and 1 patient (3%) had 2 MLH1 mutations (microsatellite instability). Of those who had subsequent treatment, 1 received enzalutamide and 5 received abiraterone. Patients with PI3K-AKT pathway mutations had significantly shorter MFS (4.8 mo; HR 4.2; 95% CI 1.2 – 15.0; p = 0.025). Those with DDR mutations had a trend towards shorter MFS (23.3 mo HR 3.7; 95% CI 0.71 – 13.4; p = 0.134). OS data remains immature. 4 (11%) patients did not achieve PSA50, including a patient with 2 MLH1 mutations. Conclusions: This final analysis demonstrates that nmCRPC with PI3K and DDR signalling pathway mutations have poor clinical outcomes when treated with ARAT, likely secondary to decreased reliance on the androgen receptor signalling pathway. These results highlight the potential value of exploring targeted therapies, such as PARP or AKT inhibitors in patients with these mutations.

Stereotactic Re-irradiation in Recurrent Prostate Cancer after Previous Postoperative or Definitive Radiotherapy: Long-term Results after a Median Follow-up of 4 Years

AimsIn 2018, we published early results from a cohort of patients treated with stereotactic body radiotherapy (SBRT) after previous radiotherapy with definitive or postoperative intent. We sought to provide extended follow-up of this cohort to confirm the safety and efficacy of this approach in a real-world scenario. Materials and methodsFifty patients affected by local relapse after previous definitive or postoperative radiotherapy were treated with SBRT. Treatment provided a total dose of 30 Gy in five fractions. Data about biochemical relapse-free survival (BRFS) and metastasis-free survival (MFS), together with adverse events, were analysed. Toxicity was reported according to Common Terminology Criteria for Adverse Events (CTCAE) score v.4.03. ResultsAfter a median follow-up of 48.2 months, the median BRFS was 43 months. A Gleason score >7 and concomitant androgen deprivation therapy were shown to be predictors of the worst BRFS (hazard ratio 2.42, 95% confidence interval 1.09–5.41, P = 0.02; hazard ratio 2.83, 95% confidence interval 1.17–6.8, P = 0.02, respectively). The median MFS was not reached; concomitant androgen deprivation therapy was confirmed to be predictive of the worst MFS (hazard ratio 4.75, 95% confidence interval 1.52–14.8, P = 0.007). Late grade 1 and 2 rectal and bladder toxicity occurred in three (6%) and 13 (26%) patients, respectively. One patient experienced both grade 3 acute and chronic bladder toxicity. ConclusionSalvage SBRT re-irradiation after previous postoperative or definitive radiotherapy for local prostate cancer recurrence confirmed promising results in terms of oncological outcomes and the safety of this approach.