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Abstract Background Intermediate clinical endpoints (ICEs) prognostic for overall survival (OS) are needed for men receiving postprostatectomy radiation therapy (PORT) to improve clinical trial design. Objective To identify a potential ICE for men receiving PORT. Design, setting, and participants We performed an institutional review board–approved multi-institutional retrospective study of 566 men consecutively treated with PORT at tertiary care centers from 1986 to 2013. The median follow-up was 8.2 yr. Outcome measurements and statistical analysis Biochemical failure (BF), distant metastases (DM), and castrate-resistant prostate cancer (CRPC) were evaluated for correlation with OS and assessed as time-dependent variables in a multivariable Cox proportional hazards model and in landmark analyses at 1, 3, 5, and 7 yr after PORT. Cross-validated concordance (c) indices were used to assess model discrimination. Results and limitations OS at 1, 3, 5, and 7 yr after PORT was 98%, 95%, 90%, and 82%, respectively. In a time-varying model controlling for clinical and pathologic variables, BF (hazard ratio [HR] 2.32, 95% confidence interval [CI] 1.45–3.71; p < 0.001), DM (HR 6.52, 95% CI 4.20–10.1; p < 0.001), and CRPC (HR 2.47, 95% CI 1.56–3.92; p < 0.001) were associated with OS. In landmark analyses, 5-yr DM had the highest c index when adjusting for baseline covariates (0.78), with 5-yr DM also providing the greatest increase in discriminatory power over a model only including baseline covariates. These findings require validation in prospective randomized data. Conclusions While limited by the retrospective nature of the data, 5-yr DM is associated with lower OS following PORT, outperforming the prognostic capability of BF and CRPC at 1, 3, 5, or 7 yr after treatment. Confirmation of this ICE as a surrogate for OS is needed from randomized trial data so that it can be incorporated into future clinical trial design. Patient summary We assessed potential intermediate clinical endpoints prognostic for overall survival in a cohort of men receiving radiotherapy after prostatectomy. We identified the development of metastatic disease within 5 yr after treatment as the strongest predictor of overall survival. Take Home Message We assessed potential intermediate clinical endpoints prognostic for overall survival in a cohort of men receiving radiotherapy after prostatectomy. We identified the development of metastatic disease within 5 yr after treatment as the strongest predictor of overall survival. [ABSTRACT FROM AUTHOR]

Background Outcomes with postprostatectomy salvage radiation therapy (SRT) are not ideal. Little evidence exists regarding potential benefits of adding whole pelvic radiation therapy (WPRT) alone or in combination with androgen deprivation therapy (ADT). Objective To explore whether WPRT and/or ADT added to prostate bed radiation therapy (PBRT) improves freedom from biochemical failure (FFBF) or distant metastases (DM). Design, setting, and participants A database was compiled from 10 academic institutions of patients with postprostatectomy prostate-specific antigen (PSA) >0.01 ng/ml; pT1-4, Nx/0, cM0; and Gleason score (GS) ≥7 treated between 1987 and 2013. Median follow-up was 51 mo. Interventions WPRT and/or ADT in addition to PBRT. Outcome measurements and statistical analyses FFBF and DM were calculated using cumulative incidence estimation. Multivariable analysis (MVA) utilized cumulative incidence regression. Results and limitation Median pre-SRT PSA was 0.5 ng/ml for 1861 patients. Median follow-up for patients not experiencing biochemical failure (BF) was 55 mo. MVA showed increased BF for PBRT versus WPRT (hazard ratio [HR] 1.82, p < 0.001) and no ADT versus ADT (HR 1.70, p < 0.001). WPRT was associated with a 5-yr FFBF of 62% versus 49% ( p < 0.001) for PBRT. ADT use was associated with improved 5-yr FFBF (55% vs 50%, p = 0.012). No significant differences in DM cumulative incidence were found. Conclusions For patients with GS ≥7 receiving SRT, clinicians should weigh FFBF benefits of WPRT and ADT against toxicities. Future studies should explore the impact of WPRT on quality of life, clinical progression, and overall survival. Patient summary We evaluated patients with prostate cancer treated with radiation after surgery to remove the prostate. Both radiation to the pelvic lymph nodes and suppression of testosterone lowered the chance of increasing prostate-specific antigen (a marker for cancer returning). [ABSTRACT FROM AUTHOR]

Purpose: To assess the utility of circulating serum microRNAs (c-miRNAs) to predict response to high-dose radiation therapy for locally advanced non-small cell lung cancer (NSCLC).Methods and Materials: Data from 80 patients treated from 2004 to 2013 with definitive standard- or high-dose radiation therapy for stages II-III NSCLC as part of 4 prospective institutional clinical trials were evaluated. Pretreatment serum levels of 62 miRNAs were measured by quantitative reverse transcription-polymerase chain reaction array. We combined miRNA data and clinical factors to generate a dose-response score (DRS) for predicting overall survival (OS) after high-dose versus standard-dose radiation therapy. Elastic net Cox regression was used for variable selection and parameter estimation. Model assessment and tuning parameter selection were performed through full cross-validation. The DRS was also correlated with local progression, distant metastasis, and grade 3 or higher cardiac toxicity using Cox regression, and grade 2 or higher esophageal and pulmonary toxicity using logistic regression.Results: Eleven predictive miRNAs were combined with clinical factors to generate a DRS for each patient. In patients with low DRS, high-dose radiation therapy was associated with significantly improved OS compared to treatment with standard-dose radiation therapy (hazard ratio 0.22). In these patients, high-dose radiation also conferred lower risk of distant metastasis and local progression, although the latter association was not statistically significant. Patients with high DRS exhibited similar rates of OS regardless of dose (hazard ratio 0.78). The DRS did not correlate with treatment-related toxicity.Conclusions: Using c-miRNA signature and clinical factors, we developed a DRS that identified a subset of patients with locally advanced NSCLC who derive an OS benefit from high-dose radiation therapy. This DRS may guide dose escalation in a patient-specific manner. [ABSTRACT FROM AUTHOR]

Background and purpose Current methods to estimate risk of radiation-induced lung toxicity (RILT) rely on dosimetric parameters. We aimed to improve prognostication by incorporating clinical and cytokine data, and to investigate how these factors may interact with the effect of mean lung dose (MLD) on RILT. Materials and methods Data from 125 patients treated from 2004 to 2013 with definitive radiotherapy for stages I-III NSCLC on four prospective clinical trials were analyzed. Plasma levels of 30 cytokines were measured pretreatment, and at 2 and 4 weeks midtreatment. Penalized logistic regression models based on combinations of MLD, clinical factors, and cytokine levels were developed. Cross-validated estimates of log-likelihood and area under the receiver operating characteristic curve (AUC) were used to assess accuracy. Results In prognosticating grade 3 or greater RILT by MLD alone, cross-validated log-likelihood and AUC were −28.2 and 0.637, respectively. Incorporating clinical features and baseline cytokine levels increased log-likelihood to −27.6 and AUC to 0.669. Midtreatment cytokine data did not further increase log-likelihood or AUC. Of the 30 cytokines measured, higher levels of 13 decreased the effect of MLD on RILT, corresponding to a lower odds ratio for RILT per Gy MLD, while higher levels of 4 increased the association. Conclusions Although the added prognostic benefit from cytokine data in our model was modest, understanding how clinical and biologic factors interact with the MLD-RILT relationship represents a novel framework for understanding and investigating the multiple factors contributing to radiation-induced toxicity. [ABSTRACT FROM AUTHOR]