Challenges and opportunities for early phase clinical trials of novel drug-radiotherapy combinations: recommendations from NRG Oncology, the American Society for Radiation Oncology (ASTRO), the American College of Radiology (ACR), the Sarah Cannon Research Institute, and the American College of Radiation Oncology (ACRO).

NRG Oncology's Developmental Therapeutics and Radiation Therapy Subcommittee assembled an interdisciplinary group of investigators to address barriers to successful early phase clinical trials of novel combination therapies involving radiation. This Policy Review elucidates some of the many challenges associated with study design for early phase trials combining radiotherapy with novel systemic agents, which are distinct from drug-drug combination development and are often overlooked. We also advocate for potential solutions that could mitigate or eliminate some of these barriers, providing examples of specific clinical trial designs that could help facilitate efficient and effective evaluation of novel drug-radiotherapy combinations.

Malpractice Trends Involving Active Surveillance Across Cancers.

OBJECTIVE: To characterize malpractice trends related to active surveillance (AS) as a treatment strategy across cancers. BACKGROUND: Active surveillance is increasingly considered a viable management strategy for low-risk cancers. Since a subset of AS cases will progress, metastasize, or exhibit cancer-related mortality, a significant barrier to implementation is the perceived risk of litigation from missing the window for cure. Data on malpractice trends across cancers are lacking. METHODS: Westlaw Edge and LexisNexis Advance databases were searched from 1990 to 2022 for malpractice cases involving active surveillance in conjunction with thyroid cancer, prostate cancer, kidney cancer, breast cancer, or lymphoma. Queries included unpublished cases, trial orders, jury verdicts, and administrative decisions. Data were compiled on legal allegations, procedures performed, and verdicts or settlements rendered. RESULTS: Five prostate cancer cases were identified that pertained to active surveillance. Two cases involved alleged deliberate indifference from AS as a management strategy but were ruled as following the appropriate standard of care. In contrast, 3 cases involved alleged physician negligence for not explicitly recommending AS as a treatment option after complications from surgery occurred. All cases showed documented informed consent for AS, leading to defense verdicts in favor of the physicians. No cases of AS-related malpractice were identified for other cancer types. CONCLUSIONS: To date, no evidence of successful malpractice litigation for active surveillance in cancer has been identified. Given the legal precedent detailed in the identified cases and increasing support across national guidelines, active surveillance represents a sound management option in appropriate low-risk cancers, with no increased risk of medicolegal exposure.

Comparative Proteomic Analysis of HPV(+) Oropharyngeal Squamous Cell Carcinoma Recurrence.

Deintensification therapy for human papillomavirus-related oropharyngeal squamous cell carcinoma (HPV(+) OPSCC) is under active investigation. An adaptive treatment approach based on molecular stratification could identify high-risk patients predisposed to recurrence and better select for appropriate treatment regimens. Collectively, 40 HPV(+) OPSCC FFPE samples (20 disease-free, 20 recurrent) were surveyed using mass spectrometry-based proteomic analysis via data-independent acquisition to obtain fold change and false discovery differences. Ten-year overall survival was 100.0 and 27.7% for HPV(+) disease-free and recurrent cohorts, respectively. Of 1414 quantified proteins, 77 demonstrated significant differential expression. Top enriched functional pathways included those involved in programmed cell death (73 proteins, p = 7.43 × 10-30), apoptosis (73 proteins, p = 5.56 × 10-9), ß-catenin independent WNT signaling (47 proteins, p = 1.45 × 10-15), and Rho GTPase signaling (69 proteins, p = 1.09 × 10-5). PFN1 (p = 1.0 × 10-3), RAD23B (p = 2.9 × 10-4), LDHB (p = 1.0 × 10-3), and HINT1 (p = 3.8 × 10-3) pathways were significantly downregulated in the recurrent cohort. On functional validation via immunohistochemistry (IHC) staining, 46.9% (PFN1), 71.9% (RAD23B), 59.4% (LDHB), and 84.4% (HINT1) of cases were corroborated with mass spectrometry findings. Development of a multilateral molecular signature incorporating these targets may characterize high-risk disease, predict treatment response, and augment current management paradigms in head and neck cancer.

Development and Validation of an Improved Pathological Nodal Staging System in Men with Prostate Cancer.

PURPOSE: Prostate cancer pathological nodal staging uses a single category for all node-positive patients. We sought to improve risk stratification by creating and validating a novel pathological nodal staging system incorporating number of metastatic lymph nodes (+LNs). MATERIALS AND METHODS: A total of 118,450 men who underwent radical prostatectomy for nonmetastatic prostate cancer in the National Cancer Database comprised our development cohort. Multivariable Cox proportional hazards analysis with restricted cubic splines was used to assess the nonlinear association between number of +LNs and overall mortality (OM). A novel staging system based on number of +LNs was derived by recursive partitioning analysis. The staging system was validated for prediction of OM and prostate-specific mortality in 105,568 men with nonmetastatic prostate cancer undergoing radical prostatectomy from the Surveillance, Epidemiology, and End Results database. Discrimination was assessed via Harrell's c-index. RESULTS: In multivariable Cox analysis, OM risk increased with higher number of +LNs up to 4 (HR 1.30 per each LN+, 95% CI 1.23-1.38), with a nonstatistically significant increase in risk (HR 1.05, 95% CI 0.99-1.11) beyond 4 +LN. In the development cohort, recursive partitioning analysis identified optimal cutoffs at 0 (N0: referent), 1 (N1: HR 1.40, 95% CI 1.25-1.58), 2 (N2: HR 1.67, 95% CI 1.40-1.99), 3-5 (N3a: HR 2.18, 95% CI 0.84-2.60) and ≥6 (N3b: HR 3.00, 95% CI 2.37-3.79) +LNs. In the validation cohort, these groups had markedly different 10-year OM (0+ LNs, N0: 15%; 1+ LN, N1: 35%; 2+ LNs, N2: 43%; 3-5 +LNs, N3a: 52%; and ≥6 +LNs, N3b: 59%; p <0.05) and prostate-specific mortality. The novel staging system improved survival classification over current staging for node-positive patients (optimism-corrected c-index 0.669 [95% CI 0.668-0.671] vs 0.649 [95% CI 0.648-0.651]). CONCLUSIONS: Pathological nodal staging in prostate cancer is improved with stratification by number of +LNs.

Nodal staging convergence for HPV- and HPV+ oropharyngeal carcinoma.

BACKGROUND: Modern disease staging systems have restructured human papillomavirus (HPV)-negative (HPV-) and HPV-positive (HPV+) oropharyngeal carcinoma (OPC) into distinct pathologic nodal systems. Given that quantitative lymph node (LN) burden is the dominant prognostic factor in most head and neck cancers, we investigated whether HPV- and HPV+ OPC warrant divergent pathologic nodal classification. METHODS: Multivariable Cox regression models of OPC surgical patients identified via U.S. cancer registry data were constructed to determine associations between survival and nodal characteristics. Nonlinear associations between metastatic LN number and survival were modeled with restricted cubic splines. Recursive partitioning analysis (RPA) was used to derive unbiased nodal schema. RESULTS: Mortality risk escalated continuously with each successive positive LN in both OPC subtypes, with analogous slope. Survival hazard increased by 18.5% (hazard ratio [HR], 1.19 [95% CI, 1.16-1.21]; P < .001) and 19.1% (HR, 1.19 [95% CI, 1.17-1.21]; P < .001), with each added positive LN for HPV- and HPV+ OPC, respectively, up to identical change points of 5 positive LNs. Extranodal extension (ENE) was an independent predictor of HPV- OPC (HR, 1.55 [95% CI, 1.20-1.99]; P < .001) and HPV+ OPC (HR 1.73 [95% CI, 1.36-2.20]; P < .001) mortality. In RPA for both diseases, metastatic LN was the principal nodal covariate driving survival, with ENE as a secondary determinant. Given the similarities across analyses, we propose a concise, unifying HPV-/HPV+ OPC pathologic nodal classification schema: N1, 1-5 LN+/ENE-; N2, 1-5 LN+/ENE+; N3, >5 LN+. CONCLUSION: HPV- and HPV+ OPC exhibit parallel relationships between nodal characteristics and relative mortality. In both diseases, metastatic LN number represents the principal nodal covariate governing survival, with ENE being an influential secondary element. A consolidated OPC pathologic nodal staging system that is based on these covariates may best convey prognosis. LAY SUMMARY: The current nodal staging system for oropharyngeal carcinoma (OPC) has divided human papillomavirus (HPV)-negative (HPV-) and HPV-positive (HPV+) OPC into distinct systems that rely upon criteria that establish them as separate entities, a complexity that may undermine the core objective of staging schema to clearly communicate prognosis. Our large-scale analysis revealed that HPV- and HPV+ pathologic nodal staging systems in fact mirror each other. Multiple analyses produced conspicuously similar nodal staging systems, with metastatic lymph node number and extranodal extension delineating the highest risk groups that shape prognosis. We propose unifying HPV- and HPV+ nodal systems to best streamline prognostication and maximize staging accuracy.

Prognostic Impact of Histologic Grade for Papillary Thyroid Carcinoma.

BACKGROUND: While numerous factors affect prognosis in papillary thyroid carcinoma (PTC), the comparative impact of histologic grade has not been well described. Moreover, indications for external beam radiation therapy (EBRT) remain imprecise. We evaluate clinicopathologic characteristics and outcomes for PTC stratified by grade. METHODS: We profiled histologic grade for PTC (well differentiated, moderately differentiated, poorly differentiated) via hospital (National Cancer Database) and population-based (Surveillance, Epidemiology, and End Results) registries. Cox regression was used to adjust for clinicopathologic covariates. Statistical interactions between subtypes and the effect of EBRT on survival were assessed. RESULTS: Collectively, worsening clinicopathologic factors (age, tumor size, extrathyroidal extension, nodal spread, M1 disease) and outcomes (disease-free survival, overall survival) correlated with less differentiated state, across all histologic grades (p < 0.001). Multivariable analysis showed escalating hazard with loss of differentiation relative to well-differentiated PTC (moderately differentiated hazard ratio [HR] 1.21, 95% confidence interval [CI] 1.04-1.41, p = 0.02; poorly differentiated HR 2.62, 95% CI 2.23-3.08, p < 0.001). Correspondingly, greater survival benefit was associated with EBRT for poorly differentiated cases (HR 0.36, 95% CI 0.18-0.72, p = 0.004). This finding was upheld after landmark analysis to address potential immortal time bias (HR 0.37, 95% CI 0.17-0.80, p = 0.01). CONCLUSIONS: Worsening histologic grade in PTC is independently associated with parallel escalation in mortality risk, on a scale approximating or surpassing established thyroid cancer risk factors. On preliminary analysis, EBRT was associated with improved survival in the most aggressive or least differentiated subvariants. Further investigation is warranted to examine the efficacy of EBRT for select poorly differentiated thyroid carcinomas.

Improved survival in women versus men with merkel cell carcinoma.

BACKGROUND: Studies have observed that women have better outcomes than men in melanoma, but less is known about the influence of sex differences on outcomes for other aggressive cutaneous malignancies. OBJECTIVE: To investigate whether women and men have disparate outcomes in Merkel cell carcinoma (MCC). METHODS: Patients with nonmetastatic MCC undergoing surgery and lymph node evaluation were identified from the National Cancer Database (NCDB) and the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier analysis and Cox proportional hazards regression models were used for overall survival, and competing-risks analysis and Fine-Gray models were used for cause-specific and other-cause mortality. RESULTS: The NCDB cohort (n = 4178) included 1516 (36%) women. Women had a consistent survival advantage compared with men in propensity score-matched analysis (66.0% vs 56.8% at 5 years, P < .001) and multivariable Cox regression (hazard ratio, 0.68; 95% confidence interval, 0.61-0.75; P < .001). Similarly, women had a survival advantage in the SEER validation cohort (n = 1202) with 457 (38.0%) women, which was entirely due to differences in MCC-specific mortality (5-year cumulative incidence: 16.4% vs 26.7%, P = .002), with no difference in other-cause mortality (16.8% vs 17.8%, P = .43) observed in propensity score-matched patients. LIMITATIONS: Potential selection bias from a retrospective data set. CONCLUSION: In MCC, women have improved survival compared with men, driven by MCC-related mortality.

Quantitative metastatic lymph node burden and survival in Merkel cell carcinoma.

BACKGROUND: Current lymph node (LN) staging for Merkel cell carcinoma (MCC) does not account for the number of metastatic LNs, which is a primary driver of survival in multiple cancers. OBJECTIVE: To determine the impact of the number of metastatic LNs on survival in MCC. METHODS: Patients with MCC undergoing surgery were identified from the National Cancer Database (NCDB). The association between metastatic LN number and survival was modeled with restricted cubic splines. A novel nodal classification system was derived by using recursive partitioning analysis. MCC patients undergoing surgery in the Surveillance, Epidemiology, and End Results (SEER) Program were used as validation cohort. RESULTS: Among 3670 patients in the NCDB, increasing metastatic LN number was associated with decreased survival (P < .001). Mortality risk increased continuously with each additional positive LN when using multivariable, nonlinear modeling. According to a novel staging system derived via recursive partitioning analysis, the hazard ratio for death in multivariable regression compared with patients without LN involvement was 1.24 (P = .049), 2.08 (P < .001), 3.24 (P < .001), and 6.13 (P < .001) for the proposed N1a (1-3 metastatic LNs with microscopic detection), N1b (1-3 metastatic LNs with macroscopic detection), N2 (4-8 metastatic LNs), and N3 (≥9 metastatic LNs), respectively. This system was validated in the SEER cohort and showed improved concordance compared with the American Joint Committee on Cancer, Eighth Edition. LIMITATIONS: Retrospective design. CONCLUSIONS: Number of metastatic LNs is the dominant nodal factor driving survival in patients with MCC.

Stage I HPV-positive oropharyngeal cancer: Should all patients receive similar treatments?

BACKGROUND: Patients with clinical stage I human papillomavirus (HPV)-positive oropharyngeal squamous cell cancer (OPSCC) according to the American Joint Committee on Cancer (AJCC) eighth edition classification comprise a heterogeneous group formerly classified as stage I to stage IVA according to the seventh edition of the AJCC classification. These patients historically were treated with disparate treatment regimens, particularly with respect to the use of concurrent chemotherapy. METHODS: The National Cancer Data Base was queried for patients with AJCC eighth edition clinical stage I HPV-positive OPSCC (AJCC seventh edition stage T1-2N0-2bM0) who were diagnosed from 2010 to 2014 and underwent definitive radiotherapy. Concurrent chemotherapy with definitive radiotherapy was defined as chemotherapy administered within 7 days of the initiation of radiotherapy. RESULTS: The current analysis included 4473 patients with HPV-positive stage I OPSCC with a median follow-up of 36.3 months. A total of 3127 patients (69.9%) received concurrent chemotherapy. Concurrent chemotherapy was found to be associated with improved overall survival on multivariable analyses (hazard ratio [HR], 0.782; 95% CI, 0.645-0.948 [P = .012]). The effect of chemotherapy on survival varied based on lymph node involvement (P for interaction = .001). Specifically, chemotherapy was associated with improved survival for patients with lymph node-positive stage I disease (stage III-IVA according to the AJCC seventh edition: HR, 0.682; 95% CI, 0.557-0.835 [P < .001]), but not for patients with N0 disease (stage I-II according to the AJCC seventh edition: HR, 1.646; 95% CI, 1.011-2.681 [P = .05]). Similar results were noted among propensity score-matched cohorts. CONCLUSIONS: Treatment with concurrent chemotherapy was associated with improved overall survival for patients with lymph node-positive, but not lymph node-negative, AJCC eighth edition stage I HPV-positive OPSCC undergoing definitive radiotherapy, thereby supporting different treatment paradigms for these patients.

The association between facility volume and overall survival in patients with Merkel cell carcinoma.

BACKGROUND: Merkel cell carcinoma is an uncommon malignancy often requiring multidisciplinary management. The purpose of this study was to determine whether high-volume facilities have improved outcomes in patients with Merkel cell carcinoma relative to lower-volume facilities. METHODS: A total of 5304 patients from the National Cancer Database with stage I-III Merkel cell carcinoma undergoing surgery were analyzed. High-volume facilities were the top 1% by case volume. Multivariable Cox regression and propensity score-matching were performed to account for imbalances between groups. RESULTS: Treatment at high-volume facilities (hazard ratio: 0.74; 95% confidence interval: 0.65-0.84, P < .001) was independently associated with improved overall survival (OS) in multivariable analyses. In propensity score-matched cohorts, 5-year OS was 62.3% at high-volume facilities vs 56.8% at lower-volume facilities (P < .001). Median OS was 111 months at high-volume facilities vs 79 months at lower-volume facilities. CONCLUSION: Treatment at high-volume facilities is associated with improved OS in Merkel cell carcinoma. Given the impracticality of referring all elderly patients with Merkel cell carcinoma to a small number of facilities, methods to mitigate this disparity should be explored.

Impact of insurance on survival in patients < 65 with head & neck cancer treated with radiotherapy.

OBJECTIVES: The United States has a heterogenous health insurance landscape for patients <65 years. We sought to characterise the impact of primary payer on overall survival (OS) in insured patients younger than 65 with head and neck squamous cell carcinoma (HNSCC) treated with definitive radiotherapy. DESIGN/STUDY/PARTICIPANTS: The National Cancer Database was queried for patients <65 years old diagnosed from 2004 to 2014 undergoing definitive radiotherapy ± chemotherapy for cancers of the nasopharynx, oropharynx, hypopharynx and larynx. Uninsured patients and oropharyngeal cancers without known HPV status were excluded. MAIN OUTCOME: Overall survival. RESULTS: Overall, 27 292 insured patients were identified, including 17 060 (62.5%) with private insurance. Median follow-up was 52.1 months. In multivariable models, patients receiving Medicaid (HR = 1.66, 95% CI 1.57-1.75, P < .001), Medicare (HR = 1.64, 95% CI 1.55-1.73, P < .001) and other government insurance (HR = 1.44, 95% CI 1.29-1., P < .001) had independently increased mortality in comparison to those with private insurance. In propensity score-matched cohorts, 5-year OS was 65.5% vs 50.6% for privately vs government-insured patients, respectively (P < .001). In multivariable subgroup analysis, private insurance was associated with improved survival in all subgroups. However, the magnitude of this effect was most pronounced in patients with HPV-positive oropharyngeal cancer vs non-HPV-related cancer (interaction P < .001), younger patients (interaction P = .001), and those without comorbidity (interaction P < .001). CONCLUSIONS: Patients <65 with HNSCC undergoing definitive radiation with private health insurance have markedly longer survival relative to patients with government-sponsored insurance. This illustrates that increasing access to care may be necessary, but is not sufficient, to mitigate the significant disparities in the US healthcare system.

International Multicenter Validation of an Intermediate Risk Subclassification of Prostate Cancer Managed with Radical Treatment without Hormone Therapy.

PURPOSE: The NCCN Guidelines® recently endorsed a subclassification of intermediate risk prostate cancer into favorable and unfavorable subgroups. However, this subclassification was developed in a treatment heterogeneous cohort. Thus, to our knowledge the natural history of androgen deprivation treatment naïve favorable and unfavorable intermediate risk prostate cancer cases remains unknown. MATERIALS AND METHODS: Groups at 3 academic centers pooled data on patients with intermediate risk prostate cancer treated with radical monotherapy (dose escalated external beam radiotherapy, brachytherapy or radical prostatectomy) without combined androgen deprivation treatment. We used the cumulative incidence with competing risk analysis to estimate biochemical recurrence, distant metastasis and prostate cancer specific mortality. RESULTS: A total of 2,550 men at intermediate risk were included in study, of whom 1,063 and 1,487 were at favorable and unfavorable risk, respectively. Of the men 1,149 underwent radical prostatectomy, 1,143 underwent dose escalated external beam radiotherapy and 258 underwent brachytherapy. Median followup after the different treatments ranged from 60.4 to 107.4 months. The 10-year cumulative incidence of distant metastasis in the favorable vs unfavorable risk groups was 0.2% (95% CI 0.2-0.2) vs 11.6% (95% CI 7.7-15.5) for radical prostatectomy (p <0.001), 2.8% (95% CI 0.8-4.8) vs 13.5% (95% CI 9.6-17.4) for dose escalated external beam radiotherapy (p <0.001) and 3.5% (95% CI 0-7.4) vs 10.2% (95% CI 4.3-16.1) for brachytherapy (p = 0.063). The 10-year rate of prostate cancer specific mortality in the favorable vs unfavorable risk groups was 0% (95% CI 0-0) vs 3.7% (95% CI 1.7-5.7) for radical prostatectomy (p = 0.016), 0.5% (95% CI 0.5-0.5) vs 5.6% (95% CI 3.6-7.6) for dose escalated external beam radiotherapy (p = 0.015) and 0% (95% CI 0-0) vs 2.5% (95% CI 0.5-4.5) for brachytherapy (p = 0.028). CONCLUSIONS: This multicenter international effort independently validates the prognostic value of the intermediate risk prostate cancer subclassification in androgen deprivation treatment naïve cases across all radical treatment modalities. It is unlikely that treatment intensification would meaningfully improve oncologic outcomes in men at favorable intermediate risk.

Development of a novel salivary gland cancer lymph node staging system.

BACKGROUND: Current lymph node (LN) staging for salivary gland cancer (SGC) is extrapolated from mucosal head and neck squamous cell carcinoma. However, given its unique biology and clinical behavior, it is possible that a SGC-specific LN staging system would be more accurate. METHODS: Patients from the National Cancer Data Base with nonmetastatic SGC of the head and neck who were diagnosed from 2004 through 2013 and underwent surgical resection and neck dissection removing at least 10 LNs were included. Multivariable models were constructed to assess the association between survival and LN factors, including number of metastatic LNs, extranodal extension, LN size, and lower LN involvement. RESULTS: Overall, 4520 patients met the inclusion criteria. An increasing number of metastatic LNs was found to be strongly associated with worse survival without plateau. The risk of death increased more rapidly up to 4 LNs (hazard ratio, 1.34; 95% confidence interval, 1.27-1.41 [P < .001]), and was more gradual for additional LNs >4 (hazard ratio, 1.02; 95% confidence interval, 1.01-1.03 [P < .001]). LN size, extranodal extension, and lower LN involvement appeared to have no impact on survival when accounting for the number of metastatic LNs. Recursive partitioning analysis was used to create a novel SGC LN staging system in which N0 indicates 0 positive LNs, N1 indicates 1 to 2 positive LNs, N2 indicates 3 to 21 positive LNs, and N3 indicates ≥ 22 positive LNs. This system exhibited greater concordance than the current American Joint Committee on Cancer (eighth edition) system. CONCLUSIONS: Quantitative LN burden is an important determinant of survival in patients with SGC. Use of this variable may improve SGC staging. Cancer 2018. © 2018 American Cancer Society.

Quantitative survival impact of composite treatment delays in head and neck cancer.

BACKGROUND: Multidisciplinary management of head and neck cancer (HNC) must reconcile increasingly sophisticated subspecialty care with timeliness of care. Prior studies examined the individual effects of delays in diagnosis-to-treatment interval, postoperative interval, and radiation interval but did not consider them collectively. The objective of the current study was to investigate the combined impact of these interwoven intervals on patients with HNC. METHODS: Patients with HNC who underwent curative-intent surgery with radiation were identified in the National Cancer Database between 2004 and 2013. Multivariable models were constructed using restricted cubic splines to determine nonlinear relations with overall survival. RESULTS: Overall, 15,064 patients were evaluated. After adjustment for covariates, only prolonged postoperative interval (P < .001) and radiation interval (P < .001) independently predicted for worse outcomes, whereas the association of diagnosis-to-treatment interval with survival disappeared. By using multivariable restricted cubic spline functions, increasing postoperative interval did not affect mortality until 40 days after surgery, and each day of delay beyond this increased the risk of mortality until 70 days after surgery (hazard ratio, 1.14; 95% confidence interval, 1.01-1.28; P = .029). For radiation interval, mortality escalated continuously with each additional day of delay, plateauing at 55 days (hazard ratio, 1.25; 95% confidence interval, 1.11-1.41; P < .001). Delays beyond these change points were not associated with further survival decrements. CONCLUSIONS: Increasing delays in postoperative and radiation intervals are associated independently with an escalating risk of mortality that plateaus beyond certain thresholds. Delays in initiating therapy, conversely, are eclipsed in importance when appraised in conjunction with the entire treatment course. Such findings may redirect focus to streamlining those intervals that are most sensitive to delays when considering survival burden. Cancer 2018. © 2018 American Cancer Society.

Erectile function after stereotactic body radiotherapy for localized prostate cancer.

OBJECTIVE: To elucidate the functional erection rate after prostate stereotactic body radiotherapy (SBRT) and to develop a comprehensive prognostic model of outcomes after treatment. PATIENTS AND METHODS: Between 2008 and 2013, 373 consecutive men with localized prostate cancer were treated with SBRT at a single academic institution as part of a prospective clinical trial or prospective registry. Prospective longitudinal patient-reported health-related quality of life (HRQoL) data was collected using the Expanded Prostate Cancer Index Composite (EPIC)-26 instrument. Functional erections were strictly defined as 'firm enough for intercourse' according to EPIC-26. Detailed comorbidity data were also collected. Logistic regression models were used to predict 24- and 60-month functional erection rates. Observed erection rates after SBRT were compared with those after other radiation therapies (external beam radiation therapy [EBRT] and brachytherapy) using prospectively validated models. RESULTS: The median (interquartile range) follow-up was 56 (37-73) months and the response rate at 2 years was 84%. For those with functional erections at baseline, 57% and 45% retained function at 24 and 60 months, respectively. On multivariable analysis for 24-month erectile function, significant variables included higher baseline sexual HRQoL (adjusted odds ratio [aOR] 1.55 per 10 points, 95% confidence interval [CI] 1.37-1.74; P < 0.001) and older age (aOR 0.66 per 10 years, 95% CI 0.43-1.00; P = 0.05). At 60 months, baseline HRQoL and age remained associated with erectile function, along with body mass index (aOR 0.45, 95% CI 0.26-0.78; P < 0.001). The 24- and 60-month models had excellent discrimination (c-index 0.81 and 0.84, respectively). Erection rates after SBRT were not statistically different from model-predicted rates after EBRT or brachytherapy for the whole cohort and the cohort with baseline erectile function. CONCLUSIONS: Intermediate- to long-term post-SBRT erectile function results are promising and not significantly different from other radiotherapy techniques. Clinicians can use our prognostic model to counsel patients regarding expected erectile function after SBRT.

Natural history of 'second' biochemical failure after salvage radiation therapy for prostate cancer: a multi-institution study.

OBJECTIVES: To describe the natural history of prostate cancer in men who experience a second biochemical recurrence (BCR) after salvage radiotherapy (SRT) after prostatectomy. PATIENTS AND METHODS: After undergoing SRT at one of two institutions between 1986 and 2013, 286 patients experienced a second BCR, defined as two rises in prostate-specific antigen (PSA) of ≥0.2 ng/mL above nadir. Event rates for distant metastasis (DM) or freedom from DM (FFDM), castration-resistant prostate cancer (CRPC), prostate cancer-specific survival (PCSS), and overall survival (OS) were estimated using the Kaplan-Meier method. Cox regression was used for comparative analyses. RESULTS: At a median of 6.1 years after second BCR, DM, CRPC, PCSS and OS rates were 41%, 27%, 83% and 73%, respectively. On multivariable analysis, interval to second BCR <1 year (hazard ratio [HR] 2.66, 95% confidence interval [CI] 1.71-4.14; P < 0.001], Gleason score 8-10 (HR 1.65, 95% CI 1.07-2.54; P = 0.022), and concurrent ADT during SRT (HR 1.76, 95% CI 1.08-2.88; P = 0.024) were associated with FFDM, while PCSS was associated with interval to second BCR <1 year (HR 3.00, 95% CI 1.69-5.32; P < 0.001) and concurrent ADT during SRT (HR 2.15, CI 1.13-4.08; P = 0.019). These risk factors were used to stratify patients into three groups, with 6-year FFDM rates of 71%, 59% and 33%, and PCSS rates of 89%, 79%, and 65%, respectively. CONCLUSION: Following second BCR after SRT, clinical progression is enriched in a subgroup of patients with prostate cancer, while others remain without DM for long intervals. Stratifying patients into risk groups using prognostic factors may aid counselling and future trial design.

Number of Unfavorable Intermediate-Risk Factors Predicts Pathologic Upstaging and Prostate Cancer-Specific Mortality Following Radical Prostatectomy: Results From the SEARCH Database.

BACKGROUND: To validate and further improve the stratification of intermediate risk prostate cancer into favorable and unfavorable subgroups for patients undergoing radical prostatectomy. MATERIALS AND METHODS: The SEARCH database was queried for IR patients undergoing radical prostatectomy without adjuvant radiotherapy. UIR disease was defined any patient with at least one unfavorable risk factor (URF), including primary Gleason pattern 4, 50% of more biopsy cores containing cancer, or multiple National Comprehensive Cancer Network IR factors. RESULTS: One thousand five hundred eighty-six patients with IR prostate cancer comprised the study cohort. Median follow-up was 62 months. Patients classified as UIR were significantly more likely to have pathologic high-risk features, such as Gleason score 8 - 10, pT3-4 disease, or lymph node metastases, than FIR patients (P < 0.001). Furthermore, UIR patients had significantly higher rates of PSA-relapse (PSA, hazard ratio [HR] = 1.89, P < 0.001) and distant metastasis (DM, HR = 2.92, P = 0.001), but no difference in prostate cancer-specific mortality (PCSM) or all-cause mortality in multivariable analysis. On secondary analysis, patients with ≥2 URF had significantly worse PSA-RFS, DM, and PCSM than those with 0 or 1 URF. Moreover, 40% of patients with ≥2 URF had high-risk pathologic features. CONCLUSIONS: Patients with UIR prostate cancer are at increased risk of PSA relapse, DM, and pathologic upstaging following prostatectomy. However, increased risk of PCSM was only detected in those with ≥2 URF. This suggests that further refinement of the UIR subgroup may improve risk stratification. Prostate Prostate 77:154-163, 2017. © 2016 Wiley Periodicals, Inc.

Modified risk stratification grouping using standard clinical and biopsy information for patients undergoing radical prostatectomy: Results from SEARCH.

INTRODUCTION: Prostate cancer is a heterogeneous disease, and risk stratification systems have been proposed to guide treatment decisions. However, significant heterogeneity remains for those with unfavorable-risk disease. METHODS: This study included 3335 patients undergoing radical prostatectomy without adjuvant radiotherapy in the SEARCH database. High-risk patients were dichotomized into standard and very high-risk (VHR) groups based on primary Gleason pattern, percentage of positive biopsy cores (PPBC), number of NCCN high-risk factors, and stage T3b-T4 disease. Similarly, intermediate-risk prostate cancer was separated into favorable and unfavorable groups based on primary Gleason pattern, PPBC, and number of NCCN intermediate-risk factors. RESULTS: Median follow-up was 78 months. Patients with VHR prostate cancer had significantly worse PSA relapse-free survival (PSA-RFS, P < 0.001), distant metastasis (DM, P = 0.004), and prostate cancer-specific mortality (PCSM, P = 0.015) in comparison to standard high-risk (SHR) patients in multivariable analyses. By contrast, there was no significant difference in PSA-RFS, DM, or PCSM between SHR and unfavorable intermediate-risk (UIR) patients. Therefore, we propose a novel risk stratification system: Group 1 (low-risk), Group 2 (favorable intermediate-risk), Group 3 (UIR and SHR), and Group 4 (VHR). The c-index of this new grouping was 0.683 for PSA-RFS and 0.800 for metastases, compared to NCCN-risk groups which yield 0.666 for PSA-RFS and 0.764 for metastases. CONCLUSIONS: Patients classified as VHR have markedly increased rates of PSA relapse, DM, and PCSM in comparison to SHR patients, whereas UIR and SHR patients have similar prognosis. Novel therapeutic strategies are needed for patients with VHR, likely involving multimodality therapy.

Treatment at high-volume facilities and academic centers is independently associated with improved survival in patients with locally advanced head and neck cancer.

BACKGROUND: The treatment of head and neck cancers is complex and associated with significant morbidity, requiring multidisciplinary care and physician expertise. Thus, facility characteristics, such as clinical volume and academic status, may influence outcomes. METHODS: The current study included 46,567 patients taken from the National Cancer Data Base who were diagnosed with locally advanced invasive squamous cell carcinomas of the oropharynx, larynx, and hypopharynx and were undergoing definitive radiotherapy. High-volume facilities (HVFs) were defined as the top 1% of centers by the number of patients treated from 2004 through 2012. Multivariable Cox regression and propensity score matching were performed to account for imbalances in covariates. RESULTS: The median follow-up was 55.1 months. Treatment at a HVF (hazard ratio, 0.798; 95% confidence interval, 0.753-0.845 [P<.001]) and treatment at an academic facility (hazard ratio, 0.897; 95% confidence interval, 0.871-0.923 [P<.001]) were found to be independently associated with improved overall survival in multivariable analysis. In propensity score-matched cohorts, the 5-year overall survival rate was 61.6% versus 55.5% for patients treated at an HVF versus lower-volume facilities, respectively (P<.001). Similarly, the 5-year overall survival rate was 52.3% versus 49.7% for patients treated at academic versus nonacademic facilities (P<.001). Analysis of facility volume as a continuous variable demonstrated continual improvement in survival with an increased number of patients treated. The impact of facility volume and academic designation on survival was observed when using a variety of thresholds to define HVF, and across the vast majority of subgroups, including both oropharyngeal and nonoropharyngeal subsites. CONCLUSIONS: Patients with locally advanced head and neck squamous cell carcinoma who are undergoing curative radiotherapy at HVFs and academic centers appear to have improved survival. Cancer 2017;123:3933-42. © 2017 American Cancer Society.

Combined high-intensity local treatment and systemic therapy in metastatic head and neck squamous cell carcinoma: An analysis of the National Cancer Data Base.

BACKGROUND: There is increasing evidence that primary tumor ablation can improve survival for some cancer patients with distant metastases. This may be particularly applicable to head and neck squamous cell carcinoma (HNSCC) because of its tropism for locoregional progression. METHODS: This study included patients with metastatic HNSCC undergoing systemic therapy identified in the National Cancer Data Base. High-intensity local treatment was defined as radiation doses ≥ 60 Gy or oncologic resection of the primary tumor. Multivariate Cox regression, propensity score matching, landmark analysis, and subgroup analysis were performed to account for imbalances in covariates, including adjustments for the number and location of metastatic sites in the subset of patients with this information available. RESULTS: In all, 3269 patients were included (median follow-up, 51.5 months). Patients undergoing systemic therapy with local treatment had improved survival in comparison with patients receiving systemic therapy alone in propensity score-matched cohorts (2-year overall survival, 34.2% vs 20.6%; P < .001). Improved survival was associated only with patients receiving high-intensity local treatment, whereas those receiving lower-intensity local treatment had survival similar to that of patients receiving systemic therapy without local treatment. The impact of high-intensity local therapy was time-dependent, with a stronger impact within the first 6 months after the diagnosis (adjusted hazard ratio [AHR], 0.255; 95% confidence interval [CI], 0.210-0.309; P < .001) in comparison with more than 6 months after the diagnosis (AHR, 0.622; 95% CI, 0.561-0.689; P < .001) in the multivariate analysis. A benefit was seen in all subgroups, in landmark analyses of 1-, 2-, and 3-year survivors, and when adjusting for the number and location of metastatic sites. CONCLUSIONS: Aggressive local treatment warrants prospective evaluation for select patients with metastatic HNSCC. Cancer 2017;123:4583-4593. © 2017 American Cancer Society.