Health Disparities in Prostate Cancer and Approaches to Advance Equitable Care

The American Cancer Society estimates approximately 268,490 new cases of prostate cancer and approximately 34,500 deaths caused by prostate cancer in the United States for 2022. Globally, a total of 1,414,259 new cases of prostate cancer and 375,304 related deaths were reported in 2020. Well-documented health disparities and inequities exist along the continuum of care for prostate cancer management-from screening to diagnostic and staging work-up, surveillance, and treatment-ultimately impacting clinical outcomes. This session-based article discusses innovative patient-centered approaches to advance equitable prostate cancer care. It begins with a review of domestic health disparities in diagnostic imaging and radiotherapy for prostate cancer, and it summarizes barriers and solutions to achieving health equity, such as equity metrics and practice quality improvement projects. Next, a global perspective is provided that describes approaches to address financial and geographic barriers to prostate cancer care, including specific examples of strategies that emphasize the use of the cheapest method of care delivery while maintaining outcomes for drug delivery and radiotherapy.

Phase II, double-blind, randomized study of salvage radiation therapy (SRT) plus enzalutamide or placebo for high-risk PSA-recurrent prostate cancer after radical prostatectomy: The SALV-ENZA Trial

5012

Background: We sought to investigate whether enzalutamide (ENZA) treatment, without androgen deprivation therapy, increases freedom-from-PSA-progression (FFPP) when combined with salvage radiation therapy (SRT) in men with recurrent prostate cancer post-radical prostatectomy (RP). Methods: Men with biochemically recurrent prostate cancer after RP were enrolled into a randomized, double-blind, phase II, placebo-controlled, multicenter study of SRT + placebo vs SRT + ENZA. The randomization (1:1) was stratified by center, surgical margin status (R0 vs R1), PSA prior to salvage treatment (PSA ≥0.5 vs < 0.5 ng/mL), and pathologic Gleason sum (7 vs 8-10) using a minimization algorithm. Following randomization, patients received either placebo or ENZA 160 mg PO once daily for 6 months. Following 2 months of study drug therapy, external beam radiotherapy to 66.6-70.2 Gy was administered to the prostate bed (no pelvic nodes). The primary endpoint was FFPP. The trial design was powered for a HR 0.44 FFPP benefit with intended enrollment of 96 subjects and was closed as planned to enrollment on March 2020 short of that goal. Secondary endpoints were time to local recurrence (LR) within the radiation field, metastasis‐free survival (MFS), and safety as determined by frequency and severity of adverse events (AEs). Results: A total of 86 patients were randomized with a median follow-up of 34 (range 0-52) months. The median pre-SRT PSA was 0.3 (range 0.06-4.6) ng/mL, 56/86 (65%) had extra-prostatic disease (pT3), 39/86 (45%) had Gleason Grade Group 4 or higher and 43/96 (50%) had positive surgical margins. Trial arms were well balanced. FFPP was significantly improved with ENZA vs placebo, for example 2-year FFPP was 87.1% vs 68.1%, respectively, and overall with a HR 0.40 [95% confidence interval (CI), 0.17-0.92, p-value = 0.026]. Subgroup analyses demonstrate differential benefit (p-value of interaction = 0.031) of ENZA in men with pT3 (HR 0.19, 95%CI 0.05-0.67) vs pT2 disease (HR 1.29, 95%CI 0.34-4.81). There were insufficient secondary endpoint events for analysis. The most common adverse events were grade 1-2 fatigue (13% ENZA vs 9%) and urinary frequency (6 % ENZA vs 8%). Conclusions: SRT plus ENZA monotherapy for men with PSA recurrent high-risk prostate cancer following RP is safe and delays PSA progression relative to SRT alone. The impact of ENZA on distant metastasis or survival is unknown at this time. Additional molecular biomarker analyses are being pursued. Clinical trial information: NCT02203695.

Interim analysis of companion, prospective, phase II, clinical trials assessing the efficacy and safety of multi-modal total eradication therapy in men with synchronous oligometastatic prostate cancer

Multimodal therapies were combined to eradicate the primary site, metastatic, and micrometastatic disease in men with newly diagnosed, synchronous, oligometastatic prostate cancer. The investigation included companion, phase II studies: total eradication therapy-1 (TET-1) for those treatment-naïve and total eradication therapy-2 (TET-2) for those post-prostatectomy. The treatment-naive protocol included androgen deprivation and docetaxel (with concurrent abiraterone added in a protocol amendment), followed by a prostatectomy, adjuvant radiation (if positive margins, T3/4, or detectable PSA), and metastasis-directed therapy. The post-prostatectomy protocol assigned the same therapies (omitting the prostatectomy). The primary endpoint was an undetectable PSA with recovered testosterone. The safety boundaries were ≤ 50% for grade 3/4 neutropenic and ≤ 20% for grade 3/4 surgical- and radiation-related toxicities. Enrollment was planned for 60 patients per protocol, to detect a PSA progression-free survival ≥ 32%, as compared to 15% in a historic control. Enrollment closed early. An interim analysis was conducted once > 50% of patients were evaluable for the primary endpoint. The primary endpoint duration was assessed by median progression-free survival. 52 patients were enrolled (n = 26 per protocol). Medium follow-up was 30.3 months. 80% (24/30) of evaluable patients achieved the primary endpoint; the duration was not reached. Of those not evaluable, 77% (17/22) had not reached the endpoint and 23% (5/22) had exited. There were 8% (4/52) grade 3/4 neutropenic and 2% (1/48) grade 3/4 surgical or radiation-induced toxicities. Interim findings suggest the trials' endpoints were met, advancing the concept of total eradication therapy in men with oligometastatic prostate cancer.

Evaluating Proton Dose and Associated Range Uncertainty Using Daily Cone-Beam CT

Purpose

This study aimed to quantitatively evaluate the range uncertainties that arise from daily cone-beam CT (CBCT) images for proton dose calculation compared to CT using a measurement-based technique.

Methods

For head and thorax phantoms, wedge-shaped intensity-modulated proton therapy (IMPT) treatment plans were created such that the gradient of the wedge intersected and was measured with a 2D ion chamber array. The measured 2D dose distributions were compared with 2D dose planes extracted from the dose distributions using the IMPT plan calculated on CT and CBCT. Treatment plans of a thymoma cancer patient treated with breath-hold (BH) IMPT were recalculated on 28 CBCTs and 9 CTs, and the resulting dose distributions were compared.

Results

The range uncertainties for the head phantom were determined to be 1.2% with CBCT, compared to 0.5% for CT, whereas the range uncertainties for the thorax phantom were 2.1% with CBCT, compared to 0.8% for CT. The doses calculated on CBCT and CT were similar with similar anatomy changes. For the thymoma patient, the primary source of anatomy change was the BH uncertainty, which could be up to 8 mm in the superior-inferior (SI) direction.

Conclusion

We developed a measurement-based range uncertainty evaluation method with high sensitivity and used it to validate the accuracy of CBCT-based range and dose calculation. Our study demonstrated that the CBCT-based dose calculation could be used for daily dose validation in selected proton patients.

Radiating the prostate bed in relapsed oligometastatic prostate cancer: How comprehensive should we be?

PURPOSE

A subset of patients with high-risk pathological features at radical prostatectomy recur with oligometastatic disease. The aim of this study is to investigate the rate of prostate bed recurrence, with or without history of prostate bed irradiation (PBRT), in oligometastatic prostate cancer (OMPC) patients after metastasis-directed therapy (MDT).

METHODS

We performed a retrospective analysis of hormone-sensitive OMPC patients treated initially with curative-intent radical prostatectomy followed by disease recurrence and metastasis-directed stereotactic ablative radiotherapy (SABR) at our institution. Prostate bed recurrence rates were compared between patients who had PBRT at any point (i.e., before oligometastatic diagnosis or concurrently with MDT) versus those with no history of PBRT.

RESULTS

Seventy-seven patients were included, and 68.8% had received PBRT. There were no significant differences in baseline characteristics between those who had received and had not received PBRT. There were five prostate bed recurrences following MDT, specifically with a 24-month cumulative incidence of 30.4% in patients who did not have PBRT and 2.4% in those who did (p = 0.03). Three of the five recurrences were isolated to the prostate bed at time of recurrence.

CONCLUSIONS

Relapsed oligometastatic prostate cancer patients who have not received maximal local consolidative therapy to the prostate bed may have higher rates of local failure. Prospective studies are warranted investigating when prostate bed irradiation should be considered for patients after radical prostatectomy who ultimately have oligometastatic prostate cancer.

Demographics of ASTRO Student Members and Potential Implications for Future U.S. Radiation Oncology Workforce Diversity

Purpose

The radiation oncology workforce in the United States is comparatively less diverse than the U.S. population and U.S. medical school graduates. Workforce diversity correlates with higher quality care and outcomes. The purpose of this study was to determine whether student members of the American Society for Radiation Oncology (ASTRO) are any more diverse than resident members-in-training using the recently established medical student membership category.

Methods and Materials

Self-reported sex, race and Hispanic ethnicity, medical school, and degree(s) earned for all medical students (n = 268) and members-in-training (n = 713) were collected from the ASTRO membership database. International members were excluded. The χ² test was used to assess for differences between subgroups.

Results

Compared with members-in-training, student members were more likely to be female (40.0% vs 31.5%, P = .032), black or African American (10.7% vs 4.8%, P = .009), candidates for or holders of a DO rather than MD degree (5.2% vs 1.5%, P = .002), and from a U.S. medical school that is not affiliated with a radiation oncology residency program (30.5% vs 20.9%, P = .001). There was no significant difference in self-reported Hispanic ethnicity (7.3% vs 5.4%, P = .356). There were no indigenous members in either category assessed.

Conclusions

Medical student members of ASTRO are more diverse in terms of black race, female sex, and osteopathic training, though not in terms of Hispanic ethnicity or nonmultiracial indigenous background, than the members-in-training. Longitudinal engagement with these students and assessment of the factors leading to specialty retention versus attrition may increase diversity, equity, and inclusion in radiation oncology.

Establishing a Deaf and American Sign Language Inclusive Residency Program

Improving diversity in residency programs has been increasingly emphasized as a means to address gender, racial, and ethnic disparities in medicine. However, limited attention has been given to the potential benefits of training physicians with differences other than gender or race and ethnicity. Americans with a disability represent about 27% of the U.S. population, whereas 1%-3% of physician trainees report having a disability. In 2013, a national survey identified only 86 physicians or trainees reporting deafness or hearing loss as a disability. To date, there are no published strategies on how to create an inclusive program for Deaf trainees. Herein, the authors report on the development of a Deaf and American Sign Language (ASL) inclusive residency program that can serve as an academic model for other programs, in any medical specialty, seeking to create an accessible training program for Deaf physicians and that can be adapted for trainees with other disabilities. In March 2017, the radiation oncology residency program at Johns Hopkins University matched an ASL-signing Deaf resident who would begin the program in July 2018. In preparation, department leadership engaged key stakeholders and leaders within the university's health system and among the department faculty, residents, and staff as well as the incoming resident to create an ASL inclusive program. A 5-step transition process for the training program was ultimately developed and implemented. The authors focused on engaging the Deaf trainee and interpreters, engaging health system and departmental leadership, contracting a training consultant and developing oral and written training materials for faculty and staff, and optimizing the workspace via accommodations. Through collaborative preparation, a Deaf and ASL-signing resident was successfully integrated into the residency program. The proposed 5-step transition process provides an effective, engaging model to encourage other institutions that are seeking to employ similar inclusivity initiatives.

Interplay Between Duration of Androgen Deprivation Therapy and External Beam Radiotherapy With or Without a Brachytherapy Boost for Optimal Treatment of High-risk Prostate Cancer: A Patient-Level Data Analysis of 3 Cohorts

IMPORTANCE

Radiotherapy combined with androgen deprivation therapy (ADT) is a standard of care for high-risk prostate cancer. However, the interplay between radiotherapy dose and the required minimum duration of ADT is uncertain.

OBJECTIVE

To determine the specific ADT duration threshold that provides a distant metastasis-free survival (DMFS) benefit in patients with high-risk prostate cancer receiving external beam radiotherapy (EBRT) or EBRT with a brachytherapy boost (EBRT+BT).

DESIGN, SETTINGS, AND PARTICIPANTS

This was a cohort study of 3 cohorts assembled from a multicenter retrospective study (2000-2013); a post hoc analysis of the Randomized Androgen Deprivation and Radiotherapy 03/04 (RADAR; 2003-2007) randomized clinical trial (RCT); and a cross-trial comparison of the RADAR vs the Deprivación Androgénica y Radio Terapía (Androgen Deprivation and Radiation Therapy; DART) 01/05 RCT (2005-2010). In all, the study analyzed 1827 patients treated with EBRT and 1108 patients treated with EBRT+BT from the retrospective cohort; 181 treated with EBRT and 203 with EBRT+BT from RADAR; and 91 patients treated with EBRT from DART. The study was conducted from October 15, 2020, to July 1, 2021, and the data analyses, from January 5 to June 15, 2021.

EXPOSURES

High-dose EBRT or EBRT+BT for an ADT duration determined by patient-physician choice (retrospective) or by randomization (RCTs).

MAIN OUTCOMES AND MEASURES

The primary outcome was DMFS; secondary outcome was overall survival (OS). Natural cubic spline analysis identified minimum thresholds (months).

RESULTS

This cohort study of 3 studies totaling 3410 men (mean age [SD], 68 [62-74] years; race and ethnicity not collected) with high-risk prostate cancer found a significant interaction between the treatment type (EBRT vs EBRT+BT) and ADT duration (binned to <6, 6 to <18, and ≥18 months). Natural cubic spline analysis identified minimum duration thresholds of 26.3 months (95% CI, 25.4-36.0 months) for EBRT and 12 months (95% CI, 4.9-36.0 months) for EBRT+BT for optimal effect on DMFS. In RADAR, the prolongation of ADT for patients receiving only EBRT was not associated with significant improvements in DMFS (hazard ratio [HR], 1.01; 95% CI, 0.65-1.57); however, for patients receiving EBRT+BT, a longer duration was associated with improved DMFS (DMFS HR, 0.56; 95% CI, 0.36-0.87; P = .01). For patients receiving EBRT alone (DART), 28 months of ADT was associated with improved DMFS compared with 18 months (RADAR HR, 0.37; 95% CI, 0.17-0.80; P = .01).

CONCLUSIONS AND RELEVANCE

These cohort study findings suggest that the optimal minimum ADT duration for treatment with high-dose EBRT alone is more than 18 months; and for EBRT+BT, it is 18 months or possibly less. Additional studies are needed to determine more precise minimum durations.

Early initiation of salvage radiotherapy is associated with improved metastasis-free survival in patients with relapsed prostate cancer following prostatectomy

262

Background: Salvage radiation therapy is a recognized management option for patients who develop biochemical failure following radical prostatectomy. However, given the documented long natural history of biochemically relapsed prostate cancer after prostatectomy, questions remain on the value of early salvage intervention vs initial expectant management, especially with regards to more critical clinical rather than biochemical endpoints. We sought to determine the impact of early salvage radiotherapy (initiated at PSA 0.2 - 0.5 ng/ml) on metastasis-free survival in patients who receive salvage radiotherapy following prostatectomy for clinically localized prostate cancer. Methods: Using tumor registry data, we identified 408 patients who received salvage radiation therapy between 1986 – 2016 at our institution. We analyzed association between survival outcomes and prognostic factors, including pre-treatment and nadir prostate-specific antigen (PSA), interval between prostatectomy and initiation of salvage RT, use of neoadjuvant/concurrent hormonal suppression, and adverse pathologic features, including Gleason score, extraprostatic extension, seminal vesicle invasion, nodal involvement, and margin status. Univariate analyses and multivariable-adjusted Cox proportional hazards models were constructed to assess association between these clinical and pathologic features and duration of biochemical relapse-free survival (bRFS) and metastasis-free survival (MFS). Construction of Kaplan-Meier survival curves stratifies survival by predictive features. Results: Overall, 187 (45.8%) patients received salvage radiotherapy while PSA levels were 0.2 - 0.5 ng/ml (early salvage). One hundred thirty three (32.6%) patients received neoadjuvant/concurrent androgen deprivation therapy (ADT). Median radiation dose was 68.4 Gy and did not differ significantly between treatment subgroups. Independent of pathologic features and use of ADT, early-salvage at lower PSA levels was the most significant predictor of improved bRFS and MFS, HR = 0.52 (95% CI [0.35, 0.79], p = 0.002), and HR = 0.58 (95% CI [0.37, 0.91], p = 0.02), respectively. Seminal vesicle invasion was associated with shorter interval to biochemical failure (HR = 1.79 (95% CI [1.07, 2.98], p = 0.03), but not significant difference in MFS. Conversely, nodal involvement was a significant predictor of worse MFS, with HR = 2.18 (95% CI [1.04, 4.57], p = 0.04). Notably, interval between prostatectomy and initiation of salvage radiation was not a significant prognostic factor for bRFS or MFS. Conclusions: Independent of pathologic features and use of ADT, the initiation of salvage radiation therapy early after biochemical relapse (PSA ≤ 0.5 ng/ml) following prostatectomy is associated with increased metastasis-free as well as biochemical relapse-free survival.

A Survey to Assess and Delineate Approaches to Medical Student Outreach to Promote Diversity at Academic Radiation Oncology Programs

PURPOSE/OBJECTIVE(S)

To assess how academic radiation oncology departments engage medical students who are either female and/or from racial and ethnic demographic groups that are underrepresented in medicine (URiM).

MATERIALS/METHODS

An electronic survey was sent to all 83 radiation oncology residency program directors (or if applicable medical student directors) whose department is affiliated with an on-site medical school. Questions assessed whether any faculty in the participants' department offer exposure in radiation oncology specifically to medical and premedical student groups whose members are typically female or URiM, or promote the American Society for Radiation Oncology (ASTRO) Minority Summer Fellowship (MSF) Award. Barriers to these types of involvement were also assessed.

RESULTS

A representative from 54/83 programs responded (response rate 65%). Faculty from 83% of departments had given a presentation to an oncology or radiation oncology medical student interest group. However, faculty from only 18% of departments had given a presentation to a Student National Medical Association chapter, 9% to a Latino Medical Student Association chapter, and 11% to an American Medical Women's Association chapter. Faculty from 15% of departments actively promote the MSF to the general student body, and 24% promote it to any minority students who express interest in radiation oncology. Faculty from 22% of departments had given a presentation to a premedical student group, 10% to an undergraduate student group focused on minority or female students, and 20% to a pipeline program for high school (or younger) female or URiM students. Lack of awareness of the existence of such programs, or not being invited, were the most common barriers to participation.

CONCLUSIONS

Most academic radiation oncology departments do not offer educational outreach specifically targeting women or minority students or promote the MSF. Further efforts are needed to break from the status quo and attract a more diverse workforce.

Diversity Trends by Sex and Underrepresented in Medicine Status Among US Radiation and Medical Oncology Faculty Over 5 Decades

Importance

It remains unclear how the historical exclusion of women and racial and ethnic minority groups from medical training, and therefore the oncologic subspecialties, has contributed to rates of faculty diversity among oncology departments over time. Oncologic faculty diversity is an important initiative to help improve care and address health disparities for an increasingly diverse US population with cancer.

Objectives

To report trends in academic faculty representation by sex and by race and ethnicity for radiation oncology (RO) and medical oncology (MO) departments and to describe comparisons with the general US population, medical students, RO and MO trainees, clinical department chairs, and faculty in other departments.

Design, Setting, and Participants

This cross-sectional analysis used data from the Association of American Medical Colleges to analyze trends by sex and by race and ethnicity among full-time US faculty in RO and MO departments from 1970 through 2019. Data were analyzed between October 2020 and April 2021.

Main Outcomes and Measures

Proportions of women and individuals from underrepresented in medicine (URM) racial and ethnic groups (Black, Hispanic, and Indigenous individuals) were calculated among RO and MO academic departments; trends were analyzed over 5 decades. These proportions were compared with cohorts already described. In addition, proportions of women and URM individuals were calculated by faculty rank among RO and MO departments.

Results

In 1970, there were 119 total faculty in RO (10 women [8.4%] and 2 URM [1.7%]) and 87 total faculty in MO (11 women [12.6%] and 7 URM [8.0%]). In 2019, there were 2115 total faculty in RO (615 women [29.1%] and 108 URM [5.1%]) and 819 total faculty in MO (312 women [38.1%] and 47 URM [5.7%]). Total faculty numbers increased over time in both RO and MO. Faculty representation of URM women proportionally increased by 0.1% per decade in both RO (95% CI, 0.005%-0.110%; P <. 001 for trend) and MO (95% CI, -0.03% to 0.16%; P = .06 for trend) compared with non-URM women faculty, which increased by 0.4% (95% CI, 0.25%-0.80%) per decade in RO and 0.7% (95% CI, 0.47%-0.87%) per decade in MO (P < .001 for trend for both). Faculty representation of URM men did not significantly change for RO (0.03% per decade [95% CI, -0.008% to 0.065%]; P = .09 for trend) or MO (0.003% per decade [95% CI, -0.13% to 0.14%]; P = .94 for trend). Representation of both women and URM individuals among both specialties was lower than their representation in the US population in both 2009 and 2019. Across all cohorts studied, RO faculty had the lowest URM representation in 2019 at 5.1%. At every rank in 2019, the number of total URM faculty represented among both MO and RO remained low (MO: instructor, 2 of 44 [5%]; assistant professor, 18 of 274 [7%]; associate professor, 13 of 177 [7%]; full professor, 13 of 276 [5%]; and RO: instructor, 9 of 147 [6%]; assistant professor, 57 of 927 [6%]; associate professor, 20 of 510 [4%]; full professor, 18 of 452 [4%]).

Conclusions and Relevance

This cross-sectional study suggests that RO and MO academic faculty have increased the representation of women over time, while URM representation has lagged. The URM trends over time need further investigation to inform strategies to improve URM representation in RO and MO.

Performance of a Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography-Derived Risk-Stratification Tool for High-risk and Very High-risk Prostate Cancer

IMPORTANCE

Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) can detect low-volume, nonlocalized (ie, regional or metastatic) prostate cancer that was occult on conventional imaging. However, the long-term clinical implications of PSMA PET/CT upstaging remain unclear.

OBJECTIVES

To evaluate the prognostic significance of a nomogram that models an individual's risk of nonlocalized upstaging on PSMA PET/CT and to compare its performance with existing risk-stratification tools.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included patients diagnosed with high-risk or very high-risk prostate cancer (ie, prostate-specific antigen [PSA] level >20 ng/mL, Gleason score 8-10, and/or clinical stage T3-T4, without evidence of nodal or metastatic disease by conventional workup) from April 1995 to August 2018. This multinational study was conducted at 15 centers. Data were analyzed from December 2020 to March 2021.

EXPOSURES

Curative-intent radical prostatectomy (RP), external beam radiotherapy (EBRT), or EBRT plus brachytherapy (BT), with or without androgen deprivation therapy.

MAIN OUTCOMES AND MEASURES

PSMA upstage probability was calculated from a nomogram using the biopsy Gleason score, percentage positive systematic biopsy cores, clinical T category, and PSA level. Biochemical recurrence (BCR), distant metastasis (DM), prostate cancer-specific mortality (PCSM), and overall survival (OS) were analyzed using Fine-Gray and Cox regressions. Model performance was quantified with the concordance (C) index.

RESULTS

Of 5275 patients, the median (IQR) age was 66 (60-72) years; 2883 (55%) were treated with RP, 1669 (32%) with EBRT, and 723 (14%) with EBRT plus BT; median (IQR) PSA level was 10.5 (5.9-23.2) ng/mL; 3987 (76%) had Gleason grade 8 to 10 disease; and 750 (14%) had stage T3 to T4 disease. Median (IQR) follow-up was 5.1 (3.1-7.9) years; 1221 (23%) were followed up for at least 8 years. Overall, 1895 (36%) had BCR, 851 (16%) developed DM, and 242 (5%) died of prostate cancer. PSMA upstage probability was significantly prognostic of all clinical end points, with 8-year C indices of 0.63 (95% CI, 0.61-0.65) for BCR, 0.69 (95% CI, 0.66-0.71) for DM, 0.71 (95% CI, 0.67-0.75) for PCSM, and 0.60 (95% CI, 0.57-0.62) for PCSM (P < .001). The PSMA nomogram outperformed existing risk-stratification tools, except for similar performance to Staging Collaboration for Cancer of the Prostate (STAR-CAP) for PCSM (eg, DM: PSMA, 0.69 [95% CI, 0.66-0.71] vs STAR-CAP, 0.65 [95% CI, 0.62-0.68]; P < .001; Memorial Sloan Kettering Cancer Center nomogram, 0.57 [95% CI, 0.54-0.60]; P < .001; Cancer of the Prostate Risk Assessment groups, 0.53 [95% CI, 0.51-0.56]; P < .001). Results were validated in secondary cohorts from the Surveillance, Epidemiology, and End Results database and the National Cancer Database.

CONCLUSIONS AND RELEVANCE

These findings suggest that PSMA upstage probability is associated with long-term, clinically meaningful end points. Furthermore, PSMA upstaging had superior risk discrimination compared with existing tools. Formerly occult, PSMA PET/CT-detectable nonlocalized disease may be the main driver of outcomes in high-risk patients.

Overcoming Barriers to Radiation Oncology Access in Low-Resource Settings in the United States

Providing high-quality radiation therapy in medically underserved, low-resource environments can be challenging in the United States. During the American Society of Radiation Oncology 2020 Annual Meeting, the American Society for Radiation Oncology Committee on Health Equity, Diversity, and Inclusion hosted 4 radiation oncologists from both academic and community practices in an educational session. Speakers discussed creative ways to overcome barriers to equitable cancer care and outcomes for their vulnerable patient populations in both rural and urban settings. Successful tactics have included applying for state-sponsored grants, lobbying hospital leadership for equipment upgrades, implementing quality improvement programs specifically targeting the needs of the patient population, studying novel hypofractionation schedules, monitoring toxicities using wearable devices, and expanding transportation options.

Long-term Clinical Outcomes in Favorable Risk Prostate Cancer Patients Receiving Proton Beam Therapy

Purpose

Long-term data regarding the disease control outcomes of proton beam therapy (PBT) for patients with favorable risk intact prostate cancer (PC) are limited. Herein, we report our institution's long-term disease control outcomes in PC patients with clinically localized disease who received PBT as primary treatment.

Methods

One hundred sixty-six favorable risk PC patients who received definitive PBT to the prostate gland at our institution from 2010 to 2012 were retrospectively assessed. The outcomes studied were biochemical failure-free survival (BFFS), biochemical failure, local failure, regional failure, distant failure, PC-specific survival, and overall survival. Patterns of failure were also analyzed. Multivariate Cox proportional hazards modeling was used to estimate independent predictors of BFFS.

Results

The median length of follow-up was 8.3 years (range, 1.2–10.5 years). The majority of patients had low-risk disease (58%, n = 96), with a median age of 64 years at the onset of treatment. Of 166 treated men, 13 (7.8%), 8 (4.8%), 2 (1.2%) patient(s) experienced biochemical failure, local failure, regional failure, respectively. Regional failure was seen in an obturator lymph node in 1 patient and the external iliac lymph nodes in the other. None of the patients experienced distant failure. There were 5 (3.0%) deaths, none of which were due to PC. The 5- and 8-year BFFS rate were 97% and 92%, respectively. None of the clinical disease characteristics or treatment-related factors assessed were associated with BFFS on multivariate Cox proportional hazards modeling (all P > .05).

Conclusion

Disease control rates reported in our assessment of PBT were similar to those reported in previous clinically localized intact PC analyses, which used intensity-modulated radiotherapy, three-dimensional conformal radiotherapy, or radical prostatectomy as definitive therapy. In addition, BFFS rates were similar, if not improved, to previous PBT studies.