A prospective clinical trial of proton therapy for chordoma and chondrosarcoma: Feasibility assessment.

BACKGROUND/OBJECTIVES: Proton therapy (PRT) has emerged as a treatment option for chordomas/chondrosarcomas to escalate radiation dose more safely. We report results of a phase I/II trial of PRT in patients with chordoma/chondrosarcoma. METHODS: Twenty adult patients with pathologically confirmed, nonmetastatic chordoma or chondrosarcoma were enrolled in a single-institution prospective trial of PRT from 2010 to 2014. Seventeen patients received adjuvant PRT and three received definitive PRT. Median dose was 73.8 Gy(RBE; range 68.4-79.2 Gy) using PRT-only (n = 6) or combination PRT/intensity-modulated radiotherapy (IMRT) (n = 14). Quality-of-life (QOL) and fatigue were assessed weekly and every 3 months posttreatment with the Functional Assessment of Cancer Therapy - Brain (FACTBr) and Brief Fatigue Inventory. Primary endpoint was feasibility (90% completing treatment with < 10 day treatment delay and ≤ 20% unexpected acute grade ≥ 3 toxicity). RESULTS: Tumors included chordomas of the skull base (n = 10), sacrum (n = 5), and cervical spine (n = 3), and skull base chondrosarcomas (n = 2). Median age was 57. The 80% had positive margins/gross disease. Median follow-up was 37 months. Feasibility endpoints were met. The 3-year local control and progression-free survival was 86% and 81%. There were no deaths. Two patients had acute grade 3 toxicity (both fatigue). One had late grade 3 toxicity (epistaxis and osteoradionecrosis). There were no significant differences in patient reported fatigue or QOL from baseline to the end-of-treatment. CONCLUSIONS: We report favorable local control, survival, and toxicity following PRT.

A Novel Mouse Model of Radiation-Induced Cardiac Injury Reveals Biological and Radiological Biomarkers of Cardiac Dysfunction with Potential Clinical Relevance.

PURPOSE: Radiation-induced cardiotoxicity is a significant concern in thoracic oncology patients. However, the basis for this disease pathology is not well characterized. We developed a novel mouse model of radiation-induced cardiotoxicity to investigate pathophysiologic mechanisms and identify clinically targetable biomarkers of cardiac injury. EXPERIMENTAL DESIGN: Single radiation doses of 20, 40, or 60 Gy were delivered to the cardiac apex of female C57BL/6 mice ages 9-11 weeks, with or without adjacent lung tissue, using conformal radiotherapy. Cardiac tissue was harvested up to 24 weeks post-radiotherapy for histologic analysis. Echocardiography and Technetium-99m sestamibi single photon emission computed tomography (SPECT) at 8 and 16 weeks post-radiotherapy were implemented to evaluate myocardial function and perfusion. Mouse cardiac tissue and mouse and human plasma were harvested for biochemical studies. RESULTS: Histopathologically, radiotherapy resulted in perivascular fibrosis 8 and 24 (P < 0.05) weeks post-radiotherapy. Apical perfusion deficits on SPECT and systolic and diastolic dysfunction on echocardiography 8 and 16 weeks post-radiotherapy were also observed (P < 0.05). Irradiated cardiac tissue and plasma showed significant increases in placental growth factor (PlGF), IL6, and TNFα compared with nonradiated matched controls, with greater increases in cardiac cytokine levels when radiotherapy involved lung. Human plasma showed increased PlGF (P = 0.021) and TNFα (P = 0.036) levels after thoracic radiotherapy. PlGF levels demonstrated a strong correlation (r = 0.89, P = 0.0001) with mean heart dose. CONCLUSIONS: We developed and characterized a pathophysiologically relevant mouse model of radiation-induced cardiotoxicity involving in situ irradiation of the cardiac apex. The model can be used to integrate radiomic and biochemical markers of cardiotoxicity to inform early therapeutic intervention and human translational studies.

Four-Year Outcomes From a Prospective Phase II Clinical Trial of Moderately Hypofractionated Proton Therapy for Localized Prostate Cancer.

PURPOSE: Moderately hypofractionated radiation therapy represents an effective treatment for localized prostate cancer (PC). Although large randomized trials have reported the efficacy of photon-based hypofractionated therapy, hypofractionated proton therapy (HFPT) has not been extensively studied. This study was performed to determine the clinical and patient-reported outcomes for patients with PC treated with HFPT. METHODS AND MATERIALS: Between 2010 and 2017, 184 men were enrolled on a trial of 70 Gy in 28 fractions of HFPT for low- to intermediate-risk PC. Acute and late toxicity was evaluated using National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Patient-reported outcomes were measured by International Prostate Symptom Score, International Index of Erectile Function Questionnaire, and Expanded Prostate Cancer Index Composite scores. RESULTS: Median follow-up was 49.2 months. Enrolled patients had low-risk (n = 18), favorable intermediate-risk (n = 78), and unfavorable intermediate-risk (n = 88) PC. Four-year rates of biochemical-clinical failure-free survival were 93.5% (95% confidence interval, 89%-98%), 94.4% (89%-100%), 92.5% (86%-100%), and 93.8% (88%-100%) in the overall group and the low-risk, favorable intermediate-risk, and unfavorable intermediate-risk cohorts, respectively (log-rank P > .4). The incidence of acute grade 2 or higher gastrointestinal (GI) and urologic toxicities were 3.8% and 12.5%, respectively. The 4-year incidence of late grade 2 or higher urologic and GI toxicity was 7.6% (4%-13%) and 13.6% (9%-20%), respectively. One late grade 3 GI toxicity was reported. All late toxicities were transient. Patient-reported International Prostate Symptom, International Index of Erectile Function, and Expanded Prostate Cancer Index Composite scores had no significant long-term changes after completion of HFPT (Supplementary Table 1, available at https://doi.org/10.1016/j.ijrobp.2019.05.069). CONCLUSIONS: HFPT is associated with low rates of toxicity and does not appear to negatively affect 4-year patient reported urinary and bowel health. Further comparative analyses are warranted to better understand differences between proton and photon HFRT.

Predictors of preferences and utilities in men treated with 3D-CRT for prostate cancer.

PURPOSE: To assess the preferences and utilities for prostate cancer health state scenarios of men treated with three-dimensional conformal radiotherapy and the predictors of treatment preferences. METHODS AND MATERIALS: The preferences and utilities for probabilistic health states of impotence and incontinence associated with prostate cancer therapies were elicited from prostate cancer registry participants using a modified time trade-off interview. Sociodemographic, disease, and treatment characteristics, as well as quality-of-life scores, were assessed to determine the predictors of preferences. RESULTS: Fifty-seven men treated with three-dimensional conformal radiotherapy completed the time trade-off interview. Of these men, 83% had Stage T1-T2 and 30% were receiving hormonal therapy. The utilities followed a linear trend with declining scores for increasing risk of poorer health states. Men showed an increased preference for health states associated with radiotherapy compared with surgery or hormonal therapy. Univariate predictors of preference included income and marital status. Multivariate predictors of preferences included more aggressive therapy and better prognostic indicators. Current quality-of-life scores in terms of global, sexual, or urinary function were poor predictors of preferences. CONCLUSION: Preference elicitation can assist in decision-making, and understanding the predictors of patient preferences can assist in identifying factors that may increase patient perceptions of poorer outcomes.

How to establish a high-risk cancer genetics clinic: limitations and successes.

The development of technology to locate and isolate cancer susceptibility genes has brought together the fields of oncology, cancer control, genetics, and genetic counseling to create a new specialty of cancer risk counseling with the goal to communicate more accurate information about personal cancer risk profiles based on personal and family histories. As cancer risk assessment and counseling services become standard of care in medical practice, their availability is increasingly moving from comprehensive cancer centers and academic institutions to community settings. High-risk cancer genetics clinics in the community face several challenges, including staffing, time commitment, costs, and unique quality control issues. The societal benefits include a more educated public armed with the information needed to make health decisions appropriate for the individual level of risk.

Free prostate-specific antigen improves prostate cancer detection in a high-risk population of men with a normal total PSA and digitalrectal examination.

OBJECTIVES: Uncertainty exists regarding optimal prostate cancer screening parameters for high-risk populations. The purpose of this study is to report the use of percent free prostate-specific antigen (PSA) as an indication for biopsy in men at increased risk for developing prostate cancer who have a normal digital rectal examination (DRE) and total PSA level between 2 and 4 ng/mL. METHODS: African-American men and men with at least one first-degree relative with prostate cancer are eligible for enrollment into the Prostate Cancer Risk Assessment Program (PRAP) at our institution. Between October 1996 and April 2002, 310 asymptomatic high-risk men with no history of prostate cancer, benign prostatic hyperplasia (BPH), or prostatic intraepithelial neoplasia (PIN) were screened in the PRAP with DRE and total PSA. Percent free PSA was obtained in men with a total PSA between 2 and 10 ng/mL. Men with a normal DRE and total PSA between 2 and 4 ng/mL were advised to undergo transrectal ultrasound-guided (TRUS) biopsies of the prostate if the percent free PSA was less than 27%. Other indications for biopsy included an abnormal DRE or a total PSA greater than 4 ng/mL. The primary endpoint evaluated was prostate cancer detection in high-risk men with a benign prostate examination, a normal total PSA between 2 and 4 ng/mL, and percent free PSA less than 27%. RESULTS: Of the 310 men, 174 (56%) were African American and 202 (65%) had at least one first-degree relative with prostate cancer. Sixty-two of the 310 men were referred for prostate biopsy, and 40 of 62 had biopsy performed. Twenty-one of 40 men were diagnosed with prostate cancer for a cancer detection rate of 53% in all men undergoing biopsy and an overall cancer detection rate of 6.8% in this high-risk population. Thirty-seven high-risk men (median age 54 years) with a total PSA level between 2 and 4 ng/mL (median 2.7 ng/mL) and a normal DRE were found to have a percent free PSA level of less than 27% (median 16%, range 8% to 25%). Twenty-three of these 37 men (62%) proceeded with the recommended prostate biopsy. Prostatic adenocarcinoma was diagnosed in 12 of 23 men for a cancer detection rate of 52% in men undergoing biopsy and 32% in all men with a normal DRE, a total PSA between 2 and 4 ng/mL, and a percent free PSA less than 27%. All positive biopsies demonstrated clinically significant Gleason score 6 or 7 disease. In all men electing radical prostatectomy, bilateral organ-confined disease (pT2bN0M0) was confirmed. CONCLUSIONS: In this unique population of men at high risk for prostate cancer, a percent free PSA of less than 27% was found to be useful for detecting early-stage but clinically significant cancers in men with a total PSA value between 2 and 4 ng/mL and normal DRE findings.