S. Suy

Acute Urinary Morbidity Following Stereotactic Body Radiation Therapy for Prostate Cancer with Prophylactic Alpha-Adrenergic Antagonist and Urethral Dose Reduction

Background Stereotactic body radiation therapy (SBRT) delivers high doses of radiation to the prostate while minimizing radiation to the adjacent critical organs. Large fraction sizes may increase urinary morbidity due to unavoidable treatment of the prostatic urethra. This study reports rates of acute urinary morbidity following SBRT for localized prostate cancer with prophylactic alpha-adrenergic antagonist utilization and urethral dose reduction (UDR). Methods From April 2013 to September 2014, 102 patients with clinically localized prostate cancer were treated with robotic SBRT to a total dose of 35–36.25u2009Gy in five fractions. UDR was employed to limit the maximum point dose of the prostatic urethra to 40u2009Gy. Prophylactic alpha-adrenergic antagonists were initiated 5u2009days prior to SBRT and continued until resolution of urinary symptoms. Quality of life (QoL) was assessed before and after treatment using the American Urological Association Symptom Score (AUA) and the Expanded Prostate Cancer Index Composite-26 (EPIC-26). Clinical significance was assessed using a minimally important difference (MID) of one half SD change from baseline. Results One hundred two patients underwent definitive prostate SBRT with UDR and were followed for 3u2009months. No patient experienced acute urinary retention requiring catheterization. A mean baseline AUA symptom score of 9.06 significantly increased to 11.83 1-week post-SBRT (pu2009=u20090.0024) and 11.84 1-month post-SBRT (pu2009=u20090.0023) but returned to baseline by 3u2009months. A mean baseline EPIC-26 irritative/obstructive score of 87.7 decreased to 74.1 1-week post-SBRT (pu2009<u20090.0001) and 77.8 1-month post-SBRT (pu2009<u20090.0001) but returned to baseline at 3u2009months. EPIC-26 irritative/obstructive score changes were clinically significant, exceeding the MID of 6.0. At baseline, 8.9% of men described their urinary function as a moderate to big problem, and that proportion increased to 37.6% 1u2009week following completion of SBRT before returning to baseline by 3u2009months. Conclusion Stereotactic body radiation therapy for localized prostate cancer with utilization of prophylactic alpha-adrenergic antagonist and UDR was well tolerated as determined by acute urinary function and bother, and symptoms were comparable to those observed following conventionally fractionated external beam radiation therapy (EBRT). Longer follow-up is required to assess long-term toxicity and efficacy following SBRT with UDR.

Utilization of Patient-Reported Outcomes to Guide Symptom Management During Stereotactic Body Radiation Therapy for Clinically Localized Prostate Cancer

Introduction Utilization of patient-reported outcomes (PROs) to guide symptom management during radiation therapy is increasing. This study focuses on the use of the Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP) as a tool to assess urinary and bowel bother during stereotactic body radiation therapy (SBRT) and its utility in guiding medical management. Methods Between September 2015 and January 2017, 107 patients with clinically localized prostate cancer were treated with 35–36.25u2009Gy via SBRT in five fractions. PROs were assessed using EPIC-CP 1u2009h prior to the first fraction and after each subsequent fraction. Symptom management medications were prescribed based on the physician clinical judgment or if patients reported a moderate to big problem. Clinical significance was assessed using a minimally important difference of 1/2 SD from baseline score. Results A median baseline EPIC-CP urinary symptom score of 1.5 significantly increased to 3.7 on the day of the final treatment (pu2009<u20090.0001). Prior to treatment, 9.3% of men felt that their overall urinary function was a moderate to big problem that increased to 28% by the end of the fifth treatment. A median baseline EPIC-CP bowel symptom score of 0.3 significantly increased to 1.4 on the day of the final treatment (pu2009<u20090.0001). Prior to treatment, 1.9% of men felt that their overall bowel function was a moderate to big problem that increased to 3.7% by the end of the fifth treatment. The percentage of patients requiring an increased dose of alpha-antagonist increased to 47% by the end of treatment, and an additional 28% of patients required a short steroid taper to manage moderate to big urinary problems. Similarly, the percentage of patients requiring antidiarrheals reached 12% by the fifth treatment. Conclusion During the course of SBRT, an increasing percentage of patients experienced clinically significant symptoms many of which required medical management. Monitoring patient symptoms during treatment allowed for prompt detection and management of acute urinary and bowel symptoms. The usage of symptom management medications was high in this study compared to historical controls and may be due to increased physician awareness of moderate to big patient problems.

Long-Term Outcomes Following Conventionally Fractionated Stereotactic Boost for High-Grade Gliomas in Close Proximity to Critical Organs at Risk

Purpose/Objective: High-grade glioma is the most common primary malignant tumor of the CNS, with death often resulting from uncontrollable intracranial disease. Radiation dose may be limited by the tolerance of critical structures, such as the brainstem and optic apparatus. In this report, long-term outcomes in patients treated with conventionally fractionated stereotactic boost for tumors in close proximity to critical structures are presented. Materials/Methods: Patients eligible for inclusion in this single institution retrospective review had a pathologically confirmed high-grade glioma status post-surgical resection. Inclusion criteria required tumor location within one centimeter of a critical structure, including the optic chiasm, optic nerve, and brainstem. Radiation therapy consisted of external beam radiation followed by a conventionally fractionated stereotactic boost. Oncologic outcomes and toxicity were assessed. Results: Thirty patients eligible for study inclusion underwent resection of a high-grade glioma. The median initial adjuvant EBRT dose was 50 Gy with a median conventionally fractionated stereotactic boost of 10 Gy. All stereotactic treatments were given in 2 Gy daily fractions. Median follow-up time for the entire cohort was 38 months with a median overall survival of 45 months and 5-year overall survival of 32.5%. The median freedom from local progression was 45 months, and the 5-year freedom from local progression was 29.7%. Two cases of radiation retinopathy were identified following treatment. No patient experienced toxicity attributable to the optic chiasm, optic nerve, or brainstem and no grade 3+ radionecrosis was observed. Conclusions: Oncologic and toxicity outcomes in high-grade glioma patients with tumors in unfavorable locations treated with conventionally fractionated stereotactic boost are comparable to those reported in the literature. This treatment strategy is appropriate for those patients with resected high-grade glioma in close proximity to critical structures.