Quality of Life and Toxicity after SBRT for Organ-Confined Prostate Cancer, a 7-Year Study

Abstract

Objectives: Stereotactic body radiation therapy (SBRT) yields excellent disease control for low- and intermediate-risk prostate cancer by delivering high doses of radiation in a small number of fractions. Our report presents a 7-year update on treatment toxicity and quality of life (QOL) from 515 patients treated with prostate SBRT.Methods: From 2006 to 2009, 515 patients with clinically localized, low-, intermediate-, and high-risk prostate cancer were treated with SBRT using Cyberknife technology. Treatment consisted of 35–36.25 Gy in 5 fractions. Seventy-two patients received hormone therapy. Toxicity was assessed at each follow-up visit using the expanded prostate cancer index composite (EPIC) questionnaire and the radiation therapy oncology group urinary and rectal toxicity scale.Results: Median follow-up was 72 months. The actuarial 7-year freedom from biochemical failure was 95.8, 89.3, and 68.5% for low-, intermediate-, and high-risk groups, respectively (p < 0.001). No patients experienced acute Grade 3 or 4 acute complications. Fewer than 5% of patients had any acute Grade 2 urinary or rectal toxicity. Late toxicity was low, with Grade 2 rectal and urinary toxicity of 4 and 9.1%, respectively, and Grade 3 urinary toxicity of 1.7%. Mean EPIC urinary and bowel QOL declined at 1 month post-treatment, returned to baseline by 2 years and remained stable thereafter. EPIC sexual QOL declined by 23% at 6–12 months and remained stable afterwards. Of patients potent at baseline evaluation, 67% remained potent at last follow-up.Conclusion: This study suggests that SBRT, when administered to doses of 35–36.25 Gy, is efficacious and safe. With long-term follow-up in our large patient cohort, we continue to find low rates of late toxicity and excellent rates of biochemical control.

Stereotactic Body Radiation Therapy for Patients with Early-stage Prostate Cancer

“…Outcome data from eight SBRT studies of patients with early-stage prostate cancer with a combined patient cohort of n=2007 were included (17)(18)(19)(20)(21)(22)(23)(24). This included 1,281 low-risk, 622 intermediate-risk and 104 highrisk patients.…”

“…This included 1,281 low-risk, 622 intermediate-risk and 104 highrisk patients. Rates of bPFS reported ranged from 77.1% to 100% (17)(18)(19)(20)(21)(22)(23)(24), at endpoints ranging 2-7 years post treatment.…”

“…Aim: Stereotactic body radiation therapy (SBRT)is [12][13][14][15][16][17][18][19][20][21][22][23][24][25] respectively,, respectively, in the CF-EBRT cohort. Incidence of acute grade 1, 2, and 3 gastrointestinal toxicities were reported in the range of respectively, of the SBRT cohort compared to 16…”

Dosimetric benefits of hemigland stereotactic body radiotherapy for prostate cancer: implications for focal therapy

“…46 Reported rates of physician-scored toxicities, such as CTCAE and Radiation Therapy Oncology Group grade $3 toxicities, have ranged from 1% to 3%. 27,47 Thus, while acute bowel toxicity is fairly common, it is typically low grade and largely resolved by 6 months post treatment. With regards to dosimetric correlations with GI toxicity, King et al reported that bowel QOL was decreased significantly among patients in the top 25th percentile of rectal V 90% and V 100% .…”

“…28 However, the authors identified a 1.5% incidence of late grade $3 toxicity and noted that the majority of grade 2 toxicities were based on the prescription of medications rather than clinical presentation. Indeed, Katz and Kang 47 reported the incidence of late grade 2 urinary toxicity to be 9.1%. Correlations between GU toxicity and certain dosimetric parameters have also been reported.…”