Salvage Intensity-modulated Radiotherapy Research Articles

Prophylactic Effect of Clarithromycin on Radiation Pneumonitis in IMRT for Lung Cancer.

To evaluate the association between prophylactic administration of clarithromycin (CAM) and the development of radiation pneumonitis (RP) in patients treated with intensity modulated radiation therapy (IMRT) for lung cancer. A total of 89 patients who underwent definitive or salvage IMRT for lung cancer were retrospectively evaluated. The median total and daily doses were 60 Gy and 2 Gy, respectively. A total of 39 patients (44%) received CAM for a median of three months after the start of IMRT. The relationship between the development of RP and certain clinical factors was analyzed. RP of Grade ≥2 was recognized in 10 (11%) patients; Grade 2 in six patients and Grade 3 in four patients. The incidence of Grade ≥2 RP was 3% (1/39) in patients treated with CAM, which was significantly lower than that of 18% (9/50) in patients without CAM. The median lung V20 and V5 in the 10 patients with RP Grade ≥2 were 24% and 46%, respectively, compared with 18% and 37% in the 79 patients with RP Grade 0-1, and the differences were significant. Durvalumab administration after IMRT was also a significant factor for RP Grade ≥2. Prophylactic administration of CAM may reduce Grade ≥2 RP in patients treated with IMRT for lung cancer. Therefore, further clinical trials are warranted.

Impact of Radiotherapy Combined With Chemotherapy on Long-Term Outcomes of Patients With Recurrent Nasopharyngeal Carcinoma.

Background: It remains controversial whether the application of chemotherapy has an impact on recurrent nasopharyngeal carcinoma (rNPC) patients with salvage radiotherapy. Here, we aimed to evaluate treatment outcomes of rNPC patients and derive a prognostic model to assess the benefit of chemotherapy in patients with re-radiotherapy. Methods: This study was conducted as a retrospective study. In total, 340 rNPC patients treated with salvage intensity-modulated radiotherapy (IMRT) or radiochemotherapy (RCT) from October 2006 to September 2019 were included in this study. Overall survival (OS) was the primary outcome. Kaplan-Meier method was employed to detect the prognostic difference with Log-rank tests. The Cox regression analysis was performed to explore the potential prognostic factors while the multivariate Cox analysis was used to identify candidate variables for the prognostic model of OS. Results: The 5-year actuarial rates of OS, progression-free survival, loco-regional progression-free survival, and distant metastases-free survival did not show significant difference between the IMRT and RCT groups (P > .05). Age at recurrence and rT category were found to be the independent prognostic factors for OS. We found that rNPC patients suffered poor OS in the high-risk group (patients with higher age at recurrence and advanced rT category) (high-risk vs low-risk, HR = 1.87, 95% CI: 1.36-2.57, P < .001). Salvage RT alone may be superior to RCT for patients in the low-risk group (RCT group vs RT group, HR = 1.89, 95% CI: 1.11-3.20, P = .038). Conclusion: Salvage RT combined with chemotherapy cannot improve survival outcomes for rNPC. More novel clinical trials should be explored to develop individualized strategies to improve survival and minimize toxicities.

P035 - Choline PET guided salvage intensity modulated radiation therapy (sIMRT) for Oligometastatic Castrate Resistant Prostate Cancer (OCRPC)

P035 - Choline PET guided salvage intensity modulated radiation therapy (sIMRT) for Oligometastatic Castrate Resistant Prostate Cancer (OCRPC)

Comparative toxicity outcomes of proton-beam therapy versus intensity-modulated radiotherapy for prostate cancer in the postoperative setting.

Despite increasing utilization of proton-beam therapy (PBT) in the postprostatectomy setting, no data exist regarding toxicity outcomes relative to intensity-modulated radiotherapy (IMRT). The authors compared acute and late genitourinary (GU) and gastrointestinal (GI) toxicity outcomes in patients with prostate cancer (PC) who received treatment with postprostatectomy IMRT versus PBT. With institutional review board approval, patients with PC who received adjuvant or salvage IMRT or PBT (70.2 gray with an endorectal balloon) after prostatectomy from 2009 through 2017 were reviewed. Factors including combined IMRT and PBT and/or concurrent malignancies prompted exclusion. A case-matched cohort analysis was performed using nearest-neighbor 3-to-1 matching by age and GU/GI disorder history. Logistic and Cox regressions were used to identify univariate and multivariate associations between toxicities and cohort/dosimetric characteristics. Toxicity-free survival (TFS) was assessed using the Kaplan-Meier method. Three hundred seven men (mean±SD age, 59.7±6.3years; IMRT, n=237; PBT, n=70) were identified, generating 70 matched pairs. The median follow-up was 48.6 and 46.1months for the IMRT and PBT groups, respectively. Although PBT was superior at reducing low-range (volumes receiving 10% to 40% of the dose, respectively) bladder and rectal doses (all P ≤ .01), treatment modality was not associated with differences in clinician-reported acute or late GU/GI toxicities (all P≥.05). Five-year grade ≥2 GU and grade ≥1 GI TFS was 61.1% and 73.7% for IMRT, respectively, and 70.7% and 75.3% for PBT, respectively; and 5-year grade ≥3 GU and GI TFS was >95% for both groups (all P≥.05). Postprostatectomy PBT minimized low-range bladder and rectal doses relative to IMRT; however, treatment modality was not associated with clinician-reported GU/GI toxicities. Future prospective investigation and ongoing follow-up will determine whether dosimetric differences between IMRT and PBT confer clinically meaningful differences in long-term outcomes.

Outcomes after a first and/or second salvage treatment in patients with oligometastatic prostate cancer recurrence detected by (18‐F) choline PET‐CT

The primary objective of this study was to assess clinical outcomes in patients with oligometastatic prostate cancer recurrence after single or repeated salvage radiation treatment. Forty-nine consecutive prostate cancer patients diagnosed with oligometastatic recurrence on Ch-PET have been prospectively treated. Seven (23%) patients had castrate-resistant disease. Clinical outcomes were assessed using the Kaplan-Meier method. Potential prognostic factors were examined using univariate proportional hazards regression. The treatments administered to the initial oligorecurrence sites were intensity-modulated radiotherapy (IMRT)±ADT (26 patients; 53%) and stereotactic ablative radiotherapy (SABR)±ADT (23 patients; 47%). With a median follow-up of 24months (range 6-39), 24 patients developed a biochemical failure. Twenty out of the 24 relapsed patients underwent a second Ch-PET/CT. Seven patients presented poly-metastatic relapse and 10 oligometastatic diseases. Six of 10 patients with a second oligorecurrence were treated again with SABR. Overall, 102 lesions were treated. Local control was detected in 45 (91.8%) patients. No relevant (grade≥2) toxicity was reported, and there was no grade 3 toxicity. On univariate analysis, none of the variables were significantly predicted for clinical disease-free survival. At last follow-up visit, 24 patients (40%) were free from biochemical failure and 37 (71%) patients were free from clinical disease. The 2-year OS and PCSS were 91.8% and 95.9% respectively. Salvage IMRT or SBRT of oligometastatic prostate cancer recurrence is associated with a prolonged cDFS. This may result in a longer time to develop castrate-resistant disease and a longer time without systemic therapies.

Prognostic Model for Stratification of Radioresistant Nasopharynx Carcinoma to Curative Salvage Radiotherapy

Purpose To investigate for a prognostic index (PI) to personalize recommendations for salvage intensity-modulated radiotherapy (IMRT) in patients with locally recurrent nasopharyngeal carcinoma (lrNPC). Methods Patients with lrNPC from two academic institutions (Sun Yat-Sen University Cancer Center [SYSUCC-A; n = 251 (training cohort)] and National Cancer Centre Singapore [NCCS; n = 114] and SYSUCC-B [n = 193 (validation cohorts)]) underwent salvage treatment with IMRT from 2001 to 2015. Primary and secondary clinical end points were overall survival (OS) and grade 5 toxicity-free rate (G5-TFR), respectively. Covariate inclusion to the PIs was qualified by a multivariable two-sided P < .05. Discrimination and calibration of the PIs were assessed. Results The primary PI comprised covariates that were adversely associated with OS in the training cohort (gross tumor volumerecurrence hazard ratio [HR], 1.01/mL increase [ P < .001], agerecurrence HR, 1.02/year increase [ P = .008]; repeat IMRT equivalent dose in 2-Gy fractions [EQD2] ≥ 68 Gy HR, 1.42 [ P = .03]; prior radiotherapy-induced grade ≥ 3 toxicities HR, 1.90 [ P = .001]; recurrent tumor [rT]-category 3 to 4 HR, 1.96 [ P = .005]), in ascending order of weight. Discrimination of the PI for OS was comparable between training and both validation cohorts (Harrell's C = 0.71 [SYSUCC-A], 0.72 [NCCS], and 0.69 [SYSUCC-B]); discretization by using a fixed PI score cutoff of 252 determined from the training data set yielded low- and high-risk subgroups with disparate OS in the validation cohorts (NCCS HR, 3.09 [95% CI, 1.95 to 4.89]; SYSUCC-B HR, 3.80 [95% CI, 2.55 to 5.66]). Our five-factor PI predicted OS and G5-TFR (predicted v observed 36-month OS and G5-TFR, 22% v 15% and 38% v 44% for high-risk NCCS and 26% v 31% and 45% v 46% for high-risk SYSUCC-B). Conclusion We present a validated PI for robust clinical stratification of radioresistant NPC. Low-risk patients represent ideal candidates for curative repeat IMRT, whereas novel clinical trials are needed in the unfavorable high-risk subgroup.

Image-guided, whole-pelvic, intensity-modulated radiotherapy for biochemical recurrence following radical prostatectomy in high-risk prostate cancer patients.

BackgroundThe optimal field size of salvage radiotherapy (SRT) for biochemical recurrence, particularly for patients with high-risk prostate cancer, remains undefined. This retrospective analysis was performed to investigate oncological outcomes as well as treatment-related toxicity following salvage intensity-modulated radiotherapy (IMRT) to the whole pelvis and to compare the results with other studies implementing a small field size of the prostate bed.MethodsThe medical records of 170 patients with high-risk prostate cancer who received SRT for biochemical recurrence following prostatectomy were reviewed. Whole-pelvic IMRT was administered with a median dose of 66 Gy in 30 fractions. To improve treatment accuracy, an endorectal balloon device and daily cone-beam computed tomography were utilized. Androgen-deprivation therapy combined with SRT was administered to 97 (57.1%) patients.ResultsEventually, 68 (40.0%) patients showed biochemical progression (BCP) after SRT. With a median follow-up period of 56 months, the 5-year BCP-free survival was 38.6%. The overall and cause-specific survival rates were 90.9% and 96.7%, respectively. Regarding BCP-free survival analysis, pathological T stage, persistent prostate-specific antigen (PSA) elevation after prostatectomy, and preSRT PSA level were significant prognostic factors on univariate analysis. On multivariate analysis, pathological T stage and preSRT PSA value retained their significance. Acute and late grade-3 genitourinary toxicities were observed in one (0.6%) and five (2.9%) patients, respectively. One patient each developed acute and late grade-3 gastrointestinal toxicity.ConclusionSRT to whole pelvis using IMRT and image guidance is as safe as SRT to the prostate bed, but its efficacy should be confirmed in ongoing randomized trials. PreSRT PSA was the only controllable prognostic factor, suggesting the benefit of early SRT.

268P - Image-guided, whole-pelvic, intensity-modulated radiotherapy for biochemical recurrence following radical prostatectomy in high-risk prostate cancer patients

Background: The optimal field size of salvage radiotherapy (SRT) for biochemical recurrence, particularly for patients with high-risk prostate cancer, remains undefined. This retrospective analysis was performed to investigate oncological outcomes as well as treatment-related toxicity following salvage intensity-modulated radiotherapy (IMRT) to the whole pelvis and to compare the results with other studies implementing a small field size of the prostate bed. Methods: The medical records of 170 patients with high-risk prostate cancer who received SRT for biochemical recurrence following prostatectomy were reviewed. Whole-pelvic IMRT was administered with a median dose of 66 Gy in 30 fractions. To improve treatment accuracy, an endorectal balloon device and daily cone-beam computed tomography were utilized. Androgen-deprivation therapy combined with SRT was administered to 97 (57.1%) patients. Results: Eventually, 68 (40.0%) patients showed biochemical progression (BCP) after SRT. With a median follow-up period of 56 months, the 5-year BCP-free survival was 38.6%. The overall and cause-specific survival rates were 90.9% and 96.7%, respectively. Regarding BCP-free survival analysis, pathological T stage, persistent prostate-specific antigen (PSA) elevation after prostatectomy, and preSRT PSA level were significant prognostic factors on univariate analysis. On multivariate analysis, pathological T stage and preSRT PSA value retained their significance. Acute and late grade-3 genitourinary toxicities were observed in one (0.6%) and five (2.9%) patients, respectively. One patient each developed acute and late grade-3 gastrointestinal toxicity. Conclusions: SRT to whole pelvis using IMRT and image guidance is as safe as SRT to the prostate bed, but its efficacy should be confirmed in ongoing randomized trials. PreSRT PSA was the only controllable prognostic factor, suggesting the benefit of early SRT. Legal entity responsible for the study: IRB of Asan Medical Center Funding: None Disclosure: The author has declared no conflicts of interest.

Simplified Predictive Nomogram By High-Dose Salvage Intensity Modulated Radiation Therapy after Radical Prostatectomy for Prostate Cancer

Simplified Predictive Nomogram By High-Dose Salvage Intensity Modulated Radiation Therapy after Radical Prostatectomy for Prostate Cancer

Salvage Intensity Modulated Radiation Therapy (IMRT) for Locally Recurrent Nasopharyngeal Cancer After Definitive IMRT: Treatment Outcomes of a Clinically Distinct Condition in the Modern Era

Salvage Intensity Modulated Radiation Therapy (IMRT) for Locally Recurrent Nasopharyngeal Cancer After Definitive IMRT: Treatment Outcomes of a Clinically Distinct Condition in the Modern Era

Salvage Intensity-Modulated Radiation Therapy (IMRT) for Locally Recurrent Nasopharyngeal Cancer after Definitive IMRT: A Novel Scenario of the Modern Era.

Locally recurrent nasopharyngeal carcinoma (rNPC) after definitive IMRT occurs in 10% of all cases and represents a distinct clinical entity that has been selectively enriched by radio-resistant cancer cells. Therefore, we report of the outcomes of 77 patients who had repeat salvage-IMRT for rNPC after only a definitive course of IMRT. Various clinical outcomes were measured. Log-rank tests were used to detect differences in the survival outcomes between factor-defined subgroups. Multivariable analysis was performed using the Cox proportional hazard model. The median follow-up time was 25.7 months (range 3.0–75.7 months), measured from the time of recurrence. The median OS time and PFS time of the entire cohort was 37.0 and 20.5 months, respectively. Thirty-four patients (44.2%) died. Approximately 35% of these patients died from disease progression, but 53% were from treatment-induced severe adverse effects (SAEs) without evidence of disease progression. Higher T-classification of the recurrent tumor and the development of SAEs were found to be the only independent and significant adverse prognostic factors on multivariable analysis. These outcomes underscore the particularly virulent characteristics of rNPC after definitive IMRT. Concerning is the impact of re-irradiation toxicity on patient mortality.

Dual-timing PSA as a biomarker for patients with salvage intensity modulated radiation therapy for biochemical failure after radical prostatectomy.

We investigated the outcomes and the associated clinical-pathological factors in patients with prostate cancer (PCa) undergoing salvage intensity modulated radiation therapy (IMRT) for post-radical-prostatectomy (RP) biochemical failure. We report clinical outcomes of post-RP salvage IMRT, and describe chronic toxicity in these patients.Fifty patients with PCa underwent post-RP salvage IMRT. The median dose of IMRT was 70 Gy to the prostatic and seminal vesicle bed. Clinical-pathological and toxicity information were collected. The prostate cancer-specific survival (PCSS), disease-free survival (DFS), and biochemical-failure-free survival (BFFS) were calculated. Prognostic factors were analyzed for their association with disease control.The median follow-up time was 74 months. The 5-year PCSS, DFS, and BFFS after salvage IMRT were 95%, 88%, and 60%, respectively. Two patients (4%) experienced late gastrointestinal toxicity ≥ grade 3, and 5 patients (10%) had late genitourinary toxicity ≥ grade 3. On multivariate analysis, post-RP prostate-specific antigen (PSA) nadir ≤0.1 ng/ml (P=0.018) and PSA ≤0.5 ng/ml at salvage IMRT (P=0.016) were independent factors predicting better BFFS. Patients with both post-RP PSA nadir ≤0.1 ng/ml and PSA ≤0.5 ng/ml at salvage IMRT had a 5-year BFFS of 83% as compared with 43% in other patients (P=0.001).In conclusion, with hormonal therapy in most PCa patients, the addition of salvage IMRT for post-RP biochemical failure can achieve a good outcome with low toxicity. Patients with a post-RP PSA nadir ≤0.1 ng/ml and PSA ≤0.5 ng/ml at salvage IMRT could benefit the most from salvage IMRT.

Intensity Modulated Radiation Therapy for Early-Stage Primary Gastric Diffuse Large B-Cell Lymphoma: Dosimetric Analysis, Clinical Outcome, and Quality of Life

To evaluate the dosimetric superiority, efficacy, toxicity, and quality of life (QOL) data of intensity modulated radiation therapy (IMRT) in patients with primary gastric diffuse large B-cell lymphoma (PG-DLBCL). Forty-six consecutive patients with early-stage PG-DLBCL underwent IMRT after chemotherapy. The majority of patients (61.5%) were subclassified as the non-germinal center Bcell-like subtype. Dosimetric parameters of the planning target volume (PTV) and organs at risk were assessed. Survival rates were depicted with the Kaplan-Meier method and compared with the log-rank test. Quality of life was evaluated using the QLQ-C30-STO22 questionnaires at the last follow-up contact. The median PTV mean dose was 41.6Gy. Only 0.73% of the PTV received <95% of the prescribed dose, indicating excellent target coverage. The median kidney V20 and liver V30 were 14.1% and 16.1%, respectively. The 5-year overall survival (OS), progression-free survival, and locoregional control rates for all patients were 80.4%, 75.0%, and 93.2%, respectively. Stage, lactate dehydrogenase level, and immunophenotype were significant prognostic factors for OS, and only stage was a significant factor for locoregional control. Consolidation IMRT in patients with complete response after chemotherapy resulted in significantly better OS and progression-free survival than salvage IMRT in patients with non-complete response. Two of 8 patients who had chronic liver disease experienced grade 4 or grade 5 acute hepatic failure after 4 to 5 cycles of rituximab-based chemotherapy and IMRT (40Gy). No other serious acute or late toxicity was observed. The long-term global and functional QOL scales were excellent, with negligible symptom scales. Intensity modulated radiation therapy yielded excellent target coverage and critical tissue sparing and achieved favorable outcomes with acceptable toxicity and good long-term QOL in early-stage PG-DLBCL.

Bladder dose-volume parameters are associated with urinary incontinence after postoperative intensity modulated radiation therapy for prostate cancer

PurposeUrinary incontinence is a potential side effect of prostatectomy and intensity modulated radiation therapy (IMRT) for prostate cancer. There are limited data on dosimetric parameters that may predict for poor continence recovery in men who receive postoperative IMRT. Methods and materialsEighty-seven men with nonmetastatic prostate cancer who underwent prostatectomy followed by adjuvant (13%) or salvage (87%) IMRT were identified. The Expanded Prostate Cancer Index composite questionnaire was prospectively collected at baseline, 6 weeks, and 6, 12, 18, 24, 36, and 48 months post-IMRT. Relevant critical structures were contoured and dose-volume metrics collected. The primary endpoint was urinary continence global score. Longitudinal analysis using a generalized estimating equation model was performed. ResultsThere was no statistically significant change in Expanded Prostate Cancer Index composite urinary continence global scores over time as compared with baseline (all P > .05). In univariate analysis, bladder volume receiving 70 Gy (V70 Gy) and penile bulb V70 Gy were associated with urinary continence (odds ratio, 0.82; P < .05). In a multivariable model that included body mass index, distance between vesicourethral junction and genitourinary diaphragm, time from surgery, use of antihypertensive medications, age, diabetes, and bladder V70 Gy, only bladder V70 Gy (odds ratio, 0.82; P = .03) was associated with outcome. After 2 years, there was a significant difference in global score for those with V70 Gy < 42.27 versus ≥42.27 mL (all P < .05 at 2 and 3 years post-IMRT). ConclusionThere was no significant change in patient-reported urinary continence scores after postprostatectomy IMRT. Bladder V70 Gy was independently associated with a decrease in urinary continence scores. Further evaluation is necessary to optimize quality of life in these men.

Prognostic significance of tumor volume in locally recurrent nasopharyngeal carcinoma treated with salvage intensity-modulated radiotherapy.

IntroductionTo evaluate the prognostic value of gross tumor volume (TV) in patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma.MethodsBetween 2001 and 2012, 291 consecutive patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma underwent salvage IMRT were retrospectively reviewed. The correlations between TV and recurrent T classification were analyzed. Survival analyses were performed. Receiver operating characteristic (ROC) curves were calculated to identify cut-off point of TV. The Akaike information criterion and Harrell’s concordance index (c-index) were utilized to test the prognostic value.ResultsThe median TV significantly increased with advancing recurrent T classification (P<0.001). The 5-year overall survival rate was 33.2% for the entire cohort. On multivariate analysis, TV was an independent negative prognostic factor for distant metastasis-free survival (hazard ratio =1.013, P =0.003), overall survival (hazard ratio = 1.015, P<0.001) and toxicity-related death (hazard ratio = 1.014, P<0.001). The 5-year overall survival rates were 63.1% and 20.8% for patients with a TV < 22 cm3 and TV ≥22 cm3, respectively (P < 0.001). In patient with TV <22 cm3, locoregional failure is the leading cause of death. In patients with TV≥22 cm3, distant metastasis rate is higher and occurred within short term after local recurrence; meanwhile, radiation-induced injuries became more common and led to half of deaths in this group. The Akaike information criterion and c-index analyses indicated that the predictive ability of recurrent T classification improved when combined with TV.ConclusionsOur data suggests TV is a significant prognostic factor for predicting the distant metastasis, overall survival and toxicity-related death of patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma after salvage IMRT. TV should be considered when designing personalized salvage treatments for these patients. For patients with bulky local recurrent tumor, radiation may need to be de-emphasized in favor of systemic treatment or best supportive care.

Editorial Comment to Salvage intensity modulated radiotherapy using endorectal balloon after radical prostatectomy: Clinical outcomes

Editorial Comment to Salvage intensity modulated radiotherapy using endorectal balloon after radical prostatectomy: Clinical outcomes

Salvage intensity modulated radiotherapy using endorectal balloon after radical prostatectomy: Clinical outcomes

To evaluate biochemical non-evidence of disease and adverse events of salvage intensity-modulated radiotherapy using an endorectal balloon for prostate cancer patients after radical prostatectomy. Data of 107 patients (median age 65 years) with persistent (>0.1 ng/mL) or rising prostate-specific antigen after radical prostatectomy were retrospectively analyzed. The mean dose to clinical target volume was 70 Gy in 32 fractions (the equivalent dose in 2 Gy fraction is 73.2 Gy based on α:β = 2). Biochemical non-evidence of disease and predictive factors were assessed. Genitourinary toxicity and gastrointestinal toxicity were also evaluated using the Radiation Therapy Oncology Group toxicity criteria. The median follow up was 37 months (range 6-126 months). A total of 48 patients developed biochemical recurrence. The 3- and 5-year biochemical non-evidence of disease rates of all patients were 52.6% and 48.8%, respectively. The Gleason score (≥4 + 3, ≤3 + 4) and pre-intensity-modulated radiotherapy prostate-specific antigen level (≥0.5 ng/mL, <0.5 ng/mL) were significant predictive factors for biochemical non-evidence of disease in univariate analysis. In multivariate analysis, only the Gleason score was detected as a significant variable. The highest late genitourinary toxicities were grade 2 in 13% and grade 3 in 6% of patients. The highest late gastrointestinal toxicities were grade 2 in 6% and grade 3 in 3% of patients. Despite a relatively high radiation dose, intensity-modulated radiotherapy with an endorectal balloon can be delivered with acceptable toxicity and efficacy for patients developing biochemical recurrence after radical prostatectomy.

EP-1095: Salvage intensity-modulated radiation therapy for PSA failure after prostatectomy

EP-1095: Salvage intensity-modulated radiation therapy for PSA failure after prostatectomy

Analysis of True Delivered Dose to the Prostate Fossa Utilizing Daily Cone Beam CT in Postprostatectomy Patients Who Failed Salvage Intensity Modulated Radiation Therapy

Analysis of True Delivered Dose to the Prostate Fossa Utilizing Daily Cone Beam CT in Postprostatectomy Patients Who Failed Salvage Intensity Modulated Radiation Therapy S. Stanic, J. Cui, K. Ding, D.B. Halket, and R.K. Valicenti; University of California Davis, Department of Radiation Oncology, Sacramento, CA, University of California Davis, Division of Biostatistics, Department of Public Health Sciences, Davis, CA, University of California Berkeley, Post-baccalaureate Program, Berkeley, CA

Health‐related quality of life using intensity‐modulated radiation therapy for post‐prostatectomy radiotherapy

Post-prostatectomy radiotherapy (PPRT) with intensity-modulated radiation therapy (IMRT) has the potential to decrease toxicity by reducing dose to surrounding structures. We assessed its impact on health-related quality of life (HRQoL). PPRT patients were enrolled in a prospective HRQoL database. To be eligible, patients were required to be treated with IMRT and have a minimum of 15-month follow up. HRQoL was assessed at baseline, 3, 9 and 15-24 months using the Expanded Prostate Cancer Index Composite questionnaire. Higher scores reflected better HRQoL. Results were analysed as both population means and as individual scores where a moderate change was 10-20 points and a substantial change was >20 points. There were 64 patients eligible and 83% of the cohort received salvage radiotherapy. Prescribed dose was 64 Gy in 32 fractions for adjuvant and 66 Gy in 33 fractions for salvage IMRT. Mean function scores for urinary, bowel and sexual domains were similar at baseline and 15 months (83.5, 94.2 and 16.9 vs. 82.2, 93.1 and 14.3, respectively). Mean global physical functioning (51.0 vs. 48.1) and mental functioning (51.6 vs. 54.2) showed no difference over time. Individual patient scores by 2 years showed a >20-point deterioration in urinary (12.5%), bowel (1.6%), sexual function (9.4%), physical functioning (3.1%) and mental functioning (1.6%). This report on HRQoL following post-prostatectomy IMRT demonstrates no variation in mean scores in any domain and only 1.6% of patients reporting a greater than 20-point deterioration between baseline and 15-24 months in bowel function.