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Background: 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.Methods: 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.Results: Three hundred seven men (mean ± SD age, 59.7 ± 6.3 years; IMRT, n = 237; PBT, n = 70) were identified, generating 70 matched pairs. The median follow-up was 48.6 and 46.1 months 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).Conclusions: 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. [ABSTRACT FROM AUTHOR]

Purpose: In up to half of patients treated with salvage radiation therapy (SRT) for rising prostate-specific antigen levels, a second biochemical recurrence ultimately develops. Phosphatase and tensin homolog inactivation is implicated in prostate cancer progression, and upregulation of the mammalian target of rapamycin pathway can lead to tumor hypoxia and radioresistance. Everolimus is a mammalian target of rapamycin inhibitor with both antitumor and radiosensitizing effects.Methods and Materials: We performed a phase 1 study using a modified 3 + 3 dose-escalation design to evaluate the safety and tolerability of everolimus in combination with standard SRT for the treatment of biochemical recurrence following prostatectomy. After a 2-week run-in period of everolimus daily therapy, patients received prostate bed irradiation with daily cone beam computed tomography localization in 37 fractions of 1.8 Gy each (total dose, 66.6 Gy). Patients were monitored for both acute (≤90 days) and chronic (>90 days) treatment-related toxicities.Results: Eighteen patients received everolimus at dose levels of 5 mg (n=6), 7.5 mg (n=6), or 10 mg (n=6) daily in conjunction with SRT. No dose-limiting toxicities were observed. Common acute treatment-related toxicities included grade 1 or 2 mucositis (55.6%), grade 1 or 2 fatigue (38.9%), grade 1 or 2 rash (61.1%), and grade 1 urinary symptoms (61.1%). A grade 3 acute toxicity occurred in 4 patients (22.2%) (n=1 for rash, anemia, lymphopenia, and neutropenia), and no patients had a chronic toxicity of grade 3 or greater. After a median follow-up time of 17.8 months (range, 1.2-46.0 months), an undetectable prostate-specific antigen nadir was achieved in 9 patients (56.3%) and a second biochemical recurrence developed in 5 patients (31.3%).Conclusions: Everolimus at a dose of ≤10 mg daily appears to be safe and tolerable in combination with fractionated post-prostatectomy radiation therapy. [ABSTRACT FROM AUTHOR]

BACKGROUND The authors assessed whether proton beam therapy (PBT) for prostate cancer (PCa) was associated with differing toxicity compared with intensity-modulated radiation therapy (IMRT) using case-matched analysis. METHODS From 2010 to 2012, 394 patients who had localized PCa received 79.2 Gray (Gy) relative biologic effectiveness (RBE) delivered with either PBT (181 patients) or IMRT (213 patients). Patients were case-matched on risk group, age, and prior gastrointestinal (GI) and genitourinary (GU) disorders, resulting in 94 matched pairs. Both exact matching (risk group) and nearest-neighbor matching (age, prior GI/GU disorders) were used. Residual confounding was adjusted for by using multivariable regression. Maximum acute and late GI/GU Common Terminology Criteria for Adverse Events-graded toxicities were compared using univariate and multivariable logistic and Cox regression models, respectively. RESULTS Bladder and rectum dosimetry variables were significantly lower for PBT versus IMRT ( P ≤ .01). The median follow-up was 47 months (range, 5-65 months) for patients who received IMRT and 29 months (range, 5-50 months) for those who received PBT. On multivariable analysis, which exploited case matching and included direct adjustment for confounders and independent predictors, there were no statistically significant differences between IMRT and PBT in the risk of grade ≥2 acute GI toxicity (odds ratio, 0.27; 95% confidence interval [CI], 0.06-1.24; P = .09), grade ≥2 acute GU toxicity (odds ratio, 0.69; 95% CI, 0.32-1.51; P = .36), grade ≥2 late GU toxicity (hazard ratio, 0.56; 95% CI, 0.22-1.41; P = .22), and grade ≥2 late GI toxicity (hazard ratio, 1.24; 95% CI, 0.53-2.94; P = .62). CONCLUSIONS In this matched comparison of prospectively collected toxicity data on patients with PCa who received treatment with contemporary IMRT and PBT techniques and similar dose-fractionation schedules, the risks of acute and late GI/GU toxicities did not differ significantly after adjustment for confounders and predictive factors. Cancer 2015;121:1118-1127. © 2014 American Cancer Society. [ABSTRACT FROM AUTHOR]

Purpose: To assess whether whole-pelvis (WP) intensity modulated radiation therapy (IMRT) for prostate cancer (PCa) after prostatectomy is associated with increased toxicity compared to prostate-bed only (PB) IMRT. Methods and Materials: All patients (n = 67) undergoing postprostatectomy IMRT to 70.2 Gy at our institution from January 2006 to January 2009 with minimum 12-month follow-up were divided into WP (n = 36) and PB (n = 31) comparison groups. WP patients received initial pelvic nodal IMRT to 45 Gy. Pretreatment demographics, bladder and rectal dose-volume histograms, and maximum genitourinary (GU) and gastrointestinal (GI) toxicities were compared. Logistic regression models evaluated uni- and multivariate associations between pretreatment demographics and toxicities. Results: Pretreatment demographics including age and comorbidities were similar between groups. WP patients had higher Gleason scores, T stages, and preoperative prostate-specific antigen (PSA) levels, and more WP patients underwent androgen deprivation therapy (ADT). WP minimum (Dmin) and mean bladder doses, bladder volumes receiving more than 5 Gy (V5) and V20, rectal Dmin, and PB bladder and rectal V65 were significantly increased. Maximum acute GI toxicity was Grade 2 and was increased for WP (61%) vs. PB (29%) patients (p = 0.001); there was no significant difference in acute Grade ≥2 GU toxicity (22% WP vs. 10% PB; p = 0.193), late Grade ≥2 GI toxicity (3% WP vs. 0% PB; p = 0.678), or late Grade ≥2 GU toxicity (28% WP vs. 19% PB; p = 0.274) with 25-month median follow-up (range, 12–44 months). On multivariate analysis, long-term ADT use was associated with Grade ≥2 late GU toxicity (p = 0.02). Conclusion: Despite dosimetric differences in irradiated bowel, bladder, and rectum, WP IMRT resulted only in clinically significant increased acute GI toxicity in comparison to that with PB IMRT, with no differences in GU or late GI toxicity. [Copyright &y& Elsevier]

Management of ductal carcinoma in situ (DCIS) of the breast is controversial, as not all patients progress to invasive carcinoma. This report analyzes the outcomes after breast conservation treatment (BCT) with radiation in patients with DCIS following prior malignancy at another anatomic site. The study cohort was comprised of 14 women with DCIS who were treated between 1978 and 2003. The median age at diagnosis of DCIS was 54 years (mean 56; range 37–78) and for the prior nonbreast malignancy was 44 years (mean 47; range 27–76). All patients underwent breast conservation surgery followed by whole breast radiation and tumor bed boost. The median and mean follow-up times after treatment of DCIS were 8.0 and 9.1 years, respectively (range 2–18). The median and mean interval period between the prior malignancy and DCIS was 6.0 and 8.2 years, respectively (range 1–30). There was one (7%) local failure, two (14%) contralateral breast cancers, and one (7%) death from breast cancer that occurred 7 years after BCT following contralateral invasive breast cancer. In this cohort of 14 patients treated for DCIS of the breast after a prior nonbreast malignancy, treatment for DCIS resulted in a high rate of local control and should be considered for curative intent. [ABSTRACT FROM AUTHOR]

Purpose: To report the long-term outcomes for women presenting with regional lymph node recurrence after breast conservation treatment with radiotherapy for Stage I and II invasive breast carcinoma. Methods and Materials: Of the women with pathologic Stage I and II invasive breast carcinoma treated with breast conservation treatment at the University of Pennsylvania, 29 developed regional nodal recurrence as their first site of failure. An analysis of the patterns of regional nodal recurrence and their prognosis after recurrence was undertaken. The median follow-up from regional nodal recurrence was 5.4 years. Results: The pattern of regional nodal recurrence was as follows: 14 (48%) with simultaneous local and axillary recurrence, 7 (24%) with recurrence in the axilla only, 5 (17%) with recurrence in the supraclavicular region only, and 3 (10%) with multiple nodal sites of recurrence. For the entire study group, the 5-, 10-, and 15-year overall survival rate was 70%, 37%, and 28%, respectively. The 10-year overall survival rate for patients with locoregional recurrence was 32% compared with 45% for patients with regional-only recurrence (p = 0.50). The 10-year overall survival rate for patients with axillary recurrence discovered on pathologic examination of the mastectomy specimen was 31% compared with 42% for patients with palpable regional lymphadenopathy (p = 0.83). Conclusion: Patients with regional nodal recurrence after breast conservation treatment with radiotherapy for early-stage breast carcinoma are potentially salvageable. The prognosis after regional nodal recurrence was not significantly different when stratified by the presence or absence of simultaneous in-breast recurrence or the method of detection. [Copyright &y& Elsevier]

Purpose: Little information has been reported regarding outcomes after treatment for patients with early-stage invasive breast cancer and a prior nonbreast malignancy. This report analyzes the outcomes in patients with Stage I and II breast cancer after breast conservation treatment (BCT) with a prior nonbreast malignancy. Methods and Materials: The study cohort comprised 66 women with invasive breast cancer and a prior nonbreast malignancy. All patients were treated with breast conservation surgery followed by definitive breast irradiation between 1978 and 2003. Median ages at diagnosis of invasive breast cancer and prior malignancy were 57 and 50 years, respectively. The median interval between the prior malignancy and breast cancer was 7.0 years. Median and mean follow-up times after BCT were 5.3 and 7.0 years. Results: The 5-year and 10-year overall survival rates were 94% (95% confidence interval [CI], 82–98%) and 78% (95% CI, 59–89%), respectively. There were 4 patients (6%) with local failure and 10 patients (15%) with distant metastases. The 10-year rate of local failure rate was 5% (95% CI, 2–16%) and freedom from distant metastases was 78% (95% CI, 61–88%). No obvious differences in survival or local control were noted compared with the reported results in the literature for patients with invasive breast cancer alone. Conclusions: Both overall survival and local control at 5 and 10 years were comparable to rates observed in early-stage breast cancer patients without a prior malignancy. Prior nonbreast malignancy is not a contraindication to BCT, if the primary cancer is effectively controlled. [Copyright &y& Elsevier]

Purpose: Acute hospital encounters in patients undergoing curative-intent radiation therapy (RT) have not previously been well characterized. Understanding acute visit patterns among RT patients yields insights for risk assessments and cancer urgent care clinics that could decrease hospitalization rates and reduce health care costs. This study aims to identify patient, disease-site, and treatment characteristics associated with emergency department visits and inpatient admissions in cancer patients treated with definitive RT.Methods and Materials: A retrospective cohort study was conducted using data from a quaternary-care cancer center. The cohort was defined as all consecutive patients aged ≥ 18 years who began RT between July 1, 2011, and December 31, 2013; were without metastases; and were treated with curative intent. An acute encounter was defined as an emergency department visit or inpatient admission during RT or within 30 days after the conclusion of RT.Results: Among 1852 unique RT courses, 666 RT courses (36.0%) involved at least 1 acute encounter, and a total of 1418 acute encounters were identified. RT courses with at least 1 acute encounter corresponded to patients more likely to be on their second (odds ratio [OR], 1.96; P < .001) or third (OR, 3.82; P < .05) RT course and undergoing concurrent chemotherapy (OR, 6.38; P < .001). Among the RT courses with at least 1 acute encounter, the most common disease site was thoracic (22.8%), followed by head and/or neck (22.2%) and gastrointestinal (18.3%). Central nervous system tumors had the greatest proportion of RT courses with acute encounters (77.1%).Conclusions: In this retrospective analysis, more than one-third of curative-intent RT courses were associated with at least 1 acute hospital encounter during or shortly after irradiation. Given that acute encounters varied by patient, disease-site, and treatment characteristics, these findings can inform targeted preventive measures to reduce cancer-related acute hospital encounters and guide improved management protocols. [ABSTRACT FROM AUTHOR]

Trials of adjuvant radiation after cystectomy are under development. There are no studies comparing radiation techniques to inform trial design. This study assesses the effect on bowel and rectal dose of 3 different modalities treating 2 proposed alternative clinical target volumes (CTVs). Contours of the bowel, rectum, CTV-pelvic sidewall (common/internal/external iliac and obturator nodes), and CTV-comprehensive (CTV-pelvic sidewall plus cystectomy bed and presacral regions) were drawn on simulation images of 7 post-cystectomy patients. We optimized 3-dimensional conformal radiation (3-D), intensity-modulated radiation (IMRT), and single-field uniform dose (SFUD) scanning proton plans for each CTV. Mixed models regression was used to compare plans for bowel and rectal volumes exposed to 35% (V 35% ), 65% (V 65% ), and 95% (V 95% ) of the prescribed dose. For any given treatment modality, treating the larger CTV-comprehensive volume compared with treating only the CTV-pelvic sidewall nodes significantly increased rectal dose (V 35% rectum , V 65% rectum , and V 95% rectum ; p < 0.001 for all comparisons), but it did not produce significant differences in bowel dose (V 95% bowel , V 65% bowel , or V 35% bowel ). The 3-D plans, compared with both the IMRT and the SFUD plans, had a significantly greater V 65% bowel and V 95% bowel for each proposed CTV ( p < 0.001 for all comparisons). The effect of treatment modality on rectal dosimetry differed by CTV, but it generally favored the IMRT and the SFUD plans over the 3-D plans. Comparison of the IMRT plan vs the SFUD plan yielded mixed results with no consistent advantage for the SFUD plan over the IMRT plan. Targeting a CTV that spares the cystectomy bed and presacral region may marginally improve rectal toxicity but would not be expected to improve the bowel toxicity associated with any given modality of adjuvant radiation. Using the IMRT or the SFUD plans instead of the 3-D conformal plan may improve both bowel and rectal toxicity. [ABSTRACT FROM AUTHOR]

Purpose: To inform radiation treatment planning for clinically staged, node-negative bladder cancer patients by identifying clinical factors associated with the presence and location of occult pathologic pelvic lymph nodes. Methods and Materials: The records of patients with clinically staged T1-T4N0 urothelial carcinoma of the bladder undergoing radical cystectomy and pelvic lymphadenectomy at a single institution were reviewed. Logistic regression was used to evaluate associations between preoperative clinical variables and occult pathologic pelvic or common iliac lymph nodes. Percentages of patient with involved lymph node regions entirely encompassed within whole bladder (perivesicular nodal region), small pelvic (perivesicular, obturator, internal iliac, and external iliac nodal regions), and extended pelvic clinical target volume (CTV) (small pelvic CTV plus common iliac regions) were calculated. Results: Among 315 eligible patients, 81 (26%) were found to have involved pelvic lymph nodes at the time of surgery, with 38 (12%) having involved common iliac lymph nodes. Risk of occult pathologically involved lymph nodes did not vary with clinical T stage. On multivariate analysis, the presence of lymphovascular invasion (LVI) on preoperative biopsy was significantly associated with occult pelvic nodal involvement (odds ratio 3.740, 95% confidence interval 1.865-7.499, P<.001) and marginally associated with occult common iliac nodal involvement (odds ratio 2.307, 95% confidence interval 0.978-5.441, P=.056). The percentages of patients with involved lymph node regions entirely encompassed by whole bladder, small pelvic, and extended pelvic CTVs varied with clinical risk factors, ranging from 85.4%, 95.1%, and 100% in non-muscle-invasive patients to 44.7%, 71.1%, and 94.8% in patients with muscle-invasive disease and biopsy LVI. Conclusions: Occult pelvic lymph node rates are substantial for all clinical subgroups, especially patients with LVI on biopsy. Extended coverage of pelvic lymph nodes up to the level of the common iliac nodes may be warranted in subsets of patients. [Copyright &y& Elsevier]

Purpose: Despite the extensive use of complementary and alternative medicine (CAM) among cancer patients, patient-physician communication regarding CAM therapies remains limited. This study quantified the extent of patient-physician communication about CAM and identified factors associated with its discussion in radiation therapy (RT) settings. Methods and Materials: We conducted a cross-sectional survey of 305 RT patients at an urban academic cancer center. Patients with different cancer types were recruited in their last week of RT. Participants self-reported their demographic characteristics, health status, CAM use, patient-physician communication regarding CAM, and rationale for/against discussing CAM therapies with physicians. Multivariate logistic regression was used to identify relationships between demographic/clinical variables and patients’ discussion of CAM with radiation oncologists. Results: Among the 305 participants, 133 (43.6%) reported using CAM, and only 37 (12.1%) reported discussing CAM therapies with their radiation oncologists. In multivariate analyses, female patients (adjusted odds ratio [AOR] 0.45, 95% confidence interval [CI] 0.21-0.98) and patients with full-time employment (AOR 0.32, 95% CI 0.12-0.81) were less likely to discuss CAM with their radiation oncologists. CAM users (AOR 4.28, 95% CI 1.93-9.53) were more likely to discuss CAM with their radiation oncologists than were non-CAM users. Conclusions: Despite the common use of CAM among oncology patients, discussions regarding these treatments occur rarely in the RT setting, particularly among female and full-time employed patients. Clinicians and patients should incorporate discussions of CAM to guide its appropriate use and to maximize possible benefit while minimizing potential harm. [ABSTRACT FROM AUTHOR]

Purpose: There is strong interest in partial-bladder radiation whether as a boost or definitive therapy to limit long-term toxicity. It is unclear that a standard preoperative examination can accurately identify all sites of disease within the bladder. The purpose of this study was to determine the correlation between preoperative localization of bladder tumors with postoperative findings to facilitate partial-bladder radiation techniques when appropriate. Methods and Materials: We examined patients with clinically staged T1-T4 invasive transitional cell carcinoma (TCC) or TCC with variant histology with no history of radiation or partial cystectomy undergoing radical cystectomy. Patients were scored as “under-detected” if a bladder site was involved with invasive disease (≥T1) at the time of cystectomy, but not identified preoperatively. Patients were additionally scored as “widely under-detected” if they had postoperative lesions that were not identified preoperatively in a given site, nor in any adjacent site. Rates of under-detected and widely under-detected lesions, as well as univariate and multivariate association between clinical variables and under-detection, were evaluated using logistic regression. Results: Among 222 patients, 96% (213/222) had at least 1 area of discordance. Fifty-eight percent of patients were under-detected in at least 1 location, whereas 12% were widely under-detected. Among 24 patients with a single site of disease on preoperative evaluation, 21/24 (88%) had at least 1 under-detected lesion and 14/24 (58%) were widely under-detected. On multivariate analysis, only solitary site of preoperative disease was associated with increased levels of under-detection of invasive disease (OR = 4.161, 95% CI, 1.368-12.657). Conclusion: Our study shows a stark discordance between preoperative and postoperative localization of bladder tumors. From a clinical perspective, incomplete localization of all sites of disease within the bladder may lead to marginal misses when a partial-bladder technique is used. [Copyright &y& Elsevier]

Purpose: Local-regional failures (LFs) after cystectomy with or without chemotherapy are common in locally advanced disease. Adjuvant radiation therapy (RT) could reduce LFs, but toxicity has discouraged its use. Modern RT techniques with improved normal tissue sparing have rekindled interest but require knowledge of pelvic failure patterns to design treatment volumes. Methods and Materials: Five-year LF rates after radical cystectomy plus pelvic node dissection with or without chemotherapy were determined for 8 pelvic sites among 442 urothelial bladder carcinoma patients. The impact of pathologic stage, margin status, nodal involvement, and extent of node dissection on failure patterns was assessed using competing risk analysis. We calculated the percentage of patients whose sites of LF would have been completely encompassed within various hypothetical clinical target volumes (CTVs) for postoperative radiation. Results: Compared with stage ≤pT2, stage ≥pT3 patients had higher 5-year LF rates in virtually all pelvic sites. Among stage ≥pT3 patients, margin status significantly altered the failure pattern whereas extent of node dissection and nodal positivity did not. In stage ≥pT3 patients with negative margins, failure occurred predominantly in the iliac/obturator nodes and uncommonly in the cystectomy bed and/or presacral nodes. Of these patients in whom failure subsequently occurred, 76% would have had all LF sites encompassed within CTVs covering only the iliac/obturator nodes. In stage ≥pT3 with positive margins, cystectomy bed and/or presacral nodal failures increased significantly. Only 57% of such patients had all LF sites within CTVs limited to the iliac/obturator nodes, but including the cystectomy bed and presacral nodes in the CTV when margins were positive increased the percentage of LFs encompassed to 91%. Conclusions: Patterns of failure within the pelvis are summarized to facilitate design of adjuvant RT protocols. These data suggest that RT should target at least the iliac/obturator nodes in stage ≥pT3 with negative margins; coverage of the presacral nodes and cystectomy bed may be necessary for stage ≥pT3 with positive margins. [Copyright &y& Elsevier]

Purpose: The addition of androgen deprivation therapy (ADT) to definitive external beam radiation therapy (RT) improves outcomes in higher-risk prostate cancer patients. However, the benefit of ADT with salvage RT in post-prostatectomy patients is not clearly established. Our study compares biochemical outcomes in post-prostatectomy patients who received salvage RT with or without concurrent ADT. Methods and Materials: Of nearly 2,000 post-prostatectomy patients, we reviewed the medical records of 191 patients who received salvage RT at the University of Pennsylvania between 1987 and 2007. Follow-up data were obtained by chart review and electronic polling of the institutional laboratory database and Social Security Death Index. Biochemical failure after salvage RT was defined as a prostate-specific antigen of 2.0 ng/mL above the post-RT nadir or the initiation of ADT after completion of salvage RT. Results: One hundred twenty-nine patients received salvage RT alone, and 62 patients received combined ADT and salvage RT. Median follow-up was 5.4 years. Patients who received combined ADT and salvage RT were younger, had higher pathologic Gleason scores, and higher rates of seminal vesicle invasion, lymph node involvement, and pelvic nodal irradiation compared with patients who received salvage RT alone. Patients who received combined therapy had improved biochemical progression-free survival (bPFS) compared with patients who received RT alone (p = 0.048). For patients with pathologic Gleason scores ≤7, combined RT and ADT resulted in significantly improved bPFS compared to RT alone (p = 0.013). Conclusions: These results suggest that initiating ADT during salvage RT in the post-prostatectomy setting may improve bPFS compared with salvage RT alone. However, prospective randomized data are necessary to definitively determine whether hormonal manipulation should be used with salvage RT. Furthermore, the optimal nature and duration of ADT and the patient subgroups in which ADT could provide the most benefit remain open questions. [Copyright &y& Elsevier]

Purpose: The present study was performed to compare outcomes after breast conservation treatment with iridium-192 implant boost vs. electron boost. Methods and Materials: From 1977 to 1983, 141 patients were treated with whole breast radiotherapy followed by iridium-192 boost after breast-conserving surgery. They were matched 1:1 to patients treated with electron boost. Outcome measures included survival, local recurrence, cosmesis, and complications. Results: Median follow-up was 16.7 and 12.6 years for the implant vs. electron groups (p < 0.001). Rates of local recurrence, freedom from distant metastases, and overall survival at 10/20 years did not differ between the groups, nor did patterns of first failure. Patients in the electron group were more likely to have excellent/good cosmesis than those in the implant group 1 year after radiotherapy (p = 0.014); this trend continued through 10 years but did not reach statistical significance at years 5/10. Complication rates were similar, although patients receiving electron boost seemed less likely to develop breast fibrosis than did those receiving implant boost (23/141 vs. 58/141, respectively, incidence rate ratio 0.7, p = 0.17). Conclusions: Twenty-year data demonstrate no difference in rates of local recurrence, freedom from distant metastases, overall survival, or patterns of failure between groups treated with these two well-described radiotherapy boost techniques. Better cosmesis was observed in the electron group 1 year after radiotherapy, with a trend continuing for 10 years. The incidence of complications was similar between the groups, with a trend toward increased fibrosis in patients receiving implant boost. [ABSTRACT FROM AUTHOR]

Purpose: To assess whether whole-pelvis (WP) intensity-modulated radiation therapy (IMRT) is associated with increased toxicity compared with prostate-only (PO) IMRT. Methods and Materials: We retrospectively analyzed all patients with prostate cancer undergoing definitive IMRT to 79.2 Gy with concurrent androgen deprivation at our institution from November 2005 to May 2007 with a minimum follow-up of 12 months. Thirty patients received initial WP IMRT to 45 Gy in 1.8-Gy fractions, and thirty patients received PO IMRT. Study patients underwent computed tomography simulation and treatment planning by use of predefined dose constraints. Bladder and rectal dose–volume histograms, maximum genitourinary (GU) and gastrointestinal (GI) Radiation Therapy Oncology Group toxicity grade, and late Grade 2 or greater toxicity-free survival curves were compared between the two groups by use of the Student t test, Fisher exact test, and Kaplan-Meier curve, respectively. Results: Bladder minimum dose, mean dose, median dose, volume receiving 5 Gy, volume receiving 20 Gy, volume receiving 40 Gy, and volume receiving 45 Gy and rectal minimum dose, median dose, and volume receiving 20 Gy were significantly increased in the WP group (all p values < 0.01). Maximum acute GI toxicity was limited to Grade 2 and was significantly increased in the WP group at 50% vs. 13% the PO group (p = 0.006). With a median follow-up of 24 months (range, 12–35 months), there was no difference in late GI toxicity (p = 0.884) or in acute or late GU toxicity. Conclusions: Despite dosimetric differences in the volume of bowel, bladder, and rectum irradiated in the low-dose and median-dose regions, WP IMRT results only in a clinically significant increase in acute GI toxicity, in comparison to PO IMRT, with no difference in GU or late GI toxicity. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate dosimetric consequences of daily isocenter correction during prostate cancer radiation therapy using the Calypso 4D localization system. Methods and Materials: Data were analyzed from 28 patients with electromagnetic transponders implanted in their prostates for daily target localization and tracking. Treatment planning isocenters were recorded based on the values of the vertical, longitudinal, and lateral axes. Isocenter location obtained via alignment with skin tattoos was compared with that obtained via the electromagnetic localization system. Daily isocenter shifts, based on the isocenter location differences between the two alignment methods in each spatial axis, were calculated for each patient over their entire course. The mean isocenter shifts were used to determine dosimetric consequences of treatment based on skin tattoo alignments alone. Results: The mean ⩲ SD of the percentages of treatment days with shifts beyond ⩲ 0.5 cm for vertical, longitudinal and lateral shifts were 62% ⩲ 28%, 35% ⩲ 26%, and 38% ⩲21%, respectively. If daily electromagnetic localization was not used, the excess in prescribed dose delivered to 70% of the rectum was 10 Gy and the deficit in prescribed dose delivered to 95% of the planning target volume was 10 Gy. The mean isocenter shift was not associated with the volumes of the prostate, rectum, or bladder, or with patient body mass index. Conclusions: Daily isocenter localization can reduce the treatment dose to the rectum. Correcting for this variability could lead to improved dose delivery, reduced side effects, and potentially improved treatment outcomes. [Copyright &y& Elsevier]