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At least 811 records · Page 45
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

A Comparison of the Prognostic Value of Early PSA Test-Based Variables Following External Beam Radiotherapy, With or Without Preceding Androgen Deprivation: Analysis of Data From the TROG 96.01 Randomized Trial

Purpose: We sought to compare the prognostic value of early prostate-specific antigen (PSA) test-based variables for the 802 eligible patients treated in the Trans-Tasman Radiation Oncology Group 96.01 randomized trial. Methods and Materials: Patients in this trial had T2b, T2c, T3, and T4 N0 prostate cancer and were randomized to 0, 3, or 6 months of neoadjuvant androgen deprivation therapy (NADT) prior to and during radiation treatment at 66 Gy to the prostate and seminal vesicles. The early PSA test-based variables evaluated were the pretreatment initial PSA (iPSA) value, PSA values at 2 and 4 months into NADT, the PSA nadir (nPSA) value after radiation in all patients, and PSA response signatures in men receiving radiation. Comparisons of endpoints were made using Cox models of local progression-free survival, distant failure-free survival, biochemical failure-free survival, and prostate cancer-specific survival. Results: The nPSA value was a powerful predictor of all endpoints regardless of whether NADT was given before radiation. PSA response signatures also predicted all endpoints in men treated by radiation alone. iPSA and PSA results at 2 and 4 months into NADT predicted biochemical failure-free survival but not any of the clinical endpoints. nPSA values correlated with those of iPSA, Gleason grade, and T stage and were significantly higher in men receiving radiation alone than in those receiving NADT. Conclusions: The postradiation nPSA value is the strongest prognostic indicator of all early PSA-based variables. However, its use as a surrogate endpoint needs to take into account its dependence on pretreatment variables and treatment method.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Radiation Therapy for Pilocytic Astrocytomas of Childhood

Purpose: Though radiation therapy is generally considered the most effective treatment for unresectable pilocytic astrocytomas in children, there are few data to support this claim. To examine the efficacy of radiation therapy for pediatric pilocytic astrocytomas, we retrospectively reviewed the experience at our institution. Methods and Materials: Thirty-five patients 18 years old or younger with unresectable tumors and without evidence of neurofibromatosis have been treated since 1982. Patients were treated with local radiation fields to a median dose of 54 Gy. Six patients were treated with radiosurgery to a median dose of 15.5 Gy. Five patients were treated with initial chemotherapy and irradiated after progression. Results: All patients were alive after a median follow-up of 5.0 years. However, progression-free survival was 68.7%. None of 11 infratentorial tumors progressed compared with 6 of 20 supratentorial tumors. A trend toward improved progression-free survival was seen with radiosurgery (80%) compared with external beam alone (66%), but this difference did not reach statistical significance. Eight of the 9 patients progressing after therapy did so within the irradiated volume. Conclusions: Although the survival of these children is excellent, almost one third of patients have progressive disease after definitive radiotherapy. Improvements in tumor control are needed in this patient population, and the optimal therapy has not been fully defined. Prospective trials comparing initial chemotherapy to radiation therapy are warranted.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Outcomes in Black Patients With Early Breast Cancer Treated With Breast Conservation Therapy

Background: The race-specific impact of prognostic variables for early breast cancer is unknown for black patients undergoing breast conservation. Methods and Materials: This was a retrospective study of 1,231 consecutive patients {>=}40 years of age with Stage I-II invasive breast cancer treated with lumpectomy and radiation therapy at the University of Chicago Hospitals and affiliates between 1986 and 2004. Patients were classified as either black or nonblack. Cox proportional hazards regression was used to model the effects of known prognostic factors and interactions with race. Results: Median follow-up for surviving patients was 82 months. Thirty-four percent of patients were black, and 66% were nonblack (Caucasian, Hispanic, and Asian). Black patients had a poorer 10-year overall survival (64.6% vs. 80.8%; adjusted hazard ratio [HR], 1.59; 95% confidence interval [CI], 1.23-2.06) and 10-year disease-free survival (58.1% vs. 75.4%; HR 1.49; 95% CI, 1.18-1.89) compared with nonblack patients. Tumor sizes were similar between nonblack and black patients with mammographically detected tumors (1.29 cm vs. 1.20 cm, p = 0.20, respectively). Tumor size was significantly associated with overall survival (HR 1.48; 95% CI, 1.12-1.96) in black patients with mammographically detected tumors but not in nonblack patients (HR 1.09; 95% CI, 0.78-1.53), suggesting that survival in black patients depends more strongly on tumor size in this subgroup. Tests for race-size method of detection interactions were statistically significant for overall survival (p = 0.049), locoregional control (p = 0.036), and distant control (p = 0.032) and borderline significant for disease-free survival (p = 0.067). Conclusion: Despite detection at comparable sizes, the prognostic effect of tumor size in patients with mammographically detected tumors is greater for black than in nonblack patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Adjuvant Chemoradiation for Gastric Cancer Using Epirubicin, Cisplatin, and 5-Fluorouracil Before and After Three-Dimensional Conformal Radiotherapy With Concurrent Infusional 5-Fluorouracil: A Multicenter Study of the Trans-Tasman Radiation Oncology Group

Purpose: The INT0116 study has established postoperative chemoradiotherapy as the standard of care for completely resected gastric adenocarcinoma. However, the optimal chemoradiation regimen remains to be defined. We conducted a prospective, multicenter study to evaluate an alternative chemoradiation regimen that combines more current systemic treatment with modern techniques of radiotherapy delivery. Methods and Materials: Patients with adenocarcinoma of the stomach who had undergone an R0 resection were eligible. Adjuvant therapy consisted of one cycle of epirubicin, cisplatin, and 5-FU (ECF), followed by radiotherapy with concurrent infusional 5-FU, and then two additional cycles of ECF. Radiotherapy was delivered using precisely defined, multiple-field, three-dimensional conformal techniques. Results: A total of 54 assessable patients were enrolled from 19 institutions. The proportion of patients commencing Cycles 1, 2, and 3 of ECF chemotherapy were 100%, 81%, and 67% respectively. In all, 94% of patients who received radiotherapy completed treatment as planned. Grade 3/4 neutropenia occurred in 66% of patients with 7.4% developing febrile neutropenia. Most neutropenic episodes (83%) occurred in the post-radiotherapy period during cycles 2 and 3 of ECF. Grade 3/4 gastrointestinal toxicity occurred in 28% of patients. In all, 35% of radiotherapy treatment plans contained protocol deviations that were satisfactorily amended before commencement of treatment. At median follow-up of 36 months, the 3-year overall survival rate was estimated at 61.6%. Conclusions: This adjuvant regimen using ECF before and after three-dimensional conformal chemoradiation is feasible and can be safely delivered in a cooperative group setting. A regimen similar to this is currently being compared with the INT0116 regimen in a National Cancer Institute-sponsored, randomized Phase III trial.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Feasibility of Economic Analysis of Radiation Therapy Oncology Group (RTOG) 91-11 Using Medicare Data

Purpose: The specific aim of this analysis was to evaluate the feasibility of performing a cost-effectiveness analysis using Medicare data from patients treated on a randomized Phase III clinical trial. Methods and Materials: Cost data included Medicare Part A and Part B costs from all providers-inpatient, outpatient, skilled nursing facility, home health, hospice, and physicians-and were obtained from the Centers for Medicare and Medicaid Services for patients eligible for Medicare, treated on Radiation Therapy Oncology Group (RTOG) 9111 between 1992 and 1996. The 47-month expected discounted (annual discount rate of 3%) cost for each arm of the trial was calculated in 1996 dollars, with Kaplan-Meier sampling average estimates of survival probabilities for each month and mean monthly costs. Overall and disease-free survival was also discounted 3%/year. The analysis was performed from a payer's perspective. Incremental cost-effectiveness ratios were calculated comparing the chemotherapy arms to the radiation alone arm. Results: Of the 547 patients entered, Medicare cost data and clinical outcomes were available for 66 patients. Reasons for exclusion included no RTOG follow-up, Medicare HMO enrollment, no Medicare claims since trial entry, and trial entry after 1996. Differences existed between groups in tumor characteristics, toxicity, and survival, all which could affect resource utilization. Conclusions: Although we were able to test the methodology of economic analysis alongside a clinical trial using Medicare data, the results may be difficult to translate to the entire trial population because of non-random missing data. Methods to improve Medicare data capture and matching to clinical trial samples are required.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Uveal Melanoma Recurrence After Fractionated Proton Beam Therapy: Comparison of Survival in Patients Treated With Reirradiation or With Enucleation

Purpose: To retrospectively compare survival in recurrent uveal melanoma, between patients treated by enucleation or by a second course of fractionated proton beam therapy (PBT). Methods and Materials: Tumor recurrence was documented in 73 patients treated with PBT for uveal melanoma. Of the patients, 31 received a second course of PBT and 42 underwent enucleation. The mean patient age was 56 and 61 years for those undergoing enucleation and those undergoing reirradiation, respectively. Both primary and recurrent tumors were larger in patients undergoing enucleation. Tumor location and the presence or absence of ciliary body involvement did not differ significantly between the groups. The median follow-up after enucleation and after re-treatment was 79 and 59 months, respectively. Cumulative rates of outcomes and differences in rates between the reirradiated and enucleation groups were calculated by the Cox proportional hazards model and the log-rank test, respectively. Results: The median survival duration in the enucleated and reirradiated groups was 42 and 90 months, respectively. The median time free of metastases was 38 months in enucleated patients and 97 months in reirradiated patients. At 5 years after enucleation and after reirradiation, the probability of overall survival was 36% and 63%, respectively (p = 0.040, log-rank test); the probability of freedom from metastases was 31% and 66%, respectively (p = 0.028, log-rank test). These differences persisted after adjustment for recurrent tumor largest diameter and volume at the time of reirradiation or enucleation. Conclusions: This retrospective analysis suggests that survival in reirradiated patients is not compromised by administration of a second course of PBT for recurrent uveal melanoma.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Treatment Results of PDR Brachytherapy Combined With External Beam Radiotherapy in 106 Patients With Intermediate- to High-Risk Prostate Cancer

Purpose: To evaluate treatment outcome of pulsed dose-rate brachytherapy (PDR) combined with external-beam radiotherapy (EBRT) for the treatment of prostate cancer. Methods and Materials: Between 2002 and 2007, 106 patients were treated by EBRT combined with PDR and followed prospectively. Two, 38, and 66 patients were classified as low-, intermediate-, and high-risk disease respectively according to the National Comprehensive Cancer Network criteria. EBRT dose was 46 Gy in 2.0-Gy fractions. PDR dose was increased stepwise from 24.96 to 28.80 Gy. Biochemical disease free survival and overall survival were determined by the Kaplan-Meier method. Cumulative incidence of late gastrointestinal (GI) and genitourinary (GU) toxicity were scored, according to the Common Terminology Criteria for Adverse Events. Results: The 3- and 5-year biochemical nonevidence of disease (bNED) were 92.8% (95% confidence interval [CI], 87.1-98.5) and 89.5% (95% CI, 85.2-93.8), respectively. Overall survival at 3 and 5 years was 99% (95% CI, 96-100) and 96% (95% CI, 90-100), respectively. The 3- and 5-year Grade 2 GI toxicity was 5.3% (95% CI, 0-10.6) and 12.0% (95% CI, 1.4-22.6), respectively. No Grade 3 or higher GI toxicity was observed. The 3- and 5-year Grade 2 or higher GU toxicity was 18.7% (95% CI, 10.3-27.1) and 26.9% (95% CI, 15.1-38.7), respectively. Conclusion: Results on tumor control and late toxicity of EBRT combined with PDR are good and comparable to results obtained with EBRT combined with high-dose-rate brachytherapy for the treatment of prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Estimating the Need for Radiotherapy for Patients With Prostate, Breast, and Lung Cancers: Verification of Model Estimates of Need With Radiotherapy Utilization Data From British Columbia

Purpose: Estimates of the need for radiotherapy (RT) using different methods (criterion based benchmarking [CBB]and the Canadian [C-EBEST]and Australian [A-EBEST]epidemiologically based estimates) exist for various cancer sites. We compared these model estimates to actual RT rates for lung, breast, and prostate cancers in British Columbia (BC). Methods and Materials: All cases of lung, breast, and prostate cancers in BC from 1997 to 2004 and all patients receiving RT within 1 year (RT{sub 1Y}) and within 5 years (RT{sub 5Y}) of diagnosis were identified. The RT{sub 1Y} and RT{sub 5Y} proportions in health regions with a cancer center for the most recent year were then calculated. RT rates were compared with CBB and EBEST estimates of RT needs. Variation was assessed by time and region. Results: The RT{sub 1Y} in regions with a cancer center for lung, breast, and prostate cancers were 51%, 58%, and 33% compared with 45%, 57%, and 32% for C-EBEST and 41%, 61%, and 37% for CBB models. The RT{sub 5Y} rates in regions with a cancer center for lung, breast, and prostate cancers were 59%, 61%, and 40% compared with 61%, 66%, and 61% for C-EBEST and 75%, 83%, and 60% for A-EBEST models. The RT{sub 1Y} rates increased for breast and prostate cancers. Conclusions: C-EBEST and CBB model estimates are closer to the actual RT rates than the A-EBEST estimates. Application of these model estimates by health care decision makers should be undertaken with an understanding of the methods used and the assumptions on which they were based.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Does Hormone Therapy Reduce Disease Recurrence in Prostate Cancer Patients Receiving Dose-Escalated Radiation Therapy? An Analysis of Radiation Therapy Oncology Group 94-06

Purpose: The purpose of this study was to evaluate the effect on freedom from biochemical failure (bNED) or disease-free survival (DFS) by adding hormone therapy (HT) to dose-escalated radiation therapy (HDRT). Methods and Materials: We used 883 analyzable prostate cancer patients who enrolled on Radiation Therapy Oncology Group (RTOG) 94-06, a Phase I/II dose escalation trial, and whose mean planning target volume dose exceeded 73.8 Gy (mean, 78.5 Gy; maximum, 84.3 Gy). We defined biochemical failure according to the Phoenix definition. Results: A total of 259 men started HT 2 to 3 months before HDRT, but not longer than 6 months, and 66 men with high-risk prostate cancer received HT for a longer duration. At 5 years, the biochemical failure rates after HDRT alone were 12%, 18%, and 29% for low-, intermediate-, and high-risk patients, respectively (p < 0.0001). Cox proportional hazards regression analysis adjusted for covariates revealed that pretreatment PSA level was a significant factor, whereas risk group, Gleason score, T-stage, and age were not. When the patients were stratified by risk groups, the Cox proportion hazards regression model (after adjusting for pretreatment PSA, biopsy Gleason score, and T stage) did not reveal a significant effect on bNED or DFS by adding HT to HDRT Conclusion: The addition of HT did not significantly improve bNED survival or DFS in all prostate cancer patients receiving HDRT, but did approach significance in high-risk patient subgroup. The result of this study is hypothesis generating and requires testing in a prospective randomized trial.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Matched Survival Analysis in Patients With Locoregionally Advanced Resectable Oropharyngeal Carcinoma: Platinum-Based Induction and Concurrent Chemoradiotherapy Versus Primary Surgical Resection

Purpose: The outcome of a prospective case series of 47 patients with newly diagnosed resectable locoregionally advanced oropharyngeal squamous cell carcinoma treated with platinum-based induction-concurrent chemoradiotherapy (IC/CCRT) was compared with the outcome of 47 matched historical control patients treated with surgery and postoperative RT. Methods and Materials: A total of 47 control patients with locoregionally advanced oropharyngeal squamous cell carcinoma were identified from review of a prospectively compiled comprehensive computerized head-and-neck cancer database and were matched with a prospective case series of patients undergoing IC/CCRT by disease stage, nodal status, gender, and age ({+-}5 years). The IC/CCRT regimen consisted of one cycle of induction chemotherapy followed by conventionally fractionated RT to a total dose of 66-70 Gy concomitantly with two cycles of chemotherapy. Each cycle of chemotherapy consisted of cisplatinum, 100 mg/m{sup 2}, and a continuous infusion of 5-fluorouracil, 1,000 mg/m{sup 2}/d for 5 days. The survival analysis was performed using Kaplan-Meier estimates. Matched-pair survival was compared using the Cox proportional hazards model. Results: No significant difference was found in the overall survival or progression-free survival rates between the two groups. The matched analysis of survival did not show a statistically significant greater hazard ratio for overall death (hazard ratio, 1.35; 95% confidence interval, 0.65-2.80; p = .415) or progression (hazard ratio, 1.44; 95% confidence interval, 0.72-2.87; p = .301) for patients undergoing IC/CCRT. Conclusion: Although the sample size was small and not randomized, this matched-pair comparison between a prospective case series and a historical cohort treated at the same institution showed that the efficacy of IC/CCRT with salvage surgery is as good as primary surgical resection and postoperative RT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Local Therapy for Rhabdomyosarcoma of the Hands and Feet: Is Amputation Necessary? A Report From the Children's Oncology Group

Purpose: To evaluate the outcome of children with rhabdomyosarcoma (RMS) of the hand or foot treated with surgery and/or local radiotherapy (RT). Methods and Materials: Forty-eight patients with nonmetastatic RMS of the hand or foot were enrolled on Intergroup Rhabdomyosarcoma Study III, IV-Pilot, and IV. Patients received multiagent chemotherapy with surgery and/or RT. Twenty-four patients (50%) underwent surgery without local RT, of whom 4 had complete resection and 20 had an amputation. The remaining 24 patients (50%) underwent local RT, of whom 2 required RT for microscopic residual disease after prior amputation. Median follow-up for surviving patients was 9.7 years. Results: Actuarial 10-year local control was 100%; 10-year event-free survival and overall survival rates were 62% and 63%, respectively. Poor prognostic factors for recurrence included gross residual (Group III) disease and nodal involvement (p = 0.01 and 0.05, respectively). More patients in the RT group had alveolar histology, Group III disease, and nodal involvement, as compared with the surgery group. There was no difference in 10-year event-free survival (57% vs. 66%) or overall survival (63% vs. 63%) between patients who underwent surgery or local RT. Among relapsing patients, there were no long-term survivors. No secondary malignancies have been observed. Conclusions: Despite having high-risk features, patients treated with local RT achieved excellent local control. Complete surgical resection without amputation is difficult to achieve in the hand or foot. Therefore, we recommend either definitive RT or surgical resection that maintains form and function as primary local therapy rather than amputation in patients with hand or foot RMS.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Residual Prostate Cancer in Patients Treated With Endocrine Therapy With or Without Radical Radiotherapy: A Side Study of the SPCG-7 Randomized Trial

Purpose: The Scandinavian Prostate Cancer Group-7 randomized trial demonstrated a survival benefit of combined endocrine therapy and external-beam radiotherapy over endocrine therapy alone in patients with high-risk prostate cancer. In a subset of the study population, the incidence and clinical implications of residual prostate cancer in posttreatment prostate biopsy specimens was evaluated. Methods and Materials: Biopsy specimens were obtained from 120 of 875 men in the Scandinavian Prostate Cancer Group-7 study. Results: Biopsies were performed at median of 45 months follow-up. In 63 patients receiving endocrine treatment only and 57 patients receiving combined treatment, residual cancer was found in 66% (n = 41) and 22% (n = 12), respectively (p < 0.0001). The vast majority of residual tumors were poorly differentiated (Gleason score {>=}8). Endocrine therapy alone was predictive of residual prostate cancer: odds ratio 7.49 (3.18-17.7), p < 0.0001. In patients with positive vs. negative biopsy the incidences of clinical events were as follows: biochemical recurrence 74% vs. 27% (p < 0.0001), local progression 26% vs. 4.7% (p = 0.002), distant recurrence 17% vs. 9.4% (p = 0.27), clinical recurrence 36% vs. 13% (p = 0.006), cancer-specific death 19% vs. 9.7% (p = 0.025). In multivariable analysis, biochemical recurrence was significantly associated with residual cancer: hazard ratio 2.69 (1.45-4.99), p = 0.002, and endocrine therapy alone hazard ratio 3.45 (1.80-6.62), p < 0.0001. Conclusions: Radiotherapy combined with hormones improved local tumor control in comparison with endocrine therapy alone. Residual prostate cancer was significantly associated with serum prostate-specific antigen recurrence, local tumor progression, clinical recurrence, and cancer-specific death in univariable analysis. Residual cancer was predictive of prostate-specific antigen recurrence in multivariable analysis.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Postoperative Radiotherapy for Lung Cancer: Improvement in Locoregional Control Using Three-Dimensional Compared With Two-Dimensional Technique

Purpose: To determine whether lung cancer patients treated with three-dimensional (3D) postoperative radiotherapy (PORT) have more favorable outcomes than those treated with two-dimensional (2D) PORT. Patients and Methods: We retrospectively analyzed the charts of 153 lung cancer patients who underwent PORT with curative intent at our center between 1995 and 2007. The patients were grouped according to the RT technique; 66 patients were in the 2D group and 87 in the 3D group. The outcomes included locoregional control, survival, and secondary effects. All patients were treated using a linear accelerator at a total dose of approximately 50 Gy and 2 Gy/fraction. A few patients (21%) also received chemotherapy. Most tumors were in the advanced stage, either Stage II (30%) or Stage III (65%). The main clinical indications for PORT were positive resection margins (23%) and Stage pN2 (52%) and pN1 (22%). The patient characteristics were comparable in both groups. Results: Kaplan-Meier analysis showed that the 3D technique significantly improved the locoregional control rate at 5 years compared with the 2D technique (81% vs. 56%, p = .007 [Cox]). The 2D technique was associated with a more than twofold increased risk of locoregional recurrence (hazard ratio, 2.7; 95% confidence interval, 1.3-5.5; p = .006). The overall survival rate did not differ at 5 years (38% vs. 20%, p = .3 [Cox]). The toxicities were also similar and acceptable in both groups. Conclusion: The 3D technique for conformal PORT for lung cancer improved the locoregional control rates of patients compared with the 2D technique.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Monotherapeutic High-Dose-Rate Brachytherapy for Prostate Cancer: Five-Year Results of an Extreme Hypofractionation Regimen With 54 Gy in Nine Fractions

Purpose: To evaluate an extreme hypofractionation regimen with 54 Gy in nine fractions provided by high-dose-rate (HDR) brachytherapy as monotherapy for prostate cancer by reporting 5-year clinical results. Methods and Materials: Between 1996 and 2005, 112 patients with localized prostate cancer were treated with HDR brachytherapy without external beam radiotherapy. Of the 112 patients, 15 were considered low risk, 29 intermediate risk, and 68 as high risk. The prescribed dose was uniformly 54 Gy in nine fractions within 5 days. Of the 112 patients, 94 also received hormonal therapy. The median follow-up time was 5.4 years. Results: All the patients safely completed the treatment regimen. The 5-year prostate-specific antigen (PSA) failure-free, local control, disease-free survival, and overall survival rate was 83%, 97%, 87%, and 96%, respectively. The 5-year PSA failure-free rate for low-, intermediate-, and high-risk patients was 85% (95% confidence interval, 66-100%), 93% (95% confidence interval, 83-100%), and 79% (95% confidence interval, 69-89%), respectively. The significant prognostic factors for PSA failure were the initial PSA level (p = .029) and younger age (p = .019). The maximal toxicities observed were Grade 3 using the Common Terminology Criteria for Adverse Events, version 3.0, for both acute and late toxicity (6 and 3 patients had acute and late Grade 3 toxicity, respectively). Late Grade 2 toxicity was observed in 13 patients. Conclusion: Monotherapeutic HDR brachytherapy with an extreme hypofractionation regimen of 54 Gy in nine fractions associated with hormonal therapy was feasible, and its toxicity was acceptable. The interim tumor control rate at a median 5.4 years was promising, even for patients with locally advanced disease. This dose-fractionation scheme might be referred to by other terms, such as stereotactic body radiotherapy. Studies with longer follow-up periods and from multiple institutions are needed to confirm the efficacy of this novel approach.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Prospective Trial of High-Dose Reirradiation Using Daily Image Guidance With Intensity-Modulated Radiotherapy for Recurrent and Second Primary Head-and-Neck Cancer

Purpose: To report a single-institutional experience using intensity-modulated radiotherapy with daily image-guided radiotherapy for the reirradiation of recurrent and second cancers of the head and neck. Methods and Materials: Twenty-one consecutive patients were prospectively treated with intensity-modulated radiotherapy from February 2006 to March 2009 to a median dose of 66 Gy (range, 60-70 Gy). None of these patients received concurrent chemotherapy. Daily helical megavoltage CT scans were obtained before each fraction as part of an image-guided radiotherapy registration protocol for patient alignment. Results: The 1- and 2-year estimates of in-field control were 72% and 65%, respectively. A total of 651 daily megavoltage CT scans were obtained. The mean systematic shift to account for interfraction motion was 1.38 {+-} 1.25 mm, 1.79 {+-} 1.45 mm, and 1.98 {+-} 1.75 mm for the medial-lateral, superior-inferior, and anterior-posterior directions, respectively. Pretreatment shifts of >3 mm occurred in 19% of setups in the medial-lateral, 27% in the superior-inferior, and 33% in the anterior-posterior directions, respectively. There were no treatment-related fatalities or hospitalizations. Complications included skin desquamation, odynophagia, otitis externa, keratitis, naso-lacrimal duct stenosis, and brachial plexopathy. Conclusions: Intensity-modulated radiotherapy with daily image guidance results in effective disease control with relatively low morbidity and should be considered for selected patients with recurrent and second primary cancers of the head and neck.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Greater Biopsy Core Number Is Associated With Improved Biochemical Control in Patients Treated With Permanent Prostate Brachytherapy

Purpose: Standard prostate biopsy schemes underestimate Gleason score in a significant percentage of cases. Extended biopsy improves diagnostic accuracy and provides more reliable prognostic information. In this study, we tested the hypothesis that greater biopsy core number should result in improved treatment outcome through better tailoring of therapy. Methods and Materials: From April 1995 to May 2006, 1,613 prostate cancer patients were treated with permanent brachytherapy. Patients were divided into five groups stratified by the number of prostate biopsy cores ({<=}6, 7-9, 10-12, 13-20, and >20 cores). Biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were evaluated as a function of core number. Results: The median patient age was 66 years, and the median preimplant prostate-specific antigen was 6.5 ng/mL. The overall 10-year bPFS, CSS, and OS were 95.6%, 98.3%, and 78.6%, respectively. When bPFS was analyzed as a function of core number, the 10-year bPFS for patients with >20, 13-20, 10-12, 7-9 and {<=}6 cores was 100%, 100%, 98.3%, 95.8%, and 93.0% (p < 0.001), respectively. When evaluated by treatment era (1995-2000 vs. 2001-2006), the number of biopsy cores remained a statistically significant predictor of bPFS. On multivariate analysis, the number of biopsy cores was predictive of bPFS but did not predict for CSS or OS. Conclusion: Greater biopsy core number was associated with a statistically significant improvement in bPFS. Comprehensive regional sampling of the prostate may enhance diagnostic accuracy compared to a standard biopsy scheme, resulting in better tailoring of therapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Intensity-Modulated Radiotherapy for Oral Cavity Squamous Cell Carcinoma: Patterns of Failure and Predictors of Local Control

Purpose: Few studies have evaluated the use of intensity-modulated radiotherapy (IMRT) for squamous cell carcinoma (SCC) of the oral cavity (OC). We report clinical outcomes and failure patterns for these patients. Methods and Materials: Between October 2002 and June 2009, 37 patients with newly diagnosed SCC of the OC underwent postoperative (30) or definitive (7) IMRT. Twenty-five patients (66%) received systemic therapy. The median follow-up was 38 months (range, 10-87 months). The median interval from surgery to RT was 5.9 weeks (range, 2.1-10.7 weeks). Results: Thirteen patients experienced local-regional failure at a median of 8.1 months (range, 2.4-31.9 months), and 2 additional patients experienced local recurrence between surgery and RT. Seven local failures occurred in-field (one with simultaneous nodal and distant disease) and two at the margin. Four regional failures occurred, two in-field and two out-of-field, one with synchronous metastases. Six patients experienced distant failure. The 3-year actuarial estimates of local control, local-regional control, freedom from distant metastasis, and overall survival were 67%, 53%, 81%, and 60% among postoperative patients, respectively, and 60%, 60%, 71%, and 57% among definitive patients. Four patients developed Grade {>=}2 chronic toxicity. Increased surgery to RT interval predicted for decreased LRC (p = 0.04). Conclusions: Local-regional control for SCC of the OC treated with IMRT with or without surgery remains unsatisfactory. Definitive and postoperative IMRT have favorable toxicity profiles. A surgery-to-RT interval of <6 weeks improves local-regional control. The predominant failure pattern was local, suggesting that both improvements in target delineation and radiosensitization and/or dose escalation are needed.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

10-Year Experience With I-125 Prostate Brachytherapy at the Princess Margaret Hospital: Results for 1,100 Patients

Purpose: To report outcomes for 1,111 men treated with iodine-125 brachytherapy (BT) at a single institution. Methods and Materials: A total of 1,111 men (median age, 63) were treated with iodine-125 prostate BT for low- or intermediate-risk prostate cancer between March 1999 and November 2008. Median prostate-specific antigen (PSA) level was 5.4 ng/ml (range, 0.9-26.1). T stage was T1c in 66% and T2 in 34% of patients. Gleason score was 6 in 90.1% and 7 or 8 in 9.9% of patients. Neoadjuvant hormonal therapy (2-6 months course) was used in 10.1% of patients and combined external radiotherapy (45 Gy) with BT (110 Gy) in 4.1% (n = 46) of patients. Univariate and multivariate Cox proportional hazards were used to determine predictors of failure. Results: Median follow-up was 42 months (range, 6-114), but for biochemical freedom from relapse, a minimum PSA test follow-up of 30 months was required (median 54; n = 776). There were 27 failures, yielding an actuarial 7-year disease-free survival rate of 95.2% (96 at risk beyond 84 months). All failures underwent repeat 12-core transrectal ultrasound -guided biopsies, confirming 8 local failures. On multivariate analysis, Gleason score was the only independent predictor of failure (p = 0.001; hazard ratio, 4.8 (1.9-12.4). Median International Prostate Symptom score from 12 to 108 months ranged between 3 and 9. Of the men reporting baseline potency, 82.8% retained satisfactory erectile function beyond 5 years. Conclusion: Iodine-125 prostate BT is a highly effective treatment option for favorable- and intermediate-risk prostate cancer and is associated with maintenance of good urinary and erectile functions.

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