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At least 1,693 records · Page 94
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Dose-Volume Histogram Parameters and Clinical Factors Associated With Pleural Effusion After Chemoradiotherapy in Esophageal Cancer Patients

Purpose: To investigate the dose-volume histogram parameters and clinical factors as predictors of pleural effusion in esophageal cancer patients treated with concurrent chemoradiotherapy (CRT). Methods and Materials: Forty-three esophageal cancer patients treated with definitive CRT from January 2001 to March 2007 were reviewed retrospectively on the basis of the following criteria: pathologically confirmed esophageal cancer, available computed tomography scan for treatment planning, 6-month follow-up after CRT, and radiation dose {>=}50 Gy. Exclusion criteria were lung metastasis, malignant pleural effusion, and surgery. Mean heart dose, mean total lung dose, and percentages of heart or total lung volume receiving {>=}10-60 Gy (Heart-V{sub 10} to V{sub 60} and Lung-V{sub 10} to V{sub 60}, respectively) were analyzed in relation to pleural effusion. Results: The median follow-up time was 26.9 months (range, 6.7-70.2) after CRT. Of the 43 patients, 15 (35%) developed pleural effusion. By univariate analysis, mean heart dose, Heart-V{sub 10} to V{sub 60}, and Lung-V{sub 50} to V{sub 60} were significantly associated with pleural effusion. Poor performance status, primary tumor of the distal esophagus, and age {>=}65 years were significantly related with pleural effusion. Multivariate analysis identified Heart-V{sub 50} as the strongest predictive factor for pleural effusion (p = 0.01). Patients with Heart-V{sub 50} <20%, 20%{<=} Heart-V{sub 50} <40%, and Heart-V{sub 50} {>=}40% had 6%, 44%, and 64% of pleural effusion, respectively (p < 0.01). Conclusion: Heart-V{sub 50} is a useful parameter for assessing the risk of pleural effusion and should be reduced to avoid pleural effusion.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

70 Gy Versus 80 Gy in Localized Prostate Cancer: 5-Year Results of GETUG 06 Randomized Trial;Prostate cancer; Dose escalation; Conformal radiotherapy; Randomized trial

Purpose: To perform a randomized trial comparing 70 and 80 Gy radiotherapy for prostate cancer. Patients and Methods: A total of 306 patients with localized prostate cancer were randomized. No androgen deprivation was allowed. The primary endpoint was biochemical relapse according to the modified 1997-American Society for Therapeutic Radiology and Oncology and Phoenix definitions. Toxicity was graded using the Radiation Therapy Oncology Group 1991 criteria and the late effects on normal tissues-subjective, objective, management, analytic scales (LENT-SOMA) scales. The patients' quality of life was scored using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire 30-item cancer-specific and 25-item prostate-specific modules. Results: The median follow-up was 61 months. According to the 1997-American Society for Therapeutic Radiology and Oncology definition, the 5-year biochemical relapse rate was 39% and 28% in the 70- and 80-Gy arms, respectively (p = .036). Using the Phoenix definition, the 5-year biochemical relapse rate was 32% and 23.5%, respectively (p = .09). The subgroup analysis showed a better biochemical outcome for the higher dose group with an initial prostate-specific antigen level >15 ng/mL. At the last follow-up date, 26 patients had died, 10 of their disease and none of toxicity, with no differences between the two arms. According to the Radiation Therapy Oncology Group scale, the Grade 2 or greater rectal toxicity rate was 14% and 19.5% for the 70- and 80-Gy arms (p = .22), respectively. The Grade 2 or greater urinary toxicity was 10% at 70 Gy and 17.5% at 80 Gy (p = .046). Similar results were observed using the LENT-SOMA scale. Bladder toxicity was more frequent at 80 Gy than at 70 Gy (p = .039). The quality-of-life questionnaire results before and 5 years after treatment were available for 103 patients with no differences found between the 70- and 80-Gy arms. Conclusion: High-dose radiotherapy provided a better 5-year biochemical outcome with slightly greater toxicity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Adoption of Preoperative Radiation Therapy for Rectal Cancer From 2000 to 2006: A Surveillance, Epidemiology, and End Results Patterns-of-Care Study

Purpose: The German rectal study determined that preoperative radiation therapy (RT) as a component of combined-modality therapy decreased local tumor recurrence, increased sphincter preservation, and decreased treatment toxicity compared with postoperative RT for rectal cancer. We evaluated the use of preoperative RT after the presentation of the landmark German rectal study results and examined the impact of tumor and sociodemographic factors on receiving preoperative RT. Methods and Materials: In total, 20,982 patients who underwent surgical resection for T3-T4 and/or node-positive rectal adenocarcinoma diagnosed from 2000 through 2006 were identified from the Surveillance, Epidemiology, and End Results tumor registries. We analyzed trends in preoperative RT use before and after publication of the findings from the German rectal study. We also performed multivariate logistic regression to identify factors associated with receiving preoperative RT. Results: Among those treated with RT, the proportion of patients treated with preoperative RT increased from 33.3% in 2000 to 63.8% in 2006. After adjustment for age; gender; race/ethnicity; marital status; Surveillance, Epidemiology, and End Results registry; county-level education; T stage; N stage; tumor size; and tumor grade, there was a significant association between later year of diagnosis and an increase in preoperative RT use (adjusted odds ratio, 1.26/y increase; 95% confidence interval, 1.23-1.29). When we compared the years before and after publication of the German rectal study (2000-2003 vs. 2004-2006), patients were more likely to receive preoperative RT than postoperative RT in 2004-2006 (adjusted odds ratio, 2.35; 95% confidence interval, 2.13-2.59). On multivariate analysis, patients who were older, who were female, and who resided in counties with lower educational levels had significantly decreased odds of receiving preoperative RT. Conclusions: After the publication of the landmark German rectal study, there was widespread, rapid adoption of preoperative RT for locally advanced rectal cancer. However, preoperative RT may be underused in certain sociodemographic groups.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Adjuvant Chemoradiation Therapy After Pancreaticoduodenectomy in Elderly Patients With Pancreatic Adenocarcinoma

Purpose: To evaluate the efficacy of adjuvant chemoradiation therapy (CRT) for pancreatic adenocarcinoma patients {>=}75 years of age. Methods: The study group of 655 patients underwent pancreaticoduodenectomy (PD) for pancreatic adenocarcinoma at the Johns Hopkins Hospital over a 12-year period (8/30/1993 to 2/28/2005). Demographic characteristics, comorbidities, intraoperative data, pathology data, and patient outcomes were collected and analyzed by adjuvant treatment status and age {>=}75 years. Cox proportional hazards analysis determined clinical predictors of mortality and morbidity. Results: We identified 166 of 655 (25.3%) patients were {>=}75 years of age and 489 of 655 patients (74.7%) were <75 years of age. Forty-nine patients in the elderly group (29.5%) received adjuvant CRT. For elderly patients, node-positive metastases (p = 0.008), poor/anaplastic differentiation (p = 0.012), and undergoing a total pancreatectomy (p = 0.010) predicted poor survival. The 2-year survival for elderly patients receiving adjuvant therapy was improved compared with surgery alone (49.0% vs. 31.6%, p = 0.013); however, 5-year survival was similar (11.7% vs. 19.8%, respectively, p = 0.310). After adjusting for major confounders, adjuvant therapy in elderly patients had a protective effect with respect to 2-year survival (relative risk [RR] 0.58, p = 0.044), but not 5-year survival (RR 0.80, p = 0.258). Among the nonelderly, CRT was significantly associated with 2-year survival (RR 0.60, p < 0.001) and 5-year survival (RR 0.69, p < 0.001), after adjusting for confounders. Conclusions: Adjuvant therapy after PD is significantly associated with increased 2-year but not 5-year survival in elderly patients. Additional studies are needed to select which elderly patients are likely to benefit from adjuvant CRT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Marginal Misses After Postoperative Intensity-Modulated Radiotherapy for Head and Neck Cancer

Purpose: To describe the spatial distribution of local-regional recurrence (LRR) among patients treated postoperatively with intensity-modulated radiotherapy (IMRT) for head and neck cancer. Methods and Materials: The medical records of 90 consecutive patients treated by gross total resection and postoperative IMRT for squamous cell carcinoma of the head and neck from January 2003 to July 2009 were reviewed. Sites of disease were the oral cavity (43 patients), oropharynx (20 patients), larynx (15 patients), and hypopharynx (12 patients). Fifty patients (56%) received concurrent chemotherapy. Results: Seventeen of 90 patients treated with postoperative IMRT experienced LRR, yielding a 2-year estimate of local regional control of 80%. Among the LRR patients, 11 patients were classified as in-field recurrences, occurring within the physician-designated clinical target volume, and 6 patients were categorized as marginal recurrences. There were no out-of-field geographical misses. Sites of marginal LRRs included the contralateral neck adjacent to the spared parotid gland (3 patients), the dermal/subcutaneous surface (2 patients), and the retropharyngeal/retrostyloid lymph node region (1 patient). Conclusions: Although the incidence of geographical misses was relatively low, the possibility of this phenomenon should be considered in the design of target volumes among patients treated by postoperative IMRT for head and neck cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Preoperative Chemoradiation for Rectal Cancer Using Capecitabine and Celecoxib Correlated With Posttreatment Assessment of Thymidylate Synthase and Thymidine Phosphorylase Expression

Purpose: Thymidylate synthase (TS) and thymidine phosphorylase (TP) expression have been shown to be predictors of response to therapy. The toxicity, efficacy, surgical morbidity, and immunohistochemical TS and TP expression were assessed in surgical resection specimens after preoperative chemoradiation. Methods and Materials: Twenty patients with clinical stage I to III rectal adenocarcinoma received preoperative chemoradiation and underwent surgical resection 6 weeks later. Results: Posttreatment tumor stages were T1 to T2 and N0 in 30% of patients; T3 to T4 and N0 in 30% of patients; and T1 to T3 and N1 to N2 in 15% of patients. Pathologic complete response (pCR) was evident in 25% and tumor regression occurred in a total of 80% of patients. Anal sphincter-sparing surgery was performed in 80% of cases. Acute and perioperative complications were minimal, with no grade 3/4 toxicity or treatment breaks. Pelvic control was obtained in 90% of patients. With a median follow-up of 65.5 months (range, 8-80 months), the 6-year actuarial survival rate was 75%. Local failure was significantly associated with nonresponse to therapy and with high TS and low TP expression (p = 0.008 and p = 0.04, respectively). Conclusions: The combination of capecitabine, celecoxib, and x-radiation therapy yields excellent response: a 25% pathologic pCR, no acute grade 3/4 toxicity, and minimal surgical morbidity. Nonresponders expressed significantly increased TS levels and decreased TP levels in posttreatment resection specimens compared to responders.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Impact of [{sup 18}F]Fluorodeoxyglucose PET-CT Staging on Treatment Planning in Radiotherapy Incorporating Elective Nodal Irradiation for Non-Small-Cell Lung Cancer: A Prospective Study;Non-small-cell lung cancer; PET; Radiotherapy; Elective nodal irradiation

Purpose: To evaluate prospectively how positron emission tomography (PET) information changes treatment plans for non-small-cell lung cancer (NSCLC) patients receiving or not receiving elective nodal irradiation (ENI). Methods and Materials: One hundred consecutive patients referred for curative radiotherapy were included in the study. Treatment plans were carried out with CT data sets only. For stage III patients, mediastinal ENI was planned. Then, patients underwent PET-CT for diagnostic/planning purposes. PET/CT was fused with the CT data for final planning. New targets were delineated. For stage III patients with minimal N disease (N0-N1, single N2), the ENI was omitted in the new plans. Patients were treated according to the PET-based volumes and plans. The gross tumor volume (GTV)/planning tumor volume (PTV) and doses for critical structures were compared for both data sets. The doses for areas of potential geographical misses derived with the CT data set alone were compared in patients with and without initially planned ENI. Results: In the 75 patients for whom the decision about curative radiotherapy was maintained after PET/CT, there would have been 20 cases (27%) with potential geographical misses by using the CT data set alone. Among them, 13 patients would receive ENI; of those patients, only 2 patients had the PET-based PTV covered by 90% isodose by using the plans based on CT alone, and the mean of the minimum dose within the missed GTV was 55% of the prescribed dose, while for 7 patients without ENI, it was 10% (p = 0.006). The lung, heart, and esophageal doses were significantly lower for plans with ENI omission than for plans with ENI use based on CT alone. Conclusions: PET/CT should be incorporated in the planning of radiotherapy for NSCLC, even in the setting of ENI. However, if PET/CT is unavailable, ENI may to some extent compensate for an inadequate dose coverage resulting from diagnostic uncertainties.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Salvage Reirradiaton With Stereotactic Body Radiotherapy for Locally Recurrent Head-and-Neck Tumors

Purpose: In this study, we present our results of reirradiation of locally recurrent head-and-neck cancer with image-guided, fractionated, frameless stereotactic body radiotherapy technique. Methods and Materials: From July 2007 to February 2009, 46 patients were treated using the CyberKnife (Accuray, Sunnyvale, CA) at the Department of Radiation Oncology, Hacettepe University, Ankara, Turkey. All patients had recurrent, unresectable, and previously irradiated head-and-neck cancer. The most prominent site was the nasopharynx (32.6%), and the most common histopathology was epidermoid carcinoma. The planning target volume was defined as the gross tumor volume identified on magnetic resonance imaging and computed tomography. There were 22 female and 24 male patients. Median age was 53 years (range, 19-87 years). The median tumor dose with stereotactic body radiotherapy was 30 Gy (range, 18-35 Gy) in a median of five (range, one to five) fractions. Results: Of 37 patients whose response to therapy was evaluated, 10 patients (27%) had complete tumor regression, 11 (29.8%) had partial response, and 10 (27%) had stable disease. Ultimate local disease control was achieved in 31 patients (83.8%). The overall survival was 11.93 months in median (ranged, 11.4 - 17.4 months), and the median progression free survival was 10.5 months. One-year progression-free survival and overall survival were 41% and 46%, respectively. Grade II or greater long-term complications were observed in 6 (13.3%) patients. On follow-up, 8 (17.3%) patients had carotid blow-out syndrome, and 7 (15.2%) patients died of bleeding from carotid arteries. We discovered that this fatal syndrome occurred only in patients with tumor surrounding carotid arteries and carotid arteries receiving all prescribed dose. Conclusions: Stereotactic body radiotherapy is an appealing treatment option for patients with recurrent head-and-neck cancer previously treated with radiation to high doses. Good local control with considerable 1-year survival is achieved with a relatively high rate of morbidity and related mortality.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Efficacy and Toxicity of Chemoradiotherapy Using Intensity-Modulated Radiotherapy for Unknown Primary of Head and Neck

Purpose: No single standard treatment paradigm is available for head-and-neck squamous cell carcinoma of an unknown primary (HNCUP). Bilateral neck radiotherapy with mucosal axis irradiation is widely used, with or without chemotherapy and/or surgical resection. Intensity-modulated radiotherapy (IMRT) is a highly conformal method for delivering radiation that is becoming the standard of care and might reduce the long-term treatment-related sequelae. We report the Dana-Farber Cancer Institute experience with IMRT-based treatment for HNCUP. Patients and Materials: A retrospective study of all patients treated at the Dana-Farber Cancer Institute for HNCUP with IMRT between August 2004 and January 2009. The primary endpoint was overall survival; the secondary endpoints were locoregional and distant control, and acute and chronic toxicity. Results: A total of 24 patients with HNCUP were included. Of these patients, 22 had Stage N2 disease or greater. All patients underwent neck computed tomography, positron emission tomography-computed tomography, and examination under anesthesia with directed biopsies. Of the 24 patients, 22 received concurrent chemotherapy, and 7 (29%) also underwent induction chemotherapy. The median involved nodal dose was 70 Gy, and the median mucosal dose was 60 Gy. With a median follow-up of 2.1 years, the 2-year actuarial overall survival and locoregional control rate was 92% and 100%, respectively. Only 25% of the patients had Grade 2 xerostomia, although 11 patients (46%) required esophageal dilation for stricture. Conclusion: In a single-institution series, IMRT-based chemoradiotherapy for HNCUP was associated with superb overall survival and locoregional control. The xerostomia rates were promising, but the aggressive therapy was associated with significant rates of esophageal stenosis.

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

Clinical Outcomes of Intensity-Modulated Pelvic Radiation Therapy for Carcinoma of the Cervix

Purpose: To evaluate disease outcomes and toxicity in cervical cancer patients treated with pelvic intensity-modulated radiation therapy (IMRT). Methods and Materials: We included all patients with Stage I-IVA cervical carcinoma treated with IMRT at three different institutions from 2000-2007. Patients treated with extended field or conventional techniques were excluded. Intensity-modulated radiation therapy plans were designed to deliver 45 Gy in 1.8-Gy daily fractions to the planning target volume while minimizing dose to the bowel, bladder, and rectum. Toxicity was graded according to the Radiation Therapy Oncology Group system. Overall survival and disease-free survival were estimated by use of the Kaplan-Meier method. Pelvic failure, distant failure, and late toxicity were estimated by use of cumulative incidence functions. Results: The study included 111 patients. Of these, 22 were treated with postoperative IMRT, 8 with IMRT followed by intracavitary brachytherapy and adjuvant hysterectomy, and 81 with IMRT followed by planned intracavitary brachytherapy. Of the patients, 63 had Stage I-IIA disease and 48 had Stage IIB-IVA disease. The median follow-up time was 27 months. The 3-year overall survival rate and the disease-free survival rate were 78% (95% confidence interval [CI], 68-88%) and 69% (95% CI, 59-81%), respectively. The 3-year pelvic failure rate and the distant failure rate were 14% (95% CI, 6-22%) and 17% (95% CI, 8-25%), respectively. Estimates of acute and late Grade 3 toxicity or higher were 2% (95% CI, 0-7%) and 7% (95% CI, 2-13%), respectively. Conclusions: Intensity-modulated radiation therapy is associated with low toxicity and favorable outcomes, supporting its safety and efficacy for cervical cancer. Prospective clinical trials are needed to evaluate the comparative efficacy of IMRT vs. conventional techniques.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Do Elderly Patients Experience Increased Perioperative or Postoperative Morbidity or Mortality When Given Neoadjuvant Chemoradiation Before Esophagectomy?

Background: The use of induction chemoradiotherapy followed by surgery has been widely used for the treatment of esophageal cancer. The presumed risk of increased postoperative morbidity and mortality with this regimen has led to reluctance to offer this therapy to elderly patients. We compared the perioperative morbidity and mortality of patients 70 years old and older with those of patients younger than 70 who received CRT followed by esophagectomy and sought to identify preoperative risk factors that may predict higher risk of postoperative death or complications. Methods and Materials: We identified 260 patients who underwent preoperative chemoradiotherapy followed by esophagectomy. The association of age with postoperative death and complications was evaluated. The Charlson index, prior cardiac history, and diabetes were identified as preoperative risk factors and were evaluated as potential confounders or effect modifiers. Results: Cardiac disease and the Charlson index were potential modifiers of the effect of age on length of hospital stay (p = 0.08 and p = 0.07, respectively) and postoperative complications (p = 0.1 and p = 0.2) but were not statistically significant. There was a slight nonsignificant decrease in the risk of death in elderly patients after adjustment for the Charlson index (p = 0.2). Conclusion: No significant differences were detected with respect to morbidity and mortality in elderly patients. The presence of cardiac disease, higher scores on the Charlson index, or diabetes did not significantly influence length of stay, postoperative complications, or postoperative death. Given the potential to improve outcomes, this regimen should not be discounted in elderly patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Pancreatic Cancer Tumor Size on CT Scan Versus Pathologic Specimen: Implications for Radiation Treatment Planning

Purpose: Pancreatic cancer primary tumor size measurements are often discordant between computed tomography (CT) and pathologic specimen after resection. Dimensions of the primary tumor are increasingly relevant in an era of highly conformal radiotherapy. Methods and Materials: We retrospectively evaluated 97 consecutive patients with resected pancreatic cancer at two Boston hospitals. All patients had CT scans before surgical resection. Primary endpoints were maximum dimension (in millimeters) of the primary tumor in any direction as reported by the radiologist on CT and by the pathologist for the resected gross fresh specimen. Endoscopic ultrasound (EUS) findings were analyzed if available. Results: Of the patients, 87 (90%) had preoperative CT scans available for review and 46 (47%) had EUS. Among proximal tumors (n = 69), 40 (58%) had pathologic duodenal invasion, which was seen on CT in only 3 cases. The pathologic tumor size was a median of 7 mm larger compared with CT size for the same patient (range, -15 to 43 mm; p < 0.0001), with 73 patients (84%) having a primary tumor larger on pathology than CT. Endoscopic ultrasound was somewhat more accurate, with pathologic tumor size being a median of only 5 mm larger compared with EUS size (range, -15 to 35 mm; p = 0.0003). Conclusions: Computed tomography scans significantly under-represent pancreatic cancer tumor size compared with pathologic specimens in resectable cases. We propose a clinical target volume expansion formula for the primary tumor based on our data. The high rate of pathologic duodenal invasion suggests a risk of duodenal undercoverage with highly conformal radiotherapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Outcomes of Postoperative Simultaneous Modulated Accelerated Radiotherapy for Head-and-Neck Squamous Cell Carcinoma

Purpose: To evaluate the treatment efficacy and toxicity of postoperative simultaneous modulated accelerated radiotherapy (SMART) for patients with head-and-neck squamous cell carcinoma (HNSCC). Methods and Materials: Between February 2003 and September 2008, 51 patients with histologically confirmed HNSCC received postoperative intensity-modulated radiotherapy (N = 33) or helical tomotherapy (N = 18) using SMART after curative surgical resection. The sites included were the oral cavity (OC), oropharynx (OP), larynx, and hypopharynx in 23, 20, 5, and 3 patients, respectively. Results: The median follow-up duration of all patients and surviving patients were 32 (range, 5-78 months) and 39 months (range, 9-77 months), respectively. The 3-year overall survival, cause-specific survival, disease-free survival, locoregional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS) in all patients were 71%, 77%, 75%, 85%, and 82%, respectively. Although no significant difference in 3-year LRRFS were found between OC (82%) and OP (82%) carcinomas, the 3-year DMFS was worse in cases of OC (66%) carcinoma compared with OP carcinoma (95%; p = 0.0414). Acute Grade 3 dermatitis, mucositis, and esophagitis occurred in 10%, 10%, and 2% of patients, respectively. At the last follow-up, Grade 3 xerostomia was documented in 10% of the patients. Young age ({<=}40 years) (p < 0.001) and OC carcinoma primary (p = 0.0142) were poor risk factors on univariate analysis for DMFS. Conclusion: Postoperative SMART was observed to be effective and safe in patients with HNSCC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Survival Outcomes in Resected Extrahepatic Cholangiocarcinoma: Effect of Adjuvant Radiotherapy in a Surveillance, Epidemiology, and End Results Analysis

Purpose: The benefit of adjuvant radiotherapy (RT) after surgical resection for extrahepatic cholangiocarcinoma has not been clearly established. We analyzed survival outcomes of patients with resected extrahepatic cholangiocarcinoma and examined the effect of adjuvant RT. Methods and Materials: Data were obtained from the Surveillance, Epidemiology, and End Results (SEER) program between 1973 and 2003. The primary endpoint was the overall survival time. Cox regression analysis was used to perform univariate and multivariate analyses of the following clinical variables: age, year of diagnosis, histologic grade, localized (Stage T1-T2) vs. regional (Stage T3 or greater and/or node positive) stage, gender, race, and the use of adjuvant RT after surgical resection. Results: The records for 2,332 patients were obtained. Patients with previous malignancy, distant disease, incomplete or conflicting records, atypical histologic features, and those treated with preoperative/intraoperative RT were excluded. Of the remaining 1,491 patients eligible for analysis, 473 (32%) had undergone adjuvant RT. After a median follow-up of 27 months (among surviving patients), the median overall survival time for the entire cohort was 20 months. Patients with localized and regional disease had a median survival time of 33 and 18 months, respectively (p < .001). The addition of adjuvant RT was not associated with an improvement in overall or cause-specific survival for patients with local or regional disease. Conclusion: Patients with localized disease had significantly better overall survival than those with regional disease. Adjuvant RT was not associated with an improvement in long-term overall survival in patients with resected extrahepatic bile duct cancer. Key data, including margin status and the use of combined chemotherapy, was not available through the SEER database.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Single-Fraction Stereotactic Body Radiation Therapy and Sequential Gemcitabine for the Treatment of Locally Advanced Pancreatic Cancer

Purpose: This Phase II trial evaluated the toxicity, local control, and overall survival in patients treated with sequential gemcitabine and linear accelerator-based single-fraction stereotactic body radiotherapy (SBRT). Methods and Materials: Twenty patients with locally advanced, nonmetastatic pancreatic adenocarcinoma were enrolled on this prospective single-institution, institutional review board-approved study. Gemcitabine was administered on Days 1, 8, and 15, and SBRT on Day 29. Gemcitabine was restarted on Day 43 and continued for 3-5 cycles. SBRT of 25 Gy in a single fraction was delivered to the internal target volume with a 2- 3-mm margin using a nine-field intensity-modulated radiotherapy technique. Respiratory gating was used to account for breathing motion. Follow-up evaluations occurred at 4-6 weeks, 10-12 weeks, and every 3 months after SBRT. Results: All patients completed SBRT and a median of five cycles of chemotherapy. Follow-up for the 2 remaining alive patients was 25.1 and 36.4 months. No acute Grade 3 or greater nonhematologic toxicity was observed. Late Grade 3 or greater toxicities occurred in 1 patient (5%) and consisted of a duodenal perforation (G4). Three patients (15%) developed ulcers (G2) that were medically managed. Overall, median survival was 11.8 months, with 1-year survival of 50% and 2-year survival of 20%. Using serial computed tomography, the freedom from local progression was 94% at 1 year. Conclusion: Linear accelerator-delivered SBRT with sequential gemcitabine resulted in excellent local control of locally advanced pancreatic cancer. Future studies will address strategies for reducing long-term duodenal toxicity associated with SBRT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Preoperative Chemoradiotherapy (CRT) Followed by Laparoscopic Surgery for Rectal Cancer: Predictors of the Tumor Response and the Long-Term Oncologic Outcomes

Purpose: We have evaluated the predictors of a tumor response to chemoradiotherapy (CRT) and the long-term oncologic outcomes of preoperative CRT and laparoscopic surgery for patients who suffer from rectal cancer. Methods and Materials: The study involved 274 patients with locally advanced rectal cancer and who had been treated with preoperative CRT and curative laparoscopic total mesorectal excision between January 2003 and January 2009. We assessed the long-term oncologic outcomes, in terms of recurrence and survival, of the treated patients. Results: Forty-two (15.3%) of the 274 patients had complete pathologic responses (pCR). The pre-CRT carcinoembryonic antigen level was the only significant predictor of a pCR on the multivariate analysis (p = 0.01). The overall survival at 5 years was 73.1%, with a mean survival period of 59.7 months (95% CI, 57.1-62.3). The disease-free survival at 5 years was 67.3% with a mean survival period of 54.7 months (95% CI, 51.7-57.8). The pCR group had a higher rate of overall survival at 5 years than did the non-pCR group, and the difference was significant (86.0% vs. 71.2%; hazard ratio = 0.87; 95% CI, 0.78-0.96; p = 0.03). The cumulative incidences of local and distant recurrences at 5 years were 5.8% and 28.3%, respectively. A total of 84.5% (234 of 274) of the patients had their anal sphincters preserved. Grade 3 or 4 acute and long-term toxic effects occurred in 22.2% and 8.4% of the patients, respectively. Conclusion: Preoperative CRT and laparoscopic surgery seems safe and feasible with favorable long-term outcomes and a high rate of sphincter preservation for the patients with low-lying tumors of the rectum.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Multi-Institutional Phase II Study of Proton Beam Therapy for Organ-Confined Prostate Cancer Focusing on the Incidence of Late Rectal Toxicities

Purpose: Proton beam therapy (PBT) is theoretically an excellent modality for external beam radiotherapy, providing an ideal dose distribution. However, it is not clear whether PBT for prostate cancer can clinically control toxicities. The purpose of the present study was to estimate prospectively the incidence of late rectal toxicities after PBT for organ-confined prostate cancer. Methods and Materials: The major eligibility criteria included clinical Stage T1-T2N0M0; initial prostate-specific antigen level of {<=}20 ng/mL and Gleason score {<=}7; no hormonal therapy or hormonal therapy within 12 months before registration; and written informed consent. The primary endpoint was the incidence of late Grade 2 or greater rectal toxicity at 2 years. Three institutions in Japan participated in the present study after institutional review board approval from each. PBT was delivered to a total dose of 74 GyE in 37 fractions. The patients were prospectively followed up to collect the data on toxicities using the National Cancer Institute-Common Toxicity Criteria, version 2.0. Results: Between 2004 and 2007, 151 patients were enrolled in the present study. Of the 151 patients, 75, 49, 9, 17, and 1 had Stage T1c, T2a, T2b, T2c, and T3a, respectively. The Gleason score was 4, 5, 6, and 7 in 5, 15, 80 and 51 patients, respectively. The initial prostate-specific antigen level was <10 or 10-20 ng/mL in 102 and 49 patients, respectively, and 42 patients had received hormonal therapy and 109 had not. The median follow-up period was 43.4 months. Acute Grade 2 rectal and bladder toxicity temporarily developed in 0.7% and 12%, respectively. Of the 147 patients who had been followed up for >2 years, the incidence of late Grade 2 or greater rectal and bladder toxicity was 2.0% (95% confidence interval, 0-4.3%) and 4.1% (95% confidence interval, 0.9-7.3%) at 2 years, respectively. Conclusion: The results of the present prospective study have revealed a valuable piece of evidence that PBT for localized prostate cancer can achieve a low incidence of late Grade 2 or greater rectal toxicities.

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