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DOE OSTI2012

Multimodality Local Therapy for Retroperitoneal Sarcoma

Purpose: Soft-tissue sarcomas of the retroperitoneum are rare tumors comprising less than 1% of all malignancies. Although surgery continues as the mainstay of treatment, the large size of these tumors coupled with their proximity to critical structures make resection with wide margins difficult to achieve. The role and timing of radiotherapy are controversial. This study updates our institutional experience using multimodality local therapy for resectable retroperitoneal sarcoma and identifies prognostic factors impacting disease control and survival. Methods and Materials: Between 1974 and 2007, 58 patients with nonmetastatic retroperitoneal sarcoma were treated with surgery and radiation at University of Florida. The median age at radiotherapy was 57 years old (range, 18-80 years). Forty-two patients received preoperative radiotherapy and 16 received postoperative radiotherapy. Nineteen patients received 1.8 Gy once daily and 39 patients received 1.2 Gy twice daily. Variables analyzed for prognostic value included age, grade, kidney involvement, histology, de novo versus recurrent presentation, tumor diameter, margin status, radiotherapy sequencing (preoperative vs. postoperative), total radiation dose, fractionation scheme, and treatment era. Results: The 5-year overall survival, cause-specific survival, and local control rates were 49%, 58%, and 62%, respectively. Nearly two-thirds of disease failures involved a component of local progression. On multivariate analysis, only margin status was significantly associated with improved 5-year local control (85%, negative margins; 63%, microscopic positive margins; 0%, gross positive margins; p < 0.0001) and 5-year overall survival (64%, negative margins; 56%, microscopic positive margins; 13%, gross positive margins; p = 0.0012). Thirty-one Grade 3 or greater toxicities were observed in 22 patients, including two treatment-related deaths (3%). Conclusion: For retroperitoneal sarcoma, local control remains a challenge and combined-modality therapy may be associated with significant acute and late morbidity. Our patterns of failure data suggest that improvements in local control may translate into a survival benefit.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Evaluation of nano/submicro pores in suspension plasma sprayed YSZ coatings

Nano-submicro pores could considerably influence the coating performances and thus should be carefully designed for the intended applications. However, it is challenging to characterize accurately such small pores in coatings. In this study, YSZ coatings were firstly manufactured by suspension plasma spray (SPS) and the nano-submicro pores in as-prepared coatings were investigated using Ultra-small-angle X-ray scattering (USAXS). Afterwards, a multivariate analysis on the effect of five different process parameters was carried out. The two main results showed that: 1) the nano-submicro pores content in coatings has a negative correlation with suspension mass load and powder size, and a positive correlation with spray distance, spray step, and substrate surface roughness; 2) suspension mass load is the main factor affecting the content of nano-submicro pores. Then, a mathematical model for the prediction of nanosubmicro pores was developed, and the control of nano-submicro pores content by using the predictive model was presented. Finally, the sintering effect on the evolution of nano-submicro pores was studied using USAXS as well.

36 MATERIALS SCIENCE↗

DOE OSTI2012

Frequency and Clinical Significance of Previously Undetected Incidental Findings Detected on Computed Tomography Simulation Scans for Breast Cancer Patients

Purpose: To determine the frequency and clinical significance of previously undetected incidental findings found on computed tomography (CT) simulation images for breast cancer patients. Methods and Materials: All CT simulation images were first interpreted prospectively by radiation oncologists and then double-checked by diagnostic radiologists. The official reports of CT simulation images for 881 consecutive postoperative breast cancer patients from 2009 to 2010 were retrospectively reviewed. Potentially important incidental findings (PIIFs) were defined as any previously undetected benign or malignancy-related findings requiring further medical follow-up or investigation. For all patients in whom a PIIF was detected, we reviewed the clinical records to determine the clinical significance of the PIIF. If the findings from the additional studies prompted by a PIIF required a change in management, the PIIF was also recorded as a clinically important incidental finding (CIIF). Results: There were a total of 57 (6%) PIIFs. The 57 patients in whom a PIIF was detected were followed for a median of 17 months (range, 3-26). Six cases of CIIFs (0.7% of total) were detected. Of the six CIIFs, three (50%) cases had not been noted by the radiation oncologist until the diagnostic radiologist detected the finding. On multivariate analysis, previous CT examination was an independent predictor for PIIF (p = 0.04). Patients who had not previously received chest CT examinations within 1 year had a statistically significantly higher risk of PIIF than those who had received CT examinations within 6 months (odds ratio, 3.54; 95% confidence interval, 1.32-9.50; p = 0.01). Conclusions: The rate of incidental findings prompting a change in management was low. However, radiation oncologists appear to have some difficulty in detecting incidental findings that require a change in management. Considering cost, it may be reasonable that routine interpretations are given to those who have not received previous chest CT examinations within 1 year.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2012

Multi-Institutional Experience of Ductal Carcinoma In Situ in Black vs White Patients Treated With Breast-Conserving Surgery and Whole Breast Radiation Therapy

Purpose: Given the paucity of data on racial disparities in ductal carcinoma in situ (DCIS), the data from a multi-institutional cohort of DCIS patients treated with breast-conserving surgery and whole breast radiation therapy (RT) were analyzed to determine whether racial disparities or differences exist. Methods and Materials: A total of 533 white and 76 black DCIS patients from 3 university-based cancer centers were uniformly treated with breast-conserving surgery and RT. All patient data were collected and analyzed as a function of race. Results: The median follow-up was 5.2 years. No significant racial differences were seen in tumor size, age at diagnosis, estrogen receptor status, necrosis, or grade (all P>.05). Of the treatment parameters, the RT dose delivered, boost, positive margin rates, frequency of hormone receptor status assessment, and receipt of hormonal therapy for the 2 cohorts did not significantly differ (all P>.05). The local relapse-free survival was similar at 5 years (96.1% and 98.1%, P=.399) and 10 years (92.8% vs 95.8%, P=.360), with no significant overall survival difference at 10 years (94.0% vs 88.9%, P=.290) between the white and black patients, respectively. On multivariate analysis, race was not an independent predictor of local relapse-free survival or overall survival when accounting for age, grade, and margin status. Conclusion: In our large cohort of DCIS patients uniformly treated at 3 institutions with breast conservation without any apparent differences in treatment delivery parameters, we demonstrated that the clinical and pathologic features and local survival outcomes did not differ as a function of race. Our results suggest that when black patients with DCIS are appropriately selected for breast conservation and receive adjuvant RT without racial disparities in the treatment parameters, differences in the outcomes as a function of race do not exist.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2013

High-Dose Hypofractionated Proton Beam Radiation Therapy Is Safe and Effective for Central and Peripheral Early-Stage Non-Small Cell Lung Cancer: Results of a 12-Year Experience at Loma Linda University Medical Center

Purpose: We update our previous reports on the use of hypofractionated proton beam radiation therapy for early-stage lung cancer patients. Methods and Materials: Eligible subjects had biopsy-proven non-small cell carcinoma of the lung and were medically inoperable or refused surgery. Clinical workup required staging of T1 or T2, N0, M0. Subjects received hypofractionated proton beam therapy to the primary tumor only. The dose delivered was sequentially escalated from 51 to 60 Gy, then to 70 Gy in 10 fractions over 2 weeks. Endpoints included toxicity, pulmonary function, overall survival (OS), disease-specific survival (DSS), and local control (LC). Results: One hundred eleven subjects were analyzed for treatment outcomes. The patient population had the following average characteristics; age 73.2 years, tumor size 3.6 cm, and 1.33 L forced expiratory volume in 1 second. The entire group showed improved OS with increasing dose level (51, 60, and 70 Gy) with a 4-year OS of 18%, 32%, and 51%, respectively (P=.006). Peripheral T1 tumors exhibited LC of 96%, DSS of 88%, and OS of 60% at 4 years. Patients with T2 tumors showed a trend toward improved LC and survival with the 70-Gy dose level. On multivariate analysis, larger tumor size was strongly associated with increased local recurrence and decreased survival. Central versus peripheral location did not correlate with any outcome measures. Clinical radiation pneumonitis was not found to be a significant complication, and no patient required steroid therapy after treatment for radiation pneumonitis. Pulmonary function was well maintained 1 year after treatment. Conclusions: High-dose hypofractionated proton therapy achieves excellent outcomes for lung carcinomas that are peripherally or centrally located. The 70-Gy regimen has been adopted as standard therapy for T1 tumors at our institution. Larger T2 tumors show a trend toward improved outcomes with higher doses, suggesting that better results could be seen with intensified treatment.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2013

Vibrational spectroscopy for online monitoring of extraction solvent degradation products

In our research, we are exploring the potential of online monitoring of the organic solvents for the flowsheets relevant to the used nuclear fuel reprocessing and tributyl phosphate (TBP)- based extraction processes in particular. Utilization of vibrational spectroscopic techniques permits the discrimination of the degradation products from the primary constituents of the loaded extraction solvent. Multivariate analysis of the spectral data facilitates development of the regression models for their quantification in real time and potentially enables online implementation of a monitoring system. Raman and FTIR spectral databases were created and used to develop the regression partial least squares (PLS) chemometric models for the quantitative prediction of HDBP (dibutyl phosphoric acid) degradation product, TBP, and UO{sub 2}{sup 2+} extraction organic product phase. It was demonstrated that both these spectroscopic techniques are suitable for the quantification of the Purex solvent components in the presence of UO{sub 2}(NO{sub 3}){sub 2}. Developed PLS models successfully predicted HDBP and TBP organic concentrations in simulated Purex solutions.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2012

Intensity-Modulated Radiotherapy for Tumors of the Nasal Cavity and Paranasal Sinuses: Clinical Outcomes and Patterns of Failure

Purpose: To report outcomes in patients treated with intensity-modulated radiotherapy (IMRT) for tumors of the paranasal sinuses and nasal cavity (PNS/NC). Methods/Materials: Between June 2000 and December 2009, 52 patients with tumors of the PNS/NC underwent postoperative or definitive radiation with IMRT. Twenty-eight (54%) patients had squamous cell carcinoma (SCC). Twenty-nine patients (56%) received chemotherapy. The median follow-up was 26.6 months (range, 2.9-118.4) for all patients and 30.9 months for living patients. Results: Eighteen patients (35%) developed local-regional failure (LRF) at median time of 7.2 months. Thirteen local failures (25%) were observed, 12 in-field and 1 marginal. Six regional failures were observed, two in-field and four out-of-field. No patients treated with elective nodal radiation had nodal regional failure. Two-year local-regional control (LRC), in-field LRC, freedom from distant metastasis (FFDM), and overall survival (OS) were 64%, 74%, 71%, and 66% among all patients, respectively, and 43%, 61%, 61%, and 53% among patients with SCC, respectively. On multivariate analysis, SCC and >1 subsite involved had worse LRC (p = 0.0004 and p = 0.046, respectively) and OS (p = 0.003 and p = 0.046, respectively). Cribriform plate invasion (p = 0.005) and residual disease (p = 0.047) also had worse LRC. Acute toxicities included Grade {>=}3 mucositis in 19 patients (37%), and Grade 3 dermatitis in 8 patients (15%). Six patients had Grade {>=}3 late toxicity including one optic toxicity. Conclusions: IMRT for patients with PNS/NC tumors has good outcomes compared with historical series and is well tolerated. Patients with SCC have worse LRC and OS. LRF is the predominant pattern of failure.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2012

Gamma Knife Stereotactic Radiosurgery as Salvage Therapy After Failure of Whole-Brain Radiotherapy in Patients With Small-Cell Lung Cancer

Purpose: Radiosurgery has been successfully used in selected cases to avoid repeat whole-brain irradiation (WBI) in patients with multiple brain metastases of most solid tumor histological findings. Few data are available for the use of radiosurgery for small-cell lung cancer (SCLC). Methods and Materials: Between November 1999 and June 2009, 51 patients with SCLC and previous WBI and new brain metastases were treated with GammaKnife stereotactic radiosurgery (GKSRS). A median dose of 18 Gy (range, 10-24 Gy) was prescribed to the margin of each metastasis. Patients were followed with serial imaging. Patient electronic records were reviewed to determine disease-related factors and clinical outcomes after GKSRS. Local and distant brain failure rates, overall survival, and likelihood of neurologic death were determined based on imaging results. The Kaplan-Meier method was used to determine survival and local and distant brain control. Cox proportional hazard regression was performed to determine strength of association between disease-related factors and survival. Results: Median survival time for the entire cohort was 5.9 months. Local control rates at 1 and 2 years were 57% and 34%, respectively. Distant brain failure rates at 1 and 2 years were 58% and 75%, respectively. Fifty-three percent of patients ultimately died of neurologic death. On multivariate analysis, patients with stable (hazard ratio [HR] = 2.89) or progressive (HR = 6.98) extracranial disease (ECD) had worse overall survival than patients without evidence of ECD (p = 0.00002). Concurrent chemotherapy improved local control (HR = 89; p = 0.006). Conclusions: GKSRS represents a feasible salvage option in patients with SCLC and brain metastases for whom previous WBI has failed. The status of patients' ECD is a dominant factor predictive of overall survival. Local control may be inferior to that seen with other cancer histological results, although the use of concurrent chemotherapy may help to improve this.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2013

A Model to Estimate the Risk of Breast Cancer-Related Lymphedema: Combinations of Treatment-Related Factors of the Number of Dissected Axillary Nodes, Adjuvant Chemotherapy, and Radiation Therapy

Purpose: The development of breast cancer-related lymphedema (LE) is closely related to the number of dissected axillary lymph nodes (N-ALNs), chemotherapy, and radiation therapy. In this study, we attempted to estimate the risk of LE based on combinations of these treatment-related factors. Methods and Materials: A total of 772 patients with breast cancer, who underwent primary surgery with axillary lymph node dissection from 2004 to 2009, were retrospectively analyzed. Adjuvant chemotherapy (ACT) was performed in 677 patients (88%). Among patients who received radiation therapy (n=675), 274 (35%) received supraclavicular radiation therapy (SCRT). Results: At a median follow-up of 5.1 years (range, 3.0-8.3 years), 127 patients had developed LE. The overall 5-year cumulative incidence of LE was 17%. Among the 127 affected patients, LE occurred within 2 years after surgery in 97 (76%) and within 3 years in 115 (91%) patients. Multivariate analysis showed that N-ALN (hazard ratio [HR], 2.81; P<.001), ACT (HR, 4.14; P=.048), and SCRT (HR, 3.24; P<.001) were independent risk factors for LE. The total number of risk factors correlated well with the incidence of LE. Patients with no risk or 1 risk factor showed a significantly lower 5-year probability of LE (3%) than patients with 2 (19%) or 3 risk factors (38%) (P<.001). Conclusions: The risk factors associated with LE were N-ALN, ACT, and SCRT. A simple model using combinations of these factors may help clinicians predict the risk of LE.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2016

The Influence of Diabetes Mellitus and Metformin on Distant Metastases in Oropharyngeal Cancer: A Multicenter Study

Purpose: Local control in oropharyngeal cancer has improved to unprecedented rates with combined modality therapy; as a result, distant metastases are becoming a principal challenge. We aimed to determine the impact of diabetes mellitus and metformin use on clinical outcomes in a large population of oropharyngeal cancer patients treated in the modern era. Methods and Materials: We identified 1745 consecutive patients with oropharyngeal cancer treated at 2 large cancer centers with external beam radiation therapy from 1998 to 2011. A total of 184 patients had diabetes mellitus at the time of diagnosis, of whom 102 were taking metformin. The outcomes assessed included local failure-free survival (LFFS), regional failure-free survival (RFFS), distant metastasis-free survival (DMFS), and overall survival (OS). Results: The median follow-up time was 4.3 years. The 5-year actuarial rates of DMFS were 89.6% for nondiabetic patients and 78.7% for diabetic nonmetformin users (P=.011) and of OS were 83.0% for nondiabetic patients and 70.7% for diabetic nonmetformin users (P=.048). Diabetic metformin users had 5-year DMFS (90.1%) and OS (89.6%) similar to those of nondiabetic patients. Multivariate analysis (diabetic nonmetformin users as reference) demonstrated improved DMFS for nondiabetic patients (adjusted hazard ratio 0.54; 95% confidence interval 0.32-0.93; P=.03) and a trend toward improved DMFS with metformin use (adjusted hazard ratio 0.46; 95% confidence interval 0.20-1.04; P=.06). LFFS and RFFS were high in all groups and were not significantly different by diabetic status or metformin use. Conclusions: Diabetic patients not using metformin independently have significantly higher rates of distant metastases than do nondiabetic patients, whereas metformin users have rates of distant metastases similar to those of nondiabetic patients. Further prospective investigation is warranted to validate the benefit of metformin in oropharyngeal cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2016

Distance to Radiation Facility and Treatment Choice in Early-Stage Breast Cancer

Purpose: Breast-conserving therapy (BCT) is a recommended alternative to mastectomy (MT) for early-stage breast cancer. Limited access to radiation therapy (RT) may result in higher rates of MT. We assessed the association between distance to the nearest RT facility and the use of MT, in a modern cohort of women. Methods and Materials: Women with stage 0-II breast cancer eligible for BCT diagnosed from 2004 to 2010 were identified from the Florida Cancer Data System (FCDS). Distances from patient census tracts to the nearest RT facility census tract were calculated. Multivariate logistic regression was used to identify explanatory variables that influenced MT use. Results: Of the 27,489 eligible women, 32.1% (n=8841) underwent MT, and 67.8% (n=18,648) underwent BCS. Thirty-two percent of patients lived in a census tract that was >5 miles from an RT facility. MT use increased with increasing distance to RT facility (31.1% at ≤5 miles, 33.8% at >5 to <15 miles, 34.9% at 15 to <40 miles, and 51% at ≥40 miles, P<.001). The likelihood was that MT was independently associated with increasing distance to RT facility on multivariate analysis (P<.001). Compared to patients living <5 miles away from an RT facility, patients living 15 to <40 miles away were 1.2 times more likely to be treated with MT (odds ratio [OR]: 1.19, 95% confidence interval [CI]: 1.05-1.35, P<.01), and those living ≥40 miles away were more than twice as likely to be treated with MT (OR: 2.17, 95% CI: 1.48-3.17, P<.001). However, in patients younger than 50 years (n=5179), MT use was not associated with distance to RT facility (P=.235). Conclusions: MT use in a modern cohort of women is independently associated with distance to RT facility. However, for young patients, distance to RT is not a significant explanatory variable for MT use.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2013

Long-term Survival Outcomes Following Internal Mammary Node Irradiation in Stage II-III Breast Cancer: Results of a Large Retrospective Study With 12-Year Follow-up

Purpose: To examine the effect of internal mammary node irradiation (IMNI) on disease-free survival (DFS) and overall survival (OS) in breast cancer patients treated with modified radical mastectomy and postoperative radiation therapy. Methods and Materials: Between 1994 and 2002, 396 patients with stage II-III breast cancer were treated with postmastectomy radiation therapy with (n=197) or without (n=199) IMNI. Patients who received neoadjuvant chemotherapy were excluded. IMNI was administered at the clinical discretion of the treating physician. Median RT dose was 50.4 Gy (range, 45.0-59.4 Gy) in 28 fractions, with inclusion of the supraclavicular fossa in 96% of patients. Adjuvant chemotherapy was administered to 99.7% of the patients and endocrine therapy to 53%. Results: The median follow-up was 149 months (range, 124-202). IMNI patients had more advanced nodal stage and non-high grade tumors than those without IMNI (P<.001). Otherwise, disease and treatment characteristics were well balanced. The 10-year DFS with and without IMNI was 65% and 57%, respectively (P=.05). Multivariate analysis demonstrated that IMNI was an independent, positive predictor of DFS (hazard ratio [HR], 0.70; P=.02). Benefits of IMNI in DFS were seen most apparently in N2 patients (HR, 0.44; 95% confidence interval [CI], 0.26-0.74) and inner/central tumors (HR, 0.55; 95% CI, 0.34-0.90). The 10-year OS with and without IMNI was 72% and 66%, respectively (P=.62). The 10-year DFS and OS were 61%, and 69%, respectively. Conclusions: Internal mammary node irradiation significantly improved DFS in postmastectomy breast cancer patients. Pending long-term results from randomized trials, treatment of internal mammary nodes should be considered in postmastectomy radiation therapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2015

The Feasibility of Percutaneous Renal Cryoablation Under Local Anaesthesia

ObjectivesThe aim of this study was to evaluate the feasibility of cryoablation of renal tumours without sedation.Materials and methodsWe prospectively evaluated 149 computed tomography-guided renal cryoablation procedures that were performed at our institution between 2009 and 2013. The patients received only 1 g of IV paracetamol prior to the procedure; intraprocedural, local anaesthesia was administered. We recorded the date and duration of the procedure, size and location of the tumour, number of cryoneedles used, need for dissection with saline or carbon dioxide and intraprocedural degree of pain, which was scored using an established visual analogue pain score (VAS) (0–10). Multivariate analysis was used to identify the associations between the recorded parameters and VAS.ResultsAn interventional radiologist and a technician could perform all procedures without the help of anaesthesiologists and with adequate analgesia. The pain level ranged from 0 to 8 (mean, 2.0). It did not correlate with the tumour size or with the number of cryoneedles. It was significantly greater when the ice ball involved renal cavities (p = .0033) and when carbon dioxide was used for dissection (p < .0001). Conversely, the team experience was positively correlated with lower pain levels (p = .0381).ConclusionThis study demonstrates that the cryoablation of renal tumours is feasible by interventional radiologists alone using a combination of IV paracetamol and local anaesthesia.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2013

Hearing Outcomes After Stereotactic Radiosurgery for Unilateral Intracanalicular Vestibular Schwannomas: Implication of Transient Volume Expansion

Purpose: We evaluated the prognostic factors for hearing outcomes after stereotactic radiosurgery (SRS) for unilateral sporadic intracanalicular vestibular schwannomas (IC-VSs) as a clinical homogeneous group of VSs. Methods and Materials: Sixty consecutive patients with unilateral sporadic IC-VSs, defined as tumors in the internal acoustic canal, and serviceable hearing (Gardner-Roberson grade 1 or 2) were treated with SRS as an initial treatment. The mean tumor volume was 0.34 {+-} 0.03 cm{sup 3} (range, 0.03-1.00 cm{sup 3}), and the mean marginal dose was 12.2 {+-} 0.1 Gy (range, 11.5-13.0 Gy). The median follow-up duration was 62 months (range, 36-141 months). Results: The actuarial rates of serviceable hearing preservation were 70%, 63%, and 55% at 1, 2, and 5 years after SRS, respectively. In multivariate analysis, transient volume expansion of {>=}20% from initial tumor size was a statistically significant risk factor for loss of serviceable hearing and hearing deterioration (increase of pure tone average {>=}20 dB) (odds ratio = 7.638; 95% confidence interval, 2.317-25.181; P=.001 and odds ratio = 3.507; 95% confidence interval, 1.228-10.018; P=.019, respectively). The cochlear radiation dose did not reach statistical significance. Conclusions: Transient volume expansion after SRS for VSs seems to be correlated with hearing deterioration when defined properly in a clinically homogeneous group of patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2012

Changes in Pulmonary Function Up to 10 Years After Locoregional Breast Irradiation

Purpose: To evaluate the long-term impact of locoregional breast radiotherapy (RT) on pulmonary function tests (PFTs). Methods and Materials: This study included 75 women who underwent postoperative locoregional breast RT. PFTs were performed before RT and 3, 6, and 12 months and 8 to 10 years after RT. By use of univariate and multivariate analyses, the impact of treatment- and patient-related factors on late changes in PFTs was evaluated. Results: During the first year after RT, all PFTs significantly worsened at 3 to 6 months after RT (p < 0.05). At 12 months, forced vital capacity (FVC), vital capacity (VC), and forced expiratory volume in 1 second (FEV{sub 1}) recovered almost to baseline values, whereas total lung capacity (TLC) and diffusion capacity of carbon monoxide (DL{sub CO}) recovered only slightly and were still found to be decreased compared with baseline (p < 0.05). At 8 to 10 years after RT, mean reductions in FEV{sub 1} of 4% (p = 0.03) and in VC, DL{sub CO}, and TLC of 5%, 9%, and 11% (all p < 0.0001), respectively, were observed compared with pre-RT values. On multivariate analysis, tamoxifen use negatively affected TLC at 8 to 10 years after RT (p = 0.033), whereas right-sided irradiation was associated with a late reduction in FEV{sub 1} (p = 0.027). For FEV{sub 1} and DL{sub CO}, an early decrease was predictive for a late decrease (p = 0.003 and p = 0.0009, respectively). Conclusions: The time course of PFT changes after locoregional RT for breast cancer follows a biphasic pattern. An early reduction in PFTs at 3 to 6 months with a partial recovery at 12 months after RT is followed by a late, more important PFT reduction up to 8 to 10 years after RT. Tamoxifen use may have an impact on this late decline in PFTs.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2012

Effect of Radiotherapy and Chemotherapy on the Risk of Mucositis During Intensity-Modulated Radiation Therapy for Oropharyngeal Cancer

Purpose: To define the roles of radiotherapy and chemotherapy on the risk of Grade 3+ mucositis during intensity-modulated radiation therapy (IMRT) for oropharyngeal cancer. Methods and Materials: 164 consecutive patients treated with IMRT at two institutions in nonoverlapping treatment eras were selected. All patients were treated with a dose painting approach, three dose levels, and comprehensive bilateral neck treatment under the supervision of the same radiation oncologist. Ninety-three patients received concomitant chemotherapy (cCHT) and 14 received induction chemotherapy (iCHT). Individual information of the dose received by the oral mucosa (OM) was extracted as absolute cumulative dose-volume histogram (DVH), corrected for the elapsed treatment days and reported as weekly (w) DVH. Patients were seen weekly during treatment, and peak acute toxicity equal to or greater than confluent mucositis at any point during the course of IMRT was considered the endpoint. Results: Overall, 129 patients (78.7%) reached the endpoint. The regions that best discriminated between patients with/without Grade 3+ mucositis were found at 10.1 Gy/w (V10.1) and 21 cc (D21), along the x-axis and y-axis of the OM-wDVH, respectively. On multivariate analysis, D21 (odds ratio [OR] = 1.016, 95% confidence interval [CI], 1.009-1.023, p < 0.001) and cCHT (OR = 4.118, 95% CI, 1.659-10.217, p = 0.002) were the only independent predictors. However, V10.1 and D21 were highly correlated (rho = 0.954, p < 0.001) and mutually interchangeable. cCHT would correspond to 88.4 cGy/w to at least 21 cc of OM. Conclusions: Radiotherapy and chemotherapy act independently in determining acute mucosal toxicity; cCHT increases the risk of mucosal Grade 3 toxicity Almost-Equal-To 4 times over radiation therapy alone, and it is equivalent to an extra Almost-Equal-To 6.2 Gy to 21 cc of OM over a 7-week course.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2012

Influence of Tumor Thrombus Location on the Outcome of External-beam Radiation Therapy in Advanced Hepatocellular Carcinoma With Macrovascular Invasion

Purpose: The present study evaluates the influence of portal vein (PV) vs. inferior vena cava (IVC) tumor thrombosis sites on the effectiveness of external-beam radiation therapy (EBRT) in advanced hepatocellular carcinoma (HCC) with macrovascular invasion. Methods and Materials: We retrospectively reviewed 181 HCC patients with PV and/or IVC tumor thrombi who were referred for EBRT at our institution between 2000 and 2009. EBRT was designed to focus on the tumor thrombi with or without primary intrahepatic tumors to deliver a median total conventional dose of 50 Gy (range, 30-60 Gy). Predictors of survival were identified using univariate and multivariate analyses. Results: The median survival was 10.2, 7.4, 17.4, and 8.5 months for patients with PV branch, PV trunk, IVC, and PV plus IVC tumor thrombosis, respectively. Unfavorable pretreatment predictors were associated by multivariate analysis with lower albumin and higher {alpha}-fetoprotein levels, poorer Child-Pugh liver function classification, multiple intrahepatic foci, lymph node metastases, thrombus location, less chance to receive post-EBRT transarterial chemoembolization (TACE) and the two-dimensional EBRT technique. In comparison to patients with PV tumor thrombosis, patients with IVC thrombi had a higher occurrence of solitary intrahepatic lesions (p = 0.027), well-controlled intrahepatic tumors (p < 0.001), and a better response to EBRT (p < 0.001), and they were more likely to receive post-EBRT TACE (p = 0.033). Conclusions: In HCC, patients with IVC thrombus treated with EBRT had a better response rate and longer survival than those with PV thrombus.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

Role of Genetic Polymorphisms in NFKB-Mediated Inflammatory Pathways in Response to Primary Chemoradiation Therapy for Rectal Cancer

Purpose: To investigate whether polymorphisms of genes related to inflammation are associated with pathologic response (primary endpoint) in patients with rectal cancer treated with primary chemoradiation therapy (PCRT). Methods and Materials: Genomic DNA of 159 patients with locally advanced rectal cancer treated with PCRT was genotyped for polymorphisms rs28362491 (NFKB1), rs1213266/rs5789 (PTGS1), rs5275 (PTGS2), and rs16944/rs1143627 (IL1B) using TaqMan single nucleotide polymorphism genotyping assays. The association between each genotype and pathologic response (poor response vs complete or partial response) was analyzed using logistic regression models. Results: The NFKB1 DEL/DEL genotype was associated with pathologic response (odds ratio [OR], 6.39; 95% confidence interval [CI], 0.78-52.65; P=.03) after PCRT. No statistically significant associations between other polymorphisms and response to PCRT were observed. Patients with the NFKB1 DEL/DEL genotype showed a trend for longer disease-free survival (log-rank test, P=.096) and overall survival (P=.049), which was not significant in a multivariate analysis that included pathologic response. Analysis for 6 polymorphisms showed that patients carrying the haplotype rs28362491-DEL/rs1143627-A/rs1213266-G/rs5789-C/rs5275-A/rs16944-G (13.7% of cases) had a higher response rate to PCRT (OR, 8.86; 95% CI, 1.21-64.98; P=.034) than the reference group (rs28362491-INS/rs1143627-A/rs1213266-G/rs5789-C/rs5275-A/rs16944-G). Clinically significant (grade ≥2) acute organ toxicity was also more frequent in patients with that same haplotype (OR, 4.12; 95% CI, 1.11-15.36; P=.037). Conclusions: Our results suggest that genetic variation in NFKB-related inflammatory pathways might influence sensitivity to primary chemoradiation for rectal cancer. If confirmed, an inflammation-related radiogenetic profile might be used to select patients with rectal cancer for preoperative combined-modality treatment.

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