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At least 1,585 records · Page 88

Bile Acid Malabsorption After Pelvic and Prostate Intensity Modulated Radiation Therapy: An Uncommon but Treatable Condition

Purpose: Intensity modulated radiation therapy (IMRT) is a significant therapeutic advance in prostate cancer, allowing increased tumor dose delivery and increased sparing of normal tissues. IMRT planning uses strict dose constraints to nearby organs to limit toxicity. Bile acid malabsorption (BAM) is a treatable disorder of the terminal ileum (TI) that presents with symptoms similar to radiation therapy toxicity. It has not been described in patients receiving RT for prostate cancer in the contemporary era. We describe new-onset BAM in men after IMRT for prostate cancer. Methods and Materials: Diagnosis of new-onset BAM was established after typical symptoms developed, selenium-75 homocholic acid taurine (SeHCAT) scanning showed 7-day retention of <15%, and patients' symptoms unequivocally responded to a bile acid sequestrant. The TI was identified on the original radiation therapy plan, and the radiation dose delivered was calculated and compared with accepted dose-volume constraints. Results: Five of 423 men treated in a prospective series of high-dose prostate and pelvic IMRT were identified with new onset BAM (median age, 65 years old). All reported having normal bowel habits before RT. The volume of TI ranged from 26-141 cc. The radiation dose received by the TI varied between 11.4 Gy and 62.1 Gy (uncorrected). Three of 5 patients had TI treated in excess of 45 Gy (equivalent dose calculated in 2-Gy fractions, using an {alpha}/{beta} ratio of 3) with volumes ranging from 1.6 cc-49.0 cc. One patient had mild BAM (SeHCAT retention, 10%-15%), 2 had moderate BAM (SeHCAT retention, 5%-10%), and 2 had severe BAM (SeHCAT retention, <5%). The 3 patients whose TI received {>=}45 Gy developed moderate to severe BAM, whereas those whose TI received <45 Gy had only mild to moderate BAM. Conclusions: Radiation delivered to the TI during IMRT may cause BAM. Identification of the TI from unenhanced RT planning computed tomography scans is difficult and may impede accurate dosimetric evaluation. Thorough toxicity assessment and close liaison between oncologist and gastroenterologist allow timely diagnosis and treatment.

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Electrophysiological Monitoring in Patients With Tumors of the Skull Base Treated by Carbon-12 Radiation Therapy

Purpose: To report the results of short-term electrophysiologic monitoring of patients undergoing {sup 12}C therapy for the treatment of skull chordomas and chondrosarcomas unsuitable for radical surgery. Methods and Materials: Conventional electroencephalogram (EEG) and retinal and cortical electrophysiologic responses to contrast stimuli were recorded from 30 patients undergoing carbon ion radiation therapy, within a few hours before the first treatment and after completion of therapy. Methodologies and procedures were compliant with the guidelines of the International Federation for Clinical Neurophysiology and International Society for Clinical Electrophysiology of Vision. Results: At baseline, clinical signs were reported in 56.6% of subjects. Electrophysiologic test results were abnormal in 76.7% (EEG), 78.6% (cortical evoked potentials), and 92.8% (electroretinogram) of cases, without correlation with neurologic signs, tumor location, or therapy plan. Results on EEG, but not electroretinograms and cortical responses, were more often abnormal in patients with reported clinical signs. Abnormal EEG results and retinal/cortical responses improved after therapy in 40% (EEG), 62.5% (cortical potentials), and 70% (electroretinogram) of cases. Results on EEG worsened after therapy in one-third of patients whose recordings were normal at baseline. Conclusions: The percentages of subjects whose EEG results improved or worsened after therapy and the improvement of retinal/cortical responses in the majority of patients are indicative of a limited or negligible (and possibly transient) acute central nervous system toxicity of carbon ion therapy, with a significant beneficial effect on the visual pathways. Research on large samples would validate electrophysiologic procedures as a possible independent test for central nervous system toxicity and allow investigation of the correlation with clinical signs; repeated testing over time after therapy would demonstrate, and may help predict, possible late toxicity.

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Phase 1 Clinical Trial of Stereotactic Body Radiation Therapy Concomitant With Neoadjuvant Chemotherapy for Breast Cancer

Purpose: Stereotactic body radiation therapy (SBRT) allows stereotactic irradiation of thoracic tumors. It may have a real impact on patients who may not otherwise qualify for breast-conserving surgery. We conducted a phase 1 trial that tested 5 dose levels of SBRT concomitant with neoadjuvant chemotherapy (NACT) before to surgery. The purpose of the current dose escalation study was to determine the maximum tolerable dose of SBRT in the treatment of breast cancer. Methods and Materials: To define toxicity, we performed dermatologic examinations that included clinical examinations by 2 separate physicians and technical evaluations using colorimetry, dermoscopy, and skin ultrasonography. Dermatologic examinations were performed before NACT, 36 and 56 days after the beginning of NACT, and before surgery. Surgery was performed 4 to 8 weeks after the last chemotherapy session. Efficacy, the primary endpoint, was determined by the pathologic complete response (pCR) rate. Results: Maximum tolerable dose was not reached. Only 1 case of dose-limiting toxicity was reported (grade 3 dermatologic toxicity), and SBRT was overall well tolerated. The pCR rate was 36%, with none being observed at the first 2 dose levels, and the highest rate being obtained at dose level 3 (25.5 Gy delivered in 3 fractions). Furthermore, the breast-conserving surgery rate was up to 92% compared with an 8% total mastectomy rate. No surgical complications were reported. Conclusions: This study demonstrates that SBRT can be safely combined with NACT. Regarding the efficacy endpoints, this trial showed promising results in terms of pCR rate (36%) and breast-conserving rate (92%). The findings provide a strong rationale for extending the study into a phase 2 trial. In view of the absence of correlation between dose and pCR, and given that the data from dose level 3 met the statistical requirements, a dose of 25.5 Gy in 3 fractions should be used for the phase 2 trial.

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Early-Stage Breast Cancer Treated With 3-Week Accelerated Whole-Breast Radiation Therapy and Concomitant Boost

Purpose: To report early outcomes of accelerated whole-breast radiation therapy with concomitant boost. Methods and Materials: This is a prospective, institutional review board-approved study. Eligibility included stage TisN0, T1N0, and T2N0 breast cancer. Patients receiving adjuvant chemotherapy were ineligible. The whole breast received 40.5 Gy in 2.7-Gy fractions with a concomitant lumpectomy boost of 4.5 Gy in 0.3-Gy fractions. Total dose to the lumpectomy site was 45 Gy in 15 fractions over 19 days. Results: Between October 2004 and December 2010, 160 patients were treated; stage distribution was as follows: TisN0, n=63; T1N0, n=88; and T2N0, n=9. With a median follow-up of 3.5 years (range, 1.5-7.8 years) the 5-year overall survival and disease-free survival rates were 90% (95% confidence interval [CI] 0.84-0.94) and 97% (95% CI 0.93-0.99), respectively. Five-year local relapse-free survival was 99% (95% CI 0.96-0.99). Acute National Cancer Institute/Common Toxicity Criteria grade 1 and 2 skin toxicity was observed in 70% and 5%, respectively. Among the patients with ≥2-year follow-up no toxicity higher than grade 2 on the Late Effects in Normal Tissues–Subjective, Objective, Management, and Analytic scale was observed. Review of the radiation therapy dose–volume histogram noted that ≥95% of the prescribed dose encompassed the lumpectomy target volume in >95% of plans. The median dose received by the heart D{sub 05} was 215 cGy, and median lung V{sub 20} was 7.6%. Conclusions: The prescribed accelerated schedule of whole-breast radiation therapy with concomitant boost can be administered, achieving acceptable dose distribution. With follow-up to date, the results are encouraging and suggest minimal side effects and excellent local control.

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Preoperative Short-Course Concurrent Chemoradiation Therapy Followed by Delayed Surgery for Locally Advanced Rectal Cancer: A Phase 2 Multicenter Study (KROG 10-01)

Purpose: A prospective phase 2 multicenter trial was performed to investigate the efficacy and safety of preoperative short-course concurrent chemoradiation therapy (CRT) followed by delayed surgery for patients with locally advanced rectal cancer. Methods and Materials: Seventy-three patients with cT3-4 rectal cancer were enrolled. Radiation therapy of 25 Gy in 5 fractions was delivered over 5 consecutive days using helical tomotherapy. Concurrent chemotherapy was administered on the same 5 days with intravenous bolus injection of 5-fluorouracil (400 mg/m{sup 2}/day) and leucovorin (20 mg/m{sup 2}/day). After 4 to 8 weeks, total mesorectal excision was performed. The primary endpoint was the pathologic downstaging (ypStage 0-I) rate, and secondary endpoints included tumor regression grade, tumor volume reduction rate, and toxicity. Results: Seventy-one patients completed the planned preoperative CRT and surgery. Downstaging occurred in 20 (28.2%) patients, including 1 (1.4%) with a pathologic complete response. Favorable tumor regression (grade 4-3) was observed in 4 (5.6%) patients, and the mean tumor volume reduction rate was 62.5 ± 21.3%. Severe (grade ≥3) treatment toxicities were reported in 27 (38%) patients from CRT until 3 months after surgery. Conclusions: Preoperative short-course concurrent CRT followed by delayed surgery for patients with locally advanced rectal cancer demonstrated poor pathologic responses compared with conventional long-course CRT, and it yielded considerable toxicities despite the use of an advanced radiation therapy technique.

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Use of 4-Dimensional Computed Tomography-Based Ventilation Imaging to Correlate Lung Dose and Function With Clinical Outcomes

Purpose: Four-dimensional computed tomography (4DCT)-based ventilation is an emerging imaging modality that can be used in the thoracic treatment planning process. The clinical benefit of using ventilation images in radiation treatment plans remains to be tested. The purpose of the current work was to test the potential benefit of using ventilation in treatment planning by evaluating whether dose to highly ventilated regions of the lung resulted in increased incidence of clinical toxicity. Methods and Materials: Pretreatment 4DCT data were used to compute pretreatment ventilation images for 96 lung cancer patients. Ventilation images were calculated using 4DCT data, deformable image registration, and a density-change based algorithm. Dose–volume and ventilation-based dose function metrics were computed for each patient. The ability of the dose–volume and ventilation-based dose–function metrics to predict for severe (grade 3+) radiation pneumonitis was assessed using logistic regression analysis, area under the curve (AUC) metrics, and bootstrap methods. Results: A specific patient example is presented that demonstrates how incorporating ventilation-based functional information can help separate patients with and without toxicity. The logistic regression significance values were all lower for the dose–function metrics (range P=.093-.250) than for their dose–volume equivalents (range, P=.331-.580). The AUC values were all greater for the dose–function metrics (range, 0.569-0.620) than for their dose–volume equivalents (range, 0.500-0.544). Bootstrap results revealed an improvement in model fit using dose–function metrics compared to dose–volume metrics that approached significance (range, P=.118-.155). Conclusions: To our knowledge, this is the first study that attempts to correlate lung dose and 4DCT ventilation-based function to thoracic toxicity after radiation therapy. Although the results were not significant at the .05 level, our data suggests that incorporating ventilation-based functional imaging can improve prediction for radiation pneumonitis. We present an important first step toward validating the use of 4DCT-based ventilation imaging in thoracic treatment planning.

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Stereotactic Body Radiation Therapy for Locally Advanced and Borderline Resectable Pancreatic Cancer Is Effective and Well Tolerated

Purpose: Stereotactic body radiation therapy (SBRT) provides high rates of local control (LC) and margin-negative (R0) resections for locally advanced pancreatic cancer (LAPC) and borderline resectable pancreatic cancer (BRPC), respectively, with minimal toxicity. Methods and Materials: A single-institution retrospective review was performed for patients with nonmetastatic pancreatic cancer treated with induction chemotherapy followed by SBRT. SBRT was delivered over 5 consecutive fractions using a dose painting technique including 7-10 Gy/fraction to the region of vessel abutment or encasement and 5-6 Gy/fraction to the remainder of the tumor. Restaging scans were performed at 4 weeks, and resectable patients were considered for resection. The primary endpoints were overall survival (OS) and progression-free survival (PFS). Results: Seventy-three patients were evaluated, with a median follow-up time of 10.5 months. Median doses of 35 Gy and 25 Gy were delivered to the region of vessel involvement and the remainder of the tumor, respectively. Thirty-two BRPC patients (56.1%) underwent surgery, with 31 undergoing an R0 resection (96.9%). The median OS, 1-year OS, median PFS, and 1-year PFS for BRPC versus LAPC patients was 16.4 months versus 15 months, 72.2% versus 68.1%, 9.7 versus 9.8 months, and 42.8% versus 41%, respectively (all P>.10). BRPC patients who underwent R0 resection had improved median OS (19.3 vs 12.3 months; P=.03), 1-year OS (84.2% vs 58.3%; P=.03), and 1-year PFS (56.5% vs 25.0%; P<.0001), respectively, compared with all nonsurgical patients. The 1-year LC in nonsurgical patients was 81%. We did not observe acute grade ≥3 toxicity, and late grade ≥3 toxicity was minimal (5.3%). Conclusions: SBRT safely facilitates margin-negative resection in patients with BRPC pancreatic cancer while maintaining a high rate of LC in unresectable patients. These data support the expanded implementation of SBRT for pancreatic cancer.

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The Impact of Tumor Size on Outcomes After Stereotactic Body Radiation Therapy for Medically Inoperable Early-Stage Non-Small Cell Lung Cancer

Purpose: Stereotactic body radiation therapy for medically inoperable early-stage non-small cell lung cancer (NSCLC) offers excellent control rates. Most published series deal mainly with small (usually <4 cm), peripheral, solitary tumors. Larger tumors are associated with poorer outcomes (ie, lower control rates, higher toxicity) when treated with conventional RT. It is unclear whether SBRT is sufficiently potent to control these larger tumors. We therefore evaluated and examined the influence of tumor size on treatment outcomes after SBRT. Methods and Materials: Between October 2004 and October 2010, 185 medically inoperable patients with early (T1-T2N0M0) NSCLC were treated on a prospective research ethics board-approved single-institution protocol. Prescription doses were risk-adapted based on tumor size and location. Follow-up included prospective assessment of toxicity (as per Common Terminology Criteria for Adverse Events, version 3.0) and serial computed tomography scans. Patterns of failure, toxicity, and survival outcomes were calculated using Kaplan-Meier method, and the significance of tumor size (diameter, volume) with respect to patient, treatment, and tumor factors was tested. Results: Median follow-up was 15.2 months. Tumor size was not associated with local failure but was associated with regional failure (P=.011) and distant failure (P=.021). Poorer overall survival (P=.001), disease-free survival (P=.001), and cause-specific survival (P=.005) were also significantly associated with tumor size (with tumor volume more significant than diameter). Gross tumor volume and planning target volume were significantly associated with grade 2 or worse radiation pneumonitis. However, overall rates of grade ≥3 pneumonitis were low and not significantly affected by tumor or target size. Conclusions: Currently employed stereotactic body radiation therapy dose regimens can provide safe effective local therapy even for larger solitary NSCLC tumors (up to 5.7 cm in tumor diameter or 100 cm{sup 3} in tumor volume) but are associated with more nonlocal failures as well as poorer survival. These observations suggest these patients may benefit from more extensive staging or consideration of adjuvant therapy.

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Impact of Dose to the Bladder Trigone on Long-Term Urinary Function After High-Dose Intensity Modulated Radiation Therapy for Localized Prostate Cancer

Purpose: To determine the potential association between genitourinary (GU) toxicity and planning dose–volume parameters for GU pelvic structures after high-dose intensity modulated radiation therapy in localized prostate cancer patients. Methods and Materials: A total of 268 patients who underwent intensity modulated radiation therapy to a prescribed dose of 86.4 Gy in 48 fractions during June 2004-December 2008 were evaluated with the International Prostate Symptom Score (IPSS) questionnaire. Dose–volume histograms of the whole bladder, bladder wall, urethra, and bladder trigone were analyzed. The primary endpoint for GU toxicity was an IPSS sum increase ≥10 points over baseline. Univariate and multivariate analyses were done by the Kaplan-Meier method and Cox proportional hazard models, respectively. Results: Median follow-up was 5 years (range, 3-7.7 years). Thirty-nine patients experienced an IPSS sum increase ≥10 during follow-up; 84% remained event free at 5 years. After univariate analysis, lower baseline IPSS sum (P=.006), the V90 of the trigone (P=.006), and the maximal dose to the trigone (P=.003) were significantly associated with an IPSS sum increase ≥10. After multivariate analysis, lower baseline IPSS sum (P=.009) and increased maximal dose to the trigone (P=.005) remained significantly associated. Seventy-two patients had both a lower baseline IPSS sum and a higher maximal dose to the trigone and were defined as high risk, and 68 patients had both a higher baseline IPSS sum and a lower maximal dose to the trigone and were defined as low risk for development of an IPSS sum increase ≥10. Twenty-one of 72 high-risk patients (29%) and 5 of 68 low-risk patients (7%) experienced an IPSS sum increase ≥10 (P=.001; odds ratio 5.19). Conclusions: The application of hot spots to the bladder trigone was significantly associated with relevant changes in IPSS during follow-up. Reduction of radiation dose to the lower bladder and specifically the bladder trigone seems to be associated with a reduction in late GU toxicity.

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Five-Year Outcomes from 3 Prospective Trials of Image-Guided Proton Therapy for Prostate Cancer

Purpose: To report 5-year clinical outcomes of 3 prospective trials of image-guided proton therapy for prostate cancer. Methods and Materials: A total of 211 prostate cancer patients (89 low-risk, 82 intermediate-risk, and 40 high-risk) were treated in institutional review board-approved trials of 78 cobalt gray equivalent (CGE) in 39 fractions for low-risk disease, 78 to 82 CGE for intermediate-risk disease, and 78 CGE with concomitant docetaxel therapy followed by androgen deprivation therapy for high-risk disease. Toxicities were graded according to Common Terminology Criteria for Adverse Events (CTCAE), version 3.0. Median follow-up was 5.2 years. Results: Five-year rates of biochemical and clinical freedom from disease progression were 99%, 99%, and 76% in low-, intermediate-, and high-risk patients, respectively. Actuarial 5-year rates of late CTCAE, version 3.0 (or version 4.0) grade 3 gastrointestinal and urologic toxicity were 1.0% (0.5%) and 5.4% (1.0%), respectively. Median pretreatment scores and International Prostate Symptom Scores at >4 years posttreatment were 8 and 7, 6 and 6, and 9 and 8, respectively, among the low-, intermediate-, and high-risk patients. There were no significant changes between median pretreatment summary scores and Expanded Prostate Cancer Index Composite scores at >4 years for bowel, urinary irritative and/or obstructive, and urinary continence. Conclusions: Five-year clinical outcomes with image-guided proton therapy included extremely high efficacy, minimal physician-assessed toxicity, and excellent patient-reported outcomes. Further follow-up and a larger patient experience are necessary to confirm these favorable outcomes.

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Phase 2 Study of Combined Sorafenib and Radiation Therapy in Patients With Advanced Hepatocellular Carcinoma

Purpose: This phase 2 study evaluated the efficacy of radiation therapy (RT) with concurrent and sequential sorafenib therapy in patients with unresectable hepatocellular carcinoma (HCC). Methods and Materials: Forty patients with unresectable HCC unfit for transarterial chemoembolization were treated with RT with concurrent and sequential sorafenib. Sorafenib was administered from the commencement of RT at a dose of 400 mg twice daily and continued to clinical or radiologic progression, unacceptable adverse events, or death. All patients had underlying Child-Pugh A cirrhosis. The maximal tumor diameter ranged from 3.0 cm to 15.5 cm. Coexisting portal vein thrombosis was found in 24 patients and was irradiated simultaneously. The cumulative RT dose ranged from 40 Gy to 60 Gy (median, 50 Gy). Image studies were done 1 month after RT and then every 3 months thereafter. Results: Thirty-three (83%) completed the allocated RT. During RT, the incidence of hand-foot skin reactions ≥ grade 2 and diarrhea were 37.5% and 25%, respectively, and 35% of patients had hepatic toxicities grade ≥2. Twenty-two (55.0%) patients achieved complete or partial remission at the initial assessment, and 18 (45%) had stable or progressive disease. The 2-year overall survival and infield progression-free survival (IFPS) were 32% and 39%, respectively. A Cancer of the Liver Italian Program (CLIP) score ≥2 was associated with an inferior outcome in overall survival. Six patients (15%) developed treatment-related hepatic toxicity grade ≥3 during the sequential phase, and 3 of them were fatal. Conclusions: When RT and sorafenib therapy were combined in patients with unresectable HCC, the initial complete or partial response rate was 55% with a 2-year IFPS of 39%. A CLIP score ≥2 was associated with an inferior outcome in overall survival. Hepatic toxicities are a major determinant of the safety; the combination should be used with caution and needs further investigation.

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Phase 1 Pharmacogenetic and Pharmacodynamic Study of Sorafenib With Concurrent Radiation Therapy and Gemcitabine in Locally Advanced Unresectable Pancreatic Cancer

Purpose: To define the safety, efficacy, and pharmacogenetic and pharmacodynamic effects of sorafenib with gemcitabine-based chemoradiotherapy (CRT) in locally advanced pancreatic cancer. Methods and Materials: Patients received gemcitabine 1000 mg/m{sup 2} intravenously weekly × 3 every 4 weeks per cycle for 1 cycle before CRT and continued for up to 4 cycles after CRT. Weekly gemcitabine 600 mg/m{sup 2} intravenously was given during concurrent intensity modulated radiation therapy of 50 Gy to gross tumor volume in 25 fractions. Sorafenib was dosed orally 400 mg twice daily until progression, except during CRT when it was escalated from 200 mg to 400 mg daily, and 400 mg twice daily. The maximum tolerated dose cohort was expanded to 15 patients. Correlative studies included dynamic contrast-enhanced MRI and angiogenesis genes polymorphisms (VEGF-A and VEGF-R2 single nucleotide polymorphisms). Results: Twenty-seven patients were enrolled. No dose-limiting toxicity occurred during induction gemcitabine/sorafenib followed by concurrent CRT. The most common grade 3/4 toxicities were fatigue, hematologic, and gastrointestinal. The maximum tolerated dose was sorafenib 400 mg twice daily. The median progression-free survival and overall survival for 25 evaluable patients were 10.6 and 12.6 months, respectively. The median overall survival for patients with VEGF-A -2578 AA, -1498 CC, and -1154 AA versus alternate genotypes was 21.6 versus 14.7 months. Dynamic contrast-enhanced MRI demonstrated higher baseline K{sup trans} in responding patients. Conclusions: Concurrent sorafenib with CRT had modest clinical activity with increased gastrointestinal toxicity in localized unresectable pancreatic cancer. Select VEGF-A/VEGF-R2 genotypes were associated with favorable survival.

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Stereotactic Radiation Therapy for Benign Meningioma: Long-Term Outcome in 318 Patients

Purpose: To investigate the long-term outcome of stereotactic-based radiation therapy in a large cohort of patients with benign intracranial meningiomas. Methods and Materials: Between 1997 and 2010, 318 patients with histologically confirmed (44.7%; previous surgery) or imaging-defined (55.3%) benign meningiomas were treated with either fractionated stereotactic radiation therapy (79.6%), hypofractionated stereotactic radiation therapy (15.4%), or stereotactic radiosurgery (5.0%), depending on tumor size and location. Local control (LC), overall survival (OS), cause-specific survival (CSS), prognostic factors, and toxicity were analyzed. Results: The median follow-up was 50 months (range, 12-167 months). Local control, OS, and CSS at 5 years were 92.9%, 88.7%, and 97.2%, and at 10 years they were 87.5%, 74.1%, and 97.2%, respectively. In the multivariate analysis, tumor location (P=.029) and age >66 years (P=.031) were predictors of LC and OS, respectively. Worsening of pre-existing neurologic symptoms immediately after radiation therapy occurred in up to 2%. Clinically significant acute toxicity (grade 3°) occurred in 3%. Only grade 1-2 late toxicity was observed in 12%, whereas no new neurologic deficits or treatment-related mortality were encountered. Conclusions: Patients with benign meningiomas predominantly treated with standard fractionated stereotactic radiation therapy with narrow margins enjoy excellent LC and CSS, with minimal long-term morbidity.

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Definitive Chemoradiation Therapy With Docetaxel, Cisplatin, and 5-Fluorouracil (DCF-R) in Advanced Esophageal Cancer: A Phase 2 Trial (KDOG 0501-P2)

Purpose: A previous phase 1 study suggested that definitive chemoradiation therapy with docetaxel, cisplatin, and 5-fluorouracil (DCF-R) is tolerable and active in patients with advanced esophageal cancer (AEC). This phase 2 study was designed to confirm the efficacy and toxicity of DCF-R in AEC. Methods and Materials: Patients with previously untreated thoracic AEC who had T4 tumors or M1 lymph node metastasis (M1 LYM), or both, received intravenous infusions of docetaxel (35 mg/m{sup 2}) and cisplatin (40 mg/m{sup 2}) on day 1 and a continuous intravenous infusion of 5-fluorouracil (400 mg/m{sup 2}/day) on days 1 to 5, every 2 weeks, plus concurrent radiation. The total radiation dose was initially 61.2 Gy but was lowered to multiple-field irradiation with 50.4 Gy to decrease esophagitis and late toxicity. Consequently, the number of cycles of DCF administered during radiation therapy was reduced from 4 to 3. The primary endpoint was the clinical complete response (cCR) rate. Results: Characteristics of the 42 subjects were: median age, 62 years; performance status, 0 in 14, 1 in 25, 2 in 3; TNM classification, T4M0 in 20, non-T4M1LYM in 12, T4M1LYM in 10; total scheduled radiation dose: 61.2 Gy in 12, 50.4 Gy in 30. The cCR rate was 52.4% (95% confidence interval [CI]: 37.3%-67.5%) overall, 33.3% in the 61.2-Gy group, and 60.0% in the 50.4-Gy group. The median progression-free survival was 11.1 months, and the median survival was 29.0 months with a survival rate of 43.9% at 3 years. Grade 3 or higher major toxicity consisted of leukopenia (71.4%), neutropenia (57.2%), anemia (16.7%), febrile neutropenia (38.1%), anorexia (31.0%), and esophagitis (28.6%). Conclusions: DCF-R frequently caused myelosuppression and esophagitis but was highly active and suggested to be a promising regimen in AEC. On the basis of efficacy and safety, a radiation dose of 50.4 Gy is recommended for further studies of DCF-R.

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30 Gy or 34 Gy? Comparing 2 Single-Fraction SBRT Dose Schedules for Stage I Medically Inoperable Non-Small Cell Lung Cancer

Purpose: To review outcomes of 2 single-fraction lung stereotactic body radiation therapy (SBRT) schedules used for medically inoperable early stage lung cancer. Methods and Materials: Patients in our institution have been treated on and off protocols using single-fraction SBRT (30 Gy and 34 Gy, respectively). All patients had node-negative lung cancer measuring ≤5 cm and lying ≥2 cm beyond the trachea-bronchial tree and were treated on a Novalis/BrainLAB system with the ExactTrac positioning system for daily image guidance. Results: For the interval from 2009 to 2012, 80 patients with 82 lesions were treated with single-fraction lung SBRT. Fifty-five patients (69%) and 25 patients (31%) received 30 Gy and 34 Gy, respectively. In a comparison of 30 Gy and 34 Gy cohorts, patient and tumor characteristics were balanced and median follow-up in months was 18.7 and 17.8, respectively. The average heterogeneity-corrected mean doses to the target were 33.75 Gy and 37.94 Gy for the 30-Gy and 34-Gy prescriptions, respectively. Comparing 30-Gy and 34-Gy cohorts, 92.7% and 84.0% of patients, respectively, experienced no toxicity (P was not significant), and had neither grade 3 nor higher toxicities. For the 30-Gy and 34-Gy patients, rates of 1-year local failure, overall survival, and lung cancer-specific mortality were 2.0% versus 13.8%, 75.0% versus 64.0%, and 2. 1% versus 16.0%, respectively (P values for differences were not significant). Conclusions: This is the largest single-fraction lung SBRT series yet reported. and it confirms the safety, efficacy, and minimal toxicity of this schedule for inoperable early stage lung cancer.

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A Phase 2 Trial of Radiation Therapy With Concurrent Paclitaxel Chemotherapy After Surgery in Patients With High-Risk Endometrial Cancer: A Korean Gynecologic Oncologic Group Study

Purpose: A phase 2 study was completed by the Korean Gynecologic Oncologic Group to evaluate the efficacy and toxicity of concurrent chemoradiation with weekly paclitaxel in patients with high-risk endometrial cancer. Methods and Materials: Pathologic requirements included endometrial endometrioid adenocarcinoma stages III and IV. Radiation therapy consisted of a total dose of 4500 to 5040 cGy in 5 fractions per week for 6 weeks. Paclitaxel 60 mg/m{sup 2} was administered once weekly for 5 weeks during radiation therapy. Results: Fifty-seven patients were enrolled between January 2006 and March 2008. The median follow-up time was 60.0 months (95% confidence interval [CI], 51.0-58.2). All grade 3/4 toxicities were hematologic and usually self-limited. There was no life-threatening toxicity. The cumulative incidence of intrapelvic recurrence sites was 1.9% (1/52), and the cumulative incidence of extrapelvic recurrence sites was 34.6% (18/52). The estimated 5-year disease-free and overall survival rates were 63.5% (95% CI, 50.4-76.5) and 82.7% (95% CI, 72.4-92.9), respectively. Conclusions: Concurrent chemoradiation with weekly paclitaxel is well tolerated and seems to be effective for high-risk endometrioid endometrial cancers. This approach appears reasonable to be tested for efficacy in a prospective, randomized controlled study.

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Phase 2 Study of Concurrent Cetuximab Plus Definitive Thoracic Radiation Therapy Followed by Consolidation Docetaxel Plus Cetuximab in Poor Prognosis or Elderly Patients With Locally Advanced Non-Small Cell Lung Cancer

Background: Recursive partitioning analysis has shown that Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) ≥2, male sex, and age ≥70 years are prognostic of poor outcome in locally advanced non-small cell lung cancer (LA-NSCLC) patients. Concurrent chemoradiation therapy (CRT) improves survival, but toxicity is a concern in this frail patient cohort. We therefore opened this trial of concurrent definitive thoracic radiation therapy (XRT) and cetuximab, followed by consolidation docetaxel plus cetuximab. Methods and Materials: Eligible patients had pathologically proven, unresectable LA-NSCLC (stage IIA-“dry” IIIB). They had ECOG PS 2 or weight loss ≥5% in 3 months or were aged ≥70 years. The primary objective was progression-free survival (PFS). Secondary objectives included overall survival (OS) and overall response rate (ORR). Results: From May 2008 to November 2010, a total of 32 patients were evaluated in our single-institution, institutional review board–approved prospective clinical trial. Three patients were screen failures and 2 more withdrew consent before treatment, leaving 27 evaluable patients. One was removed because of poor therapy compliance, and 2 were taken off trial because of grade 3 cetuximab-related toxicities but were followed up under intent-to-treat analysis. The median follow-up and OS were 10.5 months. The median PFS was 7.5 months. The ORR was 59.3%. Eight early/sudden deaths were reported. Upon review, 6 patients developed severe pulmonary complications. Conclusions: Patients enrolled in this trial had improved OS compared with poor-PS historical controls (10.5 vs 6.4 months) and comparable OS to good-PS historical controls (10.5 vs 11.9 months) treated with XRT alone. However, pulmonary toxicity is a concern. Consolidative cetuximab/docetaxel, in conjunction with high-dose radiation therapy, is a putative cause.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

The Modern Role of Radiation Therapy in Treating Advanced-Stage Retinoblastoma: Long-Term Outcomes and Racial Differences

Purpose/Objective(s): To evaluate the effects of various patient characteristics and radiation therapy treatment variables on outcomes in advanced-stage retinoblastoma. Methods and Materials: This was a retrospective review of 41 eyes of 30 patients treated with external beam radiation therapy between June 1, 1992, and March 31, 2012, with a median follow-up time of 133 months (11 years). Outcome measures included overall survival, progression-free survival, local control, eye preservation rate, and toxicity. Results: Over 90% of the eyes were stage V. Definitive external beam radiation therapy (EBRT) was delivered in 43.9% of eyes, adjuvant EBRT in 22% of eyes, and second-line/salvage EBRT in 34.1% of eyes. A relative lens sparing (RLS) technique was used in 68.3% of eyes and modified lens sparing (MLS) in 24.4% of eyes. Three eyes were treated with other techniques. Doses ≥45 Gy were used in 68.3% of eyes. Chemotherapy was a component of treatment in 53.7% of eyes. The 10-year overall survival was 87.7%, progression-free survival was 80.5%, and local control was 87.8%. White patients had significantly better overall survival than did African-American patients in univariate analysis (hazard ratio 0.09; 95% confidence interval 0.01-0.84; P=.035). Toxicity was seen in 68.3% of eyes, including 24.3% with isolated acute dermatitis. Conclusions: External beam radiation therapy continues to be an effective treatment modality for advanced retinoblastoma, achieving excellent long-term local control and survival with low rates of treatment-related toxicity and secondary malignancy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗