Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “kaplan”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9

Outcomes in Women Treated With MammoSite Brachytherapy or Whole Breast Irradiation Stratified by ASTRO Accelerated Partial Breast Irradiation Consensus Statement Groups

Purpose: The American Society for Radiation Oncology published a Consensus Statement for accelerated partial breast irradiation identifying three groups: Suitable, Cautionary, and Unsuitable. The objective of this study was to compare oncologic outcomes in women treated with MammoSite brachytherapy (MB) vs. whole breast irradiation (WBI) after stratification into Statement groups. Methods: Eligible women had invasive carcinoma or ductal carcinoma in situ (DCIS) {<=}3 cm, and {<=}3 lymph nodes positive. Women were stratified by radiation modality and Statement groups. Survival analysis methods including Kaplan-Meier estimation, Cox regression, and competing risks analysis were used to assess overall survival (OS), disease-free survival (DFS), time to local failure (TTLF), and tumor bed failure (TBF). Results: A total of 459 (183 MB and 276 WBI) patients were treated from 2002 to 2009. After a median follow-up of 45 months, we found no statistical differences by stratification group or radiation modality with regard to OS and DFS. At 4 years TTLF or TBF were not statistically different between the cohorts. Univariate analysis in the MB cohort revealed that nodal positivity (pN1 vs. pN0) was related to TTLF (hazard ratio 6.39, p = 0.02). There was a suggestion that DCIS histology had an increased risk of failure when compared with invasive ductal carcinoma (hazard ratio 3.57, p = 0.06). Conclusions: MB and WBI patients stratified by Statement groups seem to combine women who will have similar outcomes regardless of radiation modality. Although outcomes were similar, we remain guarded in overinterpretation of these preliminary results until further analysis and long-term follow-up data become available. Caution should be used in treating women with DCIS or pN1 disease with MB.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Fibroblast Growth Factor 2-A Predictor of Outcome for Patients Irradiated for Stage II-III Non-Small-Cell Lung Cancer

Purpose: The prognostic value of the tumor cell expression of the fibroblast growth factor 2 (FGF-2) in patients with non-small-cell lung cancer (NSCLC) is unclear. The present study investigated the effect of tumor cell expression of FGF-2 on the outcome of 60 patients irradiated for Stage II-III NSCLC. Methods and Materials: The effect of FGF-2 expression and 13 additional factors on locoregional control (LRC), metastasis-free survival (MFS), and overall survival (OS) were retrospectively evaluated. These additional factors included age, gender, Karnofsky performance status, histologic type, histologic grade, T and N category, American Joint Committee on Cancer stage, surgery, chemotherapy, pack-years, smoking during radiotherapy, and hemoglobin during radiotherapy. Locoregional failure was identified by endoscopy or computed tomography. Univariate analyses were performed with the Kaplan-Meier method and the Wilcoxon test and multivariate analyses with the Cox proportional hazard model. Results: On univariate analysis, improved LRC was associated with surgery (p = .017), greater hemoglobin levels (p = .036), and FGF-2 negativity (p <.001). On multivariate analysis of LRC, surgery (relative risk [RR], 2.44; p = .037), and FGF-2 expression (RR, 5.06; p <.001) maintained significance. On univariate analysis, improved MFS was associated with squamous cell carcinoma (p = .020), greater hemoglobin levels (p = .007), and FGF-2 negativity (p = .001). On multivariate analysis of MFS, the hemoglobin levels (RR, 2.65; p = .019) and FGF-2 expression (RR, 3.05; p = .004) were significant. On univariate analysis, improved OS was associated with a lower N category (p = .048), greater hemoglobin levels (p <.001), and FGF-2 negativity (p <.001). On multivariate analysis of OS, greater hemoglobin levels (RR, 4.62; p = .002) and FGF-2 expression (RR, 3.25; p = .002) maintained significance. Conclusions: Tumor cell expression of FGF-2 appeared to be an independent negative predictor of LRC, MFS, and OS.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

High-Dose-Rate Brachytherapy Boost for Prostate Cancer: Comparison of Two Different Fractionation Schemes

Purpose: This is a retrospective study comparing our experience with high-dose-rate (HDR) brachytherapy boost for prostate cancer, using two different fractionation schemes, 600 cGy Multiplication-Sign 3 fractions (patient group 1) and 950 cGy Multiplication-Sign 2 fractions (patient group 2). Methods and Materials: A total of 165 patients were treated for prostate cancer using external beam radiation therapy up to a dose of 45 Gy, followed by an HDR brachytherapy prostate radiation boost. Between July 1997 and Nov 1999, 64 patients were treated with an HDR boost of 600 cGy Multiplication-Sign 3 fractions; and between June 2000 and Nov 2005, 101 patients were treated with an HDR boost of 950 cGy Multiplication-Sign 2 fractions. All but 9 patients had at least one of the following risk features: pretreatment prostate-specific antigen (PSA) level >10, a Gleason score {>=}7, and/or clinical stage T3 disease. Results: Median follow-up was 105 months for group 1 and 43 months for group 2. Patients in group 2 had a greater number of high-risk features than group 1 (p = 0.02). Adjusted for comparable follow-up, there was no difference in biochemical no-evidence-of-disease (bNED) rate between the two fractionation scheme approaches, with 5-year Kaplan-Meier estimates of 93.5% in group 1 and 87.3% in group 2 (p = 0.19). The 5-year estimates of progression-free survival were 86% for group 1 and 83% for group 2 (p = 0.53). Among high-risk patients, there were no differences in bNED or PFS rate due to fractionation. Conclusions: Results were excellent for both groups. Adjusted for comparable follow-up, no differences were found between groups.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Dose-Painted Intensity-Modulated Radiation Therapy for Anal Cancer: A Multi-Institutional Report of Acute Toxicity and Response to Therapy

Purpose: Chemoradiation for anal cancer yields effective tumor control, but is associated with significant acute toxicity. We report our multi-institutional experience using dose-painted IMRT (DP-IMRT). Patients and Methods: Between August 2005 and May 2009, 43 patients were treated with DP-IMRT and concurrent chemotherapy for biopsy-proven, squamous cell carcinoma of the anal canal at two academic medical centers. DP-IMRT was prescribed as follows: T2N0: 42 Gy, 1.5 Gy/fraction (fx) to elective nodal planning target volume (PTV) and 50.4 Gy, 1.8 Gy/fx to anal tumor PTV; T3-4N0-3: 45 Gy, 1.5 Gy/fx to elective nodal PTV, and 54 Gy, 1.8 Gy/fx to the anal tumor and metastatic nodal PTV >3 cm with 50.4 Gy, 1.68 Gy/fx to nodal PTVs {<=}3 cm in size. Acute and late toxicity was reported by the treating physician. Actuarial analysis was performed using the Kaplan-Meier method. Results: Median age was 58 years; 67% female; 16% Stage I, 37% II; 42% III; 5% IV. Fourteen patients were immunocompromised: 21% HIV-positive and 12% on chronic immunosuppression. Median follow-up was 24 months (range, 0.6-43.5 months). Sixty percent completed chemoradiation without treatment interruption; median duration of treatment interruption was 2 days (range, 2-24 days). Acute Grade 3+ toxicity included: hematologic 51%, dermatologic 10%, gastrointestinal 7%, and genitourinary 7%. Two-year local control, overall survival, colostomy-free survival, and metastasis-free survival were 95%, 94%, 90%, and 92%, respectively. Conclusions: Dose-painted IMRT appears effective and well-tolerated as part of a chemoradiation therapy regimen for the treatment of anal canal cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Simultaneous Integrated Boost Using Intensity-Modulated Radiotherapy Compared With Conventional Radiotherapy in Patients Treated With Concurrent Carboplatin and 5-Fluorouracil for Locally Advanced Oropharyngeal Carcinoma

Purpose: To compare, in a retrospective study, the toxicity and efficacy of simultaneous integrated boost using intensity-modulated radiotherapy (IMRT) vs. conventional radiotherapy (CRT) in patients treated with concomitant carboplatin and 5-fluorouracil for locally advanced oropharyngeal cancer. Methods and Materials: Between January 2000 and December 2007, 249 patients were treated with definitive chemoradiation. One hundred patients had 70 Gy in 33 fractions using IMRT, and 149 received CRT at 70 Gy in 35 fractions. Overall survival, disease-free survival, and locoregional control were estimated using the Kaplan-Meier method. Results: Median follow-up was 42 months. Three-year actuarial rates for locoregional control, disease-free survival, and overall survival were 95.1% vs. 84.4% (p = 0.005), 85.3% vs. 69.3% (p = 0.001), and 92.1% vs. 75.2% (p < 0.001) for IMRT and CRT, respectively. The benefit of the radiotherapy regimen on outcomes was also observed with a Cox multivariate analysis. Intensity-modulated radiotherapy was associated with less acute dermatitis and less xerostomia at 6, 12, 24, and 36 months. Conclusions: This study suggests that simultaneous integrated boost using IMRT is associated with favorable locoregional control and survival rates with less xerostomia and acute dermatitis than CRT when both are given concurrently with chemotherapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Declining Use of Radiotherapy in Stage I and II Hodgkin's Disease and Its Effect on Survival and Secondary Malignancies

Purpose: Concerns regarding long-term toxicities have led some to withhold radiotherapy (RT) for the treatment of Stage I and II Hodgkin's disease (HD). The present study was undertaken to assess the use of RT for HD and its effect on overall survival and the development of secondary malignancies. Methods and Materials: The present study included data from the Surveillance, Epidemiology, and End Results database from patients aged {>=}20 years who had been diagnosed with Stage I or II HD between 1988 and 2006. Overall survival was estimated using the Kaplan-Meier method, and the Cox multivariate regression model was used to analyze trends. Results: A total of 12,247 patients were selected, and 51.5% had received RT. The median follow-up for the present cohort was 4.9 years, with 21% of the cohort having >10 years of follow-up. Between 1988 and 1991, 62.9% had undergone RT, but between 2004 and 2006, only 43.7% had undergone RT (p < .001). The 5-year overall survival rate was 76% for patients who had not received RT and 87% for those who had (p < .001). The hazard ratio adjusted for other variables in the regression model showed that patients who had not undergone RT (hazard ratio, 1.72; 95% confidence interval, 1.72-2.02) was associated with significantly worse survival compared with patients who had received RT. The actuarial rate of developing a second malignancy was 14.6% vs. 15.0% at 15 years for those who had and had not undergone RT, respectively (p = .089). Conclusions: The present study is one of the largest studies to examine the role of RT for Stage I and II HD. Our results revealed a survival benefit with the addition of RT with no increase in the development of secondary malignancies compared with patients who had not received RT. Furthermore, the present nationwide study revealed a >20% absolute decrease in the use of RT from 1988 to 2006.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Stage-to-Stage Comparison of Preoperative and Postoperative Chemoradiotherapy for T3 Mid or Distal Rectal Cancer

Purpose: To investigate, in a comparative analysis, the prognostic implications of postchemoradiotherapy (post-CRT) pathologic stage (ypStage) vs. postoperative pathologic stage (pStage) in rectal cancer. Methods and Materials: Between May 2001 and December 2006, 487 patients with T3 mid or distal rectal cancer were analyzed retrospectively. Concurrent CRT was administered preoperatively (n = 364, 74.7%) or postoperatively (n = 123, 25.3%). The radiation dose was 50.4 Gy in 28 fractions. All patients underwent a total mesorectal excision and received adjuvant chemotherapy. Disease-free survival (DFS) was estimated using the Kaplan-Meier method. Differences in DFS, stratified by ypStage and pStage, were compared using the log-rank test. Results: For surviving patients, the median follow-up period was 68 months (range, 12-105 months). The 5-year local recurrence-free survival rate was not different, at 95.3% and 92.1% in preoperative and postoperative CRT groups, respectively (p = 0.402), but the 5-year distant metastasis-free survival rate was significantly different, at 81.6% (preoperative CRT) vs. 65.4% (postoperative CRT; p = 0.001). The 5-year DFS rate of 78.8% in the preoperative CRT group was significantly better than the 63.0% rate in the postoperative CRT group (p = 0.002). Post-CRT pathologic Stage 0-I occurred in 42.6% (155 of 364) of the patients with preoperative CRT. The 5-year DFS rates were 90.2% (ypStage 0-I), 83.5% (ypStage II), 77.3% (pStage II), 58.6% (ypStage III), and 54.7% (pStage III). The DFS rate of ypStage 0-I was significantly better than that of ypStage II or pStage II. Post-CRT pathologic Stage II and III had similar DFS, compared with pStage II and III, respectively. Conclusions: Disease-free survival predicted by each ypStage was similar to that predicted by the respective pStage. Improved DFS with preoperative vs. postoperative CRT was associated with the ypStage 0-I group that showed a similarly favorable outcome to pStage I rectal cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Multi-Institutional Analysis of Solitary Extramedullary Plasmacytoma of the Head and Neck Treated With Curative Radiotherapy

Purpose: The purpose of this study was to elucidate the efficacy and optimal method of radiotherapy in the management of solitary extramedullary plasmacytoma occurring in the head and neck regions (EMPHN). Methods and Materials: Sixty-seven patients (43 male and 24 female) diagnosed with EMPHN between 1983 and 2008 at 23 Japanese institutions were reviewed. The median patient age was 64 years (range, 12-83). The median dose administered was 50 Gy (range, 30-64 Gy). Survival data were calculated by the Kaplan-Meier method. Results: The median follow-up duration was 63 months. Major tumor sites were nasal or paranasal cavities in 36 (54%) patients, oropharynx or nasopharynx in 16 (23%) patients, orbita in 6 (9%) patients, and larynx in 3 (5%) patients. The 5- and 10-year local control rates were 95% and 87%, whereas the 5- and 10-year disease-free survival rates were 56% and 54%, respectively. There were 5 (7.5%), 12 (18%), and 8 (12%) patients who experienced local failure, distant metastasis, and progression to multiple myeloma, respectively. In total, 18 patients died, including 10 (15%) patients who died due to complications from EMPHN. The 5- and 10-year overall survival (OS) rates were 73% and 56%, respectively. Radiotherapy combined with surgery was identified as the lone significant prognostic factor for OS (p = 0.04), whereas age, gender, radiation dose, tumor size, and chemotherapy were not predictive. No patient experienced any severe acute morbidity. Conclusions: Radiotherapy was quite effective and safe for patients with EMPHN. Radiotherapy combined with surgery produced a better outcome according to survival rates. These findings require confirmation by further studies with larger numbers of patients with EMPHN.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Analysis of Pretreatment FDG-PET SUV Parameters in Head-and-Neck Cancer: Tumor SUV{sub mean} Has Superior Prognostic Value

Purpose: To evaluate the prognostic significance of different descriptive parameters in head-and-neck cancer patients undergoing pretreatment [F-18] fluoro-D-glucose-positron emission tomography (FDG-PET) imaging. Patients and Methods: Head-and-neck cancer patients who underwent FDG-PET before a course of curative intent radiotherapy were retrospectively analyzed. FDG-PET imaging parameters included maximum (SUV{sub max}), and mean (SUV{sub mean}) standard uptake values, and total lesion glycolysis (TLG). Tumors and lymph nodes were defined on co-registered axial computed tomography (CT) slices. SUV{sub max} and SUV{sub mean} were measured within these anatomic regions. The relationships between pretreatment SUV{sub max}, SUV{sub mean}, and TLG for the primary site and lymph nodes were assessed using a univariate analysis for disease-free survival (DFS), locoregional control (LRC), and distant metastasis-free survival (DMFS). Kaplan-Meier survival curves were generated and compared via the log-rank method. SUV data were analyzed as continuous variables. Results: A total of 88 patients was assessed. Two-year OS, LRC, DMFS, and DFS for the entire cohort were 85%, 78%, 81%, and 70%, respectively. Median SUV{sub max} for the primary tumor and lymph nodes was 15.4 and 12.2, respectively. Median SUV{sub mean} for the primary tumor and lymph nodes was 7 and 5.2, respectively. Median TLG was 770. Increasing pretreatment SUV{sub mean} of the primary tumor was associated with decreased disease-free survival (p = 0.01). Neither SUV{sub max} in the primary tumor or lymph nodes nor TLG was prognostic for any of the clinical endpoints. Patients with pretreatment tumor SUV{sub mean} that exceeded the median value (7) of the cohort demonstrated inferior 2-year DFS relative to patients with SUV{sub mean} {<=} the median value of the cohort, 58% vs. 82%, respectively, p = 0.03. Conclusion: Increasing SUV{sub mean} in the primary tumor was associated with inferior DFS. Although not routinely reported, pretreatment SUV{sub mean} may be a useful prognostic FDG-PET parameter and should be further evaluated prospectively.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Long-Term Outcomes From a Prospective Trial of Stereotactic Body Radiotherapy for Low-Risk Prostate Cancer

Purpose: Hypofractionated radiotherapy has an intrinsically different normal tissue and tumor radiobiology. The results of a prospective trial of stereotactic body radiotherapy (SBRT) for prostate cancer with long-term patient-reported toxicity and tumor control rates are presented. Methods and Materials: From 2003 through 2009, 67 patients with clinically localized low-risk prostate cancer were enrolled. Treatment consisted of 36.25 Gy in 5 fractions using SBRT with the CyberKnife as the delivery technology. No patient received hormone therapy. Patient self-reported bladder and rectal toxicities were graded on the Radiation Therapy Oncology Group scale (RTOG). Results: Median follow-up was 2.7 years. There were no grade 4 toxicities. Radiation Therapy Oncology Group Grade 3, 2, and 1 bladder toxicities were seen in 3% (2 patients), 5% (3 patients), and 23% (13 patients) respectively. Dysuria exacerbated by urologic instrumentation accounted for both patients with Grade 3 toxicity. Urinary incontinence, complete obstruction, or persistent hematuria was not observed. Rectal Grade 3, 2, and 1 toxicities were seen in 0, 2% (1 patient), and 12.5% (7 patients), respectively. Persistent rectal bleeding was not observed. Low-grade toxicities were substantially less frequent with QOD vs. QD dose regimen (p = 0.001 for gastrointestinal and p = 0.007 for genitourinary). There were two prostate-specific antigen (PSA), biopsy-proven failures with negative metastatic workup. Median PSA at follow-up was 0.5 {+-} 0.72 ng/mL. The 4-year Kaplan-Meier PSA relapse-free survival was 94% (95% confidence interval, 85%-102%). Conclusion: Significant late bladder and rectal toxicities from SBRT for prostate cancer are infrequent. PSA relapse-free survival compares favorably with other definitive treatments. The current evidence supports consideration of stereotactic body radiotherapy among the therapeutic options for localized prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

The Role of Pretreatment FDG-PET in Nasopharyngeal Carcinoma Treated With Intensity-Modulated Radiotherapy

Purpose: Pretreatment with 2- [{sup 18}F] fluorodeoxyglucose positron emission tomography ({sup 18}F-FDG-PET) was evaluated as a predictor of local failure-free survival (LFFS), disease-free survival (DFS), and overall survival (OS) in patients with nonkeratinizing nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT) alone or concurrently with chemotherapy (CCRT). Patients and Methods: Seventy-five M0 NPC patients who received FDG-PET before treatment were analyzed. The primary tumor FDG uptake was measured as the maximum standardized uptake value (SUVmax). The LFFS, DFS, and OS were calculated by the Kaplan-Meier method, and the differences were evaluated on log-rank test. The prognostic significance was assessed by univariate and multivariate analyses. Results: Eighteen patients received IMRT alone and 57 received CCRT. The mean SUVmax was significantly higher in 12 patients with locoregional or distant failure than in those without failure (p <0.001). On multivariate analysis, the SUVmax was the only significant variable for 5-year LFFS (p = 0.017) and DFS (p = 0.000) but not for OS (p = 0.065). Conclusion: SUVmax is a potential independent prognostic predictor of clinical outcomes in patients with nasopharyngeal carcinoma treated with IMRT alone or with CCRT. A high {sup 18}F-FDG uptake (SUVmax >5) indicates poor outcome in patients with NPC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Positron Emission Tomography/Computed Tomography-Guided Intensity-Modulated Radiotherapy for Limited-Stage Small-Cell Lung Cancer

Purpose: Omitting elective nodal irradiation from planning target volumes does not compromise outcomes in patients with non-small-cell lung cancer, but whether the same is true for those with limited-stage small-cell lung cancer (LS-SCLC) is unknown. Therefore, in the present study, we sought to determine the clinical outcomes and the frequency of elective nodal failure in patients with LS-SCLC staged using positron emission tomography/computed tomography and treated with involved-field intensity-modulated radiotherapy. Methods and Materials: Between 2005 and 2008, 60 patients with LS-SCLC at our institution underwent disease staging using positron emission tomography/computed tomography before treatment using an intensity-modulated radiotherapy plan in which elective nodal irradiation was intentionally omitted from the planning target volume (mode and median dose, 45 Gy in 30 fractions; range, 40.5 Gy in 27 fractions to 63.8 Gy in 35 fractions). In most cases, concurrent platinum-based chemotherapy was administered. We retrospectively reviewed the clinical outcomes to determine the overall survival, relapse-free survival, and failure patterns. Elective nodal failure was defined as recurrence in initially uninvolved hilar, mediastinal, or supraclavicular nodes. Survival was assessed using the Kaplan-Meier method. Results: The median age of the study patients at diagnosis was 63 years (range, 39-86). The median follow-up duration was 21 months (range, 4-58) in all patients and 26 months (range, 4-58) in the survivors. The 2-year actuarial overall survival and relapse-free survival rate were 58% and 43%, respectively. Of the 30 patients with recurrence, 23 had metastatic disease and 7 had locoregional failure. We observed only one isolated elective nodal failure. Conclusions: To our knowledge, this is the first study to examine the outcomes in patients with LS-SCLC staged with positron emission tomography/computed tomography and treated with definitive intensity-modulated radiotherapy. In these patients, elective nodal irradiation can be safely omitted from the planning target volume for the purposes of dose escalation and toxicity reduction.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

The Impact of Post-Mastectomy Radiation Therapy on Male Breast Cancer Patients-A Case Series

Objective: To assess the impact of radiation management on male breast cancer (MBC) at London Regional Cancer Program (LRCP). Methods and Materials: Men with a diagnosis of breast cancer referred to LRCP were reviewed. The seventh American Joint Committee on Cancer staging system was used. Patients treated with and without post-mastectomy radiation therapy (PMRT) were analyzed. Disease-free survival (DFS) was defined as time duration from diagnosis to first recurrence. Overall survival (OS) was defined as time duration from pathologic diagnosis to death or last follow-up with any death defined as an event. Survival estimates were obtained using Kaplan-Meier methodology. Results: From January 1977 to December 2006, 81 men had invasive ductal carcinoma. The median age was 65 (range, 35-87 years). There were 15 Stage I, 40 Stage II, 20 Stage III, and 6 Stage IV patients. Median follow-up time was 46 months (range, 1-225 months). Of the 75 patients treated with curative intent, 29 did not receive PMRT and 46 completed PMRT. Patients who received PMRT demonstrated no benefit in overall survival (p = 0.872) but significantly better local recurrence free survival (p < 0.001) compared with those who did not receive RT. There was trend toward improving locoregional recurrence with PMRT in patients with high-risk features (node-positive, advanced stage, and {<=}2 mm or unknown surgical margin). The median, 5-year, and 10-year disease-free survival and overall survival for the 75 patients were 77.7 months, 66.3%, 32.7%, and 91.2 months, 73.9%, and 36.6%, respectively. Conclusion: The experience at LRCP suggests that high-risk MBC patients should consider PMRT to improve their chance of local recurrence-free survival.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Effect of Radiotherapy Techniques (IMRT vs. 3D-CRT) on Outcome in Patients With Intermediate-Risk Rhabdomyosarcoma Enrolled in COG D9803-A Report From the Children's Oncology Group

Purpose: To compare the dosimetric parameters of intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT) in patients with intermediate-risk rhabdomyosarcoma and to analyze their effect on locoregional control and failure-free survival (FFS). Methods and Materials: The study population consisted of 375 patients enrolled in the Children's Oncology Group protocol D9803 study, receiving IMRT or 3D-CRT. Dosimetric data were collected from 179 patients with an available composite plan. The chi-square test or Fisher's exact test was used to compare the patient characteristics and radiotherapy parameters between the two groups. The interval-to-event outcomes were estimated using the Kaplan-Meier method and compared using log-rank tests. Cox proportional hazards regression analysis was used to examine the effect of the treatment technique on FFS after adjusting for primary site and risk group. Results: The median follow-up time was 5.7 and 4.2 years for patients receiving 3D-CRT and IMRT, respectively. No differences in the 5-year failure of locoregional control (18% vs. 15%) or FFS (72% vs. 76%) rates were noted between the two groups. Multivariate analysis revealed no association between the two techniques and FFS. Patients with primary tumors in parameningeal sites were more likely to receive IMRT than 3D-CRT. IMRT became more common during the later years of the study. Patients receiving IMRT were more likely to receive >50 Gy, photon energy of {<=}6 MV, and >5 radiation fields than those who received 3D-CRT. The coverage of the IMRT planning target volume by the prescription dose was improved compared with the coverage using 3D-CRT with similar target dose heterogeneity. Conclusions: IMRT improved the target dose coverage compared with 3D-CRT, although an improvement in locoregional control or FFS could not be demonstrated in this population. Future studies comparing the integral dose to nontarget tissue and late radiation toxicity between the two groups are warranted.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Risk Factors for Regional Nodal Relapse in Breast Cancer Patients With One to Three Positive Axillary Nodes

Purpose: In many centers, supraclavicular fossa radiotherapy (SCF RT) is not routinely offered to breast cancer patients with one to three positive lymph nodes. We aimed to identify a subgroup of these patients who are at high risk of supra or infraclavicular fossa relapse (SCFR) such that they can be offered SCFRT at the time of diagnosis to improve long term locoregional control. Methods and Materials: We performed a retrospective analysis of the pathological features of 1,065 cases of invasive breast cancer with one to three positive axillary lymph nodes. Patients underwent radical breast conserving surgery or mastectomy. A total of 45% of patients received adjuvant chest wall/breast RT. No patients received adjuvant SCFRT. The primary outcome was SCFR. Secondary outcomes were chest wall/breast recurrence, distant metastasis, all death, and breast-cancer specific death. Kaplan-Meier estimates were used to calculate actuarial event rates and survival functions compared using log-rank tests. Multivariate analyses (MVA) of factors associated with outcome were conducted using Cox proportional hazards models. Results: Median follow-up was 9.7 years. SCFR rate was 9.2%. Median time from primary diagnosis to SCFR was 3.4 years (range, 0.7-14.4 years). SCFR was associated with significantly lower 10-year survival (18% vs. 65%; p < 0.001). Higher grade and number of positive lymph nodes were the most significant predictors of SCFR on MVA (p < 0.001). 10 year SCFR rates were less than 1% in all patients with Grade 1 cancers compared with 30% in those having Grade 3 cancers with three positive lymph nodes. Additional factors associated with SCFR on univariate analysis but not on MVA included larger nodal deposits (p = 0.002) and proportion of positive nodes (p = 0.003). Conclusions: Breast cancer patients with one to three positive lymph nodes have a heterogenous risk of SCFR. Patients with two to three positive axillary nodes and/or high-grade disease may warrant consideration of SCFRT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Recursive Partitioning Analysis Index Is Predictive for Overall Survival in Patients Undergoing Spine Stereotactic Body Radiation Therapy for Spinal Metastases

Purpose: To generate a prognostic index using recursive partitioning analysis (RPA) for patients undergoing spine stereotactic body radiation therapy (sSBRT) for spinal metastases (sMet). Methods and Materials: From an institutional review board-approved database, 174 patients were treated for sMet with sSBRT between February 2006 and August 2009. Median dose was 14 Gy (range, 8-24 Gy), typically in a single fraction (range, 1-5). Kaplan-Meier analysis was performed to detect any correlation between survival and histology. Histologies were divided into favorable (breast and prostate), radioresistant (renal cell, melanoma and sarcoma), and other (all other histologies). RPA was performed to identify any association of the following variables with overall survival (OS) following sSBRT: histology, gender, age, Karnofsky performance status (KPS), control of primary, extraosseous metastases, time from primary diagnosis (TPD), dose of sSBRT ({<=}14 Gy vs. >14 Gy), extent of spine disease (epidural only, bone and epidural, bone only), upfront or salvage treatment, presence of paraspinal extension, and previous surgery. Results: Median follow-up was 8.9 months. Median OS time from sSBRT was 10.7 months. Median OS intervals for favorable histologies were 14 months, 11.2 months for radioresistant histologies, and 7.3 months for other histologies (p = 0.02). RPA analysis resulted in three classes (p < 0.0001). Class 1 was defined as TPD of >30 months and KPS of >70; Class 2 was TPD of >30 months and KPS of {<=}70 or a TPD of {<=}30 months and age <70 years old; Class 3 was TPD of {<=}30 months and age {>=}70 years old. Median OS was 21.1 months for Class 1 (n = 59), 8.7 months for Class 2 (n = 104), and 2.4 months for Class 3 (n = 11). Conclusion: sSBRT patients treated for sMet have a wide variability in OS. We developed an RPA classification system that is predictive of OS. While many patients are treated for palliation of pain or to avoid symptomatic progression, this index may be used to predict which patients may benefit most from sSBRT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Long-Term Outcomes After Maximal Surgical Resection and Intraoperative Electron Radiotherapy for Locoregionally Recurrent or Locoregionally Advanced Primary Renal Cell Carcinoma

Purpose: To report outcomes of a multimodality therapy combining maximal surgical resection and intraoperative electron radiotherapy (IOERT) for patients with locoregionally (LR) recurrent renal cell carcinoma (RCC) after radical nephrectomy or LR advanced primary RCC. Methods and Materials: From 1989 through 2005, a total of 22 patients with LR recurrent (n = 19) or LR advanced primary (n = 3) RCC were treated with this multimodality approach. The median patient age was 63 years (range 46-78). Twenty-one patients (95%) received perioperative external beam radiotherapy (EBRT) with a median dose of 4,500 cGy (range, 4,140-5,500). Surgical resection was R0 (negative margins) in 5 patients (23%) and R1 (residual microscopic disease) in 17 patients (77%). The median IOERT dose delivered was 1,250 cGy (range, 1,000-2,000). Overall survival (OS) and disease-free survival (DFS) and relapse patterns were estimated using the Kaplan-Meier method. Results: The median follow-up for surviving patients was 9.9 years (range, 3.6-20 years). The OS and DFS at 1, 5, and 10 years were 91%, 40%, and 35% and 64%, 31%, and 31%, respectively. Central recurrence (within the IOERT field), LR relapse (tumor bed or regional lymph nodes), and distant metastases at 5 years were 9%, 27%, and 64%, respectively. Mortality within 30 days of surgery and IOERT was 0%. Five patients (23%) experienced acute or late National Cancer Institute Common Toxicity Criteria (NCI-CTCAE) Version 4 Grade 3 to 5 toxicities. Conclusions: In patients with LR recurrent or LR advanced primary RCC, a multimodality approach of perioperative EBRT, maximal surgical resection, and IOERT yielded encouraging results. This regimen warrants further investigation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Cervical Lymph Node Metastases From Unknown Primary Cancer: A Single-Institution Experience With Intensity-Modulated Radiotherapy

Purpose: To determine the effectiveness and rate of complications of intensity-modulated radiotherapy (IMRT) in the treatment of cervical lymph node metastases from unknown primary cancer. Methods and Materials: Between February 2005 and November 2008, 25 patients with an unknown primary cancer underwent IMRT, with a median radiation dose of 70 Gy. The bilateral neck and ipsilateral putative pharyngeal mucosa were included in the target volume. All patients had squamous cell carcinoma, except for 1 patient who had adenosquamous differentiation. They were all treated with curative intent. Of the 25 included patients, 20 were men and 5 were women, with a median age of 54 years. Of these patients, 3 had Stage III, 18 had Stage IVa, and 4 had Stage IVb. Of the 25 patients, 18 (72%) received platinum-based chemotherapy in a combined-modality setting. Neck dissection was reserved for residual disease after definitive IMRT. Overall survival, disease-free survival, and locoregional control were calculated using the Kaplan-Meier method. Results: With a median follow-up of 38 months, the overall survival, disease-free survival, and locoregional control rates were all 100% at 3 years. No occurrence of primary cancer was observed during the follow-up period. The reported rates of xerostomia reduced with the interval from the completion of treatment. Nine patients (36%) reported Grade 2 or greater xerostomia at 6 months, and only 2 (8%) of them reported the same grade of salivary function toxicity after 24 months of follow-up. Conclusion: In our institution, IMRT for unknown primary cancer has provided good overall and disease-free survival in all the patients with an acceptable rate of complications. IMRT allowed us to address the bilateral neck and ipsilateral putative pharyngeal mucosa with minimal late salivary function toxicity. The use of concurrent chemotherapy and IMRT for more advanced disease led to good clinical results with reasonable toxicities.

62 RADIOLOGY AND NUCLEAR MEDICINE↗