Faculty Bibliography

BACKGROUND:There has been an increase in the utilization of single-fraction stereotactic body radiation therapy (SBRT) to treat thoracic structures, but there have been few reports describing toxicity outcomes with this treatment. METHODS:We evaluated 119 sites (114 patients) with no prior history of thoracic radiation were treated from 10/1/2003 to 10/27/2008 with single-fraction SBRT to thoracic structures. The median dose to the gross tumor volume was 2400 cGy (range 1800-2400 cGy), as was the median dose to the planning target volume (range 1600-2400 cGy). A detailed review of thoracic toxicities was performed to include pneumonitis or Grade 2 or higher esophageal and bronchial toxicity. In addition, we retrospectively contoured the esophagus and bronchus of 48 patients treated in 2004-2005, prior to the establishment of dose constraints to determine the range of doses that these structures received. RESULTS:Of the contoured patients, the median dose to the hottest 1cc (D1cc) of the esophagus was 1250 cGy (range 158-2572 cGy). The median bronchial D1cc was 1101 cGy (range 260-2211 cGy). At a median follow-up of 11.6 months, there were seven Grade 2 or higher esophageal toxicities, including one Grade 3 and one Grade 4 toxicities. There were two bronchial toxicities, one Grade 2 and one Grade 3. There were no cases of pneumonitis. CONCLUSIONS:High-dose single-fraction SBRT is well tolerated to the thoracic region, with most patients tolerating high doses to central structures without significant toxicity.

Strategic planning for the Radiation Therapy Committee of the Southwest Oncology Group (SWOG) is comprehensively evaluated every six years in an effort to maintain a current and relevant scientific focus, and to provide a standard platform for future development of protocol concepts. Participants in the 2008 Strategic Planning Workshop included clinical trial experts from multiple specialties, industry representatives from both pharmaceuticals and equipment manufacturers, and basic scientists. High-priority research areas such as image-guided radiation therapy for control of limited metastatic disease, analysis of biomarkers for treatment response and late toxicity, assessment of novel agents in combination with radiation, standardization of radiation target delineation, and the assessment of new imaging techniques to individualize cancer therapy, were discussed. Research priorities included clinical study designs featuring translational end points that identify patients most likely to benefit from combined modality therapy; intervention including combination radiation with standard chemotherapy; radiation with radiosensitizing molecular-targeted therapies; and stereotactic radiation for treatment of patients with regard to asymptomatic metastasis and radiation-induced tumor autoimmunity. The Committee concluded that the future research opportunities are among the most exciting to have developed in the last decade, and work is in progress to embark on these plans.

For men diagnosed with clinically localized prostate cancer, definitive therapy with radical prostatectomy, external beam radiation therapy, or brachytherapy offers a high chance of cure. Currently, there are insufficient data to recommend 1 treatment approach over another, leaving physicians and patients to decide based on their own biases and preferences. Prediction tools, such as nomograms and probability tables, have been created as decision aids to facilitate patient counseling and decision making. Nomograms in particular can assess the therapeutic efficacy of a given therapy by providing individualized estimates of the risk of failure after treatment. The authors performed a comprehensive literature review to identify nomograms assessing the efficacy of brachytherapy in patients with clinically localized prostate cancer, and found a paucity of such models. Analysis of currently available brachytherapy nomograms reveals suboptimal predictive power compared with models based on other treatment modalities. The purpose of this review is to spur development of new and more accurate prediction tools for predicting outcomes after brachytherapy, offering physicians and patients the opportunity to equally assess the efficacy of all available treatment modalities for clinically localized prostate cancer. Cancer 2009;115(13 suppl):3121-7. (c) 2009 American Cancer Society.

PURPOSE/OBJECTIVE:Quality Research in Radiation Oncology (QRRO) has embarked on a new national process survey to provide benchmark data that will allow radiation oncologists to assess the quality of care in their own practices by measuring quality indicators (QIs) and comparing individual with national practice. METHODS:Investigators at QRRO developed QIs on the basis of nationally recognized, evidence-based guidelines such as those of the National Comprehensive Cancer Network, as well as additional emerging QIs for processes involving rapidly emerging technology. They specifically defined the QIs as clinical performance measures. Published results of the national survey database for patients treated in 1998 and 1999 were reviewed and additional analyses conducted to assess data adequacy to measure compliance with these clinical performance measures. RESULTS:Examples of workup QIs for breast cancer patients showed that 97% underwent diagnostic bilateral mammography, 96% underwent pathology reviews, 83% underwent the determination of estrogen receptor status, 81% underwent the determination of progesterone receptor status, and 31% underwent the determination of human epidermal growth factor receptor 2 status. Compliance with treatment QIs for field recommendations on the basis of nodal findings can be measured. Of patients with prostate cancer, 90% underwent digital rectal examinations, 99% underwent prostate-specific antigen tests, and 99% had their Gleason scores determined. Compliance with QIs on the basis of prognostic group can also be measured. CONCLUSIONS:Benchmarking utilization patterns provides a foundation for assessing the appropriateness of cancer care in the future. The QRRO database is a rich data source, and the new survey will provide contemporary benchmark data for these measures.

BACKGROUND:To the authors' knowledge, the indications for adjuvant treatment in acinic cell carcinoma (AciCC) of the parotid gland have not been elucidated to date. The aim of the current study was to determine patterns of failure and adverse prognostic features. METHODS:Between March of 1989 and August of 2006, 35 patients underwent surgery at Memorial Sloan-Kettering Cancer Center for AciCC of the parotid gland and had their clinical and pathologic features retrospectively analyzed at the primary site. All cases were reviewed by 2 head and neck pathologists. Five-year estimates of survival outcomes were performed, followed by univariate analysis of potential prognostic features. RESULTS:The T classifications were as follows: T1 in 46% of patients, T2 in 23% of patients, T3 in 18% of patients, and T4 in 9% of patients. Three patients had cervical lymph node involvement. All patients underwent surgery as their primary treatment. Approximately 63% of patients (n = 22) received radiation treatment. The median follow-up time for surviving patients was 59.9 months. Five-year estimates of disease-free survival (DFS), overall survival (OS), and local control were 85%, 90%, and 90%, respectively. Of the clinical variables tested, clinical extracapsular extension (ECE), facial nerve sacrifice, and lymph node involvement were found to be significantly associated with a detriment in DFS and OS (P < .05). Positive surgical margins, histologic ECE, >2 mitoses per 10 high-power fields (HPF), atypical mitosis, vascular invasion, perineural invasion, pleomorphism, and necrosis were associated with adverse DFS (P < .05). All of these variables except for vascular invasion (P = .377) and perineural invasion (P = .07) were associated with OS. If high-grade tumors were defined on the basis of high mitotic activity (>2 mitoses/10 HPF) and/or tumor necrosis, high-grade carcinomas had a significantly lower DFS and OS (P = .001). CONCLUSIONS:AciCC had a low treatment failure rate, and a large number of patients could be considered candidates for surgery only. A histologic grading system was devised to help stratify patients for adjuvant treatment.

PURPOSE/OBJECTIVE:To quantify, as a function of average magnetic resonance spectroscopy (MRS) score and tumor volume, the probability that a cancer-suspected lesion has an elevated Gleason grade. METHODS AND MATERIALS/METHODS:The data consist of MRS imaging ratios R stratified by patient, lesion (contiguous abnormal voxels), voxels, biopsy and pathologic Gleason grade, and lesion volume. The data were analyzed using a logistic model. RESULTS:For both low and high Gleason score biopsy lesions, the probability of pathologic Gleason score >/=4+3 increases with lesion volume. At low values of R a lesion volume of at least 15-20 voxels is needed to reach a probability of success of 80%; the biopsy result helps reduce the prediction uncertainty. At larger MRS ratios (R > 6) the biopsy result becomes essentially uninformative once the lesion volume is >12 voxels. With the exception of low values of R, for lesions with low Gleason score at biopsy, the MRS ratios serve primarily as a selection tool for assessing lesion volumes. CONCLUSIONS:In patients with biopsy Gleason score >/=4+3, high MRS imaging tumor volume and (creatine + choline)/citrate ratio may justify the initiation of voxel-specific dose escalation. This is an example of biologically motivated focal treatment for which intensity-modulated radiotherapy and especially brachytherapy are ideally suited.

PURPOSE/OBJECTIVE:External beam radiotherapy (EBRT) plays a controversial role in the management of nonanaplastic thyroid cancer. We reviewed our institution's outcomes in patients treated with EBRT for advanced or recurrent nonanaplastic thyroid cancer. METHODS AND MATERIALS/METHODS:Between April 1989 and April 2006, 76 patients with nonanaplastic thyroid cancer were treated with EBRT. The median follow-up for the surviving patients was 35.3 months (range, 4.2-178.4). The lesions were primarily advanced and included Stage T2 in 5 (7%), T3 in 5 (7%), and T4 in 64 (84%) patients. Stage N1 disease was present in 60 patients (79%). Distant metastases before EBRT were identified in 27 patients (36%). The median total EBRT dose delivered was 6,300 cGy. The histologic features examined included medullary in 12 patients (16%) and nonmedullary in 64 (84%). Of the 76 patients, 71 (93%) had undergone surgery before RT, and radioactive iodine treatment was used in 56 patients (74%). RESULTS:The 2- and 4-year overall locoregional control rate for all histologic types was 86% and 72%, respectively, and the 2- and 4-year overall survival rate for all patients was 74% and 55%, respectively. No significant differences were found in locoregional control, overall survival, or distant metastases-free survival for patients with complete resection, microscopic residual disease, or gross residual disease. Grade 3 acute mucositis and dysphagia occurred in 14 (18%) and 24 (32%) patients, respectively. Late adverse toxicity was notable for percutaneous endoscopic gastrostomy tube use in 4 patients (5%). CONCLUSION/CONCLUSIONS:The results of our study have shown that EBRT is effective for locoregional control of selected locally advanced or recurrent nonanaplastic thyroid malignancies, with acceptable acute toxicity.

PURPOSE/OBJECTIVE:To investigate the biochemical control rates and survival for Gleason score 7-10 prostate cancer patients undergoing permanent prostate brachytherapy as a function of the biologic effective dose (BED). METHODS AND MATERIALS/METHODS:Six centers provided data on 5,889 permanent prostate brachytherapy patients, of whom 1,078 had Gleason score 7 (n = 845) or Gleason score 8-10 (n = 233) prostate cancer and postimplant dosimetry results available. The median prostate-specific antigen level was 7.5 ng/mL (range, 0.4-300). The median follow-up for censored patients was 46 months (range, 5-130). Short-term hormonal therapy (median duration, 3.9 months) was used in 666 patients (61.8%) and supplemental external beam radiotherapy (EBRT) in 620 (57.5%). The patients were stratified into three BED groups: <200 Gy (n = 645), 200-220 Gy (n = 199), and >220 Gy (n = 234). Biochemical freedom from failure (bFFF) was determined using the Phoenix definition. RESULTS:The 5-year bFFF rate was 80%. The bFFF rate stratified by the three BED groups was 76.4%, 83.5%, and 88.3% (p < 0.001), respectively. Cox regression analysis revealed Gleason score, prostate-specific antigen level, use of hormonal therapy, EBRT, and BED were associated with bFFF (p < 0.001). Freedom from metastasis improved from 92% to 99% with the greatest doses. The overall survival rate at 5 years for the three BED groups for Gleason score 8-10 cancer was 86.6%, 89.4%, and 94.6%, respectively (p = 0.048). CONCLUSION/CONCLUSIONS:These data suggest that permanent prostate brachytherapy combined with EBRT and hormonal therapy yields excellent bFFF and survival results in Gleason score 7-10 patients when the delivered BEDs are >220 Gy. These doses can be achieved by a combination of 45-Gy EBRT with a minimal dose received by 90% of the target volume of 120 Gy of (103)Pd or 130 Gy of (125)I.