Ericka Wiebe

Consensus recommendations for radiation therapy contouring and treatment of vulvar carcinoma

PURPOSE The purpose of this study was to develop a radiation therapy (RT) contouring atlas and recommendations for women with postoperative and locally advanced vulvar carcinoma. METHODS AND MATERIALS An international committee of 35 expert gynecologic radiation oncologists completed a survey of the treatment of vulvar carcinoma. An initial set of recommendations for contouring was discussed and generated by consensus. Two cases, 1 locally advanced and 1 postoperative, were contoured by 14 physicians. Contours were compared and analyzed using an expectation-maximization algorithm for simultaneous truth and performance level estimation (STAPLE), and a 95% confidence interval contour was developed. The level of agreement among contours was assessed using a kappa statistic. STAPLE contours underwent full committee editing to generate the final atlas consensus contours. RESULTS Analysis of the 14 contours showed substantial agreement, with kappa statistics of 0.69 and 0.64 for cases 1 and 2, respectively. There was high specificity for both cases (≥99%) and only moderate sensitivity of 71.3% and 64.9% for cases 1 and 2, respectively. Expert review and discussion generated consensus recommendations for contouring target volumes and treatment for postoperative and locally advanced vulvar cancer. CONCLUSIONS These consensus recommendations for contouring and treatment of vulvar cancer identified areas of complexity and controversy. Given the lack of clinical research evidence in vulvar cancer radiation therapy, the committee advocates a conservative and consistent approach using standardized recommendations.

Palliative whole brain radiotherapy: Predictors of prescribing 5 versus 10 fractions.

219 Background: The optimal dose for palliative whole brain radiotherapy (WBRT) continues to be debated. Common regimens include 20 Gy in five and 30 Gy in 10 fractions. We aimed to identify factors associated with WBRT dose schedules, hypothesizing that clinical prediction of survival (CPS) would influence prescribing practice. METHODS Demographic and clinicopathologic data were collected for consecutive patients with brain metastases receiving WBRT through a dedicated palliative radiation oncology clinic. At initial consultation, CPS were prospectively collected from treating radiation oncologists. Karnofsky performance status (KPS) and Mini-Mental Status Examination were available for 88.6% and 75.1%, respectively. Dose fractionation was collected and summary statistics calculated. Parameters were assessed for association with five fraction schedules using binary logistic regression, with odds ratios and 95% CI reported. RESULTS 193 patients underwent WBRT (N = 102 from 2010-2012; N = 91 from 2013-2014); 38/193 had 48 extracranial sites irradiated concurrently. 46.1% were male, mean age was 64.7 years (SD 11.6), and 63.7% had lung cancer. Median KPS was 70 (range 20-100) and median MMSE score was 27/30 (range 13-30). Median CPS and actual survival were 150 days (range 21-730d) and 96 days (range 11-1029d), respectively. 18.7% received WBRT within 30 days of death. 78.2% (151/193) and 17.6% (34/193) received five and 10 fractions, respectively; 8/193 were prescribed other schedules. On multivariate analysis, patients with KPS ≤ 70 were 5.93 times more likely to have received 5-fractions (95% CI 2.51-14.1; p < 0.0001). Those treated 2010-2012 were less likely to have received 5 fractions (OR 0.28; 95% CI 0.11-0.68; p = 0.005). CPS, age, gender, MMSE, histology, disease extent, and extracranial irradiation were not predictive of WBRT schedule. CONCLUSIONS Patients treated with WBRT with KPS ≤70 and those treated more recently were more likely to receive five fractions. Oncologist CPS was not a statistically significant predictor of schedule in this cohort.

Does expected survival influence palliative radiotherapy treatment recommendations

35 Background: Survival is often overestimated, yet physicians rely on such predictions to recommend appropriate therapy and assist with end-of-life planning. Administration of radiotherapy (RT) within the last 30 days of life has been suggested as an indicator of poor quality care, since acute side effects reduce quality of life with insufficient time for symptomatic benefit. We investigated whether life expectancy predicted at the time of consultation correlates with palliative RT recommendations. METHODS Radiation oncologists from a dedicated palliative Radiation Oncology outpatient clinic anonymously completed survival estimations after clinical assessment, and recorded factors upon which each estimate was based. Demographics, primary histology, RT details, and date of death were abstracted. Summary statistics and Kaplan-Meier estimates of actual survival (AS) were obtained. Correlations between AS and clinical predictions of survival (CPS) were calculated using Spearmans correlation coefficient (r). Multivariate logistic regression analysis explored factors associated with RT recommendations. RESULTS 476 survival predictions were made for 420 unique patients (06/2010-01/2014). Median age was 67.7 years, 61.9% were male and 44.0% had lung cancer. Karnofsky Performance Status (KPS) was > 70 at 23.9% of clinic visits. At 84.5% of consultations, RT was prescribed to 538 separate volumes (29.2% receiving 8Gy, 54.8% 20Gy, 6.3% 30Gy, 9.7% other). Mean AS was 179 days (SD 187d), moderately correlating with mean CPS of 242 days (SD 261d) with r = 0.38 (p < 0.0001). Factors most frequently cited as influencing CPS were KPS and extent of disease. At the time of 30/476 visits, CPS was < 30 days; at 19 of these visits, RT was prescribed to 26 volumes (21 bone, 3 whole brain, 2 chest), 2/3 as single fractions, finishing a median of 17 days before death. Expected survival was predictive of prescribed RT dose on univariate logistic regression, but did not retain significance on multivariate analysis. CONCLUSIONS Despite international surveys in which prognosis has been cited as the main factor affecting treatment decisions, in this cohort, other aspects appear to have more strongly influenced palliative RT recommendations.

Controversies in the Management of Advanced Vulvar Cancer

Optimal management of advanced vulvar cancer remains one of the most controversial issues within the treatment of gynecologic malignancies. Multimodality therapy that integrates (chemo)radiotherapy with less extensive surgery is well accepted in order to avoid stoma formation; however, the roles for adjuvant therapy after surgical management of both the primary and nodal disease are poorly defined. To avoid exenterative surgery in advanced disease, controversial alternatives including definitive (chemo)radiotherapy and neo-adjuvant chemotherapy have been explored, but are not clearly established. Unfortunately many of these controversies cannot be resolved definitively due to a lack of Level 1 and 2 evidence. Small retrospective series and expert multidisciplinary opinion can guide management in order to obtain the therapeutic advantages of the modalities available and must be tailored to the patient- and tumor-related factors in each situation.