ESTRO 2020 Abstract book

S649 ESTRO 2020

that has a positive effect on the utilization of lymphadenectomy included: younger age, earlier year of diagnosis, private insurance, residing in well-educated and higher-income areas, smaller tumor size, and negative tumor margins. The only factor significant for lymphadenectomy on multivariable analysis was younger age (p<0.001). Predictors of overall survival on univariable analysis included: younger age, private insurance, better performance status, negative margins, node negativity, radiation therapy and lymphadenectomy. On multivariable analysis, the only factors influencing survival were: age (HR 1.015/year [95%CI 1.004-1.026], p=0.006), positive margins (HR 1.313 [95%CI 1.012-1.702], p=0.040), and lymphadenectomy (HR 0.763 [95%CI 0.588-0.989], p=0.041). Conclusion These data suggest that systematic lymphadenectomy improves survival in women with vaginal melanoma. These findings should be confirmed with institutional-level data. PO-1143 Temporal course of late toxicity in patients undergoing pelvic radiation for cervical cancer J. Shejul 1 , S. Chopra 1 , N. Ranjan 1 , P. Patil 2 , L. Naidu 1 , S. Mehta 2 , U. Mahantshetty 1 1 Tata Memorial Center, Radiation Oncology, Mumbai, India ; 2 Tata Memorial Center, Medical Gastroenterology, Mumbai, India Purpose or Objective Chemo-radiation (CRT) and brachytherapy (BT) for cervix cancer is associated with small percentage of moderate to severe late toxicities. While crude incidence of late events is often reported, there is a limited information on the temporal course. The present study reports on the temporal course of late toxicities, response to therapeutic interventions and direct costs. Material and Methods Women with cervical cancer who underwent CRT and BT and developed late rectal and bladder toxicities between Jan 2014 to June 2017 were included. Grade of toxicity (CTCAE version 4.03) and type of intervention performed was recorded at every 3-month interval. Proportion of patients with grade I-IV toxicity at presentation, 12 and 24 months and change in severity over a period of time was calculated. Number of clinical interventions, need for inpatient admissions, response to intervention and direct cost of intervention was calculated using hospital procedure billing codes. Results Ninety-two patients were identified with late radiation toxicity. With a median follow up of 31 months (10- 144) the median time to develop toxicity was 12 (3 to 111) months. Grade I, II, III, IV toxicity was observed in 54%, 36%, 8% and 2% patients at first reporting. On an average, patient spent 12 (3-27) months with symptoms of toxicity. At 12 months 48/92 (52.2%) had complete resolution of toxicity however, 27/92 (29.3%) patients continued to have low grade (I-II) persistent toxicity. Only 6 patients (6.5%) who had grade III-IV toxicity had resolution to a lower grade whereas seven (7.6%) had persistent grade ≥ III toxicity despite interventions. Four patients (4.3%) died due to toxicity. At 24 months, 10% patients continued to have grade ≥ III toxicity. A median of 7 (2-24) interventions were required for clinical management. Apart from dietary modifications and medical treatment, blood transfusions were needed in 43% patients. Up to 60% patients also required argon plasma coagulation (average 2 sessions). Inpatient admission was needed for 60% patients for a median of 7 days (7-56 days). Hyperbaric oxygen therapy (HBOT) (25- 40 sessions) was needed for 21.7% of patients and was associated with 90% symptom resolution Average cost of toxicity management was 800 (10-4700) Euros which is

Conclusion Gynaecological cancer patients who present with brain metastases without extracranial disease and good performance status show a favourable prognosis. This information is important for the physician both in treatment decision and when giving information to the patient about their prognosis. A proportion of these patients should probably receive best supportive care and no radiotherapy for their brain metastases. For the majority of patients with gynaecological cancers and BM the prognosis remains poor. PO-1142 Lymphadenectomy for vaginal melanoma, does it improve outcomes? Z. Horne 1 , S. Teterichko 2 , R. Wegner 1 , S. Hasan 3 , S. Crafton 4 , E. Miller 4 , T. Krivak 4 , P. Sukumvanich 2 , S. Beriwal 5 1 Allegheny Health Network Cancer Institute, Radiation Oncology, Pittsburgh, USA ; 2 University of Pittsburgh Medical Center, Gynecologic Oncology, Pittsburgh, USA ; 3 New York Proton Center, Radiation Oncology, New York, USA ; 4 Allegheny Health Network Cancer Institute, Gynecologic Oncology, Pittsburgh, USA ; 5 University of Pittsburgh Medical Center, Radiation Oncology, Pittsburgh, USA Purpose or Objective Vaginal melanomas are rare with case reports/series to guide treatment protocols. Most treatment is guided by mucosal melanomas of the head and neck. Systematic lymphadenectomy has been suggested to be of benefit in vulvar melanomas but its value is unclear in vaginal melanomas. Material and Methods The National Cancer Database was queried for women diagnosed with non-metastatic melanoma of the vagina from 2004-2016. Factors which influenced survival were queried with Kaplan-Meier and log-rank test and multivariable analysis conducted via Cox proportional hazards. Factors which influenced the utilization of lymphadenectomy were explored with bivariate regression analysis. Significance was set at p<0.05. Results Six hundred and eighteen cases were identified. Lymphadenectomy was utilized in 195 (31.6%) of patients with the peak utilization occurring in 2008 with 47.5% of cases including lymphadenectomy and minimal utilization occurring in 2015 with only 12.5% of cases including lymphadenectomy. Of the 195 women undergoing lymphadenectomy, 56 (28.7%) had positive lymph nodes. Median follow up was 19.2 months. Median survival of women with negative nodes was 28.6 months, 17.9 months if nodes were positive and 18.9 months if lymphadenectomy was not performed (p<0.001). Factors