Prognostic factors in patients receiving palliative radiotherapy for female genital tract cancer

Abstract

Purpose or Objective The 5 year survival of female genital tract cancer (FGTC) is approximately 15%. In the management of advanced female genital tract cancer (FGTC), palliative radiotherapy plays an important role. There is little data reporting the outcome of palliative radiotherapy in this setting and the quality of evidence available for prognostic indicators to inform patient selection is suboptimal. Materials and Methods Data of patients receiving palliative radiotherapy for FGTC was collected retrospectively including patient demographics, disease and treatment characteristics from two UK cancer centres. Overall survival was calculated from the date of completion of radiotherapy using the Kaplan Meier method. Descriptive statistics were used for quantitative variables. The association between the patient, disease and, treatment factors and the survival after completion of radiotherapy was analysed using ANOVA with a significance threshold of p=0.05. Results A total of 184 patients were included in the study. Table-1 shows baseline patient demographics. Of all patients, 35.3% received prior radical treatment for FGTC and then subsequently relapsed. The radiotherapy schedules used varied significantly and ranged from 10Gy/1# to more protracted regimens like 50Gy/20# but the most commonly used regimen was 35Gy/15#(33.6%). The prescribed regimens were well tolerated with only 1.7% unable to complete the planned course of palliative radiotherapy. Most patients (40.7%) did not experience acute toxicity related to palliative radiotherapy, however, grade 3 acute toxicity was noted in 8.1% of the patients. After completion of palliative radiotherapy, 70.6% had a subjective response and 34.2% went on to have further cancer-directed treatment. The median survival after radiotherapy is 6 months and ranged from 1 month to 6 years. Upon analysis of the prognostic factors, the absence of distant metastases (p=0.019) and receipt of further lines of treatment (p=0.045) were found to have a positive influence on the survival after radiotherapy. Qualitative variables like performance status, comorbidities (ACE 27) and quantitative variables like EQD2 of the radiotherapy schedule, number of metastases or visceral metastases did not significantly associate with survival post palliative radiotherapy. Conclusion Palliative radiotherapy to the pelvis in advanced FGTC is well tolerated with a majority having a subjective response. Patients with distant metastases who could not receive further lines of oncologic treatment fared significantly poorly. With limited life expectancy in these patients, choice of radiotherapy schedule is key when balancing symptoms and pelvic disease control.