Adjuvant radiotherapy for stage I endometrial cancer

Background The role of adjuvant radiotherapy (both pelvic external beam radiotherapy and vaginal intracavity brachytherapy) in stage I endometrialcancer following total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH and BSO) remains unclear. Objectives To assess the efficacy of adjuvant radiotherapy following surgery for stage I endometrial cancer. Search methods The Cochrane Central Register of Controlled Trials (CENTRAL) Issue 2, 2006, MEDLINE, EMBASE, CancerLit, Physician Data Query (PDQ) ofNational Cancer Institute. Handsearching was also carried out where appropriate. Selection criteria Randomised controlled trials (RCTs) which compared adjuvant radiotherapy versus no radiotherapy following surgery for patients withstage I endometrial cancer were included. Data collection and analysis Quality of the studies was assessed and data collected using a predefined data collection form. The primary endpoint was overall survival.Secondary endpoints were locoregional recurrence, distant recurrence and endometrial cancer death. Data on quality of life (QOL) andmorbidity were also collected. A meta-analysis on included trials was performed using the Cochrane Collaboration Review ManagerSoGware 4.2. Main results The meta-analysis was performed on four trials (1770 patients). The addition of pelvic external beam radiotherapy to surgery reducedlocoregional recurrence, a relative risk (RR) of 0.28 (95% confidence interval (CI) 0.17 to 0.44, p < 0.00001), which is a 72% reduction in therisk of pelvic relapse (95% CI 56% to 83%) and an absolute risk reduction of 6% (95% CI of 4 to 8%). The number needed to treat (NNT)to prevent one locoregional recurrence is 16.7 patients (95% CI 12.5 to 25). The reduction in the risk of locoregional recurrence did nottranslate into either a reduction in the risk of distant recurrence or death from all causes or endometrial cancer death. A subgroup analysisof women with multiple high risk factors (including stage 1c and grade 3) showed a trend toward the reduction in the risk of death from allcauses and endometrial cancer death in patients who underwent adjuvant external beam radiotherapy.