P12: PREDICTORS OF CONVERSION FROM MINIMALLY INVASIVE TO OPEN ADRENALECTOMY: A SYSTEMATIC REVIEW & META-ANALYSIS OF OBSERVATIONAL STUDIES

Abstract

Introduction Minimally invasive adrenalectomy has become the standard of care internationally in benign adrenal disease. Intra-operative conversion to open surgery is associated with significantly increased morbidity and prolonged hospital stay. The aim of this systematic review is to identify risk factors associated with intra-operative conversion of minimally invasive adrenalectomy. Method This systematic review was conducted according to MOOSE guidelines. PubMed, EMBASE and Cochrane library were systematically searched for observational studies evaluating risk factors for intra-operative conversion of minimally invasive adrenalectomy to open surgery. Specific risk factors of interest included patient demographics, patient co-morbidities, tumour characteristics and histology. Result Eight studies met the inclusion criteria for analysis with a total of 2939 patients. 6.02% (n=177) required intra-operative conversion. 67.5% (n=1983) underwent laparoscopic transperitoneal adrenalectomy. There were no significant associations between any patient demographics or co-morbidities and intra-operative conversion. Tumour characteristics such as right sided tumours (pooled odds ratio (OR), 1.51; 95% Confidence Interval (CI), 0.98-2.32; p=0.06) and increasing tumour size (OR, 2.29; 95% CI, 1.4-3.74; p=0.001) were shown to be significantly associated with an increased risk of conversion. Pheochromocytoma (OR, 2.21; 95% CI, 1.89-2.58; p<0.0001) and malignancy (OR, 5.38; 95% CI, 2.1-13.81; p=0.005) were also significant predictors of intra-operative conversion. Conclusion Minimally invasive adrenalectomy has significantly reduced post-operative morbidity in patients requiring adrenal surgery but the need for intra-operative conversion remains significant. Identifying patients at increased risk of conversion pre-operatively may assist intra-operative decision making and contribute to improved patient outcomes. Take-home message Minimally invasive adrenalectomy carries a significant risk of conversion. Recognising patients with known risk factors for conversion aids risk stratification and may contribute to better outcomes.