Preoperative functional capacity and postoperative outcomes following abdominal and pelvic cancer surgery: a systematic review and meta-analysis

Background There is clinical uncertainty regarding an association between preoperative functional capacity of cancer patients, and postoperative outcomes. The aim of this systematic review and meta-analysis is to investigate whether poor performance on preoperative six-minute walk test (6MWT) or five-times sit to stand test (5STS) is associated with worse postoperative complication rates and prolonged length of hospital stay (LOS) in cancer patients. Methods An electronic search was performed from earliest available record to 26th February 2021 in MEDLINE, Embase and AMED. Studies investigating the association between preoperative physical function (measured using either 6MWT or 5STS) and postoperative outcomes (complications and LOS) in patients with gastrointestinal, abdominal and pelvic cancers were included. Risk of bias was assessed using the Quality in Prognosis Studies (QUIPS) tool. Where possible, summary odds ratios (OR) or mean differences (MD), and 95% confidence intervals (CI) were calculated using random-effect models. Results Five studies (379 patients) were included, of which none utilized the 5STS. Overall, studies were rated as having low to moderate risk of bias. Higher preoperative performance on the 6MWT (>= 400 m) was associated with low grade postoperative complications (OR = 0.38; 95% CI = 0.15-0.95) but was not associated with a shorter LOS (MD = 3.29; 95%CI = -1.07-7.66). Conclusion The available evidence suggests that in cancer patients, a higher preoperative functional capacity may be associated with reduced postoperative complications. Conversely, there is no significant association between preoperative function and LOS. Further high-quality studies are needed in this area, including studies involving 5STS.