Extreme surgery using the hypothermic perfusion technique for conventionally unresectable abdominal malignant tumours: A systematic review and meta-analysis.

Background: Extreme surgery using the hypothermic perfusion technique is often the only treatment option to achieve R0 resection and long-term prognosis for abdominal tumours that are either conventionally unresectable or contraindicated to allotransplantation. We conducted a systematic review and meta-analysis to delineate the indications and outcomes of extreme surgery.

Materials And Methods: Human studies on extreme resection for abdominal malignant tumours were searched among five databases between January 1988 to March 2023. The Risk Of Bias In Non-randomised Studies - of Interventions tool was used to assess the risk of bias. A meta-analysis of proportions was performed, pooling 1-, 3- and 5-year overall survival and recurrence rates.

Results: This study comprised 73 studies encompassing 333 patients who underwent extreme liver resection (in situ, n = 127; ante situm, n = 72; ex situ, n = 134). Additionally, 90 patients from 17 studies focusing on extreme resection of other (non-hepatic) organs were included. The pooled 90-day mortality and 1- and 5-year overall survival rates were 7.3 %, 72.3 % and 23.4 %, respectively. The 1- and 5-year recurrence rates were 38.7 % and 86.1 %, respectively. Patients aged <65 years had a significantly lower 90-day mortality (5.5 % vs. 29.6 %; P = 0.022) and a higher 5-year overall survival rate (23.9 % vs. 0 %; P < 0.001) than those aged ≥65 years. Additionally, non-epithelial tumours were associated with favourable prognosis compared with epithelial tumours.

Conclusion: Extreme surgery offers acceptable outcomes for younger patients with non-epithelial tumours that are either unresectable by conventional cancer surgery or contraindicated to allotransplantation.