Postoperative Drainage Output as an Early Postoperative Marker Associated with Unplanned Revision After Soft Tissue Sarcoma Resection

Background: Wound complications and unplanned revision surgery remain common after soft tissue sarcoma (STS) resection. Established risk models focus on patient- and tumour-related factors, while the role of operative and perioperative variables is less well defined. Methods: This retrospective single-centre study included 95 patients undergoing STS resection between 2021 and 2025. Associations with unplanned revision surgery were evaluated using univariate and exploratory multivariable logistic regression analyses. Receiver operating characteristic (ROC) analysis assessed the discriminatory performance of postoperative drainage output. Results: Unplanned revision surgery occurred in 23 patients (24%). On univariate analysis, several intraoperative and postoperative variables were associated with revision, whereas most patient- and tumour-related factors were not statistically significant. In multivariable analysis, intraoperative crystalloid administration was the only intraoperative factor associated with unplanned revision (OR 1.45 per 500 mL, 95% CI 1.05–2.02; p = 0.026). Among postoperative parameters, drainage output remained associated with revision (OR 1.45 per 100 mL, 95% CI 1.15–1.82; p = 0.005). In patients without planned secondary reconstruction, drainage output showed good exploratory discriminatory performance (AUC 0.927), with a cutoff of 925 mL providing high specificity (94.4%) with acceptable sensitivity (75%). Conclusions: In this cohort, unplanned revision was more frequently associated with markers of surgical complexity, including higher intraoperative crystalloid administration, and the early postoperative course, particularly drainage output. Drainage output appears to reflect an evolving complication rather than an independent predictor and may serve as an early clinical warning signal. Findings are hypothesis-generated and require external validation.