Postoperative Complications and Risk Factors in Skin Tumor Excision With Simple Suturing Under Local Anesthesia: A Multicenter Retrospective Study in Japan.

Skin tumor excision under local anesthesia with simple suturing is widely performed in outpatient dermatological practice. Although generally considered safe, postoperative complications such as wound dehiscence, infection, and contact dermatitis can negatively impact patients' quality of life and healthcare resources. However, limited data are available on the complication rates and associated risk factors in procedures without reconstructive techniques. We retrospectively analyzed 1291 patients who underwent local excision and simple closure of skin tumors at three institutions in Japan between January 2021 and November 2024. Complications were defined as adverse events requiring medical intervention within 30 days postoperatively. Receiver operating characteristic curves were used to determine the cutoff values for age, tumor size, operative time, and surgeon experience. Logistic regression analysis was performed to identify independent risk factors. A total of 168 complications occurred in 164 patients (12.7%). The most common symptoms were contact dermatitis (3.7%), wound dehiscence (3.3%), and surgical site infection (2.9%). Multivariate analysis revealed tumor size ≥ 10 mm (odds ratio [OR] 1.52, p = 0.040), operative time ≥ 38 min (OR 1.84, p = 0.012), and surgeon experience ≥ 10 years (OR 1.64, p = 0.013) as significant risk factors. In contrast, intraoperative antibiotic use significantly reduced complication risks (OR 0.29, p < 0.001), especially the risk of surgical site infections (OR 0.32, p = 0.024). No serious or life-threatening events occurred. This study identified key predictors of postoperative complications in skin tumor surgery performed under local anesthesia. Larger tumors, longer operative times, and more experienced surgeons were associated with a higher risk, possibly because of the procedural complexity. Prophylactic intraoperative antibiotics effectively reduce infections and should be considered in high-risk cases. These findings support evidence-based risk assessment and perioperative management of dermatological surgery.