Surgical Management of Metachronous Liver Metastasis after Watch-and-Wait Strategy in Rectal Cancer Patients with Complete Response: A Case Report.

Abstract

The watch-and-wait (W&W) strategy has become an accepted organ-preserving approach for rectal cancer patients who achieve a clinical complete response (cCR) after total neoadjuvant therapy (tNt). however, the occurrence of metachronous colorectal liver metastases (CRLM) in this setting presents important therapeutic challenges. Evidence regarding the optimal surgical strategy-particularly the role of laparoscopic anatomical resection in centrally located liver segments-remains limited. We report the case of a 54-year-old male with ct3N0M0 rectal adenocarcinoma who achieved cCR following tNt and was subsequently managed with a W&W strategy. During routine surveillance, a soli- tary metachronous liver metastasis (15 mm) was detected in segment 4b. After a multidisciplinary tumor board review, the patient underwent laparoscopic anatomical segment 4b resection using an intrahepatic Glissonean approach. The postoperative course was uneventful, and the patient was discharged on postoperative day 6. histopathological exami- nation confirmed metastatic moderately differentiated adenocarcinoma with a microsatellite stable (MSS) phenotype and KRAS/BRAF wild-type status. This case demonstrates that laparoscopic anatomical segment 4b resection is a safe and feasible option for carefully selected patients with metachronous CRLM managed within a W&W strategy. The minimally invasive anatomical approach allowed precise vascular control and achievement of oncologically adequate margins in a technically demanding central segment. Larger clinical series are needed to define optimal management strategies and long-term oncologic outcomes in this setting.