[The Watch and Wait Strategy for Lower Rectal Cancer Patients Who Achieved Clinical Complete Response after Chemotherapy to Treat Inguinal Lymph Node Metastasis following Total Neoadjuvant Therapy-A Case Report].

The watch and wait strategy(W&W)is optional non-operative management for lower advanced rectal cancer patients who have achieved clinical complete response(cCR)following neoadjuvant treatment. However, the clinical implication of surgical intervention for the primary lesion is not well elucidated when distant metastasis appears with complete remission of the primary lesion. We report a case of a 47-year-old-woman with lower rectal cancer presenting inguinal lymph node metastasis after total neoadjuvant therapy(TNT)and managed through W&W after achieving cCR following chemotherapy. TNT was performed as a preoperative treatment for lower advanced rectal cancer, cT3N2aM0, cStage Ⅲb. Although the primary lesion and mesenteric lymph node metastasis completely disappeared, bilateral inguinal lymph node metastasis appeared immediately after TNT. The patient was treated with FOLFOX plus panitumumab for rectal cancer with RAS and BRAF wild-type. Four months after chemotherapy, the inguinal lymph node metastasis disappeared, and W&W was used for the management. She stayed alive without recurrence 1 year and 9 months after chemotherapy.