Lymph node metastasis from colon carcinoma at 11 years after the initial operation managed by lymph node resection and chemoradiation: A case report and a review of the literature

INTRODUCTIONLymph node metastasis from colorectal cancer after a disease-free interval (DFI) of >5 years is extremely rare, and occurs in <0.6% cases.PRESENTATION OF CASEA 60-year-old man underwent low anterior resection for sigmoid colon cancer. The lesion was an adenocarcinoma with no lymph node metastasis of Stage II. At 9 years after the colectomy, he was diagnosed with prostate cancer and was treated with radiation and hormonal therapies; at 11 years, he exhibited suddenly elevated carcinoembryonic antigen levels. Computed tomography (CT) and positron emission tomography-CT revealed a 2.0-cm para-aortic lymph nodes swelling invading the small intestine. These lymph nodes and the affected segment of the small intestine were resected, and histopathology of the resected specimen confirmed a metastatic tumor. The patient was administered radiation therapy after 22 cycles of 5-fluorouracil, oxaliplatin and leucovorin. He however presented with a residual lesion in the para-aortic lymph node, but currently, he has been symptom free for 4 years.DISCUSSIONA review of the literature indicates that the median survival of all previously reported patients is 12 months, and that colon cancer with a long DFI might be a slow growing. One of these patients and our patient both had received radiation and/or hormonal therapy for another cancer, which probably impaired their immune systems, thus resulting in metastatic tumors.CONCLUSIONWe report a case of lymph node metastasis after a DFI of >5 years and review relevant literature to assess the significance and possible reasons for delayed colorectal cancer metastases.