Duodenal Metastasis from Colorectal Cancer: A Case Report

Abstract

Background: The occurrence of metastatic colon lesions in various organs has been documented extensively in the literature. The liver, lungs, and bones are the most frequently affected sites. Metastasis in the duodenum due to colon cancer is an infrequent occurrence. Case Presentation: We present a detailed case report of a 65-year-old female patient diagnosed with metastatic colon cancer to the duodenum. The patient initially underwent extended right hemicolectomy for stage III low-grade adenocarcinoma of the colon. Adjuvant chemotherapy was administered, resulting in a period of apparent remission. However, in 2020, the patient experienced elevated tumor marker levels, prompting further investigations. Endoscopy revealed an irregular mass infiltrating the muscle layer in the duodenum, confirming malignant involvement. The patient underwent curative distal gastric duodenectomy, with pathology results indicating a colonic origin of the tumor. The patient received first-line palliative chemotherapy with FOLFOX rechallenge and the addition of AVASTIN. Several cycles of chemotherapy were completed, with satisfactory tumor response observed in follow-up PET scans. Maintenance therapy was initiated after achieving disease-free status on CT scans. However, in October 2022, the patient exhibited increasing tumor marker levels and new findings on PET scan, leading to the initiation of second-line palliative therapy with FOLFIRI and ramucirumab. The patient has received multiple cycles of second-line therapy, with the most recent PET scan in February 2023 showing a favorable treatment response, including a decrease in the size of existing nodes and no identification of new lesions. Conclusion: In conclusion, this case exemplifies the journey of a patient with stage 3 colon cancer who initially responded well to surgery and adjuvant chemotherapy, but experienced subsequent relapse in the duodenum. Despite surgical intervention and palliative chemotherapy, the patient developed metastasis in the liver, lung, and multiple lymph nodes.