摘要
BACKGROUND Mucosa-associated lymphoid tissue (MALT) lymphoma is a subtype of non-Hodgkin lymphoma that is mainly involved in the gastrointestinal tract. Thesynchronous occurrence of colonic MALT lymphoma and adenocarcinoma in thesame patient is extremely rare. We here report a case of synchronous colonicMALT lymphoma found on surveillance colonoscopy five months after surgeryand chemotherapy for sigmoid adenocarcinoma.CASE SUMMARY A 67-year-old man was admitted because of hematochezia for two months.Colonoscopy suggested a colonic tumor before hospitalization. Abdominalcomputed tomography (CT) revealed local thickening of the sigmoid colon. Thepatient underwent a left hemicolectomy with local lymph node dissection. Thehistopathology revealed moderately differentiated adenocarcinoma and partiallymucinous adenocarcinoma. The pTNM stage was T3N1Mx. The patient receivedchemotherapy with six cycles of mFOLFOX6 after surgery. Colonoscopy wasperformed five months later and revealed single, flat, polypoid lesions of thecolon 33 cm away from the anus. Subsequently, the patient underwent endoscopic mucosal resection for further diagnosis. The pathological diagnosis was MALTlymphoma. Positron emission tomography /CT suggested metastasis. The patientrefused further treatment and died ten months later.CONCLUSION Colonic MALT lymphoma may occur after surgery and chemotherapy foradenocarcinoma as a synchronous malignancy. Regular surveillance colonoscopyand careful monitoring after surgery are critical.
