Published online Sep 16, 2023. doi: 10.12998/wjcc.v11.i26.6289
Peer-review started: June 17, 2023
First decision: August 4, 2023
Revised: August 15, 2023
Accepted: August 21, 2023
Article in press: August 21, 2023
Published online: September 16, 2023
Collision tumors of primary malignant lymphoma and adenocarcinoma in the colon are rare. Primary diffuse large B-cell lymphoma (DLBCL)–adenocarcinoma collision tumors are especially rare.
A 74-year-old woman presented with abdominal pain of 1 mo duration. Biopsy under colonoscopy revealed adenocarcinoma of the ascending colon. Subsequently, the patient underwent laparoscopic radical resection of right colon cancer with lymph node dissection. A collision tumor was found incidentally through postoperative pathological sampling. Genetic analysis showed a collision tumor of DLBCL with germinal center B-cell subtype and TP53 mutation, and adenocarcinoma arising in a tubulovillous adenoma in the colon, with BRAF mutation and mutL homolog 1 promoter methylation. The patient died 3 mo after surgery. To our knowledge, this is the 23rd reported case of collision tumor of colorectal adenocarcinoma and lymphoma. The mean age of the 23 patients was 73 years. The most common site was the cecum. There were 15 cases with follow-up data including 11 living and four dead with a 3-year overall survival rate of 71.5%.
Based on pathological and genetic analysis, surgery combined with chemotherapy or chemoradiotherapy may have good therapeutic effects for collision tumor.
Core Tip: Coexisting of primary diffuse large B-cell lymphoma (DLBCL) and adenocarcinoma in the colon are extremely rare. Here, we report a case of collision tumor of primary DLBCL, not otherwise specified with germinal center B-cell subtype and TP53 mutation, and adenocarcinoma arising in a tubulovillous adenoma in the colon, with BRAF mutation and mutL homolog 1 promoter methylation. Definite diagnosis is usually difficult until pathological confirmation. Based on pathological examination and genetic analysis, surgery combined with dose-adjusted chemotherapy or chemoradiotherapy may have good therapeutic effects.