Concurrent occurrence of terminal ileum carcinoid tumor and cecal adenocarcinoma: A collision tumor or composite tumor?

Concurrent small bowel adenocarcinoma and carcinoid tumor in Crohn's disease--case report and literature review

Adenocarcinomas of the large and small bowel, as well as intestinal carcinoid tumors have been reported at increased rates in Crohn's disease. We herein report a rare case of concurrent adenocarcinoma and carcinoid tumor of the small bowel presenting as intestinal obstruction and found incidentally at laparotomy in a 55 year old male with longstanding ileal Crohn's disease. We performed a Medline Pubmed search for cases of synchronous or composite adenocarcinoma and carcinoid tumor in the setting of Crohn's disease and identified four similar cases. Concurrent adenocarcinoma and carcinoid tumor occurred both in newly diagnosed and longstanding Crohn's disease, most commonly involved the terminal ileum and presented with symptoms mimicking Crohn's disease. Diagnosis was made incidentally at laparotomy in all cases. Lymph node involvement was variable. Clinicians should be aware of this rare entity for expeditious surgical intervention.

Mixed adenocarcinoma-carcinoid (collision tumor) of the appendix

OBJECTIVE

To report a case of mixed adenocarcinoma and carcinoid in the gastrointestinal tract.

CLINICAL PRESENTATION AND INTERVENTION

A 52-year-old man presented with a mass at the base of the appendix. On microscopic examination of the tumor, mixed adenocarcinoma and carcinoid was identified. The carcinoid component was insular/trabecular in morphology, and the epithelial component revealed mucinous adenocarcinoma. Morphologically and immunohistochemically the 2 components showed a clear-cut distinction, without any intervening intermediate cell population. The adenocarcinomatous component displayed omental deposit and metastasis to the regional lymph nodes. One year later, the patient developed multiple metastatic deposits of adenocarcinoma in the liver, rectus muscle, ileum and sigmoid colon.

CONCLUSION

This tumor had an aggressive clinical course and behaved more like adenocarcinoma than carcinoid.