Presentation –

A 65-year-old man (Uncle Bob) is presented with new nausea, vomiting, and abdominal distension 3 years after a total colectomy for Dukes’ B2 adenocarcinoma.

Imaging Findings (CAT) – Small bowel follow-through with barium contrast: Spot views Images obtained from a single-contrast small bowel follow-through demonstrate mildly dilated small bowel loops and two focal points of stenosis in the ileum.

Preliminary Diagnosis – Radiographic evidence demonstrates small bowel obstruction and suggests the presence of invasive submucosal masses.

Such lesions may be caused by:

Metastasis from colonic primary tumor

Primary cancer of the small intestine

Metastasis from another primary or previous tumor

Final Diagnosis – Small bowel obstruction caused by metastasis from colonic adenocarcinoma

This patient presents with clinical and radiographic evidence of small bowel obstruction by two deeply invasive submucosal masses(tumors). Their broad bases form obtuse angles with the surrounding bowel wall, indicating intramural location. The first causes symmetric, almost concentric, narrowing of the lumen while the second is slightly more asymmetric. On fluoroscopy, the masses were not pliable.

At the time of the original resection and staging of adenocarcinoma, three years prior to this presentation, the lesion extended through the colonic serosa without regional lymph node involvement or metastasis, classifying it as Dukes’ B2 adenocarcinoma . Most recurrences occur within the first four years after surgical resection. Although colon cancer most commonly metastasizes to the regional lymph nodes and then to the liver, other sites including lungs, supraclavicular nodes, bone, brain or small intestine may be affected.

Another possibility is a second primary tumor arising from the small intestine. Although malignant tumors of the small intestine are rare (comprising only 3-6% of all gastrointestinal neoplasms), the risk of primary adenocarcinoma of the small bowel is increased following colorectal cancer (6). Adenocarcinomas grow circumferentially with luminal narrowing. The resulting “apple-core” or “napkin-ring” appearance is similar to the appearance of the lesions in this patient.

Other primary tumors of the small intestine such as lymphoma, carcinoid tumors and leiomyosarcomas are less likely. Other tumors which metastasize to the small intestine include melanoma, lung, breast, kidney, pancreas and stomach. In women, ovarian carcinoma is notorious for seeding any surface of the peritoneal cavity, including the small intestine. Given the patient’s history and the morphology of the lesions, metastatic seeding from colon adenocarcinoma is the most likely diagnosis. His chance of surviving more than one year is small.

Resources:

https://www.cancer.gov/

Questions

• What type of cancer does Uncle Bob have? (What is the diagnosis).
• What is the prognosis for Uncle Bob?
• What current treatments are available?
• What are the possible treatments?
• Which treatment do you suggest and why?
• How does the treatment that you have suggested stop cancer?