Leiomyosarcoma presenting aneurysmal dilatation of the jejunum on CT

The forgotten appearance of metastatic melanoma in the small bowel

BACKGROUND

Melanoma is the most aggressive form of skin cancer, with a tendency to metastasise to any organ of the human body. While the most common body organs affected include liver, lungs, brain and soft tissues, spread to the gastrointestinal tract is not uncommon. In the bowel, it can present with a multitude of imaging appearances, more rarely as an aneurysmal dilatation. This appearance is classically associated with lymphoma, but it has more rarely been associated with other forms of malignancy.

CASE PRESENTATION

We report a case series of three patients with aneurysmal dilatation in the small bowel (SB) confirmed to be due to metastatic melanoma (MM). All patients had non-specific symptoms; most times being attributed initially to causes other than melanoma. On CT the identified aneurysmal SB dilatations were diagnosed as presumed lymphoma in all cases. In two cases, the aneurysmal dilatation was the first presentation of metastatic disease and in two of the cases more than one site of the gastrointestinal tract was concomitantly involved. All patients underwent surgical resection with histological confirmation of MM.

CONCLUSIONS

Recognition of unusual SB presentation of MM, such as aneurysmal SB dilatation, is important to expedite diagnosis, provide appropriate treatment, and consequently improve quality of life and likely survival of these patients. As the most common cancer to metastasise to the SB and as a known imaging mimicker, MM should remain in any radiologist's differential diagnosis for SB lesions with aneurysmal dilatation.

A Stromal Tumor Presenting as a Pseudoaneurysmal Dilation of the Small Bowel Mimicking a Lymphoma on FDG PET/CT

ABSTRACT

An 84-year-old woman visited our hospital with hematochezia for 1 month. Abdominal CT and FDG PET/CT showed local thickening of the small intestine, resembling an intestinal aneurysmal dilatation. Thus, a lymphoma was suspected, and surgical resection was performed. The final pathology revealed an exophytic small bowel stromal tumor with perforation, causing pseudoaneurysmal dilation of the small bowel. This case emphasized the importance of considering a small bowel stromal tumor when faced with similar FDG PET/CT findings.