Small bowel tumors: an analysis of tumor-like lesions, benign and malignant neoplasms.

The clinical records of 72 patients with 73 small bowel tumors diagnosed over a period of 25 years were reviewed. The tumors consisted of 23 tumor-like lesions, 17 benign neoplasms and 33 malignant neoplasms, the mean size of which were 2.1 cm, 5.2 cm and 7.7 cm in diameter, respectively. The tumor-like lesions and benign neoplasms were found even in children, while the malignant neoplasms were observed in patients 43 years old or over. The most common tumor-like lesion was aberrant pancreatic tissue. The common benign neoplasms were leiomyoma, lipoma and adenoma. The malignant neoplasms consisted of adenocarcinoma, malignant lymphoma and leiomyosarcoma. Regardless of tumor type or tumor location, the lesions 4 cm or larger often caused abdominal symptoms. Most of the lesions less than 4 cm caused no symptoms, but the malignant lesions of this size in the ileum elicited abdominal symptoms in all patients. The presence of lesions was diagnosed preoperatively in 26.1% of patients with tumor-like lesions, 47.1% with benign neoplasms and 48.5% with malignant neoplasms. Resection was performed in all but one patient with tumor-like lesions and benign neoplasms. Among malignant lesions, the resectability rate was 80.0% for adenocarcinoma and 100% for both malignant lymphoma and leiomyosarcoma. However, the patients with malignant lesions showed a poor prognosis. In conclusion, it is important to recognize small bowel tumors--especially malignant lesions--as a rare but possible cause of abdominal symptoms and thereby to contribute to the early detection and successful management of small bowel tumors.