Background: Small bowel adenocarcinoma (SBA) is rare despite the fact that the small bowel represents the longest part and has the largest surface of all alimentary tract sections. Its incidence is 50-fold lower than that of colorectal carcinoma. It is often diagnosed at an advanced stage due to atypical and late symptoms, its low index of suspicion, difficult endoscopic access and poor detection by radiological imaging, resulting in impaired outcome. Due to its rarity and being molecularly a unique intestinal cancer, data regarding its optimal management are relatively sparse.
Material and methods: A PubMed search was performed to identify relevant manuscripts that were recently published. Emerging data regarding the pathogenesis, the diagnosis and the treatment of SBA that resulted from recent research are discussed in this comprehensive review.
Results: Genomic analysis has demonstrated that SBA is a molecularly unique intestinal cancer. Double balloon enteroscopy and capsule endoscopy are novel techniques which may result in earlier diagnosis and consequently in improvement of the generally poor prognosis. For clinically localized disease, the quality of surgery has recently been defined, with removal of at least 8-10 lymph nodes correlating with improved prognosis. Moreover, adjuvant chemotherapy seems to improve outcome of stage III disease. The combination of a fluoropyrimidine and oxaliplatin appears to be the most effective systemic chemotherapy for disseminated disease. Genomic profiling can identify potentially targetable genomic alterations in a significant proportion of SBA patients. The role of administration of targeted agents or immune checkpoint inhibitors is still unknown and subject of ongoing clinical trials. In the common case of peritoneal metastases, recent studies have shown that cytoreductive surgery and intraoperative hyperthermic intraperitoneal chemotherapy may be an attractive treatment option in selected patients.
Conclusions: SBA is a rare and unique malignancy, whose diagnostic approach and treatment are evolving, resulting in improved outcome.