Clinicopathological analysis of small intestinal metastasis from extra-abdominal/extra-pelvic malignancy.

Background: The metastatic tumors in the small intestine secondary to extra-abdominal/extra-pelvic malignancy are extremely rare. However, the small intestine metastases are extremely prone to misdiagnosis and missed diagnosis due to the lack of specific clinical manifestations and examination methods, thus delaying its treatment. Therefore, in order to improve clinical diagnosis and treatment capabilities, it is necessary to summarize its clinical pathological characteristics and prognosis.

Peutz-Jeghers syndrome without mutation may correlate with less severe clinical manifestations in Chinese patients.

Background: Peutz-Jeghers syndrome (PJS) is an autosomal dominant genetic disease with skin mucosal pigment spots and gastrointestinal (GI) multiple hamartoma polyps as clinical characteristics. At present, it is considered that the germline mutation of gene is the genetic cause of PJS. However, not all PJS patients can be detected germline mutations.