Incidence, endoscopic morphology and distribution of metastatic lesions in the gastrointestinal tract

Metastasis rarely occurs in the gastrointestinal tract (GIT). However, as progress regarding the treatment of cancers has occurred over recent years, the survival time of patients affected by advanced-stage cancers has increased. It could be expected that progressively more cancer patients with gastrointestinal symptoms would be presenting to gastroenterologists for diagnosis and further management. The aim of this study was to reveal the incidence, typical location and morphology of secondary tumors within the GIT.

A retrospective study was conducted at the National Taiwan University Hospital from 1 January 1994 to 31 December 2003 inclusive in order to review the available data pertaining to diagnosed GIT metastases. Only those patients who had been checked by endoscopy and confirmed by histopathology were included. Details regarding patient clinical information, demographic data, treatment, histopathology, and eventual outcome were reviewed, recorded and analyzed.

The incidence of GIT metastases was found to be one upper GIT metastasis per 3847 upper GIT endoscopies and one lower GIT metastasis per 1871 colonoscopies. The common locations for metastases to occur were duodenum and stomach. The general morphology of the observed metastatic lesions of the digestive tract identified them, mostly, as single and primary (mucosa-origin) carcinoma-like lesions. The survival interval from the diagnosis of GIT metastasis to patient death was statistically significantly longer in the aggressive-treatment group compared to the conservative-treatment group (Kaplan-Meier, P = 0.0004).

Although metastatic lesions in the GIT are rare, they do occur. They usually present as single and primary carcinoma-like lesions, with the stomach and duodenum most commonly involved.