Analysis of gastrointestinal metastasis of primary lung cancer: Clinical characteristics and prognosis.

The prevalence of gastrointestinal metastasis of lung cancer is low. The aim of the present study was to analyze the frequency and clinical characteristics of metastases to the gastrointestinal tract by retrospectively assessing the clinical records of 2,066 patients with lung cancer. A total of 7 patients (0.33%) were diagnosed with gastrointestinal metastasis, including 4 patients with adenocarcinoma, 1 patient with large cell carcinoma and 2 patients with pleomorphic carcinoma. Furthermore, 3 of the patients presented with small bowel metastases, 2 with gastric metastases, 1 with large bowel metastasis and 1 with metastasis of the appendix. The mean time between the diagnosis of the lung tumors and the identification of gastrointestinal metastasis was 13.5 months (range, 3-49 months). The mean time between the identification of the gastrointestinal metastasis and mortality was 100.6 days (range, 21-145 days). In conclusion, the prognosis of patients with recurrence in distant organs, including the gastrointestinal tract, may be worse than patients with recurrence in distant organs, excluding the gastrointestinal tract, particularly those with symptomatic gastrointestinal metastasis. Therefore, the presence of clinical gastrointestinal metastasis may be life threatening; comprehensive evaluations are required to detect and monitor gastrointestinal metastasis during follow-up.