Case Series Analysis of Diagnosis and Treatment of Gastrointestinal Metastasis in Lung Cancer Patients.

Objective: This study was designed to investigate the clinical, pathological, endoscopic, and imaging characteristics of gastrointestinal metastasis in patients with lung cancer. Methods: The clinical data of 20 patients with primary lung cancer with gastrointestinal metastasis. Results: This study included sixteen men and four women, ranging in age from 31 to 75 years. The time interval from the diagnosis of lung cancer to the detection of gastrointestinal metastasis ranged from 13 to 142 months. The most common sites of metastasis were the small intestine (eight cases), colon (four cases), and upper gastrointestinal tract (eight cases). The major symptoms included obstruction, perforation, abdominal pain, abdominal distension, anorexia, and anemia. The predominant pathological type was poorly differentiated adenocarcinoma (seventeen cases). A single ulcer was mostly seen on endoscopy, and some cases showed a slight depression of the intestinal wall. The CT and PET-CT scan revealed bowel wall thickening, intraluminal polypoid masses, and intestinal perforation. Conclusion: Gastrointestinal metastasis of lung cancer is mainly observed in the small intestine, colon, and stomach, and is often detected when severe complications such as gastrointestinal obstruction and perforation occurred. Regular evaluation of gastrointestinal conditions during lung cancer diagnosis and treatment is recommended to improve the diagnostic accuracy and prevent misdiagnosis.