Analysis of Related Risk Factors and Prognostic Factors of Gastric Cancer with Bone Metastasis: A SEER-Based Study

BACKGROUND: Gastric cancer is among the most common malignant tumors at home and abroad, because its early symptoms are mostly insidious, which leads to distant metastasis when gastric cancer is first diagnosed. The common metastatic sites of gastric cancer are mainly the liver, lung, and peritoneum, but bone metastasis is relatively rare, and the prognosis of gastric cancer bone metastasis is very poor. Therefore, this study is built on the SEER database to analyze the related risk factors of gastric cancer bone metastasis and related factors affecting the prognosis of gastric cancer patients, aiming at improving clinicians' understanding of clinical diagnosis and prognosis of bone metastasis of gastric cancer, thus reducing misdiagnosis and missed diagnosis. METHODS: The SEER database was collected to screen out patients with gastric cancer bone metastases and nonbone metastases matched with them from 2010 to 2016, and the Kaplan-Meier method was used to draw survival curves, and the comparison between survival curves was performed by Log-rank test to analyze the overall survival of the two groups of patient's time. Logistic regression analysis was used to analyze the related risk factors of gastric cancer bone metastasis, and the Cox regression proportional hazard model was used to analyze the relationship between gastric cancer bone metastasis and patient prognosis. RESULTS: Using Kaplan-Meier survival curve to analyze the 1, 3, and 5-year survival rates of gastric cancer patients with bone metastasis and non-metastasis groups were 14.2%, 1.8%, 0.6% and 71.4%, 44.3%, 36.4%, respectively; the average survival rate of the metastatic group was The time was 4.0 months (95%CI: 3.475~4.525), and the average survival time of the non-metastatic group was 30.0 months (95%CI: 26.778~33.222). The difference between the two groups was statistically significant (χ(2) = 1076.866, P < 0.001). Multivariate logistic regression analysis showed that race (P = 0.007, OR = 1.296), grade (P < 0.001, OR = 0.575), marital status (P < 0.001, OR = 0.040), tumor size (P = 0.006, OR = 0.752), TNM stage (P < 0.001), T stage (P = 0.023, OR = 0.882), and M stage (P < 0.001, OR = 44.958) are independent risk factors for gastric cancer bone metastasis. The Cox univariate analysis suggests that gastric cancer bone metastasis is a risk factor for the prognosis of gastric cancer patients. The Cox multivariate analysis validates that gastric cancer bone metastasis (HR = 0.584, 95% CI: 0.497~0.688, P < 0.001) is independent of the overall survival rate of gastric cancer patients. CONCLUSIONS: Race, grade, marital status, tumor size, TNM stage, T stage, and M stage are independent risk factors for gastric cancer bone metastasis; and gastric cancer bone metastasis is an independent risk factor that affects the prognosis of gastric cancer patients. Therefore, for such high-risk groups, large range screening of the above indicators can effectively improve the prognosis of gastric cancer patients to a certain extent.