Abstract
AIM: Primary liver cancer is usually diagnosed at advanced stages with distant metastasis, underlying the high metastatic rate and mortality in patients. This study aimed to analyse the metastatic patterns and prognosis of primary liver cancer, and its relationship with age and several other factors, such as histological variants, TNM stage, and grade. METHODS: We included data from 5274 patients from the Surveillance, Epidemiology, and End Results (SEER) database of the American National Cancer Institute diagnosed with primary liver cancer with metastatic disease between 2010 and 2015. The correlation between the metastatic patterns of primary liver cancer and age was evaluated. The hazard ratio (HR) and 95% confidence intervals (CI) for overall survival were calculated by applying univariate Cox analysis, while the correlation between the metastatic patterns and age was analysed by applying multivariate Cox analysis. We also plotted Kaplan-Meier curves to illustrate the correlation between overall survival (OS) and various factors. RESULTS: Several factors were associated with poorer prognosis, including age>60 years, histologic type of spindle cell variant, higher grade, no surgery, tumour size ≥ 1 cm, and lung metastasis. The rate of metastasis increased with age. Older patients (> 50 years) were prone to bone metastasis, while less likely to have lung metastasis compared with younger patients (< 50 years). Patients with lung metastasis had a higher risk of being diagnosed with metastasis in other locations. Furthermore, surgery significantly reduced mortality and primary site surgery in particular, mitigated the risk of bone and lung metastases. CONCLUSIONS: Our study shows the correlation of prognosis and metastatic patterns with age and several other factors. The findings can hopefully provide knowledge that will allow a better diagnosis and management of elderly patients with primary liver cancer.