Comparison of survival between adolescent and young adult vs older patients with hepatocellular carcinoma

Abstract

Background: Due to the special clinical features and biologic characteristics of adolescent and young adult (AYA) cancers, AYA cancers are different from cancers in children and elderly individuals. However, there are few reports on AYA hepatocellular carcinoma (HCC).

Aim: To investigate the overall survival (OS) of AYA (15-39 years) and elderly (40-74 years) patients with HCC.

Methods: The data of all the HCC cases were extracted from the Surveillance, Epidemiology, and End Results database from 2004 to 2015 and were then divided into two groups based on age: AYA group (15-39 years) and older group (40-74 years). Kaplan-Meier curves and log-rank tests were used to compare the OS of the two groups. Propensity score matching (PSM) was employed to analyze the OS difference between the two groups. The Cox proportional hazards regression model was used to perform multivariate analysis to explore the risk factors for OS of HCC patients.

Results: Compared to elderly cancer patients, AYA patients with HCC had a worse Surveillance, Epidemiology, and End Results stage, including the distant stage (22.1% vs 15.4%, P < 0.001), and a more advanced American Joint Committee on Cancer (AJCC) stage, including AJCC III and IV (49.2% vs 38.3%, P < 0.001), and were more likely to receive surgery (64.5% vs 47.5%, P < 0.001). Before PSM, the AYA group had a longer survival in months (median: 20.00, interquartile range [IQR]: 5.00-62.50) than the older group (median: 15.00, IQR: 4.00-40.00) (P < 0.001). After PSM, the AYA group still had a longer survival in months (median: 21.00, IQR: 5.00-64.50) than the older group (median: 18.00, IQR: 6.00-53.00) (P < 0.001). The Cox proportional hazards regression model showed that advanced age (hazard ratio [HR] = 1.405, 95%CI: 1.218-1.621, P < 0.001) was a risk factor for OS of HCC patients. In the subgroup analysis, the Cox proportional hazards regression model showed that in AJCC I/II HCC patients, advanced age (HR = 1.749, 95%CI: 1.352-2.263, P < 0.001) was a risk factor for OS, while it was not a risk factor in AJCC III/IV HCC patients (HR = 1.186, 95%CI: 0.997-1.410, P = 0.054) before PSM. After PSM, advanced age (HR = 1.891, 95%CI: 1.356-2.637, P < 0.001) was still a risk factor for OS in AJCC I/II HCC patients, but was not a risk factor for OS in AJCC III/IV HCC patients (HR = 1.192, 95%CI: 0.934-1.521, P = 0.157) after PSM.

Conclusion: AYA patients with HCC have different clinical characteristics from older adults. In different AJCC stages, the two groups of patients have different OS: In AJCC I/II HCC patients, advanced age is a risk factor for OS, but it is not a risk factor for OS in the AJCC III/IV HCC patient group.

Keywords: Adolescent and young adults; Hepatocellular carcinoma; Older adults; Overall survival; Propensity score matching; Risk factor.

Figure 1

Forest map of multivariate analysis of overall survival in patients with hepatocellular carcinoma. All variables were statistically significant. Advanced age, black ethnicity, advanced American Joint Committee on Cancer stage, and advanced grade are risk factors for OS of HCC patients; female gender, other races, married status, surgery, radiation, and chemotherapy are protective factors for OS of HCC patients. AJCC: American Joint Committee on Cancer; Grade I: Well differentiated; Grade II: Moderately differentiated; Grade III: Poorly differentiated; Grade IV: Undifferentiated; OS: Overall survival; HCC: Hepatocellular carcinoma.

Figure 2

Comparison of overall survival in hepatocellular carcinoma patients between adolescent and young adult and older groups before and after propensity score matching (A and B). AYA: Adolescent and young adult; OS: Overall survival.

Figure 3

Difference in overall survival between the two groups of patients in different American Joint Committee on Cancer stages before and after propensity score matching using Kaplan-Meier curves and the log-rank tests. A and B: Comparison of overall survival between adolescent and young adult and older hepatocellular carcinoma patients in AJCC stage I/II before and after propensity score matching; C and D: Comparison of overall survival between adolescent and young adult and older hepatocellular carcinoma patients in AJCC stage III/IV before and after propensity score matching (C and D). AYA: Adolescent and young adult.