Treatment Outcomes and the Safety of Chemoradiotherapy With High-Dose CDDP for Elderly Patients With Head and Neck Squamous Cell Carcinoma: A Propensity Score Matching Study

Abstract

Objective: We aimed to compare the outcomes and safety of chemoradiotherapy (CRT) between elderly and non-elderly patients with head and neck squamous cell carcinoma (HNSCC). It is difficult to assess the causal effect of age because of possible differences in general conditions among individuals. Therefore, we adjusted the background factors of elderly and non-elderly patients using propensity score matching (PSM). Methods: A total of 146 patients with HNSCC who received CRT were divided into an elderly (≥70 years, n = 35) and non-elderly group (<70 years, n = 111). Pre-treatment characteristics, including the performance status, Charlson comorbidity index, body mass index, primary site, and TNM stage were adjusted by PSM. We compared the outcomes and safety of CRT with high-dose single-agent cisplatin (CDDP) as well as outcomes following recurrence between the groups, before and after PSM. Results: The total dose of CDDP administered during CRT was significantly lower in the elderly group before PSM. However, it became comparable to the non-elderly group and adverse events did not differ between the groups following PSM, resulting in a comparable CRT completion rate. Overall-, disease specific-, and progression-free survivals of elderly patients were comparable to those of non-elderly patients following PSM. In contrast, elderly patients with recurrence could receive fewer salvage treatments than their non-elderly counterparts, resulting in worse survival. Conclusions: CRT with high-dose CDDP is safe and effective for the treatment of elderly patients with HNSCC. However, salvage treatments can be rarely conducted for elderly patients with a recurrence, considering a deterioration of their general condition.

Keywords: chemoradiotherapy; elderly patients; head and neck squamous cell carcinoma; high-dose single-agent cisplatin; propensity score matching.

Figure 1

Flow diagram of study participants. A total of 870 HNSCC patients were treated in our institutions. Of the 157 patients treated with concurrent CRT using high-dose CDDP, we excluded 11 patients who received neoadjuvant chemotherapy. A total of 146 patients were included in the study.

Figure 2

The overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS) according to the age, before and after propensity score matching (PSM). Before PSM, the OS (A) and DSS (B) are significantly worse in elderly patients than that in non-elderly patients (60.2% vs. 90.5%, p = 0.002 and 73.3% vs. 93.3%, p = 0.010, respectively), while there are no significant differences in PFS (C) (68.6% vs. 76.0%, p = 0.391). Following PSM, there are no significant differences in the OS (D), DSS (E), and PFS (F) between the patients (56.4% vs. 89.3%, p = 0.052, 72.1% vs. 89.3%, p = 0.127 and 66.7% vs. 69.1%, p = 0.940, respectively).

Figure 3

The overall survival (OS) and disease specific survival (DSS) of recurrent patients according to age following propensity score matching (PSM). (A) The 1-year OS rate in elderly patients (22.2%) is significantly worse than that in non-elderly patients (91.7%) (p < 0.001). (B) The 1-year rate of DSS in elderly patients (22.2%) is significantly worse than that in non-elderly patients (91.7%) (p < 0.001).