365P - Radiotherapy treatment outcomes and treatment compliance of nasopharyngeal cancer patients in Sabah: A retrospective analysis

Background

Nasopharyngeal carcinoma (NPC) is one of the most common malignancies in Malaysia and the incidence rate is high in the state of Sabah. Patients in Sabah are known to have limitations to access the healthcare services in the state. The purpose of this study is to examine the survival results, failure patterns, and compliance rate of patients with nasopharyngeal cancer who received radical radiotherapy with or without chemotherapy in Sabah.

Methods

A retrospective analysis was performed on patients diagnosed with stage I-IVA (AJCC staging 8^th edition) NPC and treated with radiotherapy between the years of 2017-2019 in Sabah Women and Children's Hospital. The Kaplan-Meier method was used for survival analysis and differences in survival according to AJCC stage was compared using the log-rank test.

Results

A total of 140 patients were treated during this period. Most of them presented late at diagnosis, stage III (39%) and stage IVA (40%). Majority of them were treated with IMRT technique (85%). The compliance rate to radiotherapy was 96%. The 3-year overall survival (OS), disease-free-survival (DFS), local-failure-free survival (LFFS), regional-failure-free survival (RFFS), distant-failure-free survival (DFFS), of NPC patients in this study are 70%, 61%, 83%, 84%, and 67% respectively. The LFFS was significantly different between T stages (P value = 0.003) and T4 stage had the lowest rate of 3-year LFFS (65%). The RFFS was significantly different between N stages (P value = 0.013) and the 3-year RFFS probability for N3 stage was markedly lower than the rest (63%). The DFFS was significantly different between N stages (P-value < 0.001) and the 3-year DFFS probability decreased as N stage increased.

Conclusions

The 3-year OS and 3-year DFS rates in our study are comparable to those in peninsular Malaysia. The LFFS for T1-T3 stages is high. However, LFFS is low in T4 disease and DFFS is significantly low in N3 disease. Hence prospective studies are needed to determine if this group of patients may benefit from an intensified systemic treatment. Despite facing many challenges to access healthcare in Sabah, NPC patients in the state have a remarkably high compliance rate to radiotherapy treatment.

Clinical trial identification

NMRR ID-23-00055-E3N; RSCH ID-22-02599-GSk.

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.