891P - Changing landscape of head and neck squamous cell carcinoma (HNSCC) treatment and survival in Thailand: A 13-year multicenter retrospective study of 6,319 patients

Background

HNSCC is a heterogeneous group with diverse incidence and survivals worldwide. Factors such as ethnicity, lifestyle, and healthcare systems contribute to these differences. This study aimed to describe the landscape of HNSCC patient characteristics, treatments, and survival outcomes in Thailand over 13 years.

Methods

We retrospectively analyzed data from a multicenter database of patients with HNSCC treated between 2008 and 2020 in Thailand.

Results

A total of 6,319 patients from 4 large cancer centers were analyzed. Most patients had nasopharynx (NP 33%), oral cavity (OC 23%), oropharynx (OR 17%), larynx (LA 15%), or hypopharynx (HP 8%) as primary sites. The incidence of HPV-related oropharyngeal squamous cell carcinoma had been rising from 13% in 2008 to 42% in 2019-2020. Most patients presented with locally advanced (LA) stage (stage IVa/b 50%, and III 26%), and the proportion of LA stages increased annually. Chemoradiotherapy (CRT) (43%) and surgery (31%) with or without adjuvant (chemo)radiotherapy were the most common definitive treatments. Cisplatin (79%) was most used with CRT, followed by carboplatin (20%) and cetuximab (1%). Local, regional, and distant recurrences were observed in 46%, 19%, and 35% of all patients, respectively. Overall survival (OS) improved annually across all subsites. The use of intensity-modulated radiotherapy (IMRT) increased from 25% in 2008 to 90% in 2019-2020. Patients treated with IMRT had significantly longer OS compared to non-IMRT (HR 0.52, 95% CI 0.46-0.58; p<0.001). Table: 891P

Conclusions

This is the largest study of HNSCC patients in Thailand, highlighting the increasing survival outcomes despite the presentation of locally advanced stages. The growing utilization of IMRT might contribute to the improvement of survival outcomes for HNSCC patients in Thailand.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

The study was funded by the National Research Council of Thailand (NRCT) (Government Research Grant through Mahidol University #3484 (Project #6908)), and the Health Systems Research Institute (HSRI) (grant number 63-140), and the NSRF via the Program Management Unit for Human Resources & Institutional Development, Research and Innovation (grant number B05F650041).

Disclosure

N. Ngamphaiboon: Financial Interests, Personal, Invited Speaker: Roche, MSD, Merck, Eisai; Financial Interests, Personal, Advisory Board: MSD, BeiGene, BMS, Roche, Merck; Financial Interests, Institutional, Research Grant: Pfizer; Financial Interests, Institutional, Local PI: MSD, Roche, RAPT therapeutics, BeiGene, Boehringer Ingelheim Pharmaceuticals; Non-Financial Interests, Other, Safety Monitoring Committee (SMC): Boehringer Ingelheim Pharmaceuticals. All other authors have declared no conflicts of interest.