410MO - Pattern and treatment outcomes of second primary cancer (SPC) of the upper aerodigestive tract (UADT) in head and neck squamous cell carcinoma (HNSCC) survivors: A multi-center retrospective cohort study with long-term follow-up

Background

HNSCC survivors have the highest risk to develop SPC among all cancer survivors. This study aimed to evaluate the epidemiology and prognosis of SPC in HNSCC, focusing on the UADT.

Methods

All HNSCC patients diagnosed during 2000-2014 in 2 tertiary oncology centers in Hong Kong were reviewed. Survivors developing SPC of UADT were included and restaged with AJCC 8th. Kaplan-Meier method and Cox regression were used for overall survival (OS) and multivariable analysis.

Results

At a median follow-up of 17.8 years, 593 out of 3145 HNSCC patients developed SPC. 118 had SPC of the UADT. The median age was 61.5 year-old [interquartile range (IQR) 54-69]. 80% were male and 85% were smokers. Leading sites for SPC of UADT were esophagus (38%) and oral cavity (37%), followed by oropharynx (9%), nasal cavity (8%), hypopharynx (6%) and larynx (2%). 90% of patients presented with symptoms. 56% presented at stage III/IV. Median time from diagnosis of HNSCC to diagnosis of SPC was 72 months (IQR 32-123). It was 85 months for oral cavity and 57 months for esophagus. 66% underwent radical treatments. 37% had treatment limitations due to previous RT. Median OS was 12 months. 1-year and 3-year OS were 50% and 35% respectively. On multivariate analysis, esophageal SPC (HR 2.6, 95% CI 1.2 - 5.8, p=.02), advanced stage (HR 3.8, 95% CI 2.2-6.6, p<.001) and smoker (HR 4.8, 95% CI 1.5-15.7, p =.01) were poor prognostic factors. Compared to the population data from SEER, esophageal and oral cavity SPC patients had much shorter survival, especially in the locally advanced or metastatic subgroups. Table: 410MO

Conclusions

SPC of UADT in HNSCC survivors had poor treatment outcomes. Over 1/3 of patients could not undergo treatments of radical intent. Time-sensitive surveillance and early cancer awareness education programs for early detection of SPC in HNSCC survivors are warranted to help improve the survival outcomes.

Clinical trial identification

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.