Simultaneous Head and Neck and Lung Cancers: Implications and Therapeutic Management Timing.

[OBJECTIVES] This study aims to describe the characteristics of patients with simultaneous head and neck squamous cell carcinomas (HNSCCs) and lung cancer and to assess the impact of diagnosis-to-treatment interval (DTI) and treatment choices on outcomes.

[DESIGN AND SETTING] A bicentric retrospective observational study conducted between 2003 and 2020 in two tertiary referral academic hospitals.

[PARTICIPANTS] Forty-three patients diagnosed with both HNSCC and lung cancer within 1 month were compared to a 1:2 control group of patients diagnosed with HNSCC alone. The groups were matched by tumour location, TNM stage and treatment centre. Multivariate analysis was used to assess factors influencing DTI, and survival analysis was conducted using the Kaplan-Meier estimator.

[MAIN OUTCOME MEASURES] Primary outcomes included DTI and overall survival.

[RESULTS] Patients with simultaneous cancers were predominantly male (84%) with heavy smoking histories. Most HNSCC cases (84%) were diagnosed at advanced stages (III/IV), while lung cancers were predominantly early stage (I-II). Patients with simultaneous cancers had significantly longer DTIs (median 43 days, IQR [32.8-85.8]) compared to controls (28 days, IQR [19.0-38.0]) (p < 0.001; HR = 0.35, p = 0.0001). As expected, overall survival was markedly worse for patients with simultaneous cancers (median 17.8 months, 95% CI [12.6-31.0]) versus controls (56.5 months, 95% CI [38.4-], p < 0.001).

[CONCLUSION] Prolonged DTI may contribute to the poorer survival outcomes in patients with simultaneous cancers. Strategies to reduce delays, such as performing concurrent bronchoscopy and endoscopy, should be explored.