The rising rate of nonsmokers among laryngeal carcinoma patients: Are we facing a new disease?

Objectives/hypothesis: Laryngeal squamous cell carcinoma (SCC) is strongly associated with tobacco smoking. With the rising awareness of tobacco's adverse health effects, we have witnessed a global decrease in tobacco use. Nevertheless, laryngeal SCC remains prevalent and includes a subset of patients lacking the traditional risk factors.
Study Design: A two-center retrospective cohort.
Methods: Medical records of patients diagnosed with laryngeal SCC between 2009 and 2016 were reviewed. Data collected included demographics, smoking status, and tumor site. Patients who have never smoked were designated as nonsmokers.
Results: The study included 330 patients with laryngeal SCC, of whom 75 (22.7%) were nonsmokers; this rate was relatively similar for each of the two institutions independently (21.9% and 25%). There were 285 patients with glottic SCC and 45 with supraglottic SCC. All nonsmoking patients in this cohort had glottic SCC, representing 26.3% (75/285) of the glottic SCC cases. The rate of female patients was significantly higher among nonsmokers. Of the patients with glottic SCC, females represented 25.3% (19/75) of the nonsmokers compared with 12.4% (26/210) of the smokers (P = .008). Mean age at diagnosis was 60.2 ± 17.5 years for nonsmoking glottic SCC patients and 63.6 ± 12.4 years for smokers (P = .280). However, nonsmokers demonstrated a distinct age distribution pattern. Nonsmoking females with glottic SCC demonstrated a bimodal age distribution pattern; 73.7% (14/19) were age <40 years or >75 years at diagnosis.
Conclusions: The rate of laryngeal SCC in nonsmokers is higher than what has previously been reported, representing a growing proportion, and may suggest a shift in etiology. Knowing that laryngeal SCC in nonsmokers predominantly affects the glottis, and that females and age extremities are more vulnerable, the traditional screening paradigm should be revised.
Level of Evidence: 4 Laryngoscope, 130:E108-E115, 2020.
(© 2019 The American Laryngological, Rhinological and Otological Society, Inc.)