Second malignant neoplasms in patients under 40 years of age with laryngeal cancer

Objectives/Hypothesis To determine the incidence of second malignant neoplasms (SMN) in patients under 40 years of age with invasive squamous cell carcinoma (SCC) of the larynx. Study Design Retrospective. Methods Using a National Cancer Institute tumor registry database encompassing 1973–1996, the incidence of SMN in patients under 40 years of age with laryngeal cancer was determined and compared with that of the registry's older, more traditional laryngeal cancer population. Median follow-up was 136 months. Results Among the 364 patients under the age of 40 years with laryngeal cancer, 30 (8.2%) had developed a secondary malignancy to date. In comparison, 4876 (21.4%) of 22,786 patients 40 years or older with laryngeal cancer were affected by an SMN. Kaplan-Meier analysis of the younger cohort projected 3.0%, 6.8%, and 10.7% relative risk of developing a SMN at any site over 5-, 10-, and 15-year periods, respectively, after index tumor diagnosis. Similar results for the older cohort were 14.2%, 28.1%, and 39.4% at 5, 10, and 15 years, respectively. Further Kaplan-Meier analysis demonstrated at least a fourfold increased risk for the development of secondary upper aerodigestive tract malignancies among older compared with younger patients. Conclusion Patients under 40 years of age with invasive SCC of the larynx are significantly less likely to develop a second malignancy than their older counterparts.