Second malignant neoplasms in patients with head and neck squamous cell carcinomas

Area of Science:

• Oncology
• Epidemiology
• Head and Neck Cancer Research

Background:

• Second malignant neoplasms (SMN) represent a significant concern for patients treated for primary cancers.
• Head and neck squamous cell carcinomas (HNSCC) are associated with a substantial risk of developing subsequent primary tumors.

Purpose of the Study:

• To analyze the incidence and risk of second malignant neoplasms (SMN) in patients with squamous cell carcinomas of the oral cavity, oropharynx, hypopharynx, and larynx.
• To compare the incidence of SMN between different subsites within the head and neck region.

Main Methods:

• Retrospective analysis of 714 patients diagnosed with HNSCC.
• Minimum follow-up of 3.5 years, accumulating 2,540 person-years at risk.
• Actuarial methods were used to calculate the annual incidence of SMN.

Main Results:

• A total of 84 SMN (10 synchronous, 74 metachronous) were diagnosed in 81 patients.
• The overall relative risk for SMN was 2.4, with an annual incidence of 3.5%.
• Oral cavity and oropharyngeal tumors showed a higher annual SMN incidence (4.0% and 3.8%) compared to laryngeal cancer (2.1%, p < 0.013 and 0.017).

Conclusions:

• Patients with HNSCC have a notable risk of developing SMN, which becomes a greater concern than loco-regional relapse after 3 years.
• The incidence of SMN varies by primary tumor subsite, with oral cavity and oropharynx cancers posing a higher risk.
• Factors such as sex, age, or stage of the initial tumor did not significantly impact SMN incidence.