Endoscopic screening of the upper gastrointestinal tract for second primary tumors in patients with head and neck cancer in a Western country

Background: Patients with head and neck squamous cell carcinoma (HNSCC) relatively frequent develop second primary tumors (SPTs) in the esophagus. Endoscopic screening could lead to timely detection of SPTs in early stages and therefore improves the survival. Methods: We performed a prospective endoscopic screening study in patients with HNSCC in a Western country. Patients with curably treated HNSCC diagnosed January 2017 to July 2021 were included. Routine imaging for HNSCC consisted of flexible transnasal endoscopy with PET/CT or MRI-scan, depending on primary HNSCC location. Screening was performed synchronously(<6 months) or metachronously (≥6 months) after HNSCC diagnosis. The primary outcome was prevalence of SPTs, defined as presence of esophageal high-grade dysplasia or squamous cell carcinoma. Results: We included 202 patients (81% male, mean age 65 years) and performed 250 screening endoscopies. HNSCC was located in the oropharynx(32%), hypopharynx(26%), larynx(22%), and oral cavity(19%). Endoscopic screening was performed within 6 months(34%), 6 months to 1 year(8%), 1 to 2 years(34%), and 2 to 5 years(24%) after HNSCC diagnosis. We detected 11 SPTs in 10 patients(5.0%, 95%CI: 2.4-8.9%) during synchronous(6/85) and metachronous screening(5/165). Most SPTs were detected in early stages(91%) and treated with curative intent with endoscopic resection(80%). No SPTs in screened patients were detected with routine imaging for HNSCC before endoscopic screening. Conclusion: In 5% of patients with HNSCC, an SPT was detected with endoscopic screening. Endoscopic screening should be considered in a selection of HNSCC patients to detect early-stage SPTs, based on highest SPT-risk and life expectancy depending on HNSCC and comorbidities.