The incidence of esophageal second primary cancer in head and neck cancer patients.

This study aims to investigate the correlation between esophageal second primary neoplasm (ESPN) in head and neck cancers. Panendoscopy findings of ESPN can guide clinicians in timely interventions and improve patients' outcomes. We performed a retrospective cohort study in Linkou Chang Gung Memorial Hospital, and 365 patients who met the criteria from 2015 to 2021 were enrolled. We collected the lifestyle habits and panendoscopy report after the HNC was diagnosed. Of 365 HNC patients, 37 (10.1%) had ESPNs, which included low dysplasia, high dysplasia, squamous cell carcinoma in situ and squamous cell carcinoma. We found that alcohol (P = .004) and areca-quids (AQs) consumption (P = .003) had significant differences in different HNC subsites. Oral cavity cancers had the highest association with alcohol and AQs consumption. Hypopharyngeal cancer has the highest ESPN incidence with highest odds ratio (OR = 13.3, P < .001), followed by oropharynx, larynx, and oral cavity. In addition, we found that alcohol (P = .002) and cigarette consumption (P = .040) were associated with the ESPN development. Other panendoscopy findings such as gastroesophageal reflux disease, esophageal mucosa break, gastritis ulceration, and gastritis showed insignificant correlations with the occurrence of ESPN. Half of the ESPN were found within 24 months after the diagnosis of HNC, especially for hypopharyngeal cancer, in which ESPN even occurs within 12 months of the diagnosis of primary tumor. Routine panendoscopy for patients with HNC is highly advised, and our study suggests having intensive surveys in the first 24 months after the diagnosis of primary HNC; especially for hypopharyngeal cancer. This study was reported in strict compliance with the strengthening the reporting of observational studies in epidemiology (STROBE) guideline.