ObjectiveThe aim of this retrospective study is to evaluate the usefulness of upper gastrointestinal endoscopy and the ValsamouthⓇ by an otolaryngologist in patients with hypopharyngeal cancer to assess the risk. MethodsThe study group comprised 41 patients with untreated hypopharyngeal cancer that was precisely diagnosed by an otolaryngologist using upper gastrointestinal endoscopy and the ValsamouthⓇ at our hospital from January 2016 to December 2017. With upper gastrointestinal endoscopy and the ValsamouthⓇ, the oral cavity, oropharynx, larynx, hypopharynx, and esophagus were observed in this order. Narrow-band imaging, and subsequently, white-light observation were performed. At the hypopharynx, vocalization, and subsequently, the Valsalva maneuver were performed. After observing the esophagus, Lugol chromoendoscopy of the esophagus was performed. ResultsThe mean age of the 38 men and 3 women included in the study was 69.7 ± 10.0 years (range, 51–94 years). As for the T category of hypopharyngeal cancer, T1 cancer was observed in 9 patients, T2 cancer in 14, T3 cancer in 11, and T4 cancer in 7. With vocalization, the grade of visualization in the hypopharynx was 1 in 30 patients (73.2%), 2 in 11 patients (26.8%), and 3 or more in 0 patients (0.0%). With the Valsalva maneuver, the grade of visualization in the hypopharynx was 1 in 1 patient (2.4%), 2 in 15 patients (36.6%), 3 in 8 patients (19.5%), 4 in 11 patients (26.8%), and 5 in 6 patients (14.6%). The grade of visualization in the hypopharynx on average was 1.27 after vocalization and 3.15 after the Valsalva maneuver (p < 0.001). With vocalization, the percentage of patients in whom the entire image of hypopharyngeal cancer could be observed was 0.0% for grade 1 and 18.2% for grade 2. With the Valsalva maneuver, the percentage of patients in whom the entire image of hypopharyngeal cancer could be observed was 0.0% for grade 1, 40.0% for grade 2, 50.0% for grade 3, 86.1% for grade 4, and 100% for grade 5. Synchronous esophageal cancers were detected in 17.1% (7/41) of the patients. The grade of Lugol-voiding lesions was A in 5.6%, B in 52.8%, and C in 41.7%. ConclusionThe examination with upper gastrointestinal endoscopy and the ValsamouthⓇ by an otolaryngologist is feasible in patients with hypopharyngeal cancer. This procedure can detect synchronous esophageal cancer, allowing the risk of metachronous cancer in the head and neck or the esophagus to be recognized after the treatment.