Optical coherence tomography for the staging of tumor infiltration in superficial esophageal squamous cell carcinoma

BackgroundOptical coherence tomography (OCT) is a noninvasive technology that can produce high-resolution cross-sectional images in real-time without acoustic coupling, enabling precise assessment of tumor invasion in superficial esophageal squamous cell carcinomas (SESCCs).ObjectiveTo elucidate the usefulness of in vivo OCT for the staging of SESCCs.DesignA single-center, prospective study in 2 phases: phase I to establish the OCT criteria classified into 3 categories (epithelium or lamina propria mucosa [EP/LPM], muscularis mucosa [MM], submucosa [SM]) and phase II to evaluate these criteria.SettingAn academic medical center.PatientsSixty-two patients with a histological diagnosis of SESCC by routine endoscopy. In the phase I study, 35 images from 16 patients were used. In the phase II study, 109 images from 46 subsequent consecutive patients enrolled from January 2007 to May 2009 were used.InterventionsWe performed OCT for preoperative staging followed by endoscopic submucosal dissection or a surgical procedure and compared precisely the visualized OCT sites with the corresponding tissue sections.Main Outcome MeasurementsThe accuracy of OCT for the staging.ResultsThe overall accuracy rate was 92.7% (EP/LPM, 94.9%; MM, 85.0%; SM, 90.9%). The OCT signal penetration depth was sufficient to depict the boundary of the deepest region of cancer, the thickness of which was less than 1.5 mm.LimitationsThe small number of patients.ConclusionsTo our knowledge, this is the first study demonstrating that OCT might be useful for the preoperative staging of SESCCs with a high degree of accuracy.