296. CLINICAL T1B-SM2-3N0M0 ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Background With advancements in endoscopic techniques, safer and more reliable endoscopic resection of submucosal invasive lesions has become feasible. The evaluation of treatment outcomes for superficial esophageal carcinoma has typically been predicated on the depth of pathological diagnosis; however, there have been limited studies based on preoperative diagnosis. Given that treatment decisions in clinical practice are primarily guided by preoperative diagnosis, there is a heightened emphasis on studies grounded in preoperative assessments. This study aims to analyze the accuracy of preoperative diagnosis of T1b-SM2-3 N0M0, evaluate the accuracy of treatment selection and depth diagnosis, and assess long-term outcomes based on these determinations. Methods Thirty-eight patients diagnosed with T1b-SM2-3 N0M0 between April 2010 and December 2020 were included in the study. Depth diagnosis was determined through endoscopic evaluation utilizing white light, NBI, NBI magnification plus EUS, with lymph node metastasis diagnosis performed via CT imaging. Treatment decisions were made following patient consent, and long-term prognosis was assessed for each treatment modality. Results Initial treatment involved ESD in 14 patients, with an additional 5 patients undergoing additional treatment (ESD + AD) based on histological evaluation (surgery: 1, CRT: 4). Surgery or neoadjuvant chemotherapy (NAC) followed by surgery was performed in 15 patients, with CRT administered in 7. Among the 22 patients who did not receive NAC and whose histologic depth was evaluable, the accuracy rate of depth diagnosis was 64%, primarily attributable to overdiagnosis. In the 14 patients who underwent ESD excluding piecemeal resection, the negative rate of vertical margins was 93%. Five-year overall survival rates were as follows: ESD: 64.8%, ESD+AD: 75%, surgery: 86.2%, and CRT: 45.7%, with no statistically significant differences observed. The majority of deaths (83%) were attributed to other diseases or cancers, with only 2 deaths attributed to the primary disease. Conclusion ESD or surgery emerged as the preferred treatment modalities in the majority of cases, with relatively favorable long-term prognoses. Treatment decisions were influenced by comorbidities and other factors, potentially impacting long-term outcomes.