Endoscopic Features of Superficial Esophageal Squamous Cell Carcinoma in Patients with Very Low Risk Factors (Female, Nondrinking, and Nonsmoking): A Case-Control Study.

BACKGROUND: Although esophageal squamous cell carcinoma (ESCC) is more likely to develop in patients with any risk factor (male, drinking, or smoking), it is sometimes detected in patients with very low risk factors (female, nondrinking, and nonsmoking). We examined the endoscopic features of superficial ESCC in patients with very low risk factors. METHODS: In this single-center case-control study, 666 patients with 666 superficial ESCC lesions were divided into 2 groups: those with very low risk factors (very low-risk group, n = 34) and those with any risk factors (any-risk group, n = 632). After case-control selection at a 1:5 ratio, the very low-risk group comprised 34 patients and the any-risk group comprised 170 patients. We compared the baseline characteristics, endoscopic findings, and treatment results (including pathological diagnosis) between the 2 groups. RESULTS: There were no statistically significant differences between the 2 groups in age, tumor size, tumor location, tumor morphology, or treatment results (including tumor depth and lymphovascular invasion). A longitudinal lesion with an attachment of white keratinized epithelium was more likely to be detected in the very low-risk group than the any-risk group (61.8 vs. 17.6%, respectively; p < 0.001). CONCLUSIONS: ESCC in patients with very low risk factors is rare but can be encountered in daily practice. A longitudinal lesion with an attachment of white keratinized epithelium is its main characteristic, which is slightly different from that of patients with any risk factors.