Esophageal leukoplakia or epidermoid metaplasia: a clinicopathological study of 18 patients.

Oral leukoplakia is a relatively common, painless disorder of the oral mucosa. It predominantly affects middle-aged to elderly men and has a strong association with tobacco smoking and alcohol intake. Concomitant histological findings of hyperorthokeratosis and a well-developed granular cell layer, termed orthokeratotic dysplasia, are often associated with oral squamous cell carcinoma. In contrast, analogous lesions within the esophagus, termed esophageal epidermoid metaplasia, are rarely encountered and poorly described in the literature. To better characterize the clinicopathological features of this entity, we have collected 25 cases from 18 patients. Patients ranged in age from 37 to 81 years (mean, 61.5 years), with a slight female predominance (10/18, 56%). On presentation, a majority of patients complained of dysphagia (10/18, 56%). Past medical history was significant for tobacco smoking or long history of second-hand smoke in 11 (61%) patients and alcohol intake in 7 (39%) patients. Seventeen (94%) patients with esophageal epidermoid metaplasia were located within the middle-to-distal esophagus. Histologically, all cases were sharply demarcated and characterized by epithelial hyperplasia, a thickened basal layer, acanthotic midzone, a prominent granular cell layer, and superficial hyperorthokeratosis. Adjacent high-grade squamous dysplasia and/or squamous cell carcinoma were seen in 3 out of 18 (17%) patients. Follow-up information was available for 13 out of 18 (72%) patients and ranged from 2 to 8.3 years (mean, 2.3 years). Seven of the 13 (54%) patients had persistent disease; however, none of them developed squamous dysplasia or squamous cell carcinoma. In an effort to assess the incidence of esophageal epidermoid metaplasia, 198 consecutive esophageal biopsies were prospectively surveyed over a 6-month period at three academic institutions. No cases were identified within this time frame. In summary, esophageal epidermoid metaplasia is a rare condition affecting the middle-to-distal esophagus in middle-aged to elderly females. The occurrence of adjacent high-grade squamous dysplasia and/or squamous cell carcinoma warrants close follow-up.