[Clinicopathological features of verrucous type dysplasia of esophagus]

Objective: To investigate the clinicopathological features of verrucous type (squamous) dysplasia of esophagus. Methods: The clinicopathological data of 18 verrucous type dysplasia of esophagus patients in the 989th Hospital of the Joint Logistics Support Force of the People's Liberation Army (formerly 152 Central Hospital) and Beijing Chaoyang Hospital Affiliated to Capital Medical University from 2009 to 2021 were retrospectively collected. The histomorphologic characteristics and immunophenotype were observed, and human papillomavirus (HPV) genotyping was detected by PCR-fluorescence probe. The relevant literature was reviewed. Results: The median age of the 18 patients was 68 years (range 53-76 years); there were 13 males and 5 females. There were four cases in the upper esophagus, seven in the middle esophagus and seven in the lower esophagus. The median diameter of the lesion was 18 mm (range 6-54 mm). According to the Paris Classification, 11 cases were 0-Ⅱa, one case was 0-Ⅱa+Ⅰ, five cases were 0-Ⅱb, and one case was 0-Ⅱb+Ⅰ. White light endoscopy showed that the surface of the lesion was white plaque, red areas between the plaques, and papillary surface structure could be seen. In narrow-band imaging, some mucosal areas of lesions were opaque or patchy and light brown, and papillary microsurface structures were different in shapes and sizes. Intraepithelial microvessels were elongated, dilated, twisted and varied in diameter. Lugol iodine stain showed nil to faint staining. Histologically, the atypia cells were large with rounded to irregular nuclei, coarse chromatin, mitotic figures, and abundant eosinophilic cytoplasm. The basal cells showed increased atypia, crowding, increased nuclear-cytoplasmic ratio, and active mitosis. The cells were arranged haphazardly. Single cell keratinization, binuclear cells, and hollow-out-like cells, as well as surface epithelial keratinization and parakeratosis were observed in three cases. There were obvious verrucous or papillary structures in the epithelial layer. Five patients had local verrucous carcinoma. Immunohistochemical staining showed that the mutant expression of p53 protein in 6/10 cases; p16 was positive in 5/10 cases; abnormal Ki-67 distribution pattern in 10/10 cases. HPV was negative in all 10 cases tested. The original pathologic diagnosis of preoperative biopsy was high-grade dysplasia in 8 cases, low-grade dysplasia in 6 cases and atypical squamous epithelial cells in 4 cases. Conclusions: Esophageal verrucous dysplasia tumor cells are well differentiated with obvious verrucous or papillary structures. The unique morphological features suggest that it represents a histological subtype of esophageal squamous high-grade dysplasia and it is a precursor of verrucous carcinoma. Its preoperative biopsy diagnosis is challenging.