Lobular endocervical glandular hyperplasia is a metaplastic process with a pyloric gland phenotype

Lobular endocervical glandular hyperplasia of the uterine cervix is a rare pseudoneoplastic lesion of the uterine cervix, described recently. Our aim was to characterize the clinicopathological and immunohistochemical features of lobular endocervical glandular hyperplasia, to elucidate its pyloric gland phenotype, and to distinguish it from adenoma malignum of the uterine cervix.

Nine cases of lobular endocervical glandular hyperplasia were studied histologically and immunohistochemically. The average age of the nine patients was 48.8 years (range 38-64 years). Six cases were found incidentally, whereas in three cases a watery vaginal discharge and imaging studies suggested adenoma malignum preoperatively. Microscopically, lobular endocervical glandular hyperplasia ranged from 1 mm to 20 mm (mean 6.8 mm) in the largest horizontal extent and 1 mm to 10 mm (mean 3.9 mm) in depth, and was characterized by lobular arrangements of small glands composed of low columnar cells with pale eosinophilic cytoplasm and bland nuclei. Three cases showed a pseudo-invasive growth. Intracytoplasmic mucin was predominantly PAS-positive, and seven cases showed immunoreactivity for M-GGMC-1, an antibody that reacts with pyloric gland-type mucin. Only focal and faint reactivity for CEA was seen, and ER was negative in all cases. The cytokeratin profile was CK7+/20- in all cases, in keeping with their Müllerian derivation. All three lesions examined contained chromogranin-positive endocrine cells. After surgery all patients are well without recurrent disease (mean follow-up was 48.4 months).

Lobular endocervical glandular hyperplasia is a morphologically distinct pseudoneoplastic glandular lesion, which has unique phenotypic characteristics shared by pyloric glands of the stomach. Although most are found incidentally, some cases may show clinical and radiological features resembling those of adenoma malignum.