Crosscut and Covey-Tunnel Clusters-Uterine Cervix

Abstract

Tunnel clusters of uterine cervix articulate as a subtype of nabothian cyst delineating spherical aggregates of twenty to fifty intensely adherent tubules. Characteristically, lesion demonstrates a complex configuration of endocervical glands with multicystic dilatation. Subcategorized as type A and type B variants, type A tunnel clusters are constituted of miniature, non cystic endocervical glands whereas type B tunnel clusters exemplify cystic dilatation of endocervical glands. Of obscure aetiology, tunnel clusters are posited to represent a sub-involution within foci of endocervical glandular hyperplasia. Tunnel clusters are asymptomatic or may be associated with mucoid vaginal discharge. Type A tunnel clusters are composed of miniature, elongated, non-cystic endocervical glands layered with columnar to low cuboidal epithelium with mucinous cytoplasm, apical vacuoles and basal nuclei. Type B tunnel clusters are comprised of cystically dilated endocervical glands layered with bland, cuboidal or flattened epithelium and permeated with inspissated mucin. Tunnel clusters appear immune reactive to PAX2 wherein type A tunnel clusters with gastric metaplasia appear immune reactive to HIK1083. Tunnel clusters of uterine cervix require segregation from neoplasms such as minimal deviation adenocarcinoma or adenoma malignum, conventional endocervical adenocarcinoma, adenocarcinoma in situ, nabothian cysts and mesonephric remnants or mesonephric hyperplasia of uterine cervix. Tunnel clusters may be appropriately discerned with cogent histological examination of surgical tissue specimens of uterine cervix, appear devoid of precise, applicable therapeutic strategies and do not necessitate alleviation.