Benign Testicular Teratomas in Postpubertal Patients: A Clinical, Histopathologic, and Molecular Genetic Analysis of 24 Cases
Chen Zhang, Daniel M Berney, Michelle S Hirsch, Liang Cheng, Thomas M Ulbright. Indiana University School of Medicine, Indianapolis, IN; Queen Mary University of London, London, United Kingdom; Harvard Medical School, Boston, MA
Background: Benign postpubertal testicular teratomas, apart from rare dermoid cysts, are not widely recognized. We aimed to expand the reported experience with testicular dermoid cyst and also to bring to the attention of both pathologists and treating physicians a small subset of postpubertal teratomas that do not meet the criteria for dermoid cyst but that nonetheless have benign features and clinical outcomes.
Design: We collected 24 cases of benign postpubertal teratoma, including 10 dermoid cysts. H&E-stained sections of all were reviewed. Postpubertal status was based on active spermatogenesis in the testis. Inclusion required that the following features were absent: 1) intratubular germ cell neoplasia; 2) cytological atypia of the teratoma; 3) microlithiasis; and 4) more than focal tubular atrophy and sclerosis immediately adjacent to the teratoma. Patient demographic information and the gross findings were obtained from pathology reports. Follow-up was obtained from referring physicians. FISH for chromosome 12p abnormalities was performed on formalin-fixed, paraffin-embedded tissue.
Results: Patients ranged from 12-59 years old. In most cases, the tumor was cystic or partially cystic. On microscopic examination, the 10 dermoid cysts were lined by keratinizing, stratified squamous epithelium with associated pilosebaceous units and sweat glands in an organoid pattern. Squamous cysts also occurred in 9 of 14 non-dermoid teratomas, which, by definition, lacked adnexal structures. Apart from 2 dermoid cysts additional elements occurred in all cases, most commonly ciliated or respiratory-type epithelium (67%) and smooth muscle (67%). Organoid structures were present in 5 of the non-dermoid teratomas, usually glandular arrangements of ciliated epithelium, with or without goblet cells, encircled by thick bundles of smooth muscle with, in some cases, embedded seromucinous acini. FISH for chromosome 12p was performed in 17 cases, and none displayed an abnormal 12p. All 18 patients with follow-up information were alive at post-operative intervals of 5-168 months.
Conclusions: This study supports the recognition and separate classification of not only dermoid cysts but also a small subset of benign testicular teratomas in postpubertal patients that share many features with dermoid cysts but lack cutaneous-type adnexal structures.
Category: Genitourinary (including renal tumors)
Tuesday, March 5, 2013 9:30 AM
Poster Session III # 107, Tuesday Morning