Microinvasive germ cell tumor of the testis

Abstract

Microinvasive germ cell tumor (MGCT) consists of a limited number of malignant germ cells in the intertubular tissue of the testis. The cells have large nuclei, prominent nucleoli, abundant clear cytoplasm, and distinct cellular borders in hematoxylin and eosin staining. MGCT can be the first stage of malignancy in the development of testicular germ cell tumor (TGCT). Biopsies from men with maldescended testes have been reported to contain intratubular germ cell neoplasia, unclassified (IGCN) and MGCT in 1.8% of the examined cases (95% CI 0.5-4.6%). MGCT has also been found in testes of subfertile men and in the contralateral testis of patients with TGCT. MGCT is a frequent finding (19%) in the testicular tissue adjacent to an overt TGCT. Men with a high risk of TGCT may gain from screening for precursor lesions of TGCT with ultrasonography of the testes followed by a testicular biopsy if suspicious abnormalities are found: Treatment is high-voltage radiotherapy for intratubular germ cell neoplasia (IGCN), and orchidectomy for MGCT and germ cell tumor in situ, either intratubular seminoma or intratubular embryonal carcinoma. After local treatment, patients with precursor lesions can be followed with a surveillance program. The mRNA levels of invasion-related genes were evaluated based on a DNA microarray data set, and we found two gene abnormalities most relevant for the invasion of malignant germ cells: matrix metalloproteinase 9 (MMP9) and plasminogen activator, urokinase (PLAU) genes were up-regulated in a study comparing tissue samples of TGCT and IGCN.

Precursor lesions in testis and dysgenetic gonads

“…In a recent review and in an original contribution [4,5], we argued against the present inconsistent usage of nomenclature for MGCT. The inconsistencies may detract from recognizing MGCT as a frequent and distinct pathologic entity between intratubular germ cell neoplasia/carcinoma in situ and gonadoblastoma as the initial neoplastic precursor lesions and macroscopically overt germ cell tumors.…”

“…Microinvasive germ cell tumor is an extratubular invasion of single malignant germ cells or small clusters of such cells in the testis that do not eradicate the tubular structures [3][4][5]. Furthermore, MGCT does not form a macroscopic mass and is not grossly visible.…”

Deregulation of Aurora kinase gene expression in human testicular germ cell tumours

“…The term 'germ cell tumours' refers to a heterogeneous group of neoplasms originating from cells belonging to the germ cell lineage (Looijenga & Oosterhuis, 1999;Lutke Holzik et al, 2004;Oosterhuis & Looijenga, 2005;von Eyben et al, 2005;Horwich et al, 2006). They occur mainly in the gonad, but also in specific extragonadal sites along the migration route of primordial germ cells.…”

Inhibition of the aurora kinases suppresses in vitro NT2-D1 cell growth and tumorigenicity

“…The term 'germ cell tumors' refers to neoplasms originating from cells belonging to the germ cell lineage and have three main profiles characterized by different epidemiological, histological, and clinical parameters (Looijenga & Oosterhuis 1999, Lutke Holzik et al 2004, von Eyben et al 2005, Oosterhuis & Looijenga 2005, Horwich et al 2006. They include teratomas-yolk sac tumors usually occurring over the early years of life, testicular germ cell tumors (TGCTs) forming after puberty and during adult life, and spermatocytic seminomas occurring in elderly men (von Eyben et al 2005, Oosterhuis & Looijenga 2005, Horwich et al 2006.…”

“…They include teratomas-yolk sac tumors usually occurring over the early years of life, testicular germ cell tumors (TGCTs) forming after puberty and during adult life, and spermatocytic seminomas occurring in elderly men (von Eyben et al 2005, Oosterhuis & Looijenga 2005, Horwich et al 2006. Overt TGCT is thought to develop from a precursor neoplastic lesion defined as intratubular germ cell neoplasia (IGCN) and represents the most common malignancy in young adult Caucasian males (Looijenga & Oosterhuis 1999, Bray et al 2006, Sokoloff et al 2007.…”