Mixed germ cell tumors: Experience of a single institution over past 15 Years

ABSTRACT

Malignant mixed germ cell tumors [MMGCT] are rare ,biologically diversified and diagnostically challenging tumors. They arise in the gonads more frequently than at extragonadal sites and their individual constituents are the same in both gonads .In the testis they account for 40-45% of all primary testicular tumors .In the ovary an incidence between 12% to 28% is reported in literature. Extragonadal GCT [germ cell tumors] constitute nearly 3% of pediatric brain tumors and Germinomas alone account for approximately two thirds, of all GCT . Aim: The purpose of this retrospective study was to present the clinicopathological profile of these rare, less well studied and intriguing malignant mixed germ cell tumors [MMGCTs] in both genders and inclusive of gonadal and extra gonadal locations. All primitive germ cell tumors inclusive of both genders and all sites were retrieved from the archives of the Anatomical Pathology Department at King AbdulAziz University Hospital,Jeddah between 1995-2010 through a computerized search. A total of 28 primitive GCTs were retrieved in both genders and in all locations. Nineteen [67.85%] of the tumors were pure germ cell type. MMGCTs were 9 [32.14%] of all primitive GCTs with a mean age of 21.22 years. Of the 9 MMGCTs in both genders that were studied further 7[25%] were gonadal and 2[7.14%] were extra-gonadal [intracranial] in location . Five [17.85%] were testicular MMGCTs with a mean age of 23.6 years. Two [7.14%] were ovarian MMGCTs with a mean age of 27 years. Two [7.14%] cases were extragonadal [intracranial] in location and both the patients were pediatric males with a mean age of 9.5 years. Clinical, radiological, demographic origin, pathological characteristics and immunohistochemical profile of all MMGCTs are presented along with review of literature. Malignant germ cell tumors are rare and our findings suggest that MMGCTs in general have a favourable prognosis regardless of histological constituents or location and despite a higher clinical stage