<unk> s constitute a vast majority of the incidences of testicular<unk> s.<unk> s are classified by their histology, regardless of location in the body. However, as more information about the genetics of these<unk> s become available, they may be classified based on specific gene mutations that characterize specific<unk> s. They are broadly divided in two classes: * The<unk> inomatous or seminomatous<unk> s (GGCT,<unk>  include only<unk> inoma and its synonyms dysgerminoma and seminoma. * The nongerminomatous or nonseminomatous<unk> s <unk> ,<unk>  include all other<unk> s, pure and mixed. The two classes reflect an important clinical difference. Compared to<unk> inomatous<unk> s, nongerminomatous<unk> s tend to grow faster, have an earlier mean age at time of diagnosis (around 25 years versus 35 years, in the case of testicular cancers), and have a lower five-year survival rate. The survival rate for<unk> inomatous<unk> s is higher in part because these<unk> s are very sensitive to radiation, and they also respond well to chemotherapy. The prognosis for nongerminomatous<unk> rs has improved dramatically, however, due to the use of platinum-based chemotherapy regimens.<unk> inomatous<unk>  ICD-O Peak Age (yr) Benign or malignant Histology<unk>  marker<unk> inoma (including dysgerminoma and seminoma) 40–50 Malignant Sheets of uniform polygonal cells with cleared cytoplasm; lymphocytes in the stroma About 10% have elevated hCG Dysgerminoma Seminoma Placental alkaline phosphate (PLAP) Nongerminomatous<unk>  ICD-O Peak Age (yr) Benign or malignant Histology<unk>  marker Embryonal carcinoma 9070/3 20–30 Malignant Poorly differentiated, pleomorphic cells in cords, sheets, or papillary formation secrete hCG, AFP Endodermal sinus<unk> , also known as yolk sac<unk>  (EST, YST) 9071/3 3 Malignant Poorly differentiated endothelium-like, cuboidal, or columnar cells 100% secrete AFP Choriocarcinoma 9100/3 20–30 Malignant Cytotrophoblast and syncytiotrophoblast without villus formation 100% secrete hCG Teratoma including mature teratoma, dermoid cyst, immature teratoma, teratoma with malignant transformation 9080/0-9080/3 0–3, 15–30 Mature teratoma, dermoid cyst usually benign (but follow-up required); others usually malignant Very variable, but "normal" tissues are common Pure<unk> s do not secrete hCG, AFP Polyembryoma 9072/3 15–25 ? ? ? Gonadoblastoma 9073/1 ? ? ? ? Mixed<unk>  ICD-O Peak Age (yr) Benign or malignant Histology<unk>  marker Mixed 15–30 Malignant Depends on elements present Depends on elements present Mixed<unk> s occur in many forms. Among these, a common form is teratoma with endodermal sinus<unk> . Teratocarcinoma refers to a<unk>  that is a mixture of teratoma with embryonal carcinoma, or with choriocarcinoma, or with both. This kind of mixed<unk>  may be known simply as a teratoma with elements of embryonal carcinoma or choriocarcinoma, or simply by ignoring the teratoma component and referring only to its malignant component: embryonal carcinoma and/or choriocarcinoma. They can present in the anterior mediastinum.
Germ cell tumor
Gonadoblastoma
Brown tumor
Ovarian germ cell tumors
Embryoma
Granulosa cell tumour
Neuroma
Endolymphatic sac tumor