<prompt> The commonest histological type of carcinoma testis is -TeratomaYolk sac turomSeminomaChorio carcinoma  <response>: Tumors of the testis are a heterogeneous group of neoplasms that include germ cell tumors and sex cord stromal tumors. In postpubeal males, 95 of testicular tumors arise from germ cells, and all are malignant Seminomas are the most common type of germ cell tumor 50 of germ cell tumors. robbins book of pathology 9th edition page 659 Most common tumor of the testis: Seminoma Mixed germ cell tumor Most common testicular tumor in infant and children up to 3 years: Yolk sac tumor Most common testicular tumor in prepubeal children: Teratoma Most common testicular tumor 60 years: Lymphoma Most common bilateral tumor Primary is seminoma Secondary is lymphoma 