<prompt> All of the following clinicopathologic features are seen more often in seminomas as compared to non-seminomatous germ cell tumors of the testis except:Tumors remain localized to testis for a long timeThey are radiosensitiveThey metastasize predominantly by lymphaticsThey are often associated with raised levels of serum AFP and HCG  <response>: While hCG concentration may be inceased in patients with either nonseminoma or seminoma histology, the AFP concentration is increased only in patietns with nonseminoma. - HarrisonSeminomas represent about 50 of all Germ cell tumors of testis.Median age is 4th decade Nonseminomas are most frequent in the 3rd decade.Seminomas follow a more indolent course.Most seminomas 70 present with stage I disease disease limited to testis,about 20 with stage II disease with retroperitoneal metastases,and 10 with stage III disease spread beyond retroperitoneumSeminomas as well as non-seminomas typically metastasize through lymphatics except Choriocarcinoma which demonstrates early hematogenous spreadSeminomas are one of the most radiosensitive tumors Non seminomas are insensitive to radiation. 