testicular cancer a malignant spermatocytic seminoma computer illustration and light micrograph a seminoma is a malignant tumour cancer of the testis testicle although this is a rare cancer it is the most common cancer in 15 to 35 year old men it arises from abnormal germ cells precursors to sperm cells in the seminiferous tubules surgical removal of the affected testis orchidectomy is followed by radiotherapy and chemotherapy if required 2c4g090.jpg from ≡mypornvid fck cancer View Photo