We reviewed 40 patients with pure seminoma, paying particular attention to extratesticular and anaplastic seminomas, which have poor prognoses. In our study, two of the three patients with extratesticular seminoma had anaplastic histology; this association has not been stressed previously. We recommended that extratesticular seminoma, particularly with anaplastic histology, be considered for regional radiotherapy combined with chemotherapy. Bone scan should be part of the initial work-up of patients with extratesticular seminoma. Our review showed a low incidence of lymphatic and/or vascular invasion in typical as well as anaplastic seminoma. This could be because we did not interpret floating tumor cells in a vessel as indicative of vessel invasion.