Patients with clinical stage I testicular
seminoma usually receive elective para-aortic lymph node radiation after
orchiectomy, which is effective in controlling subclinical microscopic disease. However, the majority of patients with clinical stage I
seminoma do not harbor occult
metastases and, therefore, do not require elective nodal treatment. Vascular space invasion by the primary testis
tumor recently has been shown to be an important predictor of
metastases in nonseminomatous
tumors but no such information exists to date in pure
seminoma. Therefore, patients with clinical stage I testicular
seminoma were compared to clinical stage II to IV
cancer patients with respect to the presence of several features of the primary
tumor. Vascular space invasion was identified significantly less frequently in stage I
cancer patients (17%, 5 of 29) than in those with stage II or greater disease (39%, 11 of 28, p equals 0.03, 1-tailed t test). Microscopic invasion of the tunica and rete testis, and
necrosis also were identified slightly more frequently in the higher stage
cancer patients. Of the 12 patients with a maximum
tumor dimension of more than 6 cm. 9 (75%) were in the stage II or higher group. Patient age, symptom duration and presenting complaint were similar in the 2 groups. Many higher stage
cancer patients did not exhibit aggressive histological characteristics and, therefore, the absence of these features cannot be used to select patients for surveillance. On the other hand, patients with clinical stage I
tumors that exhibit vascular space invasion may have an increased rate of occult para-aortic
lymph node metastases. Therefore, the presence of vascular space invasion may be a useful criterion for exclusion of patients from surveillance protocols. Confirmatory data are needed before a final recommendation can be made.