Understanding the Molecular and Genetic Differences Between GCT at the Time of the Initial Diagnosis and at Late Relapse

This study will examine two cohorts:

1. The initial diagnosis only cohort will include 3 patients with GCT who meet the inclusion criteria and have adequate tissue samples available in storage at the Pathology Department. One prospective blood and one tissue sample will be collected from each patient in this cohort. Tissue samples will come from the orchiectomy or virgin retro-peritoneal lymph node dissection (RPLND) that was done at initial diagnosis.
2. The late relapse cohort will include 3 patients with late relapse GCT who meet the inclusion criteria and have adequate tissue samples available in storage at the Pathology Department. One prospective blood and two tissue samples will be collected from each patient in this cohort. Tissue samples will come from the orchiectomy or virgin RPLND that was done at initial diagnosis and the other will come from the site of late relapse.

Patients in this cohort will have biopsies at the site of late relapse as part of their routine cancer treatment. No biopsies will be performed specifically for the purposes of this study. Tissue from the site of late relapse will also be requested from the Pathology Department.

One tube of blood will be collected from each subject during a routine clinical visit at baseline when a blood draw is already being done.

In summary, a total of 15 samples will be evaluated on this study. Consent for the use of tissue and blood collected for the purposes of this study will be obtained prior to any study procedures. Subjects who do not have adequate tissue samples available will be replaced.