Abstract: PD53-06
Sources of Funding: none

Introduction

The overall survival for men diagnosed with pure seminoma is excellent. We sought to detail the retroperitoneal pathologic findings and treatment of men with pure seminoma who experienced a late relapse after their initial therapy.

Methods

The Indiana University Testis Cancer Database was queried for patients with a diagnosis of pure seminoma from 1987 to 2016. Patients with a late relapse who underwent a retroperitoneal lymph node dissection (RPLND) were included. Late relapse was defined as the dates between orchiectomy and RPLND being > 3years. This timeframe was used to account for treatment in the initial year for those who presented with metastatic disease. Patient charts were reviewed to identify patient demographics, tumor, and treatment characteristics. Categorical variables were assessed using Fisher’s exact test.

Results

A total of 16 patients met inclusion criteria. Twelve patients initially presented with clinical stage I disease. Of these, 6 (50%) were treated with adjuvant radiotherapy, 5 (42%) were managed with surveillance, and 1 (8%) received 2 cycles of adjuvant carboplatin. The remaining 4 patients initially presented with metastatic disease and were treated with combination platinum-based chemotherapy. The median time between radical orchiectomy and RPLND was 64 months (range 32-415). The location of recurrent disease was the retroperitoneum in 14 patients (88%) and the pelvis in 2 patients (12%). Recurrent seminoma was identified at the time of RPLND in 5 patients (31%). Three patients (19%) had necrosis only. The remaining 8 (50%) patients were found to nonseminomatous components in the retroperitoneal specimen. Of the 6 patients with clinical stage I initially treated with radiotherapy, 1 patient had recurrent seminoma, 1 was found to have a Leydig cell tumor, 2 patients demonstrated a malignant transformation to sarcoma and rhadomyosarcoma, and 2 were found to have nonseminoma. Patients initially treated with radiotherapy for clinical stage I disease required more induction and salvage chemotherapy as well as more additional procedures (i.e. nephrectomy, bowel resection, etc) at the time of RPLND (66% vs. 33%, p=0.09).

Conclusions

Patients who received radiotherapy for clinical stage I disease have an unpredictable retroperitoneal histology and require a higher burden of treatment at the time of relapse compared to those without radiotherapy. Overall, 50% of patients were found to have malignant transformation or nonseminoma at the time of late relapse.

Funding

none