# An Uncommon Presentation of Growing Teratoma Syndrome in a Patient Treated for Testicular Immature Teratoma: A Case Report

## TL;DR

A patient with testicular cancer developed a rare condition called Growing Teratoma Syndrome after chemotherapy, highlighting the need for careful monitoring and multidisciplinary care.

## Contribution

This case report adds to the limited literature on Growing Teratoma Syndrome following immature teratoma treatment.

## Key findings

- A patient with immature teratoma developed enlarging lymph node masses post-chemotherapy, confirmed as mature teratoma.
- Systemic therapy was ineffective, and surgical excision was the primary treatment approach.
- The case emphasizes the importance of multidisciplinary follow-up for timely diagnosis and management of GTS.

## Abstract

Growing teratoma syndrome (GTS) is an uncommon post-chemotherapy event in non-seminomatous germ cell tumors and presents as enlarging masses composed of mature teratoma despite normalized markers. As systemic therapy is generally ineffective, treatment focuses on surgical excision. We report the case of a 30-year-old male with an immature teratoma of the right testis who, after completing chemotherapy with normalized tumor markers, developed enlarging lymph node masses histologically confirmed as mature teratoma, consistent with GTS. This case highlights the importance of maintaining a high index of suspicion for GTS in patients with immature teratomas undergoing chemotherapy and underscores the critical role of multidisciplinary follow-up to ensure timely diagnosis and effective management.