# A Case Study of a Rare Undifferentiated Spindle Cell Sarcoma of the Penis: Establishment and Characterization of Patient-Derived Models

## TL;DR

This paper describes the creation of patient-derived models for a rare penile sarcoma to better understand its biology and explore treatment options.

## Contribution

The establishment and characterization of multiple patient-derived models for a rare undifferentiated spindle cell sarcoma of the penis.

## Key findings

- Patient-derived models replicated key molecular traits like smooth muscle actin and CD99 expression.
- Mutations in TSC2 and FGFR4 genes were identified in the tumor models.
- The models offer potential for exploring the tumor’s biology and developing therapies.

## Abstract

Rare sarcomas present significant treatment challenges compared to more prevalent soft tissue sarcomas due to limited treatment options and a poor understanding of their biology. This study investigates a unique case of penile sarcoma, providing a comprehensive morphological and molecular analysis. Through the creation of experimental patient-derived models—including patient-derived xenograft (PDX), 3D, and monolayer primary cultures—we successfully replicated crucial molecular traits observed in the patient’s tumor, such as smooth muscle actin and CD99 expression, along with specific mutations in genes like TSC2 and FGFR4. These models are helpful in assessing the potential for an in-depth exploration of this tumor’s biology. This comprehensive approach holds promise in identifying potential therapeutic avenues for managing this exceedingly rare soft tissue sarcoma.