Supplementary Material for: Unresectable Desmoplastic Small Round Cell Tumor: A Case Report and Review of the Literature

Introduction: Desmoplastic Small Round Cell Tumor (DSRCT) is a highly aggressive and rare soft tissue sarcoma that primarily affects young males and typically presents with disseminated abdominopelvic disease. The chromosomal translocation t(11;22)(p13;q12), which generates the EWSR1:WT1 fusion gene, is the defining genetic hallmark that distinguishes DSRCT from other small round cell sarcomas. Case Presentation: We report the case of a 38-year-old male with unresectable intra-abdominal DSRCT treated with the VAC-IE regimen (vincristine, doxorubicin, and cyclophosphamide, alternating with ifosfamide and etoposide) as first-line therapy. He achieved stable disease as the best response, with a progression-free survival of five months. As second-line therapy, he received gemcitabine and docetaxel. Discussion: Current therapeutic strategies are based on a multimodal approach including cytoreductive surgery, intensive chemotherapy, and postoperative abdominopelvic radiotherapy. The VAC-IE regimen remains the most widely used in both neoadjuvant and first-line settings. Alternative regimens include temozolomide plus irinotecan, or gemcitabine plus doxorubicin. In patients with androgen receptor positivity, hormonal blockade with leuprolide and bicalutamide may be a therapeutic option, particularly in frail patients. Recent studies also suggest potential roles for targeted therapies including PARP inhibitors, CDK4/6 inhibitors, and HER2-directed antibody-drug conjugates based on molecular profiling. Conclusion: DSRCT is a challenging and aggressive malignancy requiring a multidisciplinary and individualized approach. The combination of systemic therapy and local control measures remains critical for improving patient outcomes.