GEIS-21 protocol

The GEIS-21 protocol (also known as the modified P6 or mP6 regimen) is an intensive multi-agent chemotherapy treatment developed by the Grupo Español de Investigación en Sarcomas (GEIS) for children and young adults with newly diagnosed Ewing's sarcoma. This combination therapy is a modification of the Memorial Sloan Kettering Cancer Center (MSKCC) P6 protocol and typically includes cyclophosphamide, doxorubicin, vincristine, ifosfamide, and etoposide. For patients classified as high-risk—such as those with metastatic disease, axial-pelvic primary tumors, or bone marrow micrometastasis—the protocol incorporates a "window phase" and maintenance therapy consisting of gemcitabine and docetaxel. The regimen works through multiple mechanisms, including DNA alkylation, topoisomerase II inhibition, and microtubule disruption, to target rapidly proliferating malignant cells. It is evaluated as part of a multimodal approach involving surgery and radiotherapy.

Other names

modified P6 protocolGEIS-21 chemotherapyGEIS21 chemotherapyGEIS 21 chemotherapymP6 regimenmP-6 regimenmP 6 regimen