Prospective Phase I/II Study Evaluating the Safety and Efficacy of Preoperative Carbon Ion Radiotherapy in Patients With Soft Tissue Sarcoma : The SARCOMA-01 Trial by the Severance sARCOma Multidisciplinary Team

"This prospective, single-institution Phase I/II clinical trial investigates the safety, feasibility, and preliminary efficacy of preoperative carbon-ion radiotherapy (CIRT) for patients with resectable soft tissue sarcoma. Given the radioresistant nature of sarcomas and the limitations of photon-based preoperative radiotherapy-particularly high wound complication rates-CIRT is expected to enhance local tumor control while minimizing treatment-related toxicity and surgical morbidity. The trial consists of an initial dose-escalation phase (phase 1) to identify an optimal and tolerable dose level, followed by an expansion phase (phase 2) assessing the feasibility of completing both CIRT and surgery without major wound complications. CIRT is delivered in eight fractions over two weeks, with surgery planned 6-8 weeks after radiotherapy. Primary endpoints include the incidence of grade 3-5 post-operative wound complications within 120 days and overall treatment completion. Secondary endpoints include pathological response, surgical outcomes, local control, progression-free survival, overall survival, and patient-reported quality of life. All participants will be followed for at least 12 months postoperatively to evaluate safety and long-term outcomes.

Sex

All

Minimum age

19 Years

Inclusion Criteria:

* Adults aged 19 years or older.
* Histologically confirmed soft tissue sarcoma deemed suitable for curative resection.
* Determined by the Yonsei Cancer Center sarcoma multidisciplinary team that preoperative carbon-ion radiotherapy followed by surgery is appropriate, considering tumor histologic subtype, size, and location.
* Eastern Cooperative Oncology Group (ECOG) performance status 0-1 or Karnofsky Performance Status (KPS) ≥ 70.
* Adequate organ function (including hematologic, hepatic, and renal function) suitable for radiotherapy and surgery.
* Voluntarily provided written informed consent.

Exclusion Criteria:

* Presence of distant metastases.
* Inability to plan carbon-ion radiotherapy due to metallic implants or other factors at the tumor site.
* History of prior radiotherapy to the same anatomical region.
* Presence of other serious medical conditions or active infections that, in the investigator's judgment, could interfere with study participation.
* Presence of active implanted electronic devices (e.g., pacemaker or defibrillator) without established safety for carbon-ion radiotherapy.
* Pregnant or breastfeeding women.