3D conformational interstitial brachytherapy planning for soft tissue sarcoma

摘要

Soft tissue sarcomas (STS) are malignant tumours that originate in the bodysoft tissues including muscles. STS are very rare, but very serious, especially ifdiagnosed when the disease is advanced [4]. High-dose rate brachytherapy (HDR BT)for STS is often used followed by surgery to help eradication of any cancerous cellsthat remains after this procedure. With HDR BT radiation is deposited inside thebody, in the area of the tumour, thereby delivering a maximum dose while minimizingexposure of the surrounding healthy tissue. In this paper we present our earlyexperience in 3D conformational interstitial brachytherapy planning withBrachyVision v.11 (Varian software) for a forearm STS. The procedure wasperformed in a team, involving the effort of the surgeon, radiation oncologist,pathologist, medical physicist, and radiation therapy technician. The case was asingle-plan implant of 4 catheters, placed parallel to the incision. 3D treatmentplanning required computed tomography after recovery from surgery procedure. Theclinical target volume (CTV) was defined as the volume of tissue with risk ofmicroscopic spread, and includes the preoperative image tumour (visualized by CT " MRI fusion). Source loading was performed 7 days after catheters implant and woundclosure (single 192Ir source, GammaMed Plus iX afterloader equipment), then 3 Gywere delivered twice daily, during 5 days. We also, followed the patient response toHDR BT treatment. Concerning treatment-related complications [5], at the firstmedical examination after the treatment, the patient had no problem moving thefingers. However, the forearm revealed hematoma, but no infection or seroma.