title: Spinal cord dose reduction using an anterior 13 MeV electron field situated between a split anterior 60Co supraclavicular field.
abstract: As part of the treatment for lymphoma, disease involving the supraclavicular region has been treated with megavoltage 60Co photons to a midline dose of 30 to 45 Gy through an anterior involved field and a supplementary posterior field when necessary. The spinal cord was shielded with a 5 cm lead block during treatment to the posterior field. A typical 40 Gy treatment results in a dose to the lower cervical and upper thoracic spinal cord in the range of 22 to 26 Gy, a level that could compromise subsequent mediastinal treatment in the event of a relapse. To reduce this cord dose, the midportion of the anterior supraclavicular 60Co To reduce this cord dose, the midportion of the anterior supraclavicular 60Co field was replaced with a high-energy (13 MeV) electron port, which reduces the dose to the cord to below 6 Gy in the average adult patient. This modification of the routine supraclavicular treatment allows greater flexibility in future treatment in the event of a mediastinal relapse.
mesh_terms: D002968:Clavicle; D003037:Cobalt Radioisotopes / Q000627:therapeutic use; D004583:Electrons; D006801:Humans; D008223:Lymphoma / Q000532:radiotherapy*; D011835:Radiation Protection / Q000379:methods*; D011882:Radiotherapy, High-Energy / Q000379:methods*; D013116:Spinal Cord
chemical_list: D003037:Cobalt Radioisotopes