Execution of mantle field with multileaf collimator: A simple approach

Background: Until very recently mantle field radiotherapy remained the gold standard for the treatment of favorable early-stage Hodgkins lymphoma. The classic mantle includes all the major lymph nodes above the diaphragm and extends from the inferior portion of the mandible to the level of the insertion of the diaphragm. Aims: To describe a simple technique that has been devised to treat the mantle field with the help of multileaf collimator and using computed tomography (CT)-based treatment planning. Materials and Methods: CT scan was performed with the patient in the supine position and the datasets were transferred to the Eclipse(TM) treatment planning system. Elekta Precise(TM) linear accelerator equipped with 40 pairs of multileaf collimator (MLC) was used for the execution of the mantle field. The MLCs shapes were designed to take the shape of the conventional customized blocks used for treatment of mantle field. The anterior mantle field was divided into three separate MLC segments with the collimator kept at 0. The first MLC segment was shaped to cover the neck, clavicular regions, and mediastinum. The second and the third MLC segments covered the right and left axilla, respectively. The posterior fields were opposed to the anterior subfields in a similar fashion. The dose was prescribed at the midplane, using reference points. Results and Conclusion: The technique described in this study is very simple, easy to implement, and avoids unnecessary delay in the execution of the mantle field. The mantle field can be easily shaped with the multileaf collimators, without any collimator rotation.