title: A highly reproducible bolus immobilization technique for the treatment of scalp malignancies.
abstract: Radiation treatment of scalp malignancies can be a challenge due to the multiple curved surfaces to which homogenous dose must be delivered. The most readily available techniques utilize linear accelerator-based technique of opposed lateral electron field abutting opposed lateral photon field with central blocking. Bolus material is used to achieve adequate skin dose. Although plans to add bolus material often occur in the virtual setting during treatment planning, the practical aspects of reproducibly maintain the bolus material along curved surfaces during the day-to-day patient setup can be a challenge. We present a case of a patient with squamous cell carcinoma of the scalp with neck node involvement treated with surgery followed by adjuvant radiotherapy. We demonstrate a unique immobilization technique that maintains the bolus material on the aquaplast mesh adherent to the patient's scalp as well as the neck. TomoTherapy with daily megavoltage computed tomography (CT) scan was utilized to verify the daily bolus position. We were able to maintain a 95% reproducibility rate. This technique reliably maintains the bolus material on the desired locations with minimum adjustments and manipulation by the therapist and is a technique that can be universally adaptable for conventional radiotherapy or intensity modulated radiation therapy (IMRT) techniques.
authors.affiliation: Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA.
authors.forename: Steven H
authors.initials: SH
authors.lastname: Lin
authors.forename: Diane
authors.initials: D
authors.lastname: Latronico
authors.forename: Terrance
authors.initials: T
authors.lastname: Teslow
authors.forename: Gopal K
authors.initials: GK
authors.lastname: Bajaj
mesh_terms: D002266:Carboxymethylcellulose Sodium; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007103:Immobilization / Q000295:instrumentation* / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D015203:Reproducibility of Results; D012535:Scalp / Q000528:radiation effects*; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000532:radiotherapy*
chemical_list: D002266:Carboxymethylcellulose Sodium