A technique for postoperative irradiation of carcinomas of the larynx and hypopharynx.
Postoperative radiation is commonly employed for advanced lesions of the larynx and hypopharynx which have undergone a laryngectomy. It is technically difficult to achieve a homogeneous distribution of irradiation throughout the treatment volume because of the marked variation in contour across the treated area. We have described a technique which employs a 15 degrees lateral kick-out of the treatment table and a 15 degrees gantry angle above the horizontal for each of two lateral fields. This technique has certain advantages over other techniques previously described in the literature. By adding a gantry angle of 15 degrees above the horizontal to the kick-out lateral position of the table, we have found that we were able to decrease the amount of irradiation to the shoulder, to improve the dose to the posterior superior mediastinum, to lower the applied dose, and to avoid a hot spot overlying the spinal cord in the superior posterior portion of the field. This technique is particularly useful in patients who lack the flexibility to move their shoulders posteriorly and inferiorly.
Amos
E H
EH
West Florida Cancer Institute, Pensacola 32514.
Edwards
T
T
Lowrey
G C
GC
McCabe
M
M
D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy* / Q000601:surgery; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D007822:Laryngeal Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D007825:Laryngectomy; D011182:Postoperative Care; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy / Q000379:methods*