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Purpose To evaluate, in a prospective study, the use of 111 In–capromab pendetide (ProstaScint) scan to guide the delivery of a concomitant boost to intraprostatic region showing increased uptake while treating the entire gland with intensity-modulated radiotherapy for localized prostate cancer. Methods and Materials From September 2002 to November 2005, 71 patients were enrolled. Planning pelvic CT and 111 In–capromab pendetide scan images were coregistered. The entire prostate gland received 75.6 Gy/42 fractions, whereas areas of increased uptake in 111 In–capromab pendetide scan received 82 Gy. For patients with T3/T4 disease, or Gleason score ≥8, or prostate-specific antigen level >20 ng/mL, 12 months of adjuvant androgen deprivation therapy was given. In January 2005 the protocol was modified to give 6 months of androgen deprivation therapy to patients with a prostate-specific antigen level of 10–20 ng/mL or Gleason 7 disease. Results Thirty-one patients had low-risk, 30 had intermediate-risk, and 10 had high-risk disease. With a median follow-up of 66 months, the 5-year biochemical control rates were 94% for the entire cohort and 97%, 93%, and 90% for low-, intermediate-, and high-risk groups, respectively. Maximum acute and late urinary toxicities were Grade 2 for 38 patients (54%) and 28 patients (39%) and Grade 3 for 1 and 3 patients (4%), respectively. One patient had Grade 4 hematuria. Maximum acute and late gastrointestinal toxicities were Grade 2 for 32 patients (45%) and 15 patients (21%), respectively. Most of the side effects improved with longer follow-up. Conclusion Concomitant boost to areas showing increased uptake in 111 In–capromab pendetide scan to 82 Gy using intensity-modulated radiotherapy while the entire prostate received 75.6 Gy was feasible and tolerable, with 94% biochemical control rate at 5 years.

Purpose: To design an afterloading vaginal cylinder application appropriate to treat the vault with high dose rate (HDR) brachytherapy after prior total abdominal hysterectomy. Methods and Materials: A vaginal cylinder was designed and built using nylon and source loading channels positioned for source movement for HDR vault and vaginal brachytherapy. The channels are positioned to treat a broader isodose surface and to avoid the "end" effects of linear source brachytherapy. The central channel allows an applicator tube to be advanced beyond the end of the cylinder to treat a "tented" vault or a cervical stump (or uterus). Additional peripheral sources can be added to allow vaginal wall plaque therapy. Results: The application allows vault, vault plus proximal vagina, or vault plus entire vagina therapy using HDR. The isodose surface treated is controlled by source positioning and dwell times. Conclusion: The HDR cylinder has wide potential usability for uterus or cervix therapy as both low stage and operable endometrial carcinomas are now usually treated by surgery.

Purpose : A basis is presented for predicting the reduction in radiation dose to the larynx attributable to swallowing during radiation therapy treatment. Methods and Materials : Laryngeal movement associated with swallowing can occur during radiation therapy even when the patient's head is immobilized. Data on the extent and timing of laryngeal motions and the frequency of swallowing were used to predict the effect such motion would have on accuracy of radiation dose to the larynx. Results : In a nontrachestomized adult the larynx elevates approximately 2 cm during a swallow and moves anteriorly less than 1 cm. The normal frequency of swallowing in the supine position is once every 1–2 min. During therapy, the likelihood of a swallow occurring during an irradiation interval depended on the duration of the interval. For irradiation intervals less than 2 min long the ratio of number of swallows to number of intervals was 0.27. For irradiation intervals between 2–3 min long the ratio was 1.76. Based on conservative estimates of radiation field dimensions, larynx motion, and incidence of swallowing, the reduction in radiation dose attributable to swallowing during treatment would be approximately 0.5%. Conclusion : With small fields the total dose is only decreased by 0.5% with swallowing, so the change in the total dose is insignificant.