An evaluation of our experience in position verification of catheters used for interstitial high-dose-rate brachytherapy of solitary bladder tumors.

PURPOSE: The goal of this study was to verify the position of catheters used over 4 days for brachytherapy of solitary bladder tumors. METHODS AND MATERIALS: The study covered three phases. Shifting of catheters was studied using daily position verification CT scans of 20 patients. The possibility to omit the CT scan on Day 2 by adding a loading margin of 4 mm on each side was studied using data of 5 patients. Whether the Day 4 verification CT scan could be omitted if this margin was used, was studied for another group of 10 patients, comparing the Day 3 treatment plan to the Day 4 CT scan. RESULTS: An average catheter shift on Days 2, 3, and 4 of, respectively, -0.3 mm (-8 to 10 mm), -0.5 mm (-14 to 10 mm), and -0.1 mm (-16 to 28 mm) was found over the measurements at both sites of the catheter. Including only shifts causing underdosing of the clinical target volume (CTV), the average shift on Days 2, 3, and 4 was, respectively, -3.6 mm (-1 to -8 mm), -5.4 mm (-1 to -14 mm), and -5.3 mm (-1 to -16 mm). After adding a loading margin, the CTV was covered on Day 2; however, the margin was not sufficient for Days 3 and 4. On Day 4, in 2/10 patients, the CTV was not completely covered. In 5/10 patients, an increased 200% isodose volume was found. CONCLUSIONS: Position verification is necessary in bladder brachytherapy. If a 4-mm margin on each side of the loading pattern was added, position verification on Day 2 could be omitted. The verification CT scan of Days 3 and 4 is still necessary.

A prospective quality of life study in patients with locally advanced prostate cancer, treated with radiotherapy with or without regional or interstitial hyperthermia.

INTRODUCTION: The aim of this prospective study was to describe quality of life (QoL) in patients with locally advanced prostate carcinoma treated with conventional radiotherapy and to evaluate the influence of adding regional or interstitial hyperthermia. MATERIALS AND METHODS: All patients were irradiated using a CT-planned conventional three field technique, administering 70 Gy to prostate and vesicles. In two different phase I studies, hyperthermia was added to the radiotherapy. Twelve patients were treated with one interstitial hyperthermia treatment, lasting 60 min. Fourteen patients have been treated with five regional hyperthermia treatments, lasting 75 min each. In both hyperthermia studies, the body, bladder and rectum temperatures remained below safety limits. Patients treated with radiotherapy alone (n = 58) or combined with regional (n = 8) or interstitial hyperthermia (n = 12) completed the European Organization for Research and Treatment of Cancer (EORTC) core questionnaire (C30 + 3), the EORTC prostate cancer module (PR25) and the Rand 36 health survey before treatment and 1 and 6 months after completion of treatment. Analysis of Variance (ANOVA) for repeated measurements has been performed to describe the data. RESULTS: All patient groups were comparable concerning patient characteristics. No significant interaction or difference in QoL has been noticed between the two hyperthermia patient groups and the patient group without hyperthermia. Therefore, all groups were analysed together (n = 78) to detect QoL changes in time. A deterioration of QoL has been measured from baseline to 1 month after treatment. Fatigue, pain, urinary symptoms, bowel symptoms and financial difficulties increased significantly. Social, physical and role functioning worsened significantly. No differences in QoL were measured 6 months after treatment compared to the baseline measurement, except for a decrease in sexual activity. CONCLUSIONS: After radiotherapy with or without hyperthermia only a temporary deterioration of QoL occurs, concerning social, psychological and disease related symptoms. Additional hyperthermia does not seem to decrease QoL.