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Purpose Postoperative intravaginal brachytherapy for endometrial carcinoma is usually performed with 192 Ir high-dose rate (HDR) afterloading. A potential alternative is treatment with a broadband 50kV X-ray point source, the advantage being its low energy and the consequential steep dose gradient. The aim of this study was to create and evaluate a homogeneous cylindrical energy deposition around a newly designed vaginal applicator. Methods and Materials To create constant isodose layers along the cylindrical plastic vaginal applicator, the source (INTRABEAM system) was moved in steps of 17–19.5 mm outward from the tip of the applicator. Irradiation for a predetermined time was performed at each position. The axial shift was established by a stepping mechanism that was mounted on a table support. The total dose/dose distribution was determined using film dosimetry (Gafchromic EBT) in a "solid water" phantom. The films were evaluated with Mathematica 5.2 and OmniPro-I'mRT 1.6. The results (dose D0/D5/D10 in 0/5/10 mm tissue depth) were compared with an 192 Ir HDR afterloading plan for multiple sampling points around the applicator. Results Three different dose distributions with lengths of 3.9–7.3 cm were created. The irradiation time based on the delivery of 5/7 Gy to a 5 mm tissue depth was 19/26 min to 27/38 min. D0/D5/D10 was 150%/100%/67% for electronic brachytherapy and 140%/100%/74% for the afterloading technique. The deviation for repeated measurements in the phantom was Conclusions It is possible to create a homogeneous cylindrical dose distribution, similar to 192 Ir HDR afterloading, through the superimposition of multiple spherical dose distributions by stepping a kilovolt point source.

Purpose: Permanent interstitial brachytherapy (IB) has become an increasingly appealing therapeutic option for localized prostate cancer (LPC) among physicians and patients because it involves short hospitalization and treatment and its postulated low degree of toxicity may reduce its impact on the patients’ quality of life (QoL). The aim of this prospective study was to assess the impact of IB on the QoL of patients with LPC. Methods and Materials: A validated self-completed questionnaire was administered to the patients before and after IB and then at yearly intervals. The items allowed the identification of seven subscales exploring physical well-being (PHY), physical autonomy (POW), psychological well-being (PSY), relational life (REL), urinary function (URI), rectal function (REC), and sexual function (SEX). Results: The assessment of the QoL of 147 patients treated between May 2000 and February 2005 revealed no relevant differences in the PHY scale scores 1 month after IB or later, and the same was true of the POW, PSY, and REL scales. Urinary function significantly worsened after IB and returned to pretreatment levels only after 3 years; the impact of the treatment on the URI scale was greater in the patients with good baseline urinary function than in those presenting more urinary symptoms before IB. Rectal and sexual functions were significantly worse only at the post-IB evaluation. Conclusions: The results of the present study confirm that the impact of IB on the patients’ QoL is low despite its transient negative effects on some function, and extend existing knowledge concerning QoL after IB.