Permanent seed implant brachytherapy in low-risk prostate cancer: Preoperative planning with 145 Gy versus real-time intraoperative planning with 160 Gy.

AIM: The present retrospective study was to compare toxicity and survival outcomes in a group of low-risk PCa patients treated with either the preoperative planning technique (145 Gy) or the real-time IoP technique (160 Gy). BACKGROUND: The two most common permanent seed implantation techniques are preoperative planning (PP) with 145 Gy and real-time intraoperative planning (IoP) with 160 Gy. Although IoP has largely replaced PP at many centres in recent years, few studies have directly compared these two techniques. MATERIALS AND METHODS: Retrospective study of 408 patients with low-risk PCa treated with permanent seed implant brachytherapy at our institution between October 2003 and December 2014. Of these, 187 patients were treated with PP at a dose of 145 Gy while 221 received real-time IoP with 160 Gy. RESULTS: At a median follow up of 90 months, 5- and 8-year rates of biochemical relapse-free survival (BRFS) were 94.8% and 86% with the IoP technique versus 90.8% and 83.9%, respectively, with PP. The maximum dose to the urethra was <217 Gy with both techniques. Despite the higher dose, IoP did not cause any significant increase in toxicity (p = 0.11). CONCLUSIONS: The present study shows that real-time intraoperative brachytherapy at a dose of 160 Gy yield better biochemical control than preoperative planning at 145 Gy. In addition, urinary toxicity did not increase, despite the dose escalation, probably because the dose constraints to the urethra were met despite the increased dose escalation. These findings support the use of real-time IoP.

Evaluation of acute skin toxicity in breast radiotherapy with a new quantitative approach.

BACKGROUND AND PURPOSE: Current criteria to evaluate acute radiodermatitis are highly subjective so quantification of physiological parameters is needed. We describe a non-invasive method of assessing skin microcirculation in breast cancer patients treated with hypofractionated radiotherapy and correlate them with the CTCAE scale. METHODS: Prospective study of 63 patients where blood flow was measured with real-time laser Doppler flowmetry (LDF) at baseline, weekly, and 3-months post-radiotherapy. Skin toxicity was assessed with the microcirculation index (MCI), a novel index based on blood flow parameters obtained via LDF. RESULTS: MCI was positively correlated (R=0.647; p<0.001) with the dose. Changes in MCI from baseline to the end of radiotherapy and at 3-months post-radiotherapy were significant (p<0.001). All CTCAE groups experienced a significant increase in MCI values from baseline to end of radiotherapy (p<0.001 for CTCAE grades 0 and 1; and p=0.028 for the grade 2 group). Significant differences in MCI values were observed among CTCAE groups at the end of radiotherapy (p=0.016). CONCLUSIONS: LDF is an accurate and objective measure of changes in blood flow. The comparison with the CTCAE shows the limitations of this subjective way of classifying patients. LDF is the first step for future studies of radiodermatitis treatments and prevention.

Fractionated stereotactic radiotherapy plus bevacizumab after response to bevacizumab plus irinotecan as a rescue treatment for high-grade gliomas.

AIM: To evaluate the possibility of implementing a new scheme of rescue treatment after relapse or progression of high-grade glioma (HGG) treated at the first-line with bevacizumab and irinotecan (BVZ+CPT11), evaluating the response and toxicity of associating BVZ and fractionated stereotactic radiotherapy (BVZ+FSRT). MATERIALS AND METHODS: We retrospectively analysed data from 59 patients with relapse of HGG. Nine patients with HGG relapse after treatment using the Stupp protocol that were treated with BVZ+CPT11 for progression between July 2007 and August 2012, after which the response was assessed according to the Revised Assessment in Neuro-Oncology (RANO) criteria. BVZ was administered at a dose of 10 mg/kg and FSRT up to a prescribed dose of 30 Gy, 500 cGy per fraction, three days a week. The median follow-up was 38 months. RESULTS: The treatment was well-tolerated by all patients. The response after nuclear magnetic resonance imaging (MRI) at 3-6 months was progression in two patients, stable disease in four, and three patients had a partial response. The median overall survival (OS) from diagnosis until death or the last control was 36.8 months. The median progression-free survival (PFS) was 10.8 months. The results from tumour sub-group analysis indicated that the PFS was not statistically significant although it seemed that it was higher in grade-III. The OS was higher in grade-III gliomas. CONCLUSIONS: The combination of BVZ+FSRT as a second-line HGG relapse rescue treatment is well-tolerated and seems to offer promising results. We believe that multi-centre prospective studies are needed to determine the long-term efficacy and toxicity of this therapeutic approach.

Tumor bed segmentation: first step for partial breast irradiation.

INTRODUCTION: In breast IMRT simultaneous integrated boost (SIB) treatment and accelerated partial breast irradiation (APBI), proper delineation of the tumor bed is necessary. Conservative oncoplastic surgery causes changes in peritumoral breast tissue that complicates locating the site of the tumor. Nevertheless, there are still centers that do not use surgical clips to delineate the site. This study aims to show how the lack of clips affects the techniques of SIB and APBI in terms of dose distribution and safety margins in the tumor bed. MATERIALS AND METHODS: On 30 patients, the defining of the tumor bed obtained from the pre-surgery CT scan to that outlined on the basis of clips on the post-surgery CT was compared. Tumor bed deviation from the original tumor site was quantified. In addition, the margins to the original tumor site necessary to guarantee the coverage of the tumor bed were calculated. RESULTS: Variations were detected in the distances between geometric centers of the PTV (minimum 0.5-maximum 3 cm). The maximum margin necessary to include the entire tumor bed was 4.5 cm. Lesions located in the upper outer quadrant required the widest margins. If margins are not added, the tumor bed volume defined with clips will be underdosed. CONCLUSIONS: The definition of the tumor bed based on studies before surgery does not have the necessary accuracy. Clips need to be placed in the surgical bed to identify the changes occurring after the restorative mammoplasty. Without clips, SIB and APBI are not safe.