Claudio Degli Esposti

Relationships between bladder dose–volume/surface histograms and acute urinary toxicity after radiotherapy for prostate cancer

BACKGROUND AND PURPOSE DUE01 is an observational study aimed at developing predictive models of genito-urinary toxicity of patients treated for prostate cancer with conventional (1.8-2Gy/fr, CONV) or moderate hypo-fractionation (2.35-2.7Gy/fr, HYPO). The current analysis focused on the relationship between bladder DVH/DSH and the risk of International Prostate Symptoms Score (IPSS)⩾15/20 at the end of radiotherapy. MATERIALS AND METHODS Planning and relevant clinical parameters were prospectively collected, including DVH/DSH, LQ-corrected (DVHc/DSHc) and weekly (DVHw/DSHw) histograms. Best parameters were selected by the differences between patients with/without IPSS⩾15/20 at the end of radiotherapy. Logistic uni- and backward multi-variable (MVA) analyses were performed. RESULTS Data of 247 patients were available (CONV: 116, HYPO: 131). Absolute DVHw/DSHw and DVHc/DSHc predicted the risk of IPSS⩾15 at the end of radiotherapy (n=77/247); an MVA model including baseline IPSS, anti-hypertensive, T stage, the absolute surface receiving ⩾8.5Gy/week and ⩾12.5Gy/week was developed (AUC=0.78, 95% CI: 0.72-0.83). Similar AUC values were found if replacing DSHw with DVHw/DVHc/DSHc parameters. The impact of dose-volume/surface parameters remained when excluding patients with baseline IPSS⩾15 and in HYPO. IPSS⩾20 at the end of radiotherapy (n=27/247) was mainly correlated to baseline IPSS and T stage. CONCLUSIONS Although the baseline IPSS was the main predictor, constraining v8.5w<56cc and v12.5w<5cc may significantly reduce acute GU toxicity.

Analysis of inter-fraction setup errors and organ motion by daily kilovoltage cone beam computed tomography in intensity modulated radiotherapy of prostate cancer

BackgroundIntensity-modulated radiotherapy (IMRT) enables a better conformality to the target while sparing the surrounding normal tissues and potentially allows to increase the dose to the target, if this is precisely and accurately determined. The goal of this work is to determine inter-fraction setup errors and prostate motion in IMRT for localized prostate cancer, guided by daily kilovoltage cone beam computed tomography (kVCBCT).MethodsSystematic and random components of the shifts were retrospectively evaluated by comparing two matching modalities (automatic bone and manual soft-tissue) between each of the 641 daily kVCBCTs (18 patients) and the planning kVCT. A simulated Adaptive Radiation Therapy (ART) protocol using the average of the first 5 kVCBCTs was tested by non-parametric bootstrapping procedure.ResultsShifts were < 1 mm in left-right (LR) and in supero-inferior (SI) direction. In antero-posterior (AP) direction systematic prostate motion (2.7 ± 0.7 mm) gave the major contribution to the variability of results; the averages of the absolute total shifts were significantly larger in anterior (6.3 ± 0.2 mm) than in posterior (3.9 mm ± 0.2 mm) direction. The ART protocol would reduce margins in LR, SI and anterior but not in posterior direction.ConclusionsThe online soft-tissue correction based on daily kVCBCT during IMRT of prostate cancer is fast and efficient. The large random movements of prostate respect to bony anatomy, especially in the AP direction, where anisotropic margins are needed, suggest that daily kVCBCT is at the present time preferable for high dose and high gradients IMRT prostate treatments.

Multi-variable models predicting specific patient-reported acute urinary symptoms after radiotherapy for prostate cancer: Results of a cohort study.

PURPOSE A prospective trial started in 2010, aiming at developing models for urinary toxicity and erectile dysfunction after radiotherapy for prostate cancer. This analysis is finalised at highlighting correlations between clinical/dosimetric factors and acute urinary specific symptoms, as measured by single questions of the International Prostate Symptom Score (IPSS). MATERIALS/METHODS IPSS was prospectively collected before and at the end of radiotherapy; absolute weekly bladder dose-surface histograms (DSHw) were chosen as dosimetric descriptors. Relevant clinical factors were prospectively gathered. Backward feature selection was used to identify variables to be included in logistic models for moderate-severe (scores⩾4) urinary symptoms. RESULTS Complete data of 262 patients (120 conventional fractionation, 142 hypofractionation) were available. Smoking was a strong predictor for feeling of incomplete emptying, frequency, intermittency, urgency and straining; neoadjuvant hormonal therapy and use of antihypertensive drugs were risk factors for intermittency and weak stream, respectively. The baseline score was a major predictor for all symptoms with the exception of intermittency. DSHw were correlated to increased risk of frequency, intermittency, urgency and nocturia. Most models showed moderate-high discrimination (AUC≈0.60-0.79). CONCLUSIONS Smoking and other clinical and dosimetric factors predict for specific moderate-severe acute urinary symptoms; baseline condition heavily modulated the risk in most endpoints.

Multi-variable models of large International Prostate Symptom Score worsening at the end of therapy in prostate cancer radiotherapy

PURPOSE/OBJECTIVE Prospectively assessing clinical/dosimetry factors affecting the acute worsening of urinary functionality after radiotherapy for prostate cancer. MATERIAL/METHODS DUE01 population was considered, including patients treated with conventional or moderate hypo-fractionation (2.2-2.7 Gy/fr). Relevant clinical factors were collected, urinary symptoms were self-reported through the International Prostate Symptom Score (IPSS) before and at the end of radiotherapy; while absolute weekly dose-surface histograms (DSHw) were chosen as dosimetry descriptors. An IPSS increase of at least 10 and 15 points (ΔIPSS ⩾ 10 and ΔIPSS ⩾ 15) were chosen as endpoints. Patients with baseline IPSS>20 were excluded. Relevant factors were chosen through a bootstrap-based in silico methodology. RESULTS Complete information was available for 380 patients: 77/380 (20%) and 28/380 (7%) with ΔIPSS ⩾ 10 and ΔIPSS ⩾ 15, respectively. Neoadjuvant hormone was protective (OR=0.49 and 0.69). DSHw at 8.5 Gy/week and 12 Gy/week were risk factors, with additional risk for patients who use cardiovascular drugs and anti-hypercholesterolemia drugs. In the hypo-fractionated subgroup (n=209) the role of cardiovascular drugs (OR=2.16) for ΔIPSS ⩾ 10 and anti-hypercholesterolemia drugs (OR=2.80) for ΔIPSS⩾15, together with DSHw (10 Gy/week and 12.5 Gy/week, respectively), was confirmed. CONCLUSION Current study shows a dose-surface/volume effect for acute large worsening of urinary functionality; several clinical variables largely impact the risk and especially all the factors related with vascular diseases.

Unusual case of spindle cell sarcoma metastases to right ventricle: a case report and a literature review

Cardiac metastases from sarcoma are uncommon. Due to their rarity there is not a standard of care. However, complete cardiac metastases resection is the best option but most of patients has widespread disease. In these patients palliative radiotherapy (RT) might improve symptoms and prevent further cardiac function decline. Here we present the case of a symptomatic 30-year-old woman with spindle cell sarcoma metastasis of right ventriculum and widespread disease. The patient received radiotherapy to the heart with palliative intent. Cardiac metastases represent a challenging clinic problem. Treatment should be individualized in a multidisciplinary setting, when possible surgery seems to be the best options. However, radiotherapy even in case of widespread disease can improve clinical control symptoms by reducing the mass effect.

Modeling acute urinary toxicity after radiotherapy for prostate cancer.

156 Background: DUE-01 is a multi-centric observational study aimed at developing predictive models of genito-urinary toxicity and erectile dysfunction for prostate cancer patients treated with conventional (1.8-2Gy/fr, CONV) or moderate hypofractionation (2.5-2.7Gy/fr, HYPO). Current analysis focused on modelling the relationship between the risk of IPSS≥15 (IPSS15end) at the end of radiotherapy and clinincal/dosimetric risk factors. Methods: Planning data and relevant clinical factors were prospectively collected, including DVH/DSH referred to the whole treatment and to the weekly delivered dose (DVHw/DSHw). Best discriminating DVH/DSH parameters were selected by the differences between patients with/without IPSS15end=1 (t-test). Bootstrap variable selection techniques (300 resamples) in the framework of logistic backward feature selection was used to improve model building (El Naqa, IJROBP 2006). Graphical and quantitative analyses of the variable selection process applied to bootstrap data replicates ...