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Various meta-analyses and studies based on historical registries have shown an excess of mortality and significant cardiovascular (CV) morbidity in breast cancer (BC) patients who receive adjuvant radiotherapy (RT) on the left side. However, these patients were treated with obsolete RT techniques, with conventional fractionation and without a precise knowledge of the heart dose-volume histograms (DVH) or CV-risk factors. We now know that the use of ultra-conformal techniques (IMRT) has led to a significant decrease in the heart dose, as reflected in the DVHs. In parallel, hypofractionated protocols -which result in lower EQD2 in organs at risk- have become the standard of care. The aim of our study was to assess whether the combination of both could reduce CV events compared to historical series and to identify clinical or dosimetric factors that could have a negative impact. All BC patients at our institution who received hypofractionated (40.05Gy/15sessions) adjuvant forward-planned IMRT after conserving surgery were included. Patients in indication for elective lymph node RT and those who had received previous mediastinal RT were excluded. 882 patients with invasive BC or DCIS were analyzed (450 right breast; 432 left). After a median follow-up of 8ys (maximum 14), 35 CV events were identified (5 myocardial infarction/angina, 20 arrhythmias, 2 severe valvular disease and 7 "other non-ischemic"). No statistically significant differences were observed according to breast laterality (P = 0.15). With regard to heart DVHs, none of those analyzed had a deleterious effect, although there was a slight and progressive trend towards statistical significance (Table). Patient-dependent CV risk factors that were found to have a significant impact on the incidence of late CV events were dyslipidemia, hypertension, family history of heart disease and overweight/obesity (P = 0.03, <0.001, <0.001 and 0,02 respectively). Although the deleterious impact of thoracic RT on CV late events is well known, in our cohort it has been shown to be less determinant than patient-dependent baseline risk factors for any CV event. Further long-term follow-up will be necessary to determine whether these results are sustained over time and, if event curves continue to diverge, to assess the extent to which they do so. On the other hand, a precise understanding of the impact of CV risk factors may help to design targeted primary prevention strategies from which BC patients may benefit. [ABSTRACT FROM AUTHOR]

To analyzed the Apparent Diffusion Coefficient (ADC) as an early prognostic factor of response in patients with prostate cancer treated with radiotherapy (RT) and androgen deprivation therapy (ADT). All prostate cancer patients classified as high or very high and unfavorable intermediate-risk according to NCCN criteria that received ADT and RT between 2008 and 2019 in whom an multiparametric magnetic resonance imaging (mpMRI) was performed were included. The ADC values were calculated by mpMRI performed 6 months after RT. We assessed the differences in the mean ADC values between patients with or without progression and/or local relapse after 10 years. Receiver-operating characteristics (ROC) analysis were used to obtain ADC cut-off values to predict 10y-progression-free survival and 10y-local progression survival in these patients. Additionally, differences in ADC values between diagnosis and post-RT were assessed. We retrospectively evaluated 98 consecutive patients, 25(25.5%) patients were intermediate-risk and 73 (74.5%) patients were high-risk. The median PSA at diagnosis was 10.15ng/ml [6.93-21]. After a mean follow-up of 95.36 months (SD:30.54), 19 (19.39%) patients progressed,10y biochemical relapse-free survival was 76.5%, 10y-PFS was 75.6%, 10y-LRFS was 93.8%, 10y metastasis-free survival was 85.5%, 10y overall survival was 89.5%. The mean ADC values at diagnosis and post-RT was 0.81 ± 0.18 vs 1.30 ± 0.18 x10-3 mm2/sec, respectively (p<0.001); and the mean relative increase in ADC values was 70.11% (SD:46.80). A statistically significant difference in post-RT ADC values was noted between patients with and without recurrence (1.20 ± 0.10 vs 1.30 ± 0.20 x10-3 mm2/sec, p = 0.004). We also found significant differences in ADC values between patients with and without local relapse (1.10 ± 0.10 vs 1.30 ± 0.20 x10-3 mm2/sec, p = 0.020). The ROC analysis identified post-RT ADC cut-off point of 1.24x10-3 mm2/sec for progression (area under curve (AUC) 0.705, sensitivity (S)72.2%, positive predictive value (PPV): 87.69%)) and a cut-off point of 1.11x10-3 mm2/sec for local relapse (AUC: 0.843, S:89.4%, PPV: 98.82%). 10-y LRFS was 66.8% and 97.7% in patients with post-RT ADC values below and above 1.11x10-3 mm2/sec, respectively (HR:724.8 [31.28-16.793]; p<0.001). 10-y PFS was 58.6% and 85.6% in patients with post-RT ADC values below and above 1.24 10-3 mm2/sec (HR: 2.916 [1.113-7.644] p = 0.015). Patients whose ADC values increased >95% between diagnosis and post-RT had a lower risk of relapses (4.76% vs.26.56%, p < 0.001). This is the first study with a long follow-up that shows that post-RT ADC value could be used as a prognostic factor of response in patients with prostate cancer treated with radiotherapy and ADT. [ABSTRACT FROM AUTHOR]