Troponin T-release associates with cardiac radiation doses during adjuvant left-sided breast cancer radiotherapy

Background Adjuvant radiotherapy (RT) for left-sided breast cancer increases cardiac morbidity and mortality. For the heart, no safe radiation threshold has been established. Troponin T is a sensitive marker of myocardial damage. Our aim was to evaluate the effect of left-sided breast cancer RT on serum high sensitivity troponin T (hscTnT) levels and its association with cardiac radiation doses and echocardiographic parameters. Methods A total of 58 patients with an early stage, left-sided breast cancer or ductal carcinoma in situ (DCIS) who received adjuvant breast RT without prior chemotherapy were included in this prospective, non-randomized study. Serum samples were taken before, during and after RT. An increase of hscTnT >30 % was predefined as significant. A comprehensive 2D echocardiograph and electrocardiogram (ECG) were performed before and after RT. Dose-volume histograms (DVHs) were generated for different cardiac structures. Results The hscTnT increased during RT from baseline in 12/58 patients (21 %). Patients with increased hscTnT values (group A, N = 12) had significantly higher radiation doses for the whole heart (p = 0.02) and left ventricle (p = 0.03) than patients without hscTnT increase (group B, N = 46). For the left anterior descending artery (LAD), differences between groups A and B were found in volumes receiving 15 Gy (p = 0.03) and 20 Gy (p = 0.03) Furthermore, after RT, the interventricular septum thickened (p = 0.01), and the deceleration time was prolonged (p = 0.008) more in group A than in group B. Conclusions The increase in hscTnT level during adjuvant RT was positively associated with the cardiac radiation doses for the whole heart and LV in chemotherapy-naive breast cancer patients. Whether these acute subclinical changes increase the risk of excessive long-term cardiovascular morbidity or mortality, will be addressed in the follow-up of our patients.BioMed Central open acces

Une nouvelle forme sexuée du complexe

L’obtention de 2 souches test, SA181 « + » et SA187 « — », de « Trichophyton mentagrophytes » douées d’un pouvoir sexué très élevé permet de décrire une nouvelle espèce sexuée de dermatophyte : Arthroderma vanbreuseghemii. En confrontant 82 souches du complexe T. mentagrophytes à ces 2 souches test, nous y avons trouvé 30 souches compatibles. L’étude morphologique de ces souches montre que A. vanbreuseghemii a, mis à part les « pléomorphes », 4 formes conidiennes : forme sauvage, forme granulosum-asteroides, forme couleur de pêche et forme radians. Toutes ces formes conidiennes sont distinctes de celles de Arthroderma benhamiae ou de Arthroderma simii. Aucune des souches de A. vanbreuseghemii n’est compatible ni avec A. benhamiae, ni avec A. simii. A. vanbreuseghemii est bien pathogène pour l’homme et pour des animaux. Tous ces fais indiquent que A. vanbreuseghemii doit occuper la place centrale au sein du complexe T. mentagrophytes