Cardiac-sparing whole lung IMRT in patients with pediatric tumors and lung metastasis: Final report of a prospective multicenter clinical trial
Mené sur 20 patients pédiatriques atteints d'une tumeur avec métastases pulmonaires, cet essai évalue la faisabilité d'une radiothérapie avec modulation d'intensité ciblant l'ensemble des poumons et dont le protocole vise à préserver les tissus cardiaques
Purpose : A prospective clinical trial was conducted for patients undergoing cardiac sparing (CS) whole lung irradiation (WLI) using IMRT. The 3 trial aims were: 1) To demonstrate the feasibility of CS IMRT with real time central quality control; 2) To determine the dosimetric advantages of WLI using IMRT compared to standard antero-posterior (AP) techniques; and 3) To determine acute tolerance and short-term efficacy after a protocol mandated minimum 2 year follow up for all patients. Methods : All patients underwent a 3D chest CT scan and a contrast-enhanced 4D gated chest CT scan using a standard gating device. The CTV was the entire bilateral 3D lung volume and the ITV was the 4D minimum intensity projection of both lungs. The ITV was expanded by 1cm to get the PTV. All target volumes, cardiac contours and treatment plans were centrally reviewed before treatment. The different cardiac volumes (V) receiving percentages (%) of prescribed RT doses on AP and IMRT WLI plans were estimated and compared. Results : The target 20 patients were accrued in 2 years. Median RT dose was 15Gy. Real time central Quality Assurance review and plan pre-approval was obtained for all patients. WLI using IMRT was feasible in all patients. Compared to standard AP WLI, CS IMRT resulted in statistically significant reduction in radiation doses to the whole heart, atria, ventricles and coronaries. One child developed cardiac dysfunction and pulmonary restrictive disease 5.5 years after CS IMRT (15Gy) and doxorubicin (375mg/m2).The 2 and 3 year lung metastasis progression free survival was 65% and 52% respectively. Conclusions : We have demonstrated the feasibility of WLI using CS IMRT and confirmed the previously reported advantages of IMRT including superior cardiac protection and superior dose coverage of 4D lung volumes. Further studies are required to establish the efficacy and safety of this irradiation technique.
https://www.redjournal.org/article/S0360-3016(18)33640-X/fulltext