Guidelines for Complications of Cancer Treatment Vol VIII Part B

eceived elective nodal irradiation (ENI). Their treatment planswere subsequently recapitulated using a three-dimensionaltreatment planning system. Twenty patients were planned usingthis system from the outset. For these patients, elective nodalirradiation was omitted. Dose-volume histograms (DVH) wereconstructed and several parameters analyzed for their abilityto predict for the development of pneumonitis. RESULTS:Univariate analysis revealed that the percentage lung volumereceiving more than 20 Gy (V20) and the mean lung dose areof predictive value for the development of pneumonitis afterCHART. There is a strong correlation between these twoparameters. Importantly, partial volume lung irradiation usingCHART appears to be better tolerated than conventionallyfractionated radiotherapy. The omission of ENI considerablyreduces V20. Using a commonly employed 3-beam techniqueit was also noted that the shape of the planning target volume(PTV) in the transverse plane (expressed as an elliptical index)affects the conformity of the V20 isodose to the PTV. Thisinfluences the scope for dose escalation with irregularly shapedtumors.CONCLUSIONS: In relation to acute radiation pneumonitis,CHART appears to have a superior therapeutic index thanconventionally fractionated radiotherapy. V20 and mean lungdose are useful factors for predicting the risk of thiscomplication. The use of these parameters will aid the selectionof optimal treatment plans and provides a basis for future doseescalation studies.Int J Radiat Oncol Biol Phys. 1999 Sep 1;45(2):323-9.Clinical dose-volume histogram analysis for pneumonitis after3D treatment for non-small cell lung cancer (NSCLC).325