Dose-effect relations for early XXXX after irradiation for @entity706 and @entity0 .

@entity1 @entity0 @entity706 @entity651
PURPOSE: To quantify the influence of treatment- and @entity1 -related factors on the severity of early @entity651 and to establish whether regional differences are present for local dose-effect relations for early radiation-induced @entity651 . METHODS: Forty-two @entity1 with @entity706 and 40 @entity0 @entity1 were examined prior to and 3 months after radiotherapy. The @entity706 @entity1 were irradiated with mantle fields to an average dose of 38 Gy and the @entity0 @entity1 were irradiated with internal mammary node fields with or without tangential breast fields to an average dose of 50 Gy. Dose-effect relations for local perfusion, ventilation and density changes were determined using correlated single photon emission computed tomography (SPECT) and CT data. A multivariate analysis was performed to study the influence of irradiated volume, chemotherapy (CMF and MOPP/ABV), smoking, age and gender. In addition, dose-effect relations for different regions in the lung were determined. RESULTS: A similar and almost linear increase of early functional changes as a function of radiation dose was observed for perfusion and ventilation, whereas the shape of the dose-effect relation and the magnitude of early structural changes were different for density. For the three end-points studied, regional differences in radiosensitivity could not be demonstrated. For the posterior lung region compared to the anterior lung region, however, a difference was observed, which could be attributed to a gravity-related effect in the measuring procedure. Local structural changes (density) were significantly smaller for smokers (P = 0.002) and young @entity1 (P = 0.007), whereas the CMF chemotherapy regimen given after radiotherapy (P = 0.017) significantly increased the amount of functional changes (perfusion). The magnitude of local pulmonary changes was independent of the irradiated volume, the MOPP/ABV chemotherapy regimen and gender. CONCLUSION: The dose-effect relations for early radiation-induced local pulmonary changes were independent of the irradiated volume, MOPP/ABV, gender and lung region. CMF, smoking and age influenced the magnitude of early pulmonary changes and should be taken into account in dose-escalation protocols.
