The role of dose volume histograms and TGF-β in the prediction of radiation pneumonitis: a pilot study

METHODS

Fifteen NSCLC patients treated with 3D conformal radiotherapy
were included in the study. Radiotherapy dose was a
median 60 Gy. Mean lung dose (MLD), V₂₀ and V₃₀ were calculated
from both ipsilateral and contralateral lung DVH.
TGF-β levels were studied with ELISA.

RESULTS

Median follow-up was 16 months (range 10-55). Radiation
pneumonitis was diagnosed in three patients (6, 9, 12
months). Dose parameters of ipsi- and contralateral lungs
revealed that higher MLD, V₂₀, V₃₀ values in contralateral
lung were statistically significant for pneumonitis (p<0.005).
There was no statistical correlation between plasma TGF-β
levels and radiation pneumonitis.

CONCLUSION

In this study, high doses in contralateral lung (MLD, V₂₀,
V₃₀), when compared with ipsilateral lung, were shown as
risk factors for developing radiation pneumonitis. TGF-β levels
seem non-predictive for pneumonitis in the short term.

Keywords: Dose volume histograms; radiation pneumonitis; MLD, V₂₀, V₂₀; TGF-&#946;