Correlation Between Dose Volume Parameters and Radiation Pneumonitis in Elderly Patients with Esophageal Cancer After Three-dimensional Conformal Radiotherapy

Objective To analyze the correlation between ≥grade 2 radiation pneumonitis (RP) and dose volume parameters of elderly patients with esophageal cancer after three-dimensional conformal radiotherapy.

Methods We collected the data of 250 elderly patients with esophageal cancer who received three-dimensional conformal radiotherapy from different medical centers. The clinical features of patients were analyzed by Chi-square test while dose volume parameters were analyzed by Logistic univariate and multivariate analyses. ROC curve was used to determine the best cut-off value.

Results After three-dimensional conformal radiotherapy, 20% of patients developed ≥grade 2 RP. Univariate analysis showed that bilateral pulmonary V5, V10, V20, V30 and mean lung dose were associated with ≥grade 2 RP but multivariate analysis revealed that only V5 and V20 were independent relevant factors of RP. ROC curve indicated that the best cut-off value was V5 < 52.9% and V20 < 23.2%.

Conclusion Bilateral pulmonary V5 and V20 are independently related to ≥grade 2 RP in elderly patients with esophageal cancer after 3-D conformal radiotherapy.