Comparison of dose-volume parameters for local failure in esophageal cancers treated by 3D-CRT or IMRT with different target regions / 中华放射医学与防护杂志

ABSTRACT

Objective To compare dose-volume parameters for local failure in esophageal cancers treated by there-dimensional conformal radiotherapy (3 D-CRT) or intensity modulated radiotherapy (IMRT) with different target regions.Methods A total of 244 patients with esophageal cancer (including 127 patients with local recurrence and 117 without recurrence) underwent radical 3D-CRT and IMRT were enrolled in this study.Data including dose-volume parameters and clinical features were analyzed retrospectively.Results No statistically significant differences were found in the dose-volume parameters of different planning target regions between groups with local tumor recurrence and without recurrence (P ＞ 0.05).In the elective nodal irradiation(ENI) group, neither the recurrence and the non-recurrence groups showed statistical differences in the dose-volume parameters (P ＞ 0.05).While for the involved-field iradiation(IFI) group, the GTV-V60, CTV-V60, PTV-V60 of local recurrent group were significantly lower than those in the non-recurrent group (t =-2.08,-2.19,-2.08, P ＜ 0.05).In the ENI group, radiated doses of GTV, CTV and PTV as well as dose-volume of PTV were significantly higher than the IFI group (t =1.97-3.12, P ＜ 0.05).For patients with a esophageal GTV less than 30 cm3 but without concurrent chemotherapy, radiated dose of CTV-D98％ , CTV-D95％ in the recurrent group were significantly lower than in non-recurrent group (t =-2.24--2.07, P ＜ 0.05).Conclusions Elective nodal prophylactic radiation of esophageal carcinoma could provide greater volume and doses of GTV, CTV and PTV to prescribed target regions, which may decrease local recurrence.Greater efficiency can be obtained when the primary lesion of the esophageal cancer is smaller or at an early stage, and concurrent chemotherapy is not given.