| Part One:The influence of delineator and delineating criteria on the delineation of the whole breast target after breast-conserving surgeryOBJECTIVE:To explore The influence of delineator and delineating standard on the delineation of the whole breast target after breast-conserving surgeryMETHODS:Twelve breast cancer patients with stage of T1N0M0 were choosed,for the patients, CT simulation images were got, silver clips were marked in the cavity and gross targe formed by seroma in the cavity were visible. Five delineators delineated respectively the whole breast target named as CTV, whereafter, in accordance with the criteria formulated for breast target delineation, the delineator repeat to delineate the CTV for the every patient.The differences between the volumes of CTV delineated by the different delineators with or without the criteria for the target determination were compared.RESULTS:The difference of the CTV delineated by the different delineators was statistically significant (P=0.009) without the criteria.,not statistically significant (P=0.029) with the criteria, and there was statistical significance between the volumes of CTV outlined by the same delineator with and without the criteria in three of the five delineator (P<0.05).The DI range of the target before criteria to the after was 0.645～0.917, and the difference among the five delineators was statistically significant. The MI range of the target was 0.593-0.830, and the difference among the five delineators was statistically significant.CONCLUSION:For variation of the subjective understanding, the whole breast targets have significant diference among doctors. Application of the criteria of target delineation is the key to eliminate population difference of the delineators to outline the target.Part two:Comparison of the whole breast target volume delineated according to surface marks, palpation and glandular breast tissue on CT images after breast-conserving surgeryObjectives:To compare the different methods in delineating the whole breast target volume and to explore the contouring criteria after breast-conserving surgery.Materials and methods:In 15 patients with breast cancer after breast-conserving surgery, the whole breast target was delineated in 3DCT simulation images each by three different methods. The target delineated according to the anatomical landmarks were named CTVan, according to breast palpation named CTVpa,and according to the mammary gland showing in CT images named CTVgl. The volumes of CTVan, CTVpa and CTVgl, The degree of inclusion(DI) and conformal index (CI)between the targets were measured.Results:The mean volumes of CTVan, CTVpa and CTVg1 were 792.229±282.246 mm3,618.331±295.903 mm3 and 196.825±117.618 mm3 respectively. The difference between CTVan and CTVpa had no statistical significance (P=0.08), the difference between CTVan and CTVgl, the difference between CTVpa and CTVgl both had statistical significance (P=0.000, P=0.000). CI between CTVan and CTVpa (0.644±0.122) was larger than CI between CTVan and CTVg1 (0.264±0.108) and CI between CTVpa and CTVgI (0.328±0.115) (P<0.05). DI between mutual CTVpa and CTVan (were 0.890±0.08 and 0.709±0.144), DI of CTVgl to CTVanand to CTVpa were 0.994±0.005 and 0.989±0.008。between mutual CTVgl and CTVan (0.994±0.005,0.264±0.109) and DI between mutual CTVgl and CTVpa (0.989±0.008, 0.329±0.115) had all statistical significance (P=0.006,0.000,0.000).The boundary difference of CTVan and CTVpa were:3.35±7.23mm, 5.57±13.37mm,1.75±11.62mm, and 11.25±4.07mm respectively. The cranial and medial boundary have negative correlation with CTVpa (P=0.005, P=0.015).Conclusions:Combination of the breast palpation and anatomical marks may be helpful in delineating the whole breast target volume was relatively reasonable at present. |
PDF Full Text Request