Drug distribution in intracystic 32P colloid radiotherapy for treatment of craniopharyngioma:a clinical study

Chang Hongbo; Gao Ming; Zhao Siyuan; Lu Wangsheng; Wang Yaming; Zhao Hulin; Tian Zengmin

doi:10.11850/j.issn.1009-122X.2014.07.001

Abstract：Objective To research the influence of different doses and craniopharyngioma cavity volumes on the drug distribution inside the capsule and cerebrospinal fluid leakage of 32P colloid inside the capsule, so as to provide clinical guidance for the surgical puncture path selection and operation skills control. Methods Clinical data of 40 patients with first onset or recurrent cystic craniopharyngioma were analyzed prospectively, and the patients were divided into 4 groups according to the therapeutic dose (mCi): 0.5, 1.0, 1.5 and 2.0 mCi groups. After 32P colloid diluted with iopamidol 300 injection by 1:1 proportion, the mixture was injected into the capsule for stereotactic radiotherapy, and the situation of drug distribution and leakage were observed by CT scan 2 h after the operation. The statistical differences were compared between the groups. Results There were 6 patients in 2.0 mCi group, 2 in 1.5 mCi group and 1 in 1.0 mCi group showed uneven distribution of drugs and cerebrospinal fluid leakage inside the capsule, due to puncture pathway in the brain could not avoid entering into the ventricle, and the capsule volume had no obvious shrink after leakage. Even distribution of drug and no leakage were seen in the other patients, and the postoperative capsule volume significantly diminished. There was statistical significance in differences of cerebrospinal fluid leakage rate between 2.0 and both 1.0 and 0.5 mCi groups (P<0.05). Conclusion The bigger the cystic craniopharyngioma cavity volume and the greater the 32P colloid dose is, the higher the incidence of cerebrospinal fluid leakage inside the capsule and the more uneven the distribution of drug is.