Tumor Seeding along the Puncture Tract in CT-Guided Interstitial High-Dose-Rate Brachytherapy

Purpose To quantify the occurrence of tumor seeding in computed tomography (CT)-guided high-dose-rate brachytherapy (HDRBT) and to identify potential risk factors. Materials and Methods CT-HDRBT is a minimally invasive therapeutic option for local ablation of unresectable tumors. The procedure involves CT-guided placement of an enclosed catheter and high-dose-rate brachytherapy using iridium-192. Transcutaneous puncture of a tumor with subsequent retraction of the applicator has the potential risk of tumor seeding along the puncture tract. A total of 1,765 consecutive CT-HDRBT procedures were performed at this center between 2006 and 2017 and were retrospectively analyzed. In addition, a distinction was made between whether the puncture tract was irradiated or not. Follow-up imaging datasets were evaluated for tumor seeding along the former puncture tracts. Descriptive and exploratory statistical analyses of the data were performed. Results Tumor seeding was observed in 25 cases (25 of 1,765 cases [1.5%]). A total of 0.008 cases occurred per person-age. Patient age was identified as a potential risk factor with an odds ratio of 1.046 (95% confidence interval, 1.003–1.091; P = .04). There were no differences between whether the puncture tract was irradiated or not (P = .552). Conclusions Tumor seeding along the puncture tract can occur in CT-HDRBT but is rare.