A national dose analysis of guided tumor destruction: influence of sex, age, localization and destruction technique used.

Abstract

Percutaneous destructions of tumor lesions by ablation (microwave, radiofrequency or cryoablation) under computed tomography (CT) guidance allow high efficiency with minimally-invasive techniques, and acute needle placement and follow-up during procedure. This study investigated the impact of patient and technique parameters on the dose delivered during these procedures under CT guidance. Data were extracted from a previous nationwide retrospective study. Patients who underwent percutaneous destruction of bone lesions, abdominal and lung tumors were included. Univariate and multivariate linear regression of the dose length product (DLP) log were performed, according to patient's gender, age, lesion location, destruction technique, adjusted to the participating center. A total of 822 patients (556 men), of mean age 62±14 years, were included: 150 patients had bone lesions, 463 abdominal and 209 thoracic tumors. The mean DLP was 991.6±979.0 mGy·cm for patients with bone lesions, 2,130.7±2,051.8 mGy∙cm for abdominal tumors and 825.2±545.4 mGy·cm for lung tumors. In multivariate analysis, the age was significantly associated with higher DLP for bone (P=0.0082) but not for abdominal and thoracic lesions; the DLP was significantly higher in men for abdominal tumors (P<0.0001) while sex had no impact on the dose for bone and thoracic lesions. The dose depended on the lesion location only for bone (P<0.0001) percutaneous destructions. The technique was not correlated to DLP for all lesions. Patient and tumor characteristics such as sex, age and lesion location impacted on the dose delivered during percutaneous destructions of bone, abdominal and thoracic lesions, but not the destruction technique used. Further studies are needed to propose sharper reference dose levels.