PET/CT-guided biopsies of metabolically active bone lesions: applications and clinical impact

Purpose: In a minority of cases a definite diagnosis and stage grouping in cancer patients is not possible based on the imaging information of PET/CT. We report our experience with percutaneous PET/CT-guided bone biopsies to histologically verify the aetiology of hypermetabolic bone lesions. Methods: We retrospectively reviewed the data of 20 consecutive patients who underwent multimodal image-guided bone biopsies using a dedicated PET/CT system in a step-by-step technique. Technical and clinical success rates of PET/CT-guided biopsies were evaluated. Questionnaires were sent to the referring physicians to assess the impact of biopsies on patient management and to check the clinical need for PET/CT-guided biopsies. Results: Clinical indications for biopsy were to histologically verify the aetiology of metabolically active bone lesions without a morphological correlate confirming the suspicion of metastases in 15 patients, to determine the origin of suspected metastases in 3 patients and to evaluate the appropriateness of targeted therapy options in 2 patients. Biopsies were technically successful in all patients. In 19 of 20 patients a definite histological diagnosis was possible. No complications or adverse effects occurred. The result of PET/CT-guided bone biopsies determined a change of the planned treatment in overall 56% of patients, with intramodality changes, e.g. chemotherapy with palliative instead of curative intent, and intermodality changes, e.g. systemic therapy instead of surgery, in 22 and 50%, respectively. Conclusion: PET/CT-guided bone biopsies are a promising alternative to conventional techniques to make metabolically active bone lesions—especially without a distinctive morphological correlate—accessible for histological verification. PET/CT-guided biopsies had a major clinical impact in patients who otherwise cannot be reliably stage grouped at the time of treatment decisions