The Hopeless Case? Palliative Cryoablation and Cementoplasty Procedures for Palliation of Large Pelvic Bone Metastases

Background: Metastases to the bone are common in cancer patients, and it has been estimatedthat up to 50% of patients with pelvic bone metastases will not achieve adequate pain control withmedications alone. This has led to a paradigm shift over recent years towards the use and developmentof minimally invasive image-guided treatment options for palliation of bony metastases. Despite thesedevelopments, large metastatic lesions are still often considered to be “hopeless cases” that wouldgarner little to no benefit from image-guided intervention. This study is the first large series to describethe novel use of combination percutaneous cryoablation and cementoplasty for palliation of such largemetastases to the pelvis.Objectives: We aim to evaluate the efficacy and safety of image-guided percutaneous cryoablationand cementoplasty for palliation of large pelvic bone metastases.Study Design: This retrospective analysis was approved by our institutional review board. This studywas conducted from January 2013 to December 2016, where consecutive patients referred for painmanagement of large pelvic bone metastases underwent combination percutaneous cryoablation andcementoplasty.Setting: This study took place at a tertiary care center after patients were referred following formalreview from a multidisciplinary conference, which was comprised of interventional radiologists, painmanagement and palliative care physicians, radiation and medical oncologists, and when available,anesthesiologists.Methods: Forty-eight patients (36 men and 12 women) with a mean cohort age of 77.5 years(range: 52 – 89 years) were referred from the multidisciplinary conference for palliation of pelvic bonemetastases. The inclusion criteria included patients with metastases greater or equal to 5.0 cm andsignificant pain refractory to conventional pain management regimens. All of the patients were deemednot to be surgical candidates. Mean pain scores were collected at numerous time-points along withprocedural technical success rates and complication rates.Results: Combination cryoablation and cementoplasty was performed on 48 consecutively referredpatients with a 100% technical success rate and no immediate complications. The pain levelsdemonstrated a significant decrease (P < 0.001) following intervention, with mean pain scores of 7.9(range: 5 – 10) and 1.2 (range: 0 – 7) throughout the week prior to intervention and at 24 hours postintervention, respectively. The post-intervention pain scores remained stable at 1 to 9 weeks followup (mean: 4.1 weeks). Three patents (6.3%) reported no change in pain following the intervention;however, no patients reported worsened pain.Limitations: The limitations of this study include its retrospective nature and the length of follow-up,which was often restricted given the life expectancy of our patient cohort.Conclusion: Combination cryoablation and cementoplasty is a novel and efficacious treatment optionfor palliation of large pelvic bone metastases. Marked improvements in pain, as well as mobility andquality of life, are often attainable.Key words: Pain, palliative care, palliation, percutaneous, cryoablation, cementoplasty, metastases,pelvis, interventional radiology, thermal ablation