Effect of palliative microwave ablation on metastatic osseous pain: a single-center retrospective study.

Background: Bone is among the most common metastasis sites in patients with advanced cancer. Approximately two-thirds of bone metastasis results in pain, the majority of which is moderate to unbearable pain, which seriously affects the quality of life of patients. With the development of ablation techniques, microwave ablation (MWA) has great potential to eliminate the pain caused by bone metastasis. This study aimed to evaluate the efficacy and safety of image-guided (computed tomography-guided) percutaneous MWA for metastatic osseous pain.

Methods: This is a retrospective study involving 18 patients with cancer-related pain caused by osseous or soft tissue metastasis in the First Affiliated Hospital of Soochow University from June 2015 to October 2020. All patients (14 men and 4 women; mean age 60.2 years) underwent image-guided percutaneous palliative MWA. A paired-sample t-test was used to compare the changes in Numeric Rating Scale (NRS) score and dosage of morphine preoperatively and postoperatively (at 24 h, 3 days, and 14 days after MWA). In addition, we assessed the level of pain relief according to the patients' subjective feelings.

Results: The paired-samples t-test showed that the NRS score (6.83±0.92 vs. 1.67±0.97, P<0.05) and dosage of morphine (85.56±17.23 vs. 32.78±4.61, P<0.05) were significantly decreased at 3 days after MWA. At 14 days after MWA, the NRS score (6.83±0.92 vs. 0.94±0.87, P<0.05) and dosage of morphine (85.56±17.23 vs. 10.56±8.73, P<0.05) were also markedly decreased. Moreover, according to the patients' subjective feeling, 88.89% patients had pain relief postoperatively, while the remaining patients had no progress.

Conclusions: Image-guided (Computed Tomography-guided) percutaneous MWA can effectively relieve pain, thus improving the quality of life in patients with osseous metastasis. MWA is a feasible, safe, and effective treatment for pain caused by bone metastasis.