Palliation of soft tissue cancer pain with radiofrequency ablation

Abstract

The purpose of this study was to analyze the feasibility, safety, and efficacy of radiofrequency ablation (RFA) to treat pain from soft tissue neoplasms. RFA was performed on 15 painful soft tissue tumors in 14 patients. Tumors varied in histology and location and ranged in size from 2 to 20 cm. Patient pain was assessed using the Brief Pain Inventory (BPI) at baseline and 1 day, 1 week, 1 month, and 3 months post RFA. All patients had unresectable tumors or were poor operative candidates whose pain was poorly controlled by conventional treatment methods. BPI scores were divided into two categories: pain severity and interference of pain. Although not all scores were statistically significant, all mean scores trended down with increased time post ablation. Based on these outcomes, RFA appears to be a low-risk and well-tolerated procedure for pain palliation in patients with unresectable, painful soft tissue neoplasms. RFA is effective for short-term local pain control and may provide another option for failed chemotherapy or radiation therapy in patients with cancer. However, pain may transiently worsen, and relief is often temporary.

Figure 1. Reduction in Pain Severity Score Post Procedure

Mean and median BPI pain severity scores over time; error bars represent the standard error of the mean. P values are for Wilcoxon signed-rank tests of the null hypothesis that the difference in the current time period minus the baseline value is equal to zero.

Figure 2. Reduction in Pain Interference Post Procedure

Mean and median BPI pain interference scores over time; error bars represent the standard error of the mean. P values are for Wilcoxon signed-rank tests of the null hypothesis that the difference in the current time period minus the baseline value is equal to zero.

Figure 3. Palliation of Kidney Metastasis Post RFA

Left: Coronal reconstruction from enhanced computed tomography (CT) scan pretreatment with a 9 cm × 7 cm metastatic melanoma lesion to the right kidney (arrow). Middle: Axial slice of non-contrast CT scan immediately following RFA shows gas within the treated area (arrow). Right: T-1 weighted contrast-enhanced coronal MRI scan 2 months post RFA. Area without enhancement (arrow) shows devascularized necrosis of the treated lesion.

Figure 4. Palliation of Pelvic Metastasis Post RFA

Left: Contrast-enhanced computed tomography (CT) scan of painful metastatic ovarian carcinoma in the pelvis, causing dyspareunia, urinary frequency, and severe pain recalcitrant to conventional treatment. Middle: Unenhanced CT scan shows the RFA probes (arrow) in the tumor during treatment. Right: Enhanced CT scan 6 months post RFA shows interval shrinkage and loss of enhancement throughout tumor, except for enhancing nodule adjacent to the rectum (arrows).