[Minimally-invasive regional treatment of a symptomatic ischial metastasis using radiofrequency ablation and osteoplasty].

History and Admission Findings: A 46-year-old woman presented with worsening, morphine-resistant pain during the previous 8 weeks in the right ischium which rendered her immobile. The patient refused further surgery, radiotherapy or chemotherapy, as she had been treated for ovarian cancer and recurring rectal carcinoma with peritoneal carcinomatosis for the last three years almost without interruption and experienced several complications. The pelvic region had radiotherapy up to 70,4 Gy.
Investigation: Scintigraphy of the bone showed enhancement in the right ischium. Conventional radiography demonstrated an irregular lesion with destruction of the corticalis 3 x 4 cm in size. Computed tomography revealed numerous microfractures and pseudo-arthritic changes. Needle biopsy confirmed a bone metastasis from the rectal carcinoma. Examination of radiation fields showed a high risk for radiation damage using conventional fractionation.
Treatment and Course: After achieving an interdisciplinary consensus the metastatic lesion of the patient under analgesia and sedation was thermo-ablated by using radiofrequency percutaneously under ct-control and filled with bone cement. 8 days later the patient was released from hospital pain-free and mobile. Her Karnofsky index rose from 30 % to 90 %. Morphine could be reduced to zero. No complications occurred. 9 month later, though newly appearing lung metastasis, the lesion of the ischium was still asymptomatic and stable and conventional radiography did not indicate local tumor progress or dislocated bone cement. The patient now agreed to further chemotherapy.
Conclusion: Palliative minimally invasive radiofrequency ablation with concurrent osteoplasty can be effective in individual cases giving a better quality of life and mobility. Benefits and risks should be carefully evaluated in studies examining quality of life, especially in patients without the options of surgical and radiotherapy.