THU0577 EFFICACY OF RADIOSYNOVIORTHESIS IN PIGMENTED VILLONODULAR SYNOVITIS OF THE KNEE
Authors: Zsolt Karoly Mangel, György Nagy, Margit Szentesi
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Pigmented villonodular synovitis (PVNS) is a rare disorder with the benign tumoral proliferation of the synovium. The surgical treatment of PVNS alone in most cases is unsatisfactory, because if a few cells have not been removed, the disease will recur.<sup>1</sup> Post-synovectomy adjuvant treatment with intra-articular injection of Yttrium-90 (<sup>90</sup>Y) or Holmium-166 (<sup>166</sup>Ho) yielded better results. The radiosynoviorthesis (RSO) is an effective way of treating the chronic synovitis, with this method we are eliminate the inflammation in 75 percent of the cases.<sup>2</sup> <h3>Objectives</h3> To study efficacy of radiosynoviorthesis after the surgical synovectomy in pigmented villonodular synovitis of the knee. <h3>Methods</h3> Between May 1986 and August 2018, 17 patients (seven men and ten women aged 14–68 years) with diffuse PVNS were treated. All patients had monoarticular arthritis of the knee with histologically proved PVNS. The patients underwent 33 operations, two patients had four surgical procedures, one patient underwent three surgeries, eight patients had two surgeries and six patients had one surgical procedure (Table 1.). The radiosynoviorthesis was performed according to the method accepted in the national protocol.Yttrium-citrate injectable suspension marked by 185 MBq 90Y-citrate injectable suspension, and 40 mg of 1 ml triamcinolone acetonide and 1 ml of lidocaine 1%.<sup>3</sup> Holmium-phytate injectable suspension marked by 600 MBq 166Ho-phytate injectable suspension, and 40 mg of 1 ml triamcinolone acetonide and 1 ml of lidocaine 1%.<sup>3</sup> Evaulation was based on the criteria as described by Müller, Rau and Schütte the score system was developed by the authors.<sup>4</sup> The circumference of joint-swelling, the joint function, the measure of flexio-contracture, pain in state of rest and load on a pain analogue scale 1-10, joint warmth, walking capacity, the numbers of joint-punctions after the treatment, whether operation was necessary or not after the treatment were examined. <h3>Results</h3> Mean follow-up time was 56 months (range from 4 to 144 months). All patients were followed up using clinical assesment. After the first injection excellent and good results were recorded in 41%. After the second radiosynoviorthesis thirteen patients (76%) showed excellent and good response (Table 2.). The mean functional evaluation score of 17 patients was 28 (range 16-34). Most of the ratings were excellent or good, in four cases moderate (24%). No complications were noticed after surgery or after the radiosynoviorthesis. <h3>Conclusion</h3> A combination of debulking surgery with radiosynoviorthesis of Yttrium or Holmium for diffuse PVNS of the knee joint is a reliable treatment method, with good results. <h3>References</h3> [1] Jaffe HL, Lichtenstein L, Sutro CJ (1941) Pigmented villonodular synovitis: bursitis and tenosynovitis. Arch Pathol. 31:731–765. [2] Jahangier ZN, Moolenburgh JD, Jacobs JWG, et al. The effect of radiation synovectomy in patients with persistent arthritis: A prospective study. Clin. and Exp. Rheumatol. 2001; 19:417-424. [3] EANM Procedure Guidelines for Radiosynovectomy, Eur J Nucl Med(2003) 30:BP12–BP16, Vol. 30, No. 3,March2003. [4] Rau R, Schütte H. Results of radiosynoviorthesis with yttrium 90 in chronic synovitis: a long-term prospective study. I. Total results and effect of local factors. Z Rheumatol. 1983; 42: 265-70. <h3>Disclosure of Interests</h3> None declared