Clinical Outcome after One Year Following Samarium-153 Particulate Hydroxyapatite Radiation Synovectomy

Abstract

The clinical outcome and tolerability following treatment with samarium-153 particulate hydroxyapatite was evaluated in patients with persistent rheumatoid knee synovitis. The clinical review of 18 patients treated with intra-articular samarium-153 particulate hydroxyapatite combined with triamcinolone hexacetonide who had failed to obtain more than 4 weeks symptom relief from a prior intra-articular glucocorticoid injection was undertaken. No unwanted effects from the treatment were observed. Symptom relief was maintained in 56% patients at 6 months and in 44% of patients at 12 months following treatment. Median duration of symptom relief was 9 months. There was a significantly higher mean baseline Ritchie Articular Index in patients relapsing within 3 months and a trend towards earlier relapse in patients with higher indices of disease activity at the time of treatment. There was a trend towards earlier relapse in patients with a poor range of knee flexion at baseline and with worse indices of intra-articular radiopharmaceutical distribution. Samarium-153 particulate hydroxyapatite knee synovectomy is well tolerated and may be an effective treatment for carefully selected patients with persistent rheumatoid knee synovitis.

Clinical Outcome after One Year Following Samarium-153 Particulate Hydroxyapatite Radiation Synovectomy

“…On the other hand, taking the ESR as a measure of general disease activity, a significant correlation was found between the favourable outcome and a low ESR (measured just before treatment). These findings are in agreement with the observations and conclusion in the Sm-153 PHYP study (1), that patient selection for radiation synovectomy treat ment of persistent synovitis should favour with drugcontrolled or inactive synovitis of most other joints. Do the authors think, that Sm-153 PHYP is a more suitable radiopharmaceutical than Y-90-colloids for treatment of chronic persistent knee synovitis?…”

“…Comparative efficacy can only be compared through large randomised controlled studies. As alluded to (1,2), the rationale underlying recommendations for joint-specific application of radiopharmaceuticals may be flawed for a number of reasons: the biological (cellular) target within chronic ally-inflamed synovium has not been defined and thus its distribution within the tissue cannot be predicted: consistent differences between synovial dimensions in different appendicular joints have not been described; the relative effect of intra-articular distribution of various radiopharmaceuticals within a joint cavity and uptake into synovial tissue in the context o f radionuclide half-life, dose rate and therapeutic ß " penetration and also radiopharmaceutical biological half-life, has never been elucidated.…”

“…I was interested to read the paper, on the clinical effect of sam arium -153 particulate hydroxyapatite (Sm-153 PHYP) in patients treated for persistent rheumatoid arthritis knee synovitis (1). Comparing with yttrium-90 (Y-90) colloids, the most commonly used radiopharm aceutical for radiation synovectomy, Sm-153 has a shorter half-life, respectively 2.7 and 1.9 days, a shorter maximum penetration in the soft tissue respectively 10.8 and 3.1 mm and it has in contrast with Y-90 a y decay.…”

Avaliação radiodosimétrica através do código MCNP-5 da radiosteoplastia em tumores ósseos nos membros

“…Esta escolha é atrativa considerando a emissão de raios gamas e X de baixa energia, sua baixa meia vida, e emissão de raios betas que permanecem no leito do tumor. Ambas as emissões betas, raios-gama e X contribuem com a dose no tumor [13,14,15]. A meia-vida que caracteriza o decaimento radioativo do nuclídeo samário-153 é de 46,3 horas; entretanto sua eliminação corpórea produz uma meia-vida biológica de 50,6 dias [16].…”

Nuclear Medicine in Musculoskeletal Disorders: Clinical Approach

“…These substances are phagocytized by synoviocytes localised in relation to the synovia and it creates a radiation source that can act locally and reduce inflammatory and proliferative elements (Colamussi et al, 2004;as cited in Gumpel et al, 1975). The availability of new radiopharmaceuticals, created by replacing the colloid vector with hydroxyapatite crystals, has allowed the main undesired effect of these substances (radiation to other organs such as drainage lymph nodes, liver, spleen and bone marrow, due to the passage of the radio compound from the articular cavity to the lymphatic and then to the blood flow systems) to be avoided (Clunie et al, 1996). In the absence of side effect, this technique of low cost may be useful, not only in the treatment of advanced stage and drug-resistant arthropathies, but also to manage pain and improve articular function in the first stages of rheumatoid arthritis (Colamussi et al, 2004;as cited in Uyeo et al, 1978).…”