Pediatric Clinics of North America - CIPERJ

368 RODRIGUEZ & HOOTS
infections and minimal pain, and does not require extensive rehabilitation.
Even though this procedure may not halt joint degeneration, it may effectively
reduce the frequency of joint bleeding along with a reduction in arthropathic
pain.
Radioactive synovectomy (RS) using P 32 has been used for chronic synovitis
in the United States since 1988. Initial comprehensive review of its use
suggested that this technique was efficient, safe, and not associated with malignancies
[25]. Subsequently, however, two cases of acute lymphoblastic
leukemia (ALL) after RS were reported in children who had hemophilia.
The first patient was a 9-year-old boy who had severe hemophilia A who developed
pre–B-cell ALL. The second was a 14-year-old boy who had severe
hemophilia A who developed T-cell ALL. Both patients developed their
ALL less than 1 year after treatment with RS [26], which raises the question
as to whether or not this may be too early for radiation-induced malignancy.
Both patients had a history of exaggerated immunologic response or autoimmune
disease.
There have been no further reports of cancer after RS in hemophilia or
rheumatoid arthritis in the United States. Data from a retrospective, longterm,
Canadian study evaluating the incidence of cancer in more than
2400 patients who had chronic synovitis from multiple diseases, including
rheumatoid arthritis and hemophilia, and who underwent RS were presented
at World Federation of Hemophilia (Georges Rivard, MD, Montreal,
Canada, unpublished data, 2007). In this study, Infante-Rivard and
colleagues [27] compared the incidence rates of cancer in a cohort of patients
treated with RS to the incidence rates of cancer in the general Quebec population,
as documented in the Quebec Province Cancer Registry. The majority
of the patients (80%) received one or two treatments using radioactive
isotopes, whereas the remaining underwent three or more procedures.
Most patients received yttrium 90 (70%) whereas close to 30% of the patients
received P 32 . Data analysis using a Cox regression model showed no evidence
of increased risk for cancer with the use of RS [27].
Currently, the use of RS is based on defined risks versus benefits. Therefore,
this approach may be recommended for patients who have no known
risk factors for malignancy who have developed a target joint and continue
to present recurrent hemarthrosis despite prophylactic therapy or in whom
prophylaxis is not an option. Nevertheless, informed consent should describe
the risks (discussed previously) clearly to parents and, when applicable,
to patients.
Current challenges in hemophilia management
Inhibitor development
There is no question that the development of inhibitory antibodies in hemophilia
is one of the most challenging aspects of current management. The