NEW YORK (Reuters Health) - The results of a new study suggest that
silicone breast prostheses may increase the risk of developing a rare form of
lymphoma - cancer of the lymph system. However, the authors emphasize that
because anaplastic large T-cell lymphoma (ALCL) of the breast is so rare, the
absolute risk is still very low.
Dr. Daphne de Jong, from The Netherlands Cancer Institute, Amsterdam, and
colleagues evaluated the association between silicone implants and this cancer
after identifying two patients who had ALCL in the fibrous capsule surrounding
their silicone breast implants. Although similar cases had been reported in the
literature, no formal studies have examined the topic.
A search of a Dutch pathology database identified 11 women (average age of 40
years) who were diagnosed with ALCL of the breast from 1990 to 2006. Each
patient was matched by age and year of diagnosis to one or more women with other
types of lymphomas in the breast (the control group).
Five of the ALCL patients had received silicone implants in both breasts 1 to 23
years prior to diagnosis, the authors report in the Journal of the American
Medical Association for November 5th. In all five women, the implants were
placed for cosmetic reasons.
The most common lymphoma in the control group was diffuse large B-cell lymphoma,
followed by mucosa-associated lymphoid tissue-type lymphoma. Just 1 of the 35
control patients had a breast implant prior to their lymphoma diagnosis.
"The odds ratio for ALCL in the breast associated with silicone breast
prosthesis placed for cosmetic reasons was 18.2," the investigators calculate.
As noted, though, the absolute risk of ALCL with silicone breast implants is
exceedingly small. The authors calculate that just 0.1 to 0.3 cases per 100,000
women with implants would arise per year.
"These findings must be considered preliminary and hypothesis-generating and are
not strong enough to definitively conclude that breast implants predispose women
to non-Hodgkin lymphoma," Dr. Andrew M. Evens and Dr. Brian C.-H. Chiu, from
Northwestern University, Chicago, write in an accompanying editorial.
"However," they add, "given that silicone is immunogenic, further evaluation of
breast implant-related lymphoma is warranted, particularly by studies with
statistical power, sufficient follow-up, and information on other factors."
Source : JAMA 2008;300:2030-2035,2059-2061.
