This article is from November/December 2010 and may contain outdated material.
A chance discovery by a French pediatric dermatologist has paved a new path for treating periocular infantile hemangiomas.1 The new treatment is actually a half-century-old warhorse of a drug: the beta-blocker propranolol. Christine Léauté-Labrèze, MD, who practices at Children’s Hospital in Bordeaux, had given the drug to a four-month-old infant and almost immediately observed a diminishment of the color and volume of the baby’s hemangioma.
“It’s caught on like wildfire,” said David A. Plager, MD, director of pediatric ophthalmology at Indiana University in Indianapolis. “I can’t recall a medicine that was so rapidly accepted as an improvement over what we already had.” The old standards, intralesional or systemic steroids, as well as alpha interferon and the chemotherapeutic agent vincristine, are associated with significant side effects.
In the two years since the original French report, Dr. Plager has treated about 30 children with propranolol. “We haven’t used oral steroids in a hemangioma patient since we started using propranolol,” he said. “We love not using systemic steroids because patients don’t have to deal with their side effects. Those include effects on the immune system, endocrine system, diet, appetite . . . the list goes on and on.” He noted that in the case of intralesional injections, it can even include blindness from embolization of the medicine.
The culprit under pursuit. Hemangiomas are a common tumor of childhood that can occur anywhere on the body and can have both aesthetic and functional consequences. They appear during the first few months of life and typically stop growing by one year. Ophthalmologists get involved when lesions form around the eye, potentially impairing eyelid movement or visual acuity and putting a child at risk for amblyopia.
A large enough hemangioma can even cause the heart to pump harder to feed the blood vessels, said Tamara R. Fountain, MD, professor of ophthalmology at Rush University Medical Center in Chicago. “So it’s just thrilling to see a therapeutic effect from this drug, sometimes within 24 hours.” Dr. Fountain, an oculoplastic specialist, explained that surgery is sometimes not a satisfactory option. “It’s almost impossible to remove hemangiomas because the tangle of vessels has no distinct boundaries. The best surgical goal is to clear the visual axis and minimize induced mechanical astigmatism.”
A word of caution. Elaine C. Siegfried, MD, professor of pediatrics and dermatology at St. Louis University noted that the enthusiasm for propranolol resembles the optimism that greeted earlier hemangioma treatments and that was eventually dampened. “There was a lot of excitement about alpha interferon, for example, until reports of spastic diplegia appeared,” she said. Yet she is herself hopeful for propranolol, noting that a subset of hemangiomas is severe and life-threatening, justifying new treatments even if they carry risks. She said that, since the French discovery, 51 references have appeared in the literature and five clinical trials have begun recruiting patients. In fact, she is an investigator for one of the propranolol trials.
While Dr. Plager is cognizant of the side effects of propranolol—most notably hypoglycemia, bradycardia, bronchospasm and hypotension—he argued that they are rare and can be managed or avoided. He added that propranolol has a long history of safe use for conditions such as tachydysrhythmias and congestive heart failure.
The French connection. In fact, it was exactly cardiac complications resulting from steroid treatment for a hemangioma of the nasal pyramid that prompted Dr. Léauté-Labrèze to put her four-month-old patient on propranolol. Soon after, she observed a change in the color of the hemangioma and saw that it started to subside. She first thought the improvement was a coincidence. But three months later, she noticed a similar effect after administering propranolol to a child who developed tachycardia after treatment with corticotherapy. The hemangioma softened when palpated and a week later the mass was greatly diminished. Dr. Léauté-Labrèze then started using propranolol to treat other children with significant hemangiomas.
How Propranolol Might Work
Despite reports of dramatic shrinking of the hemangioma within a day or two of taking the medication, the response has not been uniform across patients. In a recent study, for which Dr. Plager was a coinvestigator, 17 babies between 3 weeks and 12 months of age were carefully ramped up on oral propranolol to 2 mg/kg/day for one to two weeks. Ten babies experienced excellent results, defined as greater than 50 percent reduction in size, and six had good results, meaning the hemangiomas decreased, though less than 50 percent. In the seventeenth baby, no further growth of the hemangioma occurred, and none of the 17 babies showed adverse effects.2 All of the babies’ families were satisfied with the outcomes.
“We don’t know why some respond better than others,” Dr. Plager said. For that matter, he said, the fundamental mechanism of action is not really known.
Dr. Léauté-Labrèze theorized that propranolol’s action as a vasoconstrictor may explain why the hemangioma softens following administration. She also thinks that by blocking beta-adrenergic receptors propranolol reduces the expression of VEGF and bFGF (basic fibroblast growth factor) and, in turn, the angiogenesis prompted by those factors.
It Takes a Team to Tame It
Propranolol requires a team approach, Dr. Fountain said. “These kids need to be monitored while on this systemic medicine. That includes blood pressure in young infants, and most ophthalmologists are not equipped in their offices to monitor that.”
Dr. Plager agreed. “There’s no reason why an ophthalmologist can’t prescribe propranolol.” But he recommended that the ophthalmologist comanage the patient with a pediatrician or other physician who can monitor blood glucose and pressure.
“There’s a window of opportunity to treat hemangiomas,” said Dr. Siegfried, who urged ophthalmologists to become familiar with propranolol. “We want to initiate treatment as early as possible to prevent growth.”
Those who are not comfortable prescribing propranolol might start the child on prednisone and then refer to someone familiar with the beta-blocker, she said. “But it is really important to treat them in a timely fashion.”
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Two Protocols So Far
“There are a couple of ways to put kids on propranolol,” Dr. Siegfried said. “We know you can’t start on a high dose.” Dr. Plager agreed. His research team developed a protocol for outpatient treatment with propranolol, while acknowledging that the pretreatment evaluation, the ideal therapeutic dose, the ideal treatment duration and knowing how to discontinue the drug all still need to be verified in large-scale studies.
Alert! Before starting any infant on propranolol, Dr. Plager warns clinicians to first establish that the infant doesn’t have PHACES, a hemangioma syndrome that is significantly more complicated than a localized lesion. PHACES is an acronym representing these criteria:
- Posterior fossa (brain malformations usually present at birth);
- Hemangioma usually covering a large area of the head or neck;
- Arterial lesions (abnormalities of vessels in the neck or head);
- Cardiac abnormalities/aortic coarctation;
- Eye abnormalities.
Children’s Hospital of Wisconsin maintains one of the most comprehensive sources of information on the management of PHACES.3
Protocol #1. PHACES complexity aside, Dr. Plager said, the protocol below is probably reflective of what many ophthalmologists are doing now:
- Before treatment—a complete ocular exam and electrocardiogram.
- If exam and EKG are normal, start patient on 25 percent of the full dose, slowly increasing to the full dose of 2 mg/kg/day, administered in three doses. Dose is not typically increased as the child grows and gains weight.
- Continue until complete resolution or regression of hemangioma—to the point of eliminating visual compromise—or until age 9 to 11 months.
- Wean over one- to two-week period.
- Monitor every two to three weeks initially; then every three to eight weeks.
Because propranolol predisposes the patient to hypoglycemia, Dr. Plager advised holding off treatment in the first week of life until the infant’s feeding habits are established, or any time when the infant’s oral intake is insufficient.
Protocol #2. Dr. Siegfried suggested a somewhat different protocol.4
- Do baseline echocardiography and 48-hour hospitalization or home nursing visits to monitor vital signs and blood glucose levels.
- Initial dose of 0.5 mg/kg/day, divided in two to three doses. For example, 0.16 mg/kg every 8 hours, or 0.25 mg/kg twice a day.
- Incrementally double the dose to a maximum daily dose of 3 mg/kg (1.5 mg/kg twice daily). The dose may be increased with weight gain.
- Gradually taper over two weeks.
Dr. Léauté-Labrèze specifed that propranolol is effective for infantile (capillary) hemangiomas, rather than venous malformations, cavernous hemangiomas or port-wine stains of Sturge-Weber syndrome.
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1 Léauté-Labrèze, C. et al. N Engl J Med 2008;358(24):2649–2651.
2 Haider K. M. et al. J AAPOS 2010;14(3):251–256.
3 Description adapted from the website of Children’s Hospital of Wisconsin:
www.chw.org/display/PPF/DocID/28483/router.asp.
4 Siegfried E. C. et al. N Engl J Med 2008;359:2846–2847.
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Dr. Léauté-Labrèze is the principal investigator of a propranolol study sponsored by Pierre Fabre Dermatology. The other physicians report no related interests.
Topical Timolol: Another Alternative?
Suqin Guo, MD, recently reported a case of successful treatment of infantile hemangioma with topical timolol solution.1 Dr. Guo, an assistant professor of ophthalmology and director of comprehensive ophthalmology at the University of Medicine & Dentistry of New Jersey Medical School in Newark, said she was inspired to try the topical beta blocker after learning of the French success with propranolol.
“It was an interesting case report,” Dr. Plager said of Dr. Guo’s experience. “If the hemangioma is on the surface, like a strawberry, topical beta-blockers may work well,” he said. But judging from experience with topical steroids, timolol may not penetrate the deep, golf-ball sized, three-dimensional structures that are most likely to threaten vision.
Dr. Guo, who then conducted a larger follow-up series of nine children with eyelid hemangioma, said topical timolol, 0.5 percent, significantly reduced the tumors. One exception—as Dr. Plager predicted—was a large, well-encapsulated eyelid hemangioma covered by normal skin. The timolol did not penetrate that tumor well.
But Dr. Guo said that timolol appears to be a sufficient remedy for the kind of eyelid hemangiomas that most ophthalmologists encounter. “It’s a very good alternative to propranolol for a localized, superficial, diffuse lesion where the skin is abnormal. In my experience with such cases, the outcome has been very good.”
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1 Guo, S. and N. Ni. Arch Ophthalmol 2010;128(2):255–256.
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