Histiocytosis is a rare disease that involves cells called hystiocytes. The disease can range from limited involvement that spontaneously goes away to progressive multiorgan involvement that can be chronic and debilitating. In some cases, the disease can be life-threatening. It is approximated that histiocytosis affects 1 in 200,000 children born each year in the United States. The disease us rare and not much is known securely about how to treat it. Because of its rarity, prospective studies are not possible.
In 2009, a guideline was published by the Hystiocytosis Society. It recommends an initial 6-week course of therapy with vinblastine and prednisone for all patients regardless of risk organ involvement. It is also recommended that all patients who have complete disease resolution
after 6-12 weeks of initial therapy continue with maintenance therapy. Maintenance therapy consists of pulses of vinblastine and prednisone every 3 weeks and daily continuous 6-mercaptopurine (6MP) for total treatment duration of 12 months. Currently, there is insufficient evidence to support an optimal course of treatment for use with patients suffering from severe progressive disease who do not respond to standard therapy. Recently, promising results have been reported for patients treated with a combined regimen of 2-chlorodeoxyadenosine (2-CdA, Cladribin, Leustatin) and cytarabine (Ara-C) (12); as well as stem cell transplantation after reduced intensity conditioning regimen (RIC-SCT). However, the results generated by both reports are based on limited observations and must be validated by the prospective clinical trials, which is, as we said, logistically very difficult to put together.
Read Professional version here.