We respectfully disagree with Di Lernia's comment that patients with pilar MF, F-MF, or folliculotropic cutaneous T-cell lymphoma (CTCL) “should always be considered to have tumor-stage disease.”
We are familiar with the 2002 article by van Doorn et al1 that describes 51 patients with F-MF who had disease-specific survival rates of 68% at 5 years and 26% at 10 years and posits that the prognosis for F-MF is similar to that for epidermotropic tumor-stage disease.1 However, Di Lernia did not cite 2 more recent reports that give much better survival rates for F-MF. In a 2005 report,2 the European Organization for Research on the Treatment of Cancer classifies F-MF as a distinct subgroup. The 5-year survival rate of 86 patients with F-MF is reported to be 80%, while that of 800 patients with classic MF is 88%.2 A 2008 report by Gerami et al3 comparing a United States group of 43 patients with F-MF to age- and stage-matched patients with epidermotropic MF found that those with early F-MF (up to and including stage IIA) had a 10-year survival of 82% and a 15-year survival rate of 41%. The 43 control patients who had epidermotropic MF had a 91% survival rate at both 10 and 15 years. However, patients with later-stage F-MF (stage IIB or higher) had outcomes similar to those with conventional epidermotropic MF of a similar stage. And the 10-year progression-free survival rate was 25% in the patients with stage IIB or higher F-MF compared with 8% in the epidermotropic MF group. While the authors conclude that F-MF is a more aggressive variant of CTCL, especially in the early stages, there was no evidence of worse prognosis in stage IIB or more advanced disease.
Worobec SM. Efalizumab and Progression of Undiagnosed Follicular Mycosis Fungoides—Reply. Arch Dermatol. 2009;145(7):844. doi:10.1001/archdermatol.2009.133