WCCL Debate: Treating Poor Mycosis Fungoides Prognosis Early

I think the answer to this question is we’re not there yet, but we’re going there. We’re looking for markers that can confirm who’s going to progress or not, because a patient who will live for 20 years without harm, if you put him on a bone marrow transplantation, he can either die or have heavy consequences of this treatment.

Maarten H. Vermeer, MD, PhD, professor and chair of the Department of Dermatology at Leiden University Medical Center in Leiden, the Netherlands, and Jade Cury-Martins, MD, PhD, a dermatologist in the Department of Dermatology at the University of São Paulo Medical School in São Paulo, Brazil, debated whether patients with early-stage mycosis fungoides (MF) and poor prognostic features should be treated differently from the onset.

At the 6th World Congress of Cutaneous Lymphoma (WCCL), Vermeer and Cury-Martins took up the question in a debate — though both quickly acknowledged they agreed on most of it. The conventional approach to early-stage MF is skin-directed therapy first, escalating only on progression, specifically to spare patients the toxicity of systemic treatment in a disease that is often indolent. This first part of the discussion focused on where the staging system falls short and whether prognostic markers are yet ready to change frontline decisions.

Vermeer opened by framing the limits of current tools. Diagnosis and staging in early MF are reliable, but the IA/IB system does not fully capture who is at risk, and patients with patches alone tend to fare better than those with plaques. Beyond staging, clinicians choose among available therapies with no preferred order, guided by physician judgment, local resources, and patient preference.

The crux of the debate was whether additional high-risk features should change treatment from the outset, and both experts landed in a similar place. The trade-off is one of competing errors: withholding more aggressive therapy from a genuinely high-risk patient risks missing a window, while treating a patient who would never progress exposes them to unnecessary toxicity in a disease where overall prognosis is generally favorable and the absolute benefit to be gained is small.

Investigators are working to combine emerging prognostic factors into an indicator that could flag patients at greatest risk of progression. Cury-Martins contrasted the situation with hematologic malignancies, where a specific marker in acute leukemia can directly justify a different treatment, to underscore that cutaneous lymphoma lacks that predictive precision. Both speakers noted that modern options are more tolerable than the multiagent chemotherapy of the past — the real contrast now is systemic versus skin-directed therapy — but earlier use of newer agents still has not been shown to change long-term outcomes.

Vermeer added a conceptual caution that frames the entire debate: even a validated prognostic indicator establishes who is likely to progress, not that intervening earlier will alter the disease course — a distinction the experts agreed only a properly designed study can resolve.