Does fluorescence diagnosis have a role in follow up of response to therapy in mycosis fungoides?

• Previously, few studies have used FD for evaluation of malignant potential in mycosis fungoides.
• Fluorescence diagnos is used to quantify tumor burden of MF-cells with all its immunophenotypes.
• Clinical improvement of skin lesions was found to correlate to changes in fluorescence diagnosis.
• Fluorescence diagnosis is an objective method to evaluate response of MF to therapy.

SummaryBackgroundMonitoring of tumor burden during mycosis fungoides (MF) treatment, is crucial to adjust therapy accordingly. This is usually achieved through combined by clinical assessment with histopathological and immunohistochemical evaluation.AimTo assess the validity of fluorescence diagnosis (FD) in the measurement of response to therapy in early MF, using in comparison flow cytometric technique of skin biopsies for CD4+/CD7− malignant T-cell count before and after therapy.Patients and MethodsTwenty-two patients of histologically proven early MF (stages Ia, Ib, IIa) were subjected to fluorescence diagnosis of their most affected skin lesion before and after 12 weeks of phototherapy with or without combination therapy. In comparison flow cytometric assessment of skin biopsies for CD4+/CD7− malignant T-cell count was evaluated before and after therapy from skin biopsy of the same lesion.ResultsAll tested MF lesions showed varying degrees of fluorescence by FD at week zero, with a mean accumulation factor (AF), which is the fluorescence ratio between the tumor tissue and normal skin, of 2.2. After 12 weeks of therapy, the mean AF showed significant reduction to 1.94 (p = 0.009). The percent of CD4+/CD7− cells dropped significantly after treatment (p = 0.029). No correlation between CD4+/CD7− cell counts and the mean AF could be deduced.ConclusionIn cases of mycosis fungoides, fluorescence diagnosis can represent an effective tool for evaluating the response to therapy. Changes in accumulation factor values can be used for follow-up of therapy in the same patient, but it should not be used as an absolute value.