Discussion
MF is characterized by malignant proliferation of T cells with
epidermotropism in the skin.1 The diagnosis of MF is
often delayed by many years from the initial appearance of skin lesions
due to its indolent course and diagnostic difficulties as in our
patient. In the early stages of disease, it can mimic common skin
conditions like chronic eczema, psoriasis and atopic
dermatitis.1,2
The factors predisposing for higher rates of certain malignancy in MF is
not known, however an inherent potential of disease itself or therapy
utilized for treatment could be the potential cause.3Viral infections, genetic factors, and environmental exposures
implicated in carcinogenesis might be the common mechanism linking the
onset of MF with increased risk for a second
malignancy.4 Furthermore, altered T-cell activation in
MF might contribute to develop secondary lymphoid malignancy, as it is
evident that a subset of highly immunosuppressive regulatory T cells
emerging from the infiltrating malignant T cells increases the risk of
severe infections and malignancy in MF as in our
case.3,4
Diagnosis is difficult especially in the early stages, but it is made
through clinical examination and is confirmed by a skin biopsy,
immunohistochemistry and staged appropriately. Histologically, early MF
are characterized by epidermotropism, atypical lymphocytes with
cerebriform nuclei, Pautrier’s microabscesses and basal alignment of
neoplastic lymphocytes as seen in our case. In immunohistochemistry, MF
cells are positive for CD2, CD3, CD4, CD5 and negative for CD20 as
reported in our case.3,5 Management is based on
disease stage and includes skin-directed therapies, systemic therapies
and allogenic stem cell transplantation.1,2
MF is a clinical diagnosis; however, is easily misdiagnosed at an early
stage due to its nonspecific clinical features and lack of awareness,
warranting a high index of clinical suspicion. MF should be suspected in
patients with underlying malignancies and patients with MF are at high
risk for developing secondary malignancies which should be screened for
and the other way around.