The Histological Spectrum of Early Mycosis Fungoides: A Study of 58 Saudi Arab patients.

OBJECTIVES The histopathological diagnosis of Mycosis Fungoides (MF) is challenging in its early stages and can easily be confused with inflammatory dermatoses. This study aims to; (i) assess the frequency and significance of different histopathological parameters in early MF, seen in Saudi patients, and (ii) to study the utility of these parameters in differentiating between early MF and inflammatory dermatoses. METHODS This is a five years study of 66 skin biopsies generated from 58 patients with clinically suspicious MF lesions or early patch stage MF. These cases were retrieved from the archives of the Department of Pathology, King Khalid University Hospital, Riyadh from the year 2002 to 2006. Histological criteria were assessed and graded semi-quantitatively on a four-point scale by a dermatopathologist and two pathologists independently. RESULTS The histological parameters suggesting the diagnosis in early stages MF include epidermotropism, dermal fibrosis, Pautrier's micro abscesses, Basal alignment of neoplastic lymphocytes, hyperconvoluted dermal and epidermal lymphocytes and grandiosity sign (size of lymphocytes becoming larger as they migrate towards granular layer of epidermis). These parameters on univariate analysis achieved statistical significance (p<0.05) in differentiating MF from non-MF cases. In addition, hyperconvoluted dermal and epidermal lymphocytes proved to be highly reliable with high specificity and sensitivity. CONCLUSION The histopathological diagnosis of early MF lesions and their discrimination from inflammatory simulators can be achieved by carefully observing the hyperconvoluted dermal and epidermal lymphocytes along with the constellation of the other parameters.