Background: Mycosis fungoides (MF), the commonest primary cutaneous T-cell lymphoma, has classic and variant types which include hypopigmented MF (HMF). Previous studies have identified distinct clinicopathological profiles in HMF. This study aims to objectively compare the clinicopathological features of HMF with non-HMF lesions in order to characterize salient features of HMF. Methods: This cross-sectional, retrospective study analyzed biopsy specimens of 87 patients with MF. HMF and non-HMF groups were compared using clinical data, immunophenotypic features and scores given for six histopathological features: dermal infiltrate, basilar and superficially extending epidermotropism, Pautrier microabscesses and dermal and epidermotropic lymphocytic atypia. Results: Seventy-six patients had HMF. Presentation in females (59.21%; p = .04) and patch stage (88.16%; p = .01) in HMF were significant, and HMF presented at a younger mean age when compared to non-HMF. Both groups had equal intensity of epidermotropism, with HMF showing milder dermal infiltrates and significantly less dermal atypia. Pautrier microabscesses were significantly commoner in non-HMF (LR 10.76; p < .01). 94.74% of HMF were CD4−/CD8+. Conclusion: HMF presents at a lower age and earlier stage with female predominance compared to non-HMF. Because of milder dermal infiltrates, less dermal atypia, and Pautrier microabscesses, the diagnosis of HMF requires correlation with clinical features and careful assessment of epidermotropic cells. K E Y W O R D S hypopigmented mycosis fungoides, cutaneous lymphoma, CD8-positive mycosis fungoides 1 | INTRODUCTION Mycosis fungoides (MF) is the commonest type of primary cutaneous T-cell lymphoma (CTCL), with an annual incidence of 0.3 to 0.5/100,000 population. 1,2 A lower incidence is reported in Asians and Chinese. 2 MF is defined according to its classical type, and several pathological 3,4 and clinical 5,6 variants have been described. Hypopigmented MF (HMF) is a rare clinical variant, with most cases

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