Immunohistochemical analysis is important for diagnosing hypopigmented MF because neoplastic cells in this condition often express CD8, a hallmark feature of hypopigmented MF.7 In contrast to classical MF, which is characterised by neoplastic CD4+ T cells, hypopigmented MF typically shows a predominance of CD8+ cells. The gene discussed is CD8A; the disease is mycosis fungoides.