This category is the second most frequent group of cutaneous T-cell lymphomas, corresponding to approximately 30% of the cases.1,4,6

A rare CD8+ cytotoxic αβ T-cell lymphoma, with involvement restricted to subcutaneous tissue,3 is associated with autoimmune diseases in 20% of the cases. It has a good prognosis, with neoplastic cells surrounding individual adipocytes. Positive gamma-delta cases should be excluded from this category.1,3,4,6 The absence of plasma cells and clusters of CD123-positive plasmacytoid dendritic cells aid in the differentiation of lupus panniculitis.7

It is defined as a clonal proliferation of mature and activated gamma-delta T cells expressing cytotoxic markers. Clinically, it is characterized by infiltrated plaques on legs, trunk and arms, usually in elderly people.9 In 60% of cases, erosion or necrosis occurs. Histologically, the disease is variable and can affect the epidermis, dermis and subcutaneous tissues by medium to large cell infiltrates with frequent angioinvasion and necrosis. LyP and MF cases can express gamma-delta receptors; however, these cases should continue to be diagnosed as LyP and MF. It has a poor prognosis.1,4,6 and subcutaneous involvement is an indicator of worse prognosis.1,9 The estimated 5-year survival is 19.9%.9

Provisional entity characterized by epidermotropic CD8+ T-cell lymphoma that demonstrates aggressive clinical behavior. The cells vary in size from small to large. Epidermotropism can be intense or even localized. Ulceration, necrosis, adnexal destruction and blister formation are common. When there is CD30 expression, the histopathological and immunohistochemical profile is indistinguishable from LyP type D; differentiation is based on the clinical history.1 It presents an estimated 5-year survival of 0%,3 which is not related to cell morphology (small versus large cells) nor to the presence of localized or diffuse disease.1

A rare clonal cutaneous infiltration of CD8-positive medium-sized cytotoxic T lymphocytes. It involves the acral skin, with ears being the most common site. It usually does not affect the epidermis, presents neither mitotic figures nor necrosis, and has a good prognosis.1,3

Previously called “primary cutaneous CD4+ small/medium T-cell lymphoma”, it was renamed “lymphoproliferative disorder” because it is a localized neoplasm with a certain resemblance to clonal proliferations secondary to medication use. Characterized by small- to medium-sized atypical CD4+ T cells, it usually appears as a single nodular lesion or plaque on the head and neck. This diagnosis requires that the hypothesis of MF be excluded, emphasizing that a small proportion of large and pleomorphic cells (<30%) can be identified. The prognosis is good, depending on whether it is a type of lymphoma, a precursor lesion, a totally benign lesion or a pseudolymphoma.1,3

Hydroa vacciniforme-like lymphoma has started to be considered a lymphoproliferative disorder due to its clinical presentation and its relation to active Epstein-Barr virus infection. It is a chronic lesion occurring in childhood and is associated with a risk of developing systemic lymphoma. It should be classified into two types: the classic self-limited type, characterized by vesicles in sun-exposed areas and a benign course; and the severe type, with extensive cutaneous involvement and systemic manifestations such

as fever, hepatomegaly and lymphocytosis in peripheral blood.3 There is no morphological or clinical basis capable of predicting biological behavior.1