Clinically benign, histologically malignant, recurrent cutaneous T-cell lymphoproliferative disorder characterized by an infiltration of large atypical cells surrounded by inflammatory cells. The atypical cells resemble REED-STERNBERG CELLS of HODGKIN DISEASE or the malignant cells of CUTANEOUS T-CELL LYMPHOMA. In some cases, lymphomatoid papulosis progresses to lymphomatous conditions including MYCOSIS FUNGOIDES; HODGKIN DISEASE; CUTANEOUS T-CELL LYMPHOMA; or ANAPLASTIC LARGE-CELL LYMPHOMA.

Variously described as a vasculopathy, endovasculitis, or occlusive arteriopathy, this condition occurs in a benign cutaneous form and a lethal multiorgan systemic variant. It is characterized by a narrowing and occlusion of the lumen of small to medium-sized blood vessels, leading to ischemia and infarction in the involved organ systems. The etiology and pathophysiology are unknown.

A member of the tumor necrosis factor receptor superfamily that may play a role in the regulation of NF-KAPPA B and APOPTOSIS. They are found on activated T-LYMPHOCYTES; B-LYMPHOCYTES; NEUTROPHILS; EOSINOPHILS; MAST CELLS and NK CELLS. Overexpression of CD30 antigen in hematopoietic malignancies make the antigen clinically useful as a biological tumor marker. Signaling of the receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.

A group of lymphomas exhibiting clonal expansion of malignant T-lymphocytes arrested at varying stages of differentiation as well as malignant infiltration of the skin. MYCOSIS FUNGOIDES; SEZARY SYNDROME; LYMPHOMATOID PAPULOSIS; and PRIMARY CUTANEOUS ANAPLASTIC LARGE CELL LYMPHOMA are the best characterized of these disorders.

A chronic, malignant T-cell lymphoma of the skin. In the late stages, the LYMPH NODES and viscera are affected.

A systemic, large-cell, non-Hodgkin, malignant lymphoma characterized by cells with pleomorphic appearance and expressing the CD30 ANTIGEN. These so-called "hallmark" cells have lobulated and indented nuclei. This lymphoma is often mistaken for metastatic carcinoma and MALIGNANT HISTIOCYTOSIS.

A group of dermatoses with distinct morphologic features. The primary lesion is most commonly a papule, usually erythematous, with a variable degree of scaling on the surface. Plaques form through the coalescing of primary lesions.

Anaplastic lymphoma of the skin which develops as a primary neoplasm expressing the CD30 ANTIGEN. It is characterized by solitary nodules or ulcerated tumors.

The use of ultraviolet electromagnetic radiation in the treatment of disease, usually of the skin. This is the part of the sun's spectrum that causes sunburn and tanning. Ultraviolet A, used in PUVA, is closer to visible light and less damaging than Ultraviolet B, which is ionizing.

A name originally applied to a group of skin diseases characterized by the formation of fine, branny scales, but now used only with a modifier. (Dorland, 27th ed)

'Skin diseases' is a broad term for various conditions affecting the skin, including inflammatory disorders, infections, benign and malignant tumors, congenital abnormalities, and degenerative diseases, which can cause symptoms such as rashes, discoloration, eruptions, lesions, itching, or pain.

Disorders characterized by proliferation of lymphoid tissue, general or unspecified.

Tumors or cancer of the SKIN.

Drugs used to treat or prevent skin disorders or for the routine care of skin.

A persistent progressive non-elevated red scaly or crusted plaque which is due to an intradermal carcinoma and is potentially malignant. Atypical squamous cells proliferate through the whole thickness of the epidermis. The lesions may occur anywhere on the skin surface or on mucosal surfaces. The cause most frequently found is trivalent arsenic compounds. Freezing, cauterization or diathermy coagulation is often effective. (From Rook et al., Textbook of Dermatology, 4th ed, pp2428-9)

A malignant disease characterized by progressive enlargement of the lymph nodes, spleen, and general lymphoid tissue. In the classical variant, giant usually multinucleate Hodgkin's and REED-STERNBERG CELLS are present; in the nodular lymphocyte predominant variant, lymphocytic and histiocytic cells are seen.

The ordered rearrangement of gene regions by DNA recombination such as that which occurs normally during development.