T-Cell Lymphoma

T-cell lymphoma is a type of non-Hodgkin lymphoma that begins in T lymphocytes, white blood cells that help the immune system fight infection. There are many subtypes. Some are aggressive and affect lymph nodes and organs; others develop slowly.

The most common form of cutaneous T-cell lymphoma (CTCL) is mycosis fungoides, which shows up in the skin. The National Cancer Institute describes mycosis fungoides and Sézary syndrome as diseases in which lymphocytes become malignant and affect the skin. Early mycosis fungoides can look like eczema or psoriasis, with red, scaly patches or plaques, and it is often misdiagnosed for years. Diagnosis usually requires a skin biopsy, sometimes more than one.

That overlap with eczema is why CTCL is at the center of lawsuits involving Dupixent (dupilumab), a biologic drug widely prescribed for atopic dermatitis. Plaintiffs allege that the drug was associated with CTCL or that it masked or accelerated an underlying lymphoma, and that the warnings were inadequate. These are allegations, the manufacturers dispute them, and whether the drug causes or unmasks CTCL is an open scientific and legal question.

If you took Dupixent and were later diagnosed with CTCL, the key records are prescription history, dermatology notes, and biopsy and pathology reports showing when the lymphoma was identified. Do not stop a prescribed medicine without talking to your doctor. See our Dupixent lawsuit page and our term page on non-Hodgkin lymphoma.