Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder (PCSM-TCLPD) is classified as a T-cell lymphoproliferative disorder rather than a true lymphoma in the 2016 World Health Organization (WHO) classification, given its indolent behavior. It can occur at any age, but it most commonly presents in the sixth and seventh decade of life, and it presents equally in men and women.

PCSM-TCLPD typically presents as a single papule, nodule, or plaque on the head, neck, or trunk. In around 25% of cases, more than one lesion is seen. Typically, this is a slow-growing lesion, but there have been cases reported where the lesion can enlarge rapidly. Disease is localized to the skin, follows a benign course, and carries an excellent prognosis.