Early lesions are red with subtle scale or fine wrinkles. They persist for months with little peripheral extension and are often diagnosed as eczema.

Infiltration of the entire skin produces thickened red skin with or without scale. These features are subtle, not always clinically diagnostic, and may require a biopsy for diagnosis.

Pink to red, slightly scaly patches of early mycosis fungoides; may be present for months or years, and misdiagnosed as eczema. Biopsy can help differentiate these subtle changes of cutaneous T-cell lymphoma.

Tumors develop from pre-existing plaques or erythroderma. Tumors can vary in size; some become huge.