Arotinoid-ethylester. Effectiveness in refractory cutaneous T-cell lymphoma

Five patients with refractory advanced cutaneous T-cell lymphoma (CTCL) (Stage IIB, two; Stage III, one; Stage IVA, two) and one patient with a refractory Stage IB CTCL (two females, four males, median age 58 years) were treated with a new polyaromatic retinoid, arotinoid-ethylester (Ro 13-6298), which has a much higher antiproliferative activity than other known retinoids. There was an objective clinical response in three of six cases [complete remission (CR) = 1, partial remission (PR) = 2]. One patient is in CR since 102 weeks currently. Mean duration of PR was 43 weeks. Two patients were withdrawn from treatment after 4 weeks because of disease progression. Two patients, one of them in PR, had to be retired from further treatment due to toxic side effects. Main side effects were mucocutaneous dryness, skin atrophy, and skin vulnerability. Skin biopsies were performed on four patients 4 weeks after the start of treatment. The epidermis and the subepidermal grenz zone were found to be clear of mononuclear clear cell infiltration in three patients. Although the number of patients is small, the results obtained suggest that arotinoid-ethylester offers a promising approach to the treatment of CTCL.