Background: Recent in vitro and in vivo studies hypothesize a synergistic effect of 13-cis-Retinoic Acid (13cRA) and recombinant alpha-IFN 2a (alpha-IFN) in the treatment of squamous cell carcinoma (SqCC).
Patients and methods: 35 patients with SqCC in several sites were treated with 13cRA (0.6-1 mg/kg/day) combined with alpha-IFN (6 x 10(6) I.U./day), continuously for 3 months.
Results: We observed an objective response in 41% of cases (13/32 evaluable patients) with 5 complete and 8 partial responses. Toxicity was mild and always rapidly reversible, with no haematological side effects.
Conclusions: These preliminary data confirm the feasibility and effectiveness of the combination of 13cRA and alpha-IFN in the therapy of SqCC, also in pre-treated patients, with acceptable toxicity and good compliance.