Abstract
Purpose: :
to use an enzyme–linked immunosorbant assay to determine if patients with uveal melanomas at high risk of metastasis treated with proton beam irradiation followed by interferon–alfa–2a (3 MIU TIW for 2 years) develop antibodies against this cytokine.
Methods: :
Frozen serum samples from 13 patients with uveal melanoma who had been treated with proton beam irradiation were analyzed for antibodies against interferon–alfa–2a. Eleven of these patients had received adjunctive treatment with interferon–alfa–2a (median dose=921 MIU, 98% of theoretical dose; median duration of treatment=23 months) in an attempt to prolong survival. Two patients received proton beam irradiation but did not receive interferon–alfa–2a. Serum samples were obtained before treatment with interferon–alfa–2a and also 18–24 months into their treatment. These sera were analyzed using ELISA.
Results: :
Of the 11 patients who received adjuvant IFN therapy, 2 developed melanoma metastasis; metastasis occurred a median of 36 months after diagnosis. The 2 patients who underwent proton therapy alone did not develop metastatic disease; one died from another primary cancer at 52 months after study enrollment. None of the thirteen serial serum samples demonstrated antibody production against interferon–alfa–2a at baseline or at the 18 month or 24 month timepoint.
Conclusions: :
In this small sample of patients with uveal melanoma, adjuvant interferon–alfa–2a treatment after proton irradiation was not associated with the production of antibody against interferon–alfa–2a. Lack of IFN efficacy may be due to factors other than the development of neutralizing antibodies.
Keywords: melanoma • uvea • tumors