Interleukin 2 will be added to cycles 4-6 at days 6,8,10 (1 x 106 IU/m²/d s.c.) Participants will be premedicated with an intravenous antihistamine and ranitidine within approximately 30 minutes prior and during the infusion of the study agent Pain as an anticipated side effect is managed by a standard pain prophylaxis with Morphium hydrochloride Disease status will be evaluated after 3 and 6 courses and after 1 year