Treatment of bladder cancer, colon, liver, lung, breast, vagina, ovary, pancreas, kidney, stomach, gastrointestinal tract, prostate, head and neck, the peritoneal cavity, thyroid, bone, brain, blood and / or central nervous system, as well as / or use of Hsp90 inhibitors for the treatment of myelodysplastic syndrome, systemic mastocytosis, von Hippel-Lindau syndrome, psoriasis and / or multicentric Castlemans disease.膀胱、結腸、肝臓、肺、乳房、膣、卵巣、膵臓、腎臓、胃、消化管、前立腺、頭頸部、腹膜腔、甲状腺、骨、脳、中枢神経系および/または血液の癌の治療、ならびに/あるいは骨髄異形成症候群、全身性肥満細胞症、フォンヒッペルリンダウ症候群、多中心性キャッスルマン病および/または乾癬の治療のためのHsp90阻害剤の使用。