Vitiligo vs. Melanoma

Metastatic melanoma is brutal. Once melanoma has recurred, there are really no good effective treatments to slow its spread through the body. People with metastatic melanoma have a life expectancy of only a few months.
Vitiligo is a poorly understood disease of the skin in which pigmented cells are attached by the immune system, leaving white, depigmented patches. This can by quite disfiguring, especially for dark complected people who may develop irregular white patches on their faces. Treatment usually consists of immune suppression. Interesting,y effective immune treatments for melanoma sometimes cause vitiligo in the melanoma patients.
I propose that the immune reponse in vitiligo patients be directly harnessed for the treatment of melanoma patients. The beauty of this is that the process need not be completely understood to be useful. Patients with severe vitiligo will donate plasma in the normal way, and from this will be made concentrated gamma globulin - possibly pooled from several (HIV negative, of course) vitiligo patients. Melanoma patients would then be periodically treated with this vitiligo globulin and followed to see if their disease lesions shrink. If this process turns out to be effective, the vitiligo globulin could be studied further to better understand and enhance the active principles.