Secondary localized cutaneous amyloidosis.

Amyloidosis continues to be an intriguing yet poorly understood disease. The etiology remains obscure, and although the chemical composition of amyloid has been elucidated somewhat, there still remains a great gap in our knowledge as to its exact nature and the mechanism of its formation. Briggs 1 recently defined amyloidosis as a disease of unknown cause characterized by the accumulation of an amorphous, proteinaceous material in various organs and tissues of the body. Such a generalization encompasses all of the pertinent features of this entity. Although various classifications of amyloid disease are available in the medical literature, Calkins and Cohen 2 expressed the prevailing opinion in stating that the differentiation into types according to tissue distribution and staining characteristics of amyloid is somewhat artificial. There are so many instances of overlapping of these features that differentiation into primary and secondary types should depend upon the presence or absence of