Collagenase activity in relation to pathological state of cholesteatoma

Collagenase activities of the cholesteatoma epithelium, mastoid bone and skin from the bony external auditory meatus were investigated. The collagenase activity was measured directly in homogenates of tissues using the reconstituted radioactive collagen substrate. Twenty-one patients with cholesteatome were ranked in order of loss of the superstructure of the stapes, existence of eroded bony wall of the Fallopian canal and perilymphatic fistula. The collagenase activity of the cholesteatome epithelium was higher in the group with a high degree of bone destruction than in the group with a low degree of bone destruction. High collagenase activity may be a factor in the clinical aggressiveness of cholesteatoma.