A 28-year-old presents with a pearly white mass visible through an attic perforation. Biopsy shows stratified squamous epithelium with a fibrous matrix. The matrix of cholesteatoma is characterised by which cell type responsible for bone erosion?

• A Osteoblasts stimulated by prostaglandins
• B Macrophages secreting collagenase directly
• C Osteoclasts activated by cytokines (IL-1, TNF-alpha, EGF) from epithelial keratinocytes ✓
• D Neutrophils releasing elastase causing ossicular necrosis

Explanation

Cholesteatoma matrix keratinocytes secrete cytokines including interleukin-1, TNF-alpha, and epidermal growth factor. These stimulate osteoclast differentiation and activation, leading to bone resorption via increased RANKL expression. Additionally, matrix metalloproteinases from keratinocytes contribute to collagen degradation. This mechanism explains the characteristic erosion of the scutum, ossicles, and bony walls seen in cholesteatoma — it is NOT a simple pressure effect but an active enzymatic/immunological process.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.