Atypical squamous metaplasia of bronchial epithelium. Note the heavily keratinized cytoplasm (orangeophilic), smudgy hyperchromatic nuclei, and relatively high nuclear to cytoplasmic (N:C) ratios. Background of mature squamous epithelium. These atypical cells, frequently observed in chronic bronchitis of smokers, need to be differentiated from a keratinizing squamous cell carcinoma.