<prompt> The commonest malignant tumour of the lids isBasal-cell carcinomaSquamous cell carcinomaAdenocarcinomaMelanocarcinoma  <response>: MALIGNANT TUMOURS Basal-cell carcinoma It is the commonest malignant tumour of the lids 90 usually seen in elderly people. It is locally malignant and involves most commonly lower lid 50 followed by medial canthus 25, upper lid 10-15 and outer canthus 5-10. Clinical features: It may present in four forms: Noduloulcerative basal cell carcinoma is the most common presentation. It stas as a small nodule which undergoes central ulceration with pearly rolled margins. The tumour grows by burrowing and destroying the tissues locally like a rodent and hence the name rodent ulcer. Ref:- A K KHURANA; pg num:-360 