Rationale
The correct answer is D. Perform a punch or incisional biopsy to include the edge and base of the lesion.
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Clinical Suspicion: The presentation of a chronic, non-healing ulcer with a rolled (pearly) border is a classic sign of an advanced Nodular Basal Cell Carcinoma (BCC), often termed a “rodent ulcer”.
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Diagnostic Gold Standard: Before any definitive treatment can be planned, a histological diagnosis is mandatory. This is necessary to confirm the diagnosis, determine the exact BCC subtype (as some aggressive subtypes require different margins/treatments), and assess the depth of invasion.
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Biopsy Technique: For a solid, deep, or ulcerated lesion like this, a punch biopsy (which removes a full-thickness core of skin) or an incisional biopsy is the most appropriate method. It is crucial to sample the edge and base of the tumour to confirm the diagnosis and ensure sufficient depth for subtyping.
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Incorrect Options:
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A: Treating empirically with antibiotics is inappropriate for a chronic lesion highly suspicious for malignancy.
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B: Cryotherapy does not provide a histological sample, and its cure rate is lower for thick/ulcerated nodular lesions compared to thin, superficial ones.
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C: Observing a lesion with such classic malignant features would be a significant delay in diagnosis and is poor medical practice.
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E: Immediate radical excision without a confirmed diagnosis and subtype information is premature, although surgical excision will be the definitive treatment once histology is known. Furthermore, the surgical plan will depend on the histological subtype and depth (e.g., Mohs surgery for high-risk facial lesions).
Study – Skin cancers