Skin cancer biopsy question? how deep is it?

Variable: That all depends on they type of biopsy. A shave is more superficial. A punch goes into the more superficial fat layer. Excisional biopsies can go much deeper, into the subcutaneous fat. The type of biopsy will depend on what diagnosis is being considered. Your doctor should discuss this all with you ahead of time.

Just deep enough!: Sorry to be a smart ass but the depth of the biopsy varies with the kind of skin cancer, but rarely goes deeper than the thickness of the skin. The area will be numbed, so, fortunately, it rarely matters to the patient how deep the biopsy extends. Biopsies of shallow lesions are usually shavings of a partial thickness of skin; deeper lesions often are punched, taking a small full-thickness piece.