A patient has had several basal cell carcinomas excised from the face. Which anatomical region carries the HIGHEST risk of recurrence?

Correct answer: B. The periorbital region, including the eyelid margin and inner canthus

• A. The forehead is intermediate-to-low risk, with adequate tissue for wide margins and reconstruction.
• B. CORRECT. The PERIORBITAL region — eyelid margins, inner canthus, nasolabial fold and periauricular skin — forms part of the classic 'H-ZONE' or mask area of the face, where basal cell carcinoma recurrence rates are highest. Two factors combine: embryonic FUSION PLANES allow deep, silent tumour extension along planes of least resistance, and the anatomical need to preserve function and cosmesis constrains the surgeon from taking wide margins. This is exactly the setting in which MOHS MICROGRAPHIC SURGERY is indicated, because it gives complete margin control while conserving tissue.
• C. The philtrum is within the central face and carries elevated risk, but the periorbital region and inner canthus are the higher-risk sites of the two.
• D. The lateral cheek is a low-risk site with generous surrounding tissue, permitting wide excision with straightforward closure.

Note: High-risk BCC features: H-zone location, diameter over 2 cm, ill-defined borders, recurrent lesion, aggressive histology (morpheaform, infiltrative, micronodular), perineural invasion, immunosuppression, prior radiotherapy to the site.