A patient presents with a small lesion in the lower lip that has been present for more than 5 months. Which biopsy technique is most appropriate?

Correct answer: C. Incisional biopsy

• A. INCORRECT. Exfoliative cytology (scraping cells from a surface lesion) is a screening tool, not a definitive diagnostic procedure. It cannot determine depth of invasion, margins, or tissue architecture — all critical for diagnosing persistent lip lesions. It may be used as an initial screen but is not appropriate as the primary biopsy technique for a lesion present >5 months.
• B. INCORRECT. Excisional biopsy (complete removal of the lesion with clear margins) is ideal for small lesions (<1–1.5 cm) where complete removal is both diagnostic and therapeutic. However, for a lesion present for >5 months in the lip — where carcinoma must be excluded — incisional biopsy first allows tissue diagnosis before committing to the extent of the surgery, especially if malignancy is suspected.
• C. CORRECT. Incisional biopsy (removal of a representative sample of tissue while leaving the bulk of the lesion in place) is the appropriate technique for a lip lesion present for >5 months. The chronicity (>5 months) raises concern for malignancy, and a representative tissue sample allows histopathological diagnosis to guide subsequent treatment planning. For lesions that may be carcinoma, incisional biopsy establishes the diagnosis before definitive surgical excision.
• D. INCORRECT. Fine needle aspiration (FNA) is most appropriate for deep-seated masses, lymph nodes, or salivary gland tumors. It is not the standard approach for accessible mucosal lip lesions where direct tissue biopsy can be performed.