Why is simple enucleation of a pleomorphic adenoma of the parotid gland avoided in favour of formal parotidectomy with clear margins?

• A The tumour is always multicentric within the gland
• B Enucleation carries a high risk of immediate facial nerve palsy
• C The tumour lacks a true capsule and may have microscopic pseudopodial extensions ✓
• D Enucleation converts the benign tumour into a malignant one

Explanation

Pleomorphic adenoma has an incomplete, irregular capsule and can send microscopic pseudopodial projections into surrounding parotid tissue. Enucleation shells out along the false capsule and leaves these extensions behind, producing local recurrence rates far higher than those after formal superficial parotidectomy. The facial nerve is actually more endangered during reoperation for recurrence than during a properly planned primary procedure, which undermines distractor B.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.