6.3.5: 5. Fine Needle Aspiration Cytology (FNAC)
- Page ID
- 18311
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- Because of the highly complex and varied histology of salivary tumours, FNAC has limited accuracy, even in expert hands
- Benign vs malignant: 79%
- Precise histological type: 30%
- Cannot distinguish between high and low-grade mucoepidermoid carcinoma
- Consequently be cautious about making key surgical and radiotherapy decisions based on cytology alone (especially outside cytology centers of excellence) e.g. partial vs total parotidectomy, facial nerve resection, neck dissection, palliative vs curative treatment
Indications
- Only selected salivary neoplasms require FNAC
- Potentially avoid surgery
- Suspected non-neoplastic disease (e.g. HIV lymphoepithelial cyst, TB, benign cyst, lipoma)
- Suspected lymphoma
- Elderly / infirm / refusing surgery
- FNAC indicating Warthin’s tumour
- Potentially modify surgery
- Suspected lymphoma….core biopsy / incision biopsy
- Facial nerve weakness…. resect nerve involved by tumour
- Metastatic skin / conjunctival SCC or melanoma….superficial/total parotidectomy with elective/therapeutic neck dissection
- Tumour of parapharyngeal space….may determine surgical approach
- Suspected cervical lymph node metastases from salivary gland malignancy
Technique: FNAC can be done as an office procedure by the surgeon….Ultrasound guidance is rarely required https://onlinelibrary.wiley.com/doi/pdf/10.1111/1744-1633.12315