6.4.5: 5. Fine Needle Aspiration Cytology (FNAC)
- Page ID
- 18326
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Limitations
- Because of 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 centers of cytology excellence) e.g. sacrificing marginal mandibular, hypoglossal, and lingual nerves, neck dissection, palliative vs. curative treatment
Indications
- Only selected salivary neoplasms require FNAC
- Potentially avoid surgery
- Suspected non-neoplastic disease
- Possibly a lymph node
- Elderly / infirm / refusing surgery
- Potentially modify surgery
- Malignancy: Elective neck dissection
- Suspected cervical lymph node metastases from salivary gland malignancy: therapeutic neck dissection
- Nerve weakness…. resect nerve involved by tumour
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