Evaluation: Fine Needle Aspiration Cytology, Ultrasound-Guided Core Biopsy and Open Biopsy Techniques

The optimum technique for biopsy assessment of the nature of a major salivary gland mass remains controversial. Fine needle aspiration cytology (FNAC) has been the traditional and popular choice, but sampling of cellular clusters is largely associated with high non-diagnostic and false-negative rates, even under optimised circumstances. Ultrasound-guided core biopsy (USCB) provides a core of tissue that allows preservation of tissue architecture and that can be histologically and immunohistochemically examined, thereby improving the chances of a meaningful diagnosis. Although relatively recently applied in the pre-operative investigation of salivary lesions, USCB shows higher levels of accuracy and reduced non-diagnostic rates when compared with FNAC, in addition to good patient tolerability. A degree of caution should, however, be exercised because of the potential for tumour seeding, and time delays inherent to histological processing are also unavoidable. Where available, USCB may be given preference as the biopsy technique of choice in major salivary gland diagnosis. In units where FNAC performs well, USCB can be utilised when FNAC is non-diagnostic or equivocal. Intra-operative frozen section collection is invasive but may offer a secondary option in cases of non-diagnostic FNAC and/or USCB or when USCB is not available.