Surgeon-performed ultrasound-guided fine-needle aspiration cytology of head and neck mass lesions: sampling adequacy and diagnostic accuracy.

BACKGROUND

Studies of surgeon-performed ultrasound-guided fine-needle aspiration cytology (US-FNAC) have been limited largely to thyroid nodules. This study evaluated the sampling adequacy and diagnostic accuracy of surgeon-performed US-FNAC for a large range of head and neck mass lesions, including lesions of the thyroid, salivary glands, and lymph nodes.

METHODS

The study included 617 cases of US-FNAC performed by a single surgeon between 2009 and 2013. Their medical histories and ultrasound (US) findings were retrospectively reviewed. Sample adequacy was analyzed according to the surgeon's experience, anatomic tumor location, and US tumor characteristics. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of FNAC were calculated after correlation with the surgical histopathologic results.

RESULTS

The overall adequacy rate for surgeon-performed US-FNAC was 91.9 % (567/617). Inadequate specimens were obtained from 9.7 % (29/282) of the thyroid glands, 6.1 % of the salivary glands (6/98), and 6.3 % (15/237) of the lymph nodes. The effect of the surgeon's experience plateaued (inadequate sampling rate, 6-8 %) after 100 US-FNAC procedures. Inadequate sampling was associated with tumor characteristics such as cystic change and rim calcification. Overall, US-FNAC showed a sensitivity of 88.2 %, a specificity of 98.2 %, a PPV of 98.5 %, an NPV of 85.7 %, and a diagnostic accuracy of 91.6 %.

CONCLUSION

With proper training and experience managing at least 100 US-FNAC cases, surgeons can ensure a low inadequate sampling rate and good diagnostic accuracy for a range of head and neck mass lesions.