The application of ultrasound in detecting lymph nodal recurrence in the treated neck of head and neck cancer patients

Abstract

Early detection of neck lymph node (LN) recurrence is paramount in improving the prognosis of treated head and neck cancer patients. Ultrasound (US) with US-guided fine needle aspiration (FNA) and core needle biopsy (CNB) have been shown to have great accuracy for LN diagnoses in the untreated neck. However, in the treated neck with fibrosis, their roles are not clarified. Here, we retrospectively review 153 treated head and neck cancer patients who had received US and US-guided FNA/CNB. In multivariate logistic regression analyses, size (short-axis diameter >0.8 cm) (odds ratio (OR) 4.19, P = 0.007), round shape (short/long axis ratio >0.5) (OR 3.44, P = 0.03), heterogeneous internal echo (OR 3.92, P = 0.009) and irregular margin (OR 7.32, P < 0.001) are effective US features in predicting recurrent LNs in the treated neck. However, hypoechogenicity (OR 2.38, P = 0.289) and chaotic/absent vascular pattern (OR 3.04, P = 0.33) are ineffective. US-guided FNA (sensitivity/specificity: 95.24%/97.92%) is effective in the treated neck, though with high non-diagnostic rate (29.69%). US-guided CNB (sensitivity/specificity: 84.62%/100%) is also effective, though with low negative predictive value (62.5%). Overall, US with US-guided FNA/CNB are still effective diagnostic tools for neck nodal recurrence surveillance.

Figure 1

All significant ultrasound features of malignant lymph nodes (LNs) in the treated neck of head and neck cancer patients: (a) Left level IV recurrent LN with irregular margin (interrupted margin) (arrow), malignant (b) Left level IIa recurrent LN with round shape (short/long axis ratio >0.5), malignant (c) Right level Ib recurrent LN with size >0.8 cm, short axis, malignant (d) Right level Ib recurrent LN with heterogeneous internal echo, malignant.

Figure 2

In comparison to the untreated neck, there are two ultrasound features of lymph nodes (hypoechogenicity and avascular pattern) that are more frequently noted in the treated neck: (a) Left level III benign LN in the untreated neck, isoechogenicity (equal to left sternocleidomastoid muscle (star) without fibrotic change) (b) Right level IV non-recurrent LN in the treated neck, hypoechogenicity (lower than right sternocleidomastoid muscle (star) with fibrotic change after previous neck dissection) (c) Left level Va recurrent LN in the treated neck, hypoechogenicity (lower than left sternocleidomastoid muscle (star) with fibrotic change after radiation) (d) Left level IIa benign LN in the untreated neck with typical linear hilum using a Doppler scan (e) Right level III non-recurrent LN in the treated neck, avascular pattern using a Doppler scan (f) Left level III recurrent LN in the treated neck, avascular pattern using a Doppler scan.

Figure 3

Pathologic pictures of fibrotic tissues in US-guided CNB samples in treated necks: (a) Left level IIa non-recurrent LN in the treated neck (benign fibro-adipose tissue with increased collagen deposition, hematoxylin and eosin stain, 200x) (b) Right level IV recurrent LN in the treated neck (malignant spindle cells in the fibrotic stroma, hematoxylin and eosin stain, 200x).