[High frequency ultrasound combined with ultrasound-guided core needle biopsy for the diagnosis of primary thyroid lymphoma].

Objective: To investigate the sonographic features of primary thyroid lymphoma (PTL) and to evaluate the clinical significance of ultrasound-guided core needle biopsy (US-CNB) in PTL. Methods: A total of 24 patients with suspected PTL in Sir Run Run Shaw Hospital from January 2013 to June 2018 were analyzed retrospectively. All cases were confirmed by pathology, of them 23 patients received US-CNB and 1 patient chose operation without US-CNB, including 5 males and 19 females, aged from 39 to 75 years old. The effectiveness and safety of 23 patients with US-CNB were evaluated, and the sonographic features of 20 patients with PTL diagnosed by pathology were analyzed. Descriptive statistical methods were used in the study. Results: In the 23 patients with suspected PTL underwent US-CNB, 18 patients were diagnosed as PTL, 4 patients were respectively diagnosed as subacute thyroiditis, anaplastic carcinoma, Hashimoto's thyroiditis, and fibro thyroiditis, and the another patient was hard to diagnose by US-CNB and then was diagnosed as PTL by surgical biopsy. The success rate of US-CNB for diagnosis of PTL was 18/19, and no severe complications occurred in the patients with US-CNB. The other case was diagnosed as PTL by surgical biopsy without US-CNB. Sonographic features of 20 cases with PTL (18 cases diagnosed by US-CNB and 2 cases by surgery or surgery biopsy) were as follows: (1) Most nodules had irregular shapes and unsmooth margins; (2) Hypoechoic or markedly hypoechoic nodules with honeycombed or cord structures were observed in most cases; (3) Calcification was rare; (4) Multiple lesions were common; (5) Abundant intralesional vascularization was commonly observed; (6) Most cases had intensification of posterior acoustic enhancement; (7) Thyroid gland enlargement or with irregular shape; and (8) PTL often accompanied with lymph nodes enlargement in lateral neck or central region. Conclusion: PTL has certain sonographic features, with assistance of US-CNB, more accurate diagnosis of PTL can be obtained.