To evaluate the application value and feasibility of negative pressure aspiration biopsy needle in the biopsy of complicated liver lesions.

Clinical data of 81 patients who underwent ultrasound-guided liver tumor ablation and biopsy in the Third Affiliated Hospital ofSun Yat-sen University from March 2022 to September 2022 were retrospectively analyzed. The informed consents of all patients were obtained and the local ethical committee approval was received. Among them, 66 patients were male and 15 female, aged from 30 to 73 years, with a median age of 58 years. Ultrasound-guided Sonopsy-C1 18 G negative pressure aspiration biopsy needle was used to obtain the samples from different angles through the coaxial needle for 1-4 times. Satisfactory tissues were obtained. The accumulated tissue length was >20 mm, fixed in 10% formalin solution, and transferred for pathological examination. Then, microwave or radiofrequency needle was utilized to ablate the lesions and cauterize the needle track through the coaxial needle to prevent the bleeding from needle track. According to the size and location characteristics of the lesions, all lesions were divided into the complicated group and non-complicated group. Baseline data and outcome indexes were compared between two groups. The length of tissues between two groups was compared by Wilcoxon signed rank-sum test. The incidence of complications was compared by Chi-square test or Fisher's exact test.

90 lesions were detected from 81 patients, including 59 cases and 64 lesions in the complicated group, and 24 cases and 26 lesions in the non-complicated group. In the complicated group, the distance from vital organs was 0 (0,2) mm, significantly less than 11 (9,15) mm in the non-complicated group (Z=-7.767, P<0.05). The success rate of biopsy and pathological diagnosis rate were 100% in two groups. No serious complications occurred in two groups. There were no significant differences in the maximum diameter of the lesions, adjacent organs of the lesions, the number of biopsy, the maximum length of the specimens and pathological results between two groups (P>0.05).

For small liver lesions or complicated lesions adjacent to vital sites, manual sampling with negative pressure aspiration biopsy needle under ultrasound guidance can obtain sufficient tissues for pathological diagnosis without increasing the number of sampling or sacrificing the risk of complications.