Ultrasound-guided, vacuum-assisted biopsy in evaluation of breast lesions

Aim. Evaluation of the efficacy of ultrasound-guided vacuum-assisted biopsy for the verification of breast lesions. Introduction. Ultrasound breast examination is a noninvasive method of breast imaging. It is adjunct to mammography and physical examination and, in women under 30 years of age, pregnant and lactating, it is the basic examination used for the detection and diagnosing of breast diseases. It allows also to obtain cells or tissue samples with such minimally invasive techniques as fine-needle biopsy, core needle biopsy or vacuum-assisted biopsy. Material and methods. The study group consisted of 138 women, aged from 20 to 76 years, who underwent ultrasound guided vacuum-assisted biopsy between March and December 2006. Because double lesions were diagnosed in 6 patients, this resulted in 144 performed procedures. Each patient underwent ultrasound examination, performed with a 10-12 MHz transducer. Biopsies were guided by a 12 MHz transducer and performed with the Mammotome System using an 11G or an 8G needle, depending upon the size and site of the lesion. Obtained data were compared using the Chi-square test; p values of less than 0.05 were considered indicative of a significant difference. Results. The average size of the biopted lesions was estimated as 11±3,8 mm (range: 4-30 mm). However, lesions described by radiologists as apparently suspicious were not qualified for the vacuum-assisted biopsy, in the tested material 4 lesions appeared to be carcinomas (3 were invasive breast carcinomas and 1 was ductal carcinoma in situ). When compared with other changes, these lesions were most frequently equivocal (3 vs 1 determined as benign, p=0.014). There was no statistically significant difference in echogenicity (3 hypoechoic vs 1 with mixed echogenicity) nor in the shape (1 oval change, 2 lobulated and 1 irregular). Pathological examination revealed 86 cases of fibroadenoma within the tested material. Those lesions were mostly benign (77 vs 9 equivocal changes, p=0.004), all of them were circumscribed, and statistically more often oval than lobulated in shape (75 vs 11; p=0.004), and also more frequently those lesions were hypoechoic (78 vs 8 with mixed echogenicity; p=0.0048). The other changes were divided into three groups: proliferating (in 47 samples: hyperplasia non atypica and adenosis), involuting (in 79 samples: fibrosclerosis, fibrosism atrophy, cysts and microcysts, fibrocystic disease and benign mammary dysplasia) and inflammatory lesions (in 5 samples). Conclusions. 1. Any mass located in the breast that is visible in ultrasound examination and is not a typical benign lesion must be verified. 2. Although vacuum-assisted biopsy is considered to be a good method for the assessment of equivocal changes, its limitations are high costs and, under Polish conditions, availability. (author)