Stereotactic Core-Needle Biopsy of Non-Mass Calcifications: Outcome and Accuracy at Long-Term Follow-Up

Objective

To determine, by means of long-term follow-up evaluation, the outcome and accuracy of stereotactic core-needle biopsy (SCNB) of non-mass calcifications observed at mammography, and to analyze the factors contributing to false-negative findings.

Materials and Methods

Using a 14-gauge needle, SCNB was performed in cases involving 271 non-mass calcified lesions observed at mammography in 267 patients aged 23-72 (mean, 47) years. We compared the SCNB results with those of long-term follow-up which included surgery, mammography performed for at least six months, and reference to Korean Cancer Registry listings. We investigated the retrieval rate for calcifications observed at specimen mammography and histologic evaluation, and determined the incidence rate of cancer, sensitivity, and the underestimation rate for SCNB. False-negative cases were evaluated in terms of their mammographic findings, the effect of the operators'' experience, and the retrieval rate for calcifications.

Results

For specimen mammography and histologic evaluation of SCNB, the retrieval rate for calcifications was, respectively, 84% and 77%. At SCNB, 54 of 271 lesions (19.9%) were malignant [carcinoma in situ, 45/54 (83%)], 16 were borderline, and 201 were benign. SCNB showed that the incidence of cancer was 5.0% (6/120) in the benign mammographic category and 31.8% (48/151) in the malignant category. The findings revealed by immediate surgery and by long-term follow-up showed, respectively, that the sensitivity of SCNB was 90% and 82%. For borderline lesions, the underestimation rate was 10%. For false-negative cases, which were more frequent among the first ten cases we studied (p = 0.01), the most frequent mammographic finding was clustered amorphous calcifications. For true-negative and false-negative cases, the retrieval rate for calcifications was similar at specimen mammography (83% and 67%, respectively; p = 0.14) and histologic evaluation (79% and 75%, respectively; p = 0.47).

Conclusion

In this study group, most diagnosed cancers were in-situ lesions, and long-term follow-up showed that the sensitivity of SCNB was 82%. False-negative findings were frequent during the operators'' learning period.     

Ductal carcinoma in situ diagnosed with stereotactic core needle biopsy: can invasion be predicted?

PURPOSE: To determine whether mammographic or histologic features can be used to predict which cases diagnosed as ductal carcinoma in situ (DCIS) without invasion by means of stereotactic core needle biopsy (SCNB) will have invasive disease at surgery. MATERIALS AND METHODS: From July 1992 to March 1999, DCIS without invasion was diagnosed by means of SCNB in 59 patients. Seventeen (29%) were found to have invasive disease after surgery. The underestimation rate for SCNB was compared with that obtained by means of open surgical biopsy. Mammographic and histologic features of cases with and those without invasion were compared. RESULTS: All patients had calcifications on mammograms. There was no significant difference (P: =.26) between the underestimation rate for SCNB with the 11-gauge vacuum-assisted device and that for open surgical biopsy. No statistically significant differences between cases with and those without invasion were seen in patient age, mean number of core specimens, level of suspicion, size of lesion, distribution and morphology of the calcifications, presence of an associated mass or density, subtype of DCIS, nuclear grade, or presence of necrosis or desmoplasia. CONCLUSION: Mammographic and histologic features cannot be used reliably to predict cases that are underestimated with SCNB. However, SCNB with the 11-gauge vacuum-assisted device was as reliable as open surgical biopsy for diagnosing DCIS without invasion.     

Lesion miss rates and false-negative rates for 1115 consecutive cases of stereotactically guided needle-localized open breast biopsy with long-term follow-up

PURPOSE: To retrospectively determine the lesion miss rate and false-negative rate of needle-localized open breast biopsy (NLOBB) with stereotactic guidance in a large study population. MATERIALS AND METHODS: The ethical review board approved the study; the need for informed consent was waived. A total of 1115 stereotactic NLOBBs performed in 1068 women aged 22-90 years (mean age, 54 years) were tracked to determine outcomes. In cases of malignancy, NLOBB was considered to be diagnostically successful. The mammographic outcomes in all patients with benign results at NLOBB were tracked for at least 2 years. Cases without such mammographic follow-up were cross-referenced with a tumor registry after at least 54 months. The lesion miss rate was based on all malignant lesions and all lesions with long-term mammographic follow-up. Results from all 1115 NLOBBs were used to report the false-negative rate. RESULTS: Of 1115 NLOBBs, 472 (42%) had malignant results. Mammographic follow-up data were available for 535 (83%) of 643 NLOBBs with benign results. Mammographic follow-up revealed 11 lesions that were missed with NLOBB, of which five were malignant and six benign. Thus, the lesion miss rate with NLOBB was 1.1% (11/[472 + 535]). Among the 643 cases, in 108 of them without mammographic follow-up (17%), cross-referencing with a tumor registry did not reveal missed cases of breast carcinoma. The false-negative rate was therefore 1.0% (5/[472 + 5]). CONCLUSION: On the basis of the results of long-term follow-up, the authors noted a lesion miss rate of 1.1% and a false-negative rate of 1.0%, which indicate that NLOBB with stereotactic guidance is an accurate method for diagnosing breast lesions.     

Stereotactic, automated, large-core needle biopsy of nonpalpable breast lesions: false-negative and histologic underestimation rates after long-term follow-up

PURPOSE: To determine the rate and causes of false-negative findings and histologic underestimates at stereotactic biopsy of nonpalpable breast lesions. MATERIALS AND METHODS: Stereotactic, 14-gauge, automated, large-core needle biopsy (LCNB) was performed in 483 consecutive nonpalpable breast lesions. Excision was advised for the 143 carcinomas, 25 atypical ductal hyperplasia (ADH) lesions, and five radial scars. Mammographic follow-up was advised for the benign lesions without a repeat biopsy. RESULTS: Of the 310 benign lesions, 259 underwent mammographic follow-up at 6-85 months (median, 55 months) without repeat biopsy, 48 underwent repeat biopsy and three were lost to follow-up. On the basis of the histologic diagnosis of carcinoma at surgical biopsy, diagnosis with LCNB was not correct (i.e., disease was underestimated at histologic examination) in 14 (58%) of 24 ADH lesions and two (40%) of five radial scars. Two (1.2%) of 161 lesions with a final diagnosis of carcinoma were benign at LCNB but malignant at repeat biopsy (i.e., false-negative findings at LCNB). Repeat biopsy was prompted by mammographic progression at 6 and 18 months after LCNB. CONCLUSION: The false-negative rate with LCNB was 1.2% in this study and 4.0% in the literature. The presence of carcinoma in ADH and radial scar lesions was often underestimated.     

Palpable breast thickening: role of mammography and US in cancer detection

PURPOSE: To determine the frequency of breast carcinoma and ascertain the diagnostic yield of mammography and breast ultrasonography (US) in the detection of breast carcinoma in women with palpable breast thickening. MATERIALS AND METHODS: One hundred twenty-three consecutive cases of breast thickening (103 patients) during a 1-year period were reviewed. Experienced breast examiners prospectively identified patients with breast thickening. Results of diagnostic mammographic work-up, breast US, breast biopsy, and clinical follow-up were retrospectively reviewed. RESULTS: Six (5%) of 123 cases had a diagnosis of breast carcinoma; five (83%) of the six had invasive carcinoma. Mammography was performed in all cases, US in 77 (63%) cases. Mammographic sensitivity for invasive cancer detection was 60% (three of five cases), specificity was 94% (102 of 108 cases), and negative predictive value was 97% (102 of 105 cases). Sensitivity of US alone was 100% (two of two cases), specificity was 96% (65 of 68 cases), and negative predictive value was 100% (65 of 65 cases). The combined negative predictive value of mammography and US was 100%. Patients with prior biopsies at the site of palpable thickening accounted for most false-negative mammograms. Median time to initiate follow-up of patients in whom biopsy was not performed was 14 months. CONCLUSION: Breast cancer was discovered in 5% of women with palpable breast thickening. Women with negative mammograms and US scans are at low risk for cancer but should, in our opinion, be followed up at short-term intervals with clinical examination and imaging if biopsy is not elected by their surgeon or clinician.     

Role of US-guided fine-needle aspiration with on-site cytopathologic evaluation in management of nonpalpable breast lesions

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate the accuracy of ultrasound (US)-guided fine-needle aspiration (FNA), with radiographic follow-up or surgical excision, in conjunction with on-site cytopathologic support in the management of nonpalpable breast lesions. MATERIALS AND METHODS: The findings of 266 consecutive mammographically or sonographically identified, nonpalpable lesions (228 patients) that underwent US-guided FNA were examined retrospectively. Clustered microcalcifications did not undergo biopsy with this method. Patients who underwent follow-up excisional biopsy or mammography with a duration of at least 24 months were included in the study. RESULTS: In all, 117 lesions met criteria for inclusion, of which 85 (73%) were diagnosed as benign at cytopathologic evaluation and underwent mammographic follow-up of at least 24 months (range, 24-67 months; mean, 36 months). Thirty-two lesions (27%) had either malignant or atypical cytopathologic findings, for which surgery was recommended. Eleven (9%) of the 32 had malignant cytopathologic findings from initial US-guided FNA, which were confirmed at surgical excision. The remaining 21 lesions (18%) were diagnosed as atypical on the basis of US-guided FNA results. Of these, 18 lesions underwent excisional biopsy: Two were diagnosed as carcinoma (not otherwise specified), and 16 were diagnosed with a variety of benign disorders. The remaining three patients with atypical lesions chose mammographic follow-up rather than surgical diagnosis, and their conditions have remained stable for more than 24 months. Of the 85 benign cases, one changed during follow-up (12 months) and underwent repeat biopsy, with malignancy noted. The sensitivity of US-guided FNA in identifying malignant lesions was 93% (13 of 14), and the specificity of a benign finding was 100% (102 of 102). The positive and negative predictive values of US-guided FNA supported by on-site cytopathologic evaluation were 100% (13 of 13) and 99% (102 of 103), respectively. CONCLUSION: Supported by appropriately trained on-site cytopathologists and in conjunction with follow-up mammography, US-guided FNA appears to be efficacious in the management of patients with abnormal radiographic findings. It is quick, relatively inexpensive, and minimally invasive, and, in the presence of competent cytopathologists, should be the modality of choice.     

False-negative breast screening assessment: what lessons can we learn?

AIM: To review women who have had breast cancer diagnosed following previous assessment of a screen-detected mammographic abnormality in order to ascertain the frequency and characteristics of false-negative assessment. MATERIALS AND METHODS: The assessment process was reviewed in the study population of 28 women. This included the nature of the lesion recalled for assessment, additional mammography, clinical and ultrasound findings, and the results of fine needle aspiration cytology and needle histology. RESULTS: The frequency of false-negative assessment was approximately 0.56%. The median time between false-negative assessment and diagnosis of breast cancer was 33 months. The most common mammographic lesion resulting in false-negative assessment was micro-calcification seen in 12 cases (43%). Only five of these 12 cases had image-guided biopsy, the remainder were thought to be benign on magnification views. Other mammographic abnormalities were nine masses (32%), five architectural distortions (18%) and two asymmetric densities (7%). Of the 16 women with mammographic lesions other than micro-calcifications 10 had a normal ultrasound. CONCLUSION: Radiological interpretation of indeterminate micro-calcifications as benign or malignant is unreliable. An isolated cluster of micro-calcification requires image-guided core biopsy with representative micro-calcification obtained on specimen radiography. Further mammography done at assessment, particularly paddle compression views, should be carefully analysed to ensure areas of architectural distortion have truly resolved. If one imaging modality shows a significant abnormality and another does not the cases must be managed on the basis of the abnormal finding. Burrell, H.C.et al. (2001). Clinical Radiology56, 385-388.     

Underestimation of the presence of breast carcinoma in papillary lesions initially diagnosed at core-needle biopsy

PURPOSE: To retrospectively determine the degree of underestimation of breast carcinoma diagnosis in papillary lesions initially diagnosed at core-needle biopsy. MATERIALS AND METHODS: Institutional review board approval and waiver of informed consent were obtained for this HIPAA-compliant study. Mammographic database review (1994-2003) revealed core biopsy diagnoses of benign papilloma (n=38), atypical papilloma (n=15), sclerotic papilloma (n=6), and micropapilloma (n=4) in 57 women (mean age, 57 years). Excisional or mammographic follow-up (>or=2 years) findings were available. Patients with in situ or invasive cancer in the same breast or patients without follow-up were excluded. Findings were collected from mammography, ultrasonography, core technique, core biopsy, excision, and subsequent mammography. Reference standard was excisional findings or follow-up mammogram with no change at 2 years. Associations were examined with regression methods. RESULTS: In 38 of 63 lesions, surgical excision was performed; in 25 additional lesions (considered benign), follow-up mammography (24-month minimum) was performed, with no interval change. In 15 lesions, 14-gauge core needle was used; in 48, vacuum assistance (mean cores per lesion, 8.7). Carcinoma was found at excision in 14 of 38 lesions. Core pathologic findings associated with malignancy were benign papilloma (n=1), sclerotic papilloma (n=1), micropapilloma (n=2), and atypical papilloma (n=10). Frequency of malignancy was one (3%) of 38 benign papillomas, 10 (67%) of 15 atypical papillomas, two (50%) of four micropapillomas, and one (17%) of six sclerotic papillomas. Excisional findings included lobular carcinoma in situ (n=2), ductal carcinoma in situ (n=7), papillary carcinoma (n=2), and invasive ductal carcinoma (n=3). Low-risk group (micropapillomas and sclerotic and benign papillomas) was compared with high-risk atypical papilloma group. Core findings were associated with malignancy at excision for atypical papilloma (P=.006). Lesion location, mammographic finding, core number, or needle type were not associated (P>.05) with underestimation of malignancy at excision. CONCLUSION: Benign papilloma diagnosed at core biopsy is infrequently (3%) associated with malignancy; mammographic follow-up is reasonable. Because of the high association with malignancy (67%), diagnosis of atypical papilloma at core biopsy should prompt excision for definitive diagnosis.     

Stereotactic core needle biopsy of nonpalpable breast lesions using a conventional mammography unit with an add-on device

OBJECTIVE: The purpose of this prospective study was to assess the accuracy of an add-on stereotactic unit for core needle biopsy of mammographic lesions. SUBJECTS AND METHODS. Between September 1994 and February 2001, 506 stereotactic core needle biopsies of mammographic lesions in 492 patients were performed in our center on a mammography unit with add-on stereotactic equipment. Of the initial 92 patients, 80 underwent stereotactic core needle biopsy and surgical excision simultaneously. In subsequent cases, surgical biopsy was performed after core biopsy in patients who had malignant or atypical histologic results or discordance between mammographic and pathologic findings. Follow-up mammography was advised for all patients whose core biopsy results were diagnosed as benign lesions. RESULTS: Histologic results for 506 lesions undergoing stereotactic core needle biopsy were as follows: 113 (22.3%) were malignant; 369 (72.9%), benign; and 24 (4.7%), atypical. Of 113 malignant lesions identified at stereotactic core needle biopsy, 111 were confirmed as malignant, whereas two showed no evidence of malignancy at surgical excision. Of 369 lesions diagnosed as benign at stereotactic core needle biopsy, 172 (46.6%) showed no change on follow-up mammography, 114 (30.9%) were lost to follow-up, and 83 (22%) underwent surgical excision. Of 24 lesions with atypical histology, 23 had surgical follow-up, six were malignant, nine were benign, and eight were confirmed as showing atypical histology. Stereotactic core needle biopsy of the 506 lesions was complicated by five (1.0%) cases of vasovagal attack and four (0.8%) cases of bleeding. The resulting sensitivity, specificity, and positive and negative predictive values were 98.3%, 93.0%, 86.0%, and 99.2% respectively. CONCLUSION: Biopsy with an add-on unit is safe, reliable, accurate, and cost-effective with results comparable to those reported for dedicated prone biopsy devices.     

Follow-up of benign results of stereotactic core breast biopsy

RATIONALE AND OBJECTIVES: The purpose of this study was to obtain long-term follow-up data on women with benign histologic results of a breast stereotactic core needle biopsy (CNB). MATERIALS AND METHODS: Mammography charts of 300 consecutive women who underwent prone stereotactic CNB with digital radiography were reviewed. Women with frankly malignant or suspicious histologic findings (51 patients) or a technically unsuccessful stereotactic CNB (one patient) were excluded. The remaining 248 benign core biopsies in 229 women were included in the study. RESULTS: Follow-up mammograms were obtained for 152 lesions with benign histologic results following stereotactic CNB. The mean length of follow-up after stereotactic CNB was 34.6 months. Cancer was diagnosed in six women who underwent surgical biopsies 1/2 to 30 months after benign stereotactic CNB. An initial chart review demonstrated that no follow-up data were available for 64 lesions, and information was missing for an additional seven. CONCLUSION: SCNB remains a sampling procedure that can result in false-negative histologic results. Intrinsic procedural issues were identified that could minimize the potential for missing a malignancy. Goals for patient compliance with follow-up recommendations fell short of expectations.     

Uncommon high-risk lesions of the breast diagnosed at stereotactic core-needle biopsy: clinical importance

PURPOSE: To assess the outcome of papillary lesions, radial scars, or lobular carcinoma in situ (LCIS) diagnosed at stereotactic core-needle biopsy (SCNB). MATERIALS AND METHODS: Retrospective review of 1,236 lesions sampled with SCNB yielded 22 papillary lesions, nine radial scars, and five LCIS lesions. Diffuse lesions such as papillomatosis, papillary ductal hyperplasia, papillary ductal carcinoma in situ (DCIS), and atypical lobular hyperplasia were not included. The mammographic findings, associated histologic features, and outcome were assessed for each case. RESULTS: Sixteen papillary lesions were diagnosed as benign at SCNB. Of these, five were benign at excision, and 10 were unremarkable at mammographic follow-up. At excision of an unusual lesion containing a microscopic papillary lesion, DCIS was found. Three of four papillary lesions suspicious at SCNB proved to be papillary carcinomas; the fourth had no residual carcinoma at excision. Eight of nine radial scars were excised, which revealed atypical hyperplasia in four scars but no malignancies. One LCIS lesion was found at excision to contain DCIS. CONCLUSION: Benign or malignant papillary lesions were accurately diagnosed with SCNB in the majority of cases. Cases diagnosed as suspicious for malignancy or with atypia or unusual associated histologic findings should be excised. No malignancies were found at excision of radial scars diagnosed at SCNB. Surgical removal of these lesions following SCNB may not be routinely necessary. DCIS was found in one lesion diagnosed as LCIS at SCNB, which suggests that removal of these lesions may be prudent.     

Breast cancer recurrence after lumpectomy and irradiation: role of mammography in detection.

Between 1977 and 1989, 102 of 1,145 patients treated with lumpectomy and radiation as an alternative to mastectomy required subsequent biopsy for suspected ipsilateral recurrence. The authors reviewed the mammograms of 58 of those patients for whom at least two sets of mammograms were available, including one set obtained within 3 months of the subsequent repeated biopsy. Of 38 biopsy-proved recurrences, 13 (34%) were detected with mammography alone, 17 (45%) with palpation alone, and eight (21%) with both mammography and palpation. While standard mammographic criteria for biopsy were followed, distortions and calcifications inherent to posttreatment appearances necessitated judicious modifications. As anticipated, sensitivities and positive predictive values showed more impairment within the lumpectomy quadrant. In addition, all cases of purely in situ cancer were detected solely with mammography. Mammography plays an important complementary role to physical examination in posttreatment follow-up. On the basis of these findings, a follow-up algorithm for the ongoing evaluation of these patients was developed.     

Usefulness of mammography and sonography in women less than 35 years of age

Indications, clinical history, mammographic findings, and clinical outcome were reviewed in 1,016 women younger than 35 years who underwent mammography during an 8-year period. The indications for mammography were a palpable mass in 454 (44.7%), findings at routine screening in 237 (23.3%), lumpiness in 29 (14.9%), unilateral nipple discharge in seven (3.5%), localized breast tenderness in six (5.1%), adenopathy in three (1.9%), diffuse tenderness in two (2.9%), bilateral nipple discharge in two (1.5%), and miscellaneous in four (2.2%). In 405 women (39.9%), at least two-thirds of the breast tissue was radiodense; however, in 299 (29.4%) women the breast was predominantly fatty, allowing for excellent mammograms. Six women had carcinomas: Mammographic findings prompted biopsy in one patient, indicated a benign-appearing mass (found to be solid at sonography or aspiration) in three patients with a palpable mass (contributing to delay in biopsy in two), and were negative in two. Sonography was performed in 389 women and was useful in preventing unnecessary biopsy of cysts but was not useful in differentiating benign from malignant solid masses. Younger women with persistent localized breast symptoms should undergo a tailored mammographic examination, but negative findings or findings of a benign lesion should not preclude biopsy of a palpable solid mass.     

Reassessment of breast cancers missed during routine screening mammography: a community-based study

OBJECTIVE: The purpose of this study was to have a series of screening mammograms from routine practice, including false-negative results, reviewed by peer community-based experienced radiologists to determine the percentage of these false-negative findings that might be considered detectable. MATERIALS AND METHODS: All screening cases for 1997 and 1998 were identified from the Carolina Mammography Registry. Mammographic assessments from community mammography practices were linked with population-based cancer outcomes. The findings of four community-based radiologists who reviewed the mammograms of 339 asymptomatic women were 93 false-negatives, 180 true-negatives, and 66 false-positives. The percentage of false-negative, true-negative and false-positive findings on breast films that reviewers evaluated was determined. The findings of the reviewers were compared with the original interpreting radiologists' assessments. RESULTS: The overall breast-specific workup rate by the reviewing radiologists was 21%. The average workup rate for the false-negative findings was 42% (range, 35-51%). Adjusting for the 13% workup rate in the cancer-free breasts, the percentage of false-negative findings that were detectable was estimated to be 29%. CONCLUSION: This peer review of screening mammograms from a population-based screening registry estimated a missed detectable cancer rate of 29%. Thus, 71% of cancers missed at screening would not have been worked up by peers in the same community.     

Diagnostic errors in mammography. I. False negative results

The authors evaluate 1455 consecutive breast cancers detected 1985-1987, undergoing mammography 6 months before diagnosis at the most. One hundred and seventy-eight cases reported as negative/benign were assumed as false negatives. Overall sensitivity was 88%, and was influenced by tumor stage (TIS = 80%, T1 = 83%, T2 = 91%, T3-4 = 95%) and patients' age (less than 40 = 76%, 40-49 = 78%, 50-59 = 91%, greater than 59 = 94%). Sensitivity varied also with readers' experience full- or part-time involved in reading mammograms (total cases = 92% vs 88%, T1 cases = 86% vs 74%). No correlations were evidenced between mammographic sensitivity and histologic type of cancer. Palpation and cytology allowed the correct identification of 98% of mammographic false negatives. One hundred and seventy-eight false negatives and 142 more cases showing evidence of a mammographic error more than 6 months before diagnosis were reviewed to assess the most common types of radiologic fault. A benign-like lesion was the most frequent finding (49.4%), whereas suspicious signs were infrequent at review (16.6%). Failure to encompass the lesion in the mammographic field or poor technique accounted for 3.8 or 1.3% of cases, respectively. 29% of false-negative subjects (mostly young or with a dense breast) showed no lesion even at review. This study confirms the good sensitivity of mammography but suggests a less confident diagnostic approach in younger women, stresses the need for other tests whenever a minimal doubt is present, and encourages the radiologist's full-time involvement in mammography and breast diagnosis to achieve greater experience and improve his diagnostic sensitivity.     

Stereotaxic core needle biopsy of breast microcalcifications obtained using a standard mammography table with an add-on unit.

OBJECTIVE: To demonstrate the reliability of stereotaxic biopsy of indeterminate microcalcifications using a standard mammography table with an add-on unit. METHODS: In 121 cases of indeterminate microcalcifications, core biopsy was performed using a standard mammography table with an add-on stereotaxic unit. Microcalcifications were identified on radiography of core specimens. RESULTS: Microcalcifications and a definitive histologic diagnosis were obtained in 112 core biopsies (92.6%), with no significant complications. In 23 lesions frank malignancy was diagnosed, and all of these diagnoses were confirmed on surgery. Pathologic examination suggested carcinoma in 4 lesions, and open biopsy confirmed malignancy in 3 of these cases. Four lesions showed atypical ductal hyperplasia. Benign disease was diagnosed in 81 lesions, of which 78 remained stable on mammographic follow-up (mean 16 months later) and 3 were subjected to surgical biopsy (of which 1 was malignant and 2 were benign). Nine cases were technically unsatisfactory because microcalcifications were not sampled. CONCLUSION: Stereotaxic core biopsy performed with an add-on unit is a safe and reliable technique for biopsy of indeterminate microcalcifications. For successful biopsy, microcalcifications must be harvested. Pathologic results should be correlated with mammographic findings. The accuracy rate compares favourably with results reported using prone biopsy tables. In an era of cost containment, this alternative to prone biopsy tables could result in significant savings in terms of capital investment and use of hospital rooms. In this study, surgical biopsy could have been avoided in 64.5% of cases.     

Benign breast lesions: minimally invasive vacuum-assisted biopsy with 11-gauge needles patient acceptance and effect on follow-up imaging findings

PURPOSE: To evaluate patient acceptance of stereotactic or ultrasonographically (US) guided directional vacuum-assisted 11-gauge needle biopsy of breast lesions and short- and long-term changes at mammography and US resulting from the procedure. MATERIALS AND METHODS: For 91 benign lesions that had been sampled at either stereotactic or US-guided directional vacuum-assisted breast biopsy performed with 11-gauge needles, clinical, mammographic, and US changes were evaluated 1 week after biopsy; 6-month follow-up findings were available for 74 lesions. The subjective outcome of the procedure and patient satisfaction were assessed on the basis of a patient-completed questionnaire that incorporated a multistage scoring system. Statistical analysis of scores for condition for both biopsy methods was performed with the chi2 test. RESULTS: Adverse events occurred during the procedure in four patients. Clinically visible hematomas were observed at 1-week follow-up in 79% of patients. Densities were observed on mammograms in 46% of patients 1 week after biopsy; hematomas with a maximum diameter of 2 cm were seen on sonograms in 74%. Six months after biopsy, mammography revealed discrete architectural changes in one case. No abnormalities were found at 6-month follow-up US. Fifteen patients had various complaints during the procedure; six reported feeling constrained during the first few days after biopsy, and one patient was not satisfied with the cosmetic result. No patient reported a retrospective preference for surgical biopsy instead of directional vacuum-assisted biopsy. Analysis of scores for the stereotactic and US-guided methods revealed a significant difference (P <.001) in favor of the stereotactic method for condition during biopsy, while scores for condition in the first days after biopsy were more equally distributed between the two methods (P =.386). CONCLUSION: Directional vacuum-assisted 11-gauge needle biopsy of the breast is well accepted by patients and rarely produces changes that may alter the mammographic or sonographic appearance of the breast at 6-month follow-up.     

Optimization of X-ray mammography and technetium-99m methoxyisobutylisonitrile scintimammography in the diagnosis of non-palpable breast lesions

The purpose of this study was to evaluate the contribution of technetium-99m methoxyisobutylisonitrile (MIBI) scintimammography to the early diagnosis of breast cancer in 78 patients with non-palpable breast lesions detected by mammography. In all cases biopsy was indicated and they were classified into three groups according to the mammographic findings: high (28), intermediate (30) and low (20) mammographic probability of malignancy. Histological diagnosis confirmed 37 benign and 41 malignant lesions. In the high-probability group ^99mTc-MIBI scintimammography changed the four false-positives into true negatives at the expense of two false-negatives; in the intermediate group it changed nine of the 17 false-positives into true-negatives at the expense of one false-negative, and in the low-probability group it changed five of the 16 false-positives into true-negatives without false-negatives. Applying scintimammography to patients included in the intermediate and low-probability groups together, 14 of the 33 mammographic false-positives were changed into true-negatives with 1 false-negative; thus, 41% of the unnecessary biopsies would have been avoided. When MIBI scintimammography was applied to the low-probability group, the negative predictive value was 100% and the unnecessary biopsies would have been reduced by 31%. Received 10 November 1997 and in revised form 19 January 1998