Atypical lobular hyperplasia or lobular carcinoma in situ at core-needle breast biopsy

PURPOSE: To review outcomes of lesions diagnosed at core-needle breast biopsy as atypical lobular hyperplasia (ALH) or lobular carcinoma in situ (LCIS). MATERIALS AND METHODS: Results from 1,400 consecutive core-needle breast biopsies were reviewed. Twenty-five (1.8%) biopsy samples with the diagnosis of lobular neoplasia (15 with ALH and 10 with LCIS) adjacent to or in a targeted benign lesion were found. Lesions were excised (n = 15) or followed up (n = 10) at least 22 months. RESULTS: Of the 15 lesions with ALH, 13 (87%) were adjacent to (n = 12) or associated with (n = 1) microcalcifications, and two (13%) were in masses. Six lesions with residual calcifications were excised. One lesion was diagnosed as ductal carcinoma in situ (DCIS), and five were benign (residual ALH was seen in four). One excised mass showed residual ALH. Six lesions were gone at follow-up, one cluster of microcalcifications was decreased in size, and one fibroadenoma with ALH was stable. Of the 10 lesions with LCIS, seven (70%) were adjacent to (n = 6) or associated with (n = 1) microcalcifications, and three (30%) were in or adjacent to masses. Five lesions with LCIS and residual microcalcifications were excised. Three yielded atypical ductal hyperplasia (ADH); one, residual LCIS; and one, ALH. Three masses with LCIS were excised. One showed residual LCIS; one, a papilloma with adjacent LCIS; and one, a fibroadenoma with LCIS in it. One cluster of microcalcifications was gone at follow-up, and one was stable. CONCLUSION: After a diagnosis of lobular neoplasia at core biopsy, residual microcalcifications are viewed in the context of a patient at higher risk of cancer. Of 11 lesions with residual microcalcifications, three (27%) were ADH and one (9%) was DCIS.     

Lobular carcinoma in situ of the breast: mammographic features

Lobular carcinoma in situ (lobular neoplasia; LCIS) of the breast is most commonly an incidental microscopic finding in breast tissue removed for some other reason. The authors reviewed the clinical and mammographic features and surgical findings in 26 cases of LCIS not associated with other breast abnormalities. In 16 instances, needle localization was performed before removal of the tissue, which yielded LCIS on histologic examination. Calcifications were the most common reason for biopsy, although there were no distinctive mammographic features of LCIS.     

Microcalcifications around a collagen-based breast biopsy marker: complication of biopsy with a percutaneous marking system

OBJECTIVE: The purpose of this article is to present the cases of four women who underwent percutaneous breast biopsy with deployment of a titanium metallic marker embedded in a bioresorbable collagen plug. Routine follow-up mammography after benign pathologic results were obtained revealed new fine microcalcifications at the biopsy sites, requiring repeat biopsy. Pathologic examination confirmed the presence of microcalcifications associated with an acidophilic foreign material. CONCLUSION: Awareness that development of microcalcifications can complicate biopsy performed with collagen-based markers is important for correct mammographic interpretation and management.     

Differentiation of benign and malignant local tumor recurrence after lumpectomy

During a 5-year period, 28 women who had been treated conservatively for breast carcinoma had 29 reexcisions of the lumpectomy site because of suspicion of a recurrent malignant tumor. Biopsy results were benign in 19 cases and malignant in 10 cases. Sixteen of the 19 benign tumors had developed within 2 years after therapy. In 16 benign cases, a palpable lump developed at the scar and was found on biopsy to be fat necrosis or fibrosis. Seven of these cases had normal mammographic findings. Three women with abnormal mammographic findings but a normal breast examination had punctate microcalcifications develop at the scar; these were due to fibrosis in two and sclerosing adenosis in the other. Of the 10 malignant recurrent tumors, seven were palpable, four of which also were identifiable by mammography. Of seven mammographically identifiable recurrent tumors at the surgical site, four were palpable. Mammographic findings were a single mass in two cases, multiple masses in one, microcalcification in three, and a mass with microcalcifications in one. Malignant microcalcifications were all linear, irregular, and in one case branching. Mean time to recurrence in these 10 women was 3 years. This experience suggests that benign disease usually occurs at the scar within 2 years after the original therapy and when palpable may not show changes on mammography. When microcalcifications do occur, they are usually punctate.     

US of mammographically detected clustered microcalcifications

PURPOSE: To determine whether ultrasonography (US) can depict breast masses associated with mammographically detected clustered microcalcifications and whether the visibility at US is different between benign and malignant lesions. MATERIALS AND METHODS: Ninety-four patients with 100 mammographically detected microcalcification clusters prospectively underwent US with a 10- or 12-MHz transducer before mammographically guided presurgical hook-wire localization. The visibility of breast masses at US was correlated with histologic and mammographic findings. RESULTS: Surgical biopsy revealed 62 benign lesions, 30 intraductal cancers, and eight invasive cancers. At US, breast masses associated with microcalcifications were seen in 45 (45%) of 100 cases. US depicted more breast masses associated with malignant (31 [82%] of 38) than with benign (14 [23%] of 62) microcalcifications (P: <.001). In malignant microcalcification clusters larger than 10 mm, US depicted associated breast masses in all 25 cases. There was no statistically significant difference in shape and distribution of calcific particles, as well as in breast composition, at mammography between US visible and invisible groups. CONCLUSION: Given a known mammographic location, US with a high-frequency transducer can depict breast masses associated with malignant microcalcifications, particularly clusters larger than 10 mm. US can be used to visualize large clusters of microcalcifications that have a very high suspicion of malignancy.     

Carcinoma within fibroadenomas: mammographic features

The mammographic features of carcinoma originating within a fibroadenoma in 24 patients were studied by means of retrospective review of pathologic slides. Histologic examination showed that the lesions were lobular carcinoma in situ (LCIS) (seven patients), ductal carcinoma in situ (DCIS) (13 patients), synchronous LCIS and invasive lobular carcinoma (one patient), and synchronous LCIS and DCIS (three patients). In all patients the mammographic manifestation was a mass 1.0 cm or greater in diameter; 14 masses were 1-2 cm in diameter, and the remainder were more than 2 cm in diameter. Features that were considered suspect included large size, indistinct margins, and clustered microcalcifications. In three patients, microcalcifications within the mass raised suspicion of malignancy. At histologic examination these microcalcifications were associated with the intraductal carcinoma harbored in the fibroadenoma in only one of these patients. Fibroadenomas that harbor carcinoma may be indistinguishable from common benign fibroadenomas, but their occurrence is rare. In this study, a single patient had invasive lobular carcinoma; all the other lesions were in situ lesions.     

Automated stereotactic core needle biopsy of microcalcifications with correlation to surgical biopsy.

PURPOSE: To compare pathologic findings from stereotactic core and excisional biopsies in patients with microcalcifications in the breast. MATERIAL AND METHODS: Stereotactic core needle biopsies of 101 lesions with mammographic evidence of microcalcifications were performed with long-throw (2.2 cm) automated core biopsy devices fitted with 2.1-mm needles. The core specimens were placed on microscope slides and radiographed. The pathologic features of core and excisional specimens were compared. RESULTS: In 100 of the 101 breast lesions, a correct choice for an additional diagnostic procedure or definitive treatment could have been made upon histopathologic findings of the core needle biopsy. CONCLUSION: Stereotactic core needle biopsy is a reliable alternative to surgical biopsy of breast lesions with microcalcifications provided that specimen radiography has been performed to ensure that appropriate tissue has been obtained. Excisional biopsy may be avoided if microcalcifications are visible in radiographs of core biopsy specimen with benign histology.     

The significance of mammographic calcifications in early breast cancer detection

3,126 medical reports on women sent to mammary biopsy following breast examination at the Florence Center for the Study and Prevention of Cancer in November 1978-July 1982 were reviewed in order to assess the diagnostic significance of mammographic microcalcifications. All mammographies were examined in order to assess the presence and morphological aspects of the microcalcifications on the bioptic site. Microcalcifications were classified on the basis of the following morphological criteria: spatial disposition (isolated, clustered, diffuse); total number; number per cm; morphological aspect (dot-like, stick-like or ramified); shape (regular or irregular); radiological density; association with mammographic opacity; maximum and average diameter. Microcalcifications were encountered in 19.7% of 157 breast cancer diagnosed in a mammographic screening programme conducted on the asymptomatic population in 19.5% of 953 breast cancers diagnosed in self-referring women (most with symptoms). Among cases where subsequent histological examination revealed a benign pathology, microcalcifications were more frequent in the cases deriving from the screening programme (14.5% of 198 cases) than among self-referred cases (4.5% of 1818 cases). The presence of microcalcifications is in itself a predictive sign of the presence of a carcinoma (positive predictive value = 66.2%) but this radiological sign is only present in 20% of breast cancers. Among the various parameters considered in assessing the diagnostic significance of microcalcifications, irregular shape was the most indicative of carcinoma with a predictive value of 80% and presence in 88% of carcinoma with microcalcifications. Other microcalcification parameters with a particular predictive significance are diffuse spatial disposition, total number (over 10) and number per cm (over 50), site contiguous with a mammographic opacity and a mean diameter of 0.6-0.9 mm. Unfortunately these latter parameters are only 24% of tumour cases with microcalcifications. The incidence of microcalcifications in cancer does not vary according to age, but is strongly correlated with the tumour stage. In particular microcalcifications are found in about 1/3 of in situ carcinomas. In invasive cancers, the presence of microcalcifications tends to increase with the diameter of the lesion. No correlation was found in breast cancers between the presence of microcalcifications, lymph node condition and histological type.(ABSTRACT TRUNCATED AT 400 WORDS)     

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.     

Ultrasound guided core biopsy of suspicious mammographic calcifications using high frequency and power Doppler ultrasound

AIM: The pre-operative diagnosis of suspicious mammographic microcalcifications usually requires stereotactic needle biopsy. The aim of this study was to evaluate if high frequency 13 MHz ultrasound (HFUS) and power Doppler (PD) can aid visualization and biopsy of microcalcifications. MATERIALS AND METHODS: Forty-four consecutive patients presenting with microcalcifications without associated mammographic or palpable masses were examined with HFUS and PD. Ultrasound-guided core biopsy (USCB) was performed where possible. Stereotactic biopsy was carried out when US-guided biopsy was unsuccessful. Surgery was performed if a diagnosis of malignancy was made on core biopsy or if the repeat core biopsy was non-diagnostic. RESULTS: Forty-one patients (93%) had ultrasound abnormalities corresponding to mammographic calcification. USCB was performed on 37 patients. In 29/37, USCB obtained a definitive result (78.4%). USCB was non-diagnostic in 4/9 benign (44.4%) and 4/28 (14.3%) malignant lesions biopsied. The complete and absolute sensitivities for malignancy using USCB were 85.7% (24/28) and 81% (23/28), respectively. USCB correctly identified invasive disease in 12/23 (52.2%) cases. There was no significant difference in the presence of abnormal flow on PD between benign and malignant lesions. However, abnormal PD vascularity was present in 43.5% of invasive cancer and was useful in directing successful biopsy in eight cases. CONCLUSION: The combination of high frequency US with PD is useful in the detection and guidance of successful needle biopsy of microcalcifications particularly where there is an invasive focus within larger areas of DCIS.     

Evaluation of the stereotactic 8G vacuum-assisted breast biopsy in the histologic evaluation of suspicious mammography findings (BI-RADS IV)

PURPOSE: The purpose of this study was to evaluate the potential of the new 8G stereotactic vacuum-assisted breast biopsy (ST-driver, Mammotome; Ethicon Endosurgery) in the histologic evaluation of BI-RADS IV microcalcifications. MATERIALS AND METHODS: Fifty-eight patients with 61 mammographic BI-RADS IV microcalcifications underwent stereotactic vacuum-assisted breast biopsy (SVAB). The new 8G system was mounted on the ST driver, which was formerly used only with the hand-held version under sonographic guidance. The evaluation criteria for each biopsy were minimally invasive and operative histologies, the time needed for biopsy, the amount of bleeding, number of rotations and specimen, the degree of resection, and the complications. RESULTS: Fifty-eight of 61 biopsies were technically successful because > or = 50% were resected (29 x 100%, 8 x 90%, 5 x 80%, 6 x 70%, 3 x 50%, 3 x 0%). In 7 cases with representative biopsies of segmental suspicious microcalcifications, the degree of resection could not be exactly measured. All but 2 biopsies were performed without clinically relevant complications and after gaining enough specimens (? 12.6 specimen, 1.85 rotations). Those 2 patients showed evidence of severe bleeding into the breast tissue and operative revision had to be performed (3.5%). The size of intramammary hematoma was measurable in 27 biopsies and showed a range from 0.5 to 5 cm (? 2.7 cm). The average external bleeding was still low with 16 mL (5-80 mL). In 3 of 61 lesions, it was not possible to gain representative tissue as a result of displacement of the lesion after introducing or shooting the needle. The average time needed for all biopsies was 28.2 minutes for all but 5 very complicated biopsies, which took 16.1 minutes. The histologic findings with further operative workup were: 10 ductal carcinomas in situ (DCIS), 4 atypical ductal hyperplasias, 1 atypical lobular hyperplasias (ALH), 3 lobular carcinomas in situ (LCIS), and 6 invasive ductal carcinomas. In 7 of 12 of the initial DCIS histologies, the operative histology was also DCIS, whereas in 4 of 12, no residual malignant tumor was found. In 1 of 12 patients with an initial DCIS histology, operative histology revealed invasive ductal cancer (8.3%). The cases with lobular lesions (ALH, LCIS) did not show any evidence for residual tissue in the operative workup. Most frequent benign histologies were mastopathy (13), ductal hyperplasia (9), fibroadenoma (8), and sclerosing adenosis (5). The control examinations (maximum 1 year) did not show any signs for a false-negative biopsy. CONCLUSION: The 11-G SVAB has proven to be a perfect adjunct to the existing breast biopsy methods. The new 8G SVAB speeds up the method when used for the same size of lesions and enables the user to representatively biopsy lesions up to 3 cm in diameter. The method is still minimally invasive; however, the amount of hematomas as well as clinically relevant complications is increased.     

Sedimented calcium in benign breast cysts: the full spectrum of mammographic presentations

We retrospectively reviewed the mammograms of 318 patients that showed sedimented calcifications within benign breast cysts to describe the natural history and full spectrum of the mammographic appearances. Sedimented calcifications are seen in approximately 4% of symptomatic women undergoing mammography. Their recognition is important to avoid unnecessary workup, follow-up, or biopsy. Key to recognition is the difference in their radiographic features on lateral and craniocaudal views. The classic appearance is that of milk of calcium, seen as linear, curvilinear, or teacup-shaped particles on horizontal-beam lateral views and as ill-defined smudges on vertical-beam craniocaudal views. The most common presentation is multiple, bilateral, scattered and occasionally clustered calcifications within microcysts. Other presentations include milk of calcium within microcysts in a unilateral, clustered distribution; milk of calcium within macrocysts; sandlike calcifications (discrete particles rather than smudges on craniocaudal view) within cysts of various sizes; and rarely, milk of calcium within the lipid cysts of either fat necrosis or galactoceles. None of our cases has proved to be malignant. However, adjacent malignancies are a potential pitfall. We encountered eight patients with carcinoma presenting as clustered microcalcifications in a breast also containing typical sedimented calcifications. In each of these cases, the malignant calcifications could be distinguished by their mammographic appearance. The recognition of sedimented calcifications present in about 4% of symptomatic women undergoing mammography is important because these characteristic calcifications are an indication of benignity. Malignant-appearing microcalcifications found in the vicinity of sedimented calcifications can be distinguished and require biopsy.     

Characterization and guided-procedures of breast suspicious microcalcifications: can MicroPure ultrasound do it?

Objective

To assess the diagnostic value of high-frequency (MicroPure) ultrasound in evaluating suspicious microcalcifications and to determine its capability in biopsy guidance.

Subjects and methods

Sixty-two cases with suspicious microcalcifications detected on mammographic examination had been re-evaluated by MicroPure US. The studied cases underwent true cut tissue/surgical excision biopsy. Histopathology revealed 25 benign and 37 malignant lesions and was considered the gold standard of reference.

Results

Malignant microcalcifications were easier to be visible at MicroPure US, as they were detected in 86.5% (n = 32/39) compared to only 68% (n = 17/25) of the benign lesions. US depicted more breast masses associated with malignant microcalcifications in 78% (n = 29/37) than those associated with benign ones seen in 36% (n = 9/25).Visibility of suspicious microcalcifications at US was aided by preliminary mammogram. Given known mammography location of these microcalcifications had made their visualization accessible by MicroPure US in 79% (n = 49) of the cases.

Conclusion

MicroPure ultrasound cannot discriminate benign from malignant breast microcalcifications. MicroPure can be useful in detecting clustered microcalcifications that are not accessible by B-mode ultrasound; provided knowledge of their mammographic location and thus can provide better guidance for pre-surgical wire localization and ultrasound-guided biopsies.     

Contrast-enhanced MR imaging in patients with BI-RADS 3-5 microcalcifications

PURPOSE: The aim of this study was to evaluate the role of magnetic resonance imaging (MRI) in patients with microcalcifications classed as Breast Imaging Reporting and Data Systems (BI-RADS) 3-5. MATERIALS AND METHODS: Fifty-five patients with mammographic microcalcifications classified as BI-RADS categories 3, 4 or 5 underwent MRI and biopsy with stereotactic vacuum-assisted biopsy (VAB). Our gold standard was microhistology in all cases and histology with histological grading in patients who underwent surgery. Patients with a microhistological diagnosis of benign lesions underwent mammographic follow-up for at least 12 months. MRI was performed with a 1.5-Tesla (T) unit, and T1 coronal three-dimensional (3D) fast low-angle shot sequences were acquired before and after injection of paramagnetic contrast agent (0.1 mmol/kg). MRI findings, according to the Fisher score, were classified into BI-RADS classes. In patients with cancer who underwent surgery, we retrospectively compared the extension of the mammographic and MRI findings with histological extension. RESULTS: Histology revealed 26 ductal in situ cancers (DCIS) and ductal microinvasive cancers (DCmic), three atypical ductal hyperplasias (ADH) and 26 benign conditions. Histological grading of the 26 patients with cancer revealed four cases of G1, 11 cases of G2 and 11 cases of G3. If we consider mammographic BI-RADS category 3 as benign and BI-RADS 4 and 5 as malignant, mammography had 77% sensitivity, 59% specificity, 63% positive predictive value (PPV), 74% negative predictive value (NPV) and 67.2% diagnostic accuracy. If we consider MRI BI-RADS categories 1, 2 and 3 as benign and 4 and 5 as malignant, MRI had 73% sensitivity, 76% specificity, 73% PPV, 76% NPV and 74.5% diagnostic accuracy. As regards disease extension, mammography had 45% sensitivity and MRI had 84.6% sensitivity. CONCLUSION: Mammography and stereotactic biopsy still remain the only techniques for characterising microcalcifications. MRI cannot be considered a diagnostic tool for evaluating microcalcifications. It is, however, useful for identifying DCIS with more aggressive histological grades. An important application of MRI in patients with DCIS associated with suspicious microcalcifications could be to evaluate disease extension after a microhistological diagnosis of malignancy, as it allows a more accurate presurgical planning.     

Lobular carcinoma in situ of the breast: clinical, pathologic, and mammographic features

Lobular carcinoma in situ (LCIS) was diagnosed in 165 surgical specimens (119 patients) at our institution between 1974 and 1987. LCIS was seen more often in younger women (mean age, 49 years) than other breast carcinomas were (mean age, 58 years). Sampling of a single breast revealed multifocal disease in 70% (96/138). When both breasts were sampled, bilateral foci were found in 50% (41/82). Of 165 breasts with foci of LCIS, 37% (61/165) had simultaneously occurring invasive cancers in the same breast. Direct mammographic-pathologic correlation of foci of LCIS was possible in 73 breasts (67 patients). Microcalcifications were an indication for biopsy in 49% (20/41) of breasts with a mammographic abnormality, but were a nonspecific finding often found in tissues adjacent to foci of LCIS. The mammogram was normal in 44% (32/73) of breasts with foci of LCIS. The mammograms of patients with LCIS and those from a group of age-matched control subjects were compared by using a modified form of Wolfe's criteria and the percentage of fibroglandular elements. LCIS was seldom found in an N1 breast (1% vs 29%) or in a breast with less than 25% of its parenchymal area occupied by fibroglandular density (3% vs 33%). Compared with the control group, breasts with LCIS had more than 50% fibroglandular density (85% vs 45%) and a much higher frequency of the DY pattern (56% vs 36%). More fibroglandular density was seen in the LCIS group at all ages. Postmenopausally, the frequencies of the DY pattern and fibroglandular density greater than 50% in LCIS patients were nearly double those in the control group. LCIS patients have disease of the entire breast parenchyma, characterized by multifocality and bilaterality of various forms of lobular disease. Their mammograms reveal a higher rate of the DY pattern and higher percentages of fibroglandular or parenchymal density than those of age-matched controls. In LCIS patients, persistence of the DY pattern, or large amounts of fibroglandular density postmenopausally supports the concept that mammographically dense breasts are a marker for increased cancer risk in women 50 years old and older.     

Ultrasound demonstration of mammographically detected microcalcifications

Purpose: To evaluate the capabilities of breast ultrasound (US) for identifying microcalcifications in benign breast changes, in situ carcinomas, and small non-palpable invasive carcinomas.Material and Methods: Forty-six consecutive patients with 49 clustered microcalcifications detected by mammography were included in this prospective study. Patients with palpable breast lesions were excluded. Breast US was performed with knowledge of mammographic findings for presence and visibility of microcalcifications, and for parenchymal structure abnormalities. Mammographic and US findings were compared with histology.Results: Nine ductal in situ carcinomas, 2 lobular in situ carcinomas, 11 invasive carcinomas and 27 benign lesions were confirmed by histology. For all lesions, US achieved a sensitivity of 75% in the detection of microcalcifications. The detection rate for microcalcification in invasive and in situ carcinomas was 100%. In 11 cases, no microcalcifications were visible on US; they all proved to be benign on histology.Conclusion: Microcalcifications in malignant lesions are reliably recognized by US. They are, however, difficult to detect in fibrocystic breast changes.     

Computer-aided preoperative diagnosis of microcalcifications on mammograms

PURPOSE: To evaluate of a computer-aided method for differentiating malignant from benign clustered microcalcifications. MATERIAL AND METHODS: Our material was 350 suspicious microcalcifications on mammograms from 330 female patients who underwent breast biopsy (after hook wire localization and under mammographic guidance). The histologic findings were malignant in 140 cases (40%) and benign in 210 cases (60%). Those clusters were manually detected, computer-aided analyzed and quantitatively estimated. Besides computer analysis, 3 physicians-observers (2 radiologists and 1 breast surgeon) evaluated the malignant or benign nature of the clustered microcalcifications. The performance of the artificial network, each observer and the three observers as a group was evaluated by receiver operating characteristics (ROC) curves. RESULTS: Comparison of the ROC curves revealed the following AUC values (area under the curve): computer - 0.950, physician 1 - 0.815, physician 2 - 0.830, physician 3 - 0.830, and physicians as a group - 0.825. The results, compared by the student t-test for paired data, showed a statistically significant difference between computer analysis and physicians' performance, independently and as a group. CONCLUSION: Our study showed that computer analysis achieved statistically significantly better performance than that of physicians in the classification of malignant and benign calcifications.     

Stereotactic 11-gauge vacuum-assisted breast biopsy: influence of number of specimens on diagnostic accuracy

PURPOSE: To determine whether number of specimens obtained at stereotactic 11-gauge vacuum-assisted breast biopsy with the patient prone influences diagnostic accuracy and to determine whether this number varies depending on mammographic appearance of lesions as masses or microcalcifications. MATERIALS AND METHODS: Biopsy was prospectively performed in 100 patients (median age, 55 years; range, 31-81 years) with 100 lesions that were mammographically evident as masses (n = 50) and microcalcifications (n = 50) with standardized protocol to acquire 20 specimens per lesion in three 360 degrees probe rotations at one skin entry site. Specimens were histologically evaluated sequentially, and findings were compared with results of surgical excision or of mammographic follow-up for at least 24 months. Differences in diagnostic yield after each probe rotation and differences in diagnostic yield between masses and microcalcifications were determined with chi(2) test. RESULTS: Up to 12 specimens harvested within two 360 degrees probe rotations were necessary to yield correct diagnosis in 96% of patients with masses and 92% of patients with microcalcifications. Diagnostic yield was not improved with more than 12 specimens for masses or microcalcifications. In two (4%) of 47 patients with lesions that were eventually diagnosed as cancer, results at stereotactic biopsy indicated they were benign. Underestimation of diagnosis of lesions as atypical ductal hyperplasia and ductal carcinoma in situ occurred in two (50%) of four and two (17%) of 12 lesions, respectively. With 20 specimens harvested during three probe rotations, there was no statistically significant difference in diagnostic yield between patients with masses and those with microcalcifications (P =.68). CONCLUSION: At 11-gauge vacuum-assisted biopsy, highest diagnostic yield was achieved with 12 specimens per lesion, independent of mammographic appearance of the lesion. Even with standardized retrieval of 20 specimens per lesion, underestimation of disease still occurs.