The additional value of US to mammography in the diagnosis of breast cancer. A prospective study.

PURPOSE: To assess the additional value of ultrasonography (US) to mammography in the diagnosis of malignant breast tumors. MATERIAL AND METHODS: Prospectively recorded final assessment categories for mammography and US were compared for 327 (228 palpable and 99 nonpalpable) consecutive malignant tumors confirmed at histology. The additional value of US was assessed for a subpopulation of 71 of these 327 malignancies after excluding mammographically conclusive malignant findings, ductal carcinomas in situ (DCIS), and invasive carcinomas presenting with suspicious microcalcifications, since there is no indication for performing US in these patients. RESULTS: A total of 267 (82%) of the 327 malignant tumors were correctly diagnosed on both imaging modalities. Mammography correctly diagnosed 41 cancers with false-negative US findings as compared with 11 true-positive US diagnoses of malignant tumors with false-negative findings on mammography (McNemar test p<0.001). US correctly diagnosed ("upgraded") 31 (10%) of the 327 malignant tumors with benign or indeterminate mammographic diagnoses. In the subpopulation, US upgraded 20 (42%) of 48 palpable and 10 (44%) of 23 nonpalpable malignant tumors. CONCLUSION: The overall additional value of US to mammography in the diagnosis of breast cancer was rather limited in a population of mixed malignant tumors. Excluding cancers with mammographically conclusive diagnosis and suspicious microcalcifications as well as DCIS from analysis, US correctly upgraded more than 40% of palpable and nonpalpable malignant tumors.     

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.     

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.     

Periodic mammographic follow-up of probably benign lesions: results in 3,184 consecutive cases

The author prospectively evaluated the value of periodic mammographic surveillance among 3,184 consecutive cases of nonpalpable, probably benign breast lesions detected with mammography. Follow-up consisted of four mammographic examinations during a 3- or 3.5-year period. Clinical outcome was ascertained in each case after the study period, whether or not patients complied with the protocol. Probably benign lesions were subsequently found to be malignant in 17 cases (positive predictive value for cancer, 0.5%). Fifteen of the 17 cancers were identified by means of interval mammographic change prior to development of a palpable mass; all 17 were stage 0 or stage 1 tumors. All 17 women who had cancer currently show no evidence of tumor recurrence (median duration of follow-up, 5 years). These results should help establish the validity of managing mammographically detected, probably benign lesions with periodic mammographic surveillance. By decreasing the number of biopsies of benign lesions and thereby substantially reducing costs, this approach may help overcome a major barrier to widespread use of mammographic screening.     

Ultrasonography of malignant breast neoplasms. Analysis of carcinomas missed as tumor.

PURPOSE: To analyze the malignant breast neoplasms missed as tumor on ultrasonography (US). MATERIAL AND METHODS: A total of 355 malignant tumors were confirmed at histology among 2,985 consecutive patients who underwent breast US. There were no prospectively recorded mammographic findings in 28 of the 355 tumors. The remaining 327 tumors included 16 ductal carcinomas in situ (DCIS) and 66 invasive carcinomas with suspicious microcalcifications on mammography. Excluding these 82 tumors because US would not have been indicated using strict criteria, a subpopulation of 245 noncalcified invasive malignant tumors remained for analysis. The neoplasms missed as tumor on US were analyzed for the whole tumor group (n=355) and the subpopulation (n=245). RESULTS: 42 (11.8%) of the 355 malignant neoplasms were missed as tumor on US, including 6 (2.5%) of the 243 palpable and 36 (32.1%) of the 1 12 nonpalpable malignancies. Most of the missed tumors were DCIS and microinvasive ductal carcinomas dominated by DCIS. In the subpopulation, 14 (5.7%) of the 245 malignancies were missed as tumor on US, including 4 (2.2%) of the 180 palpable and 10 (15.4%) of the 65 nonpalpable lesions. Of the 245 malignancies, 6 (2.4%) had a normal US finding, including 2 palpable retropapillary tumors and 4 incidental findings at histology. CONCLUSION: Using strict criteria for performing US as an adjunct to mammography, by far the most malignant breast neoplasms are diagnosed as a tumor on US.     

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.     

Role of mammography in women under 35 years of age

The detection of breast cancer in women under 35 is quite an uncommon event, accounting only for 3.2-3.4% of all breast cancers. To determine the indications for mammography in women under 35, the authors correlated clinical, mammographic, and US findings with fine-needle aspiration/surgical biopsy and follow-up results in 1040 symptomatic women examined at the Center of Senology of the Institute of Radiology-University of Perugia, Italy, from 1984 to June 1990. Of 1040 women, 482 (41.6%) had normal findings; benign disease was diagnosed in 558 (53.7%) cases, and malignant disease in 49 (4.7%). Mammography was very useful to diagnose malignancy in palpable breast lesions, as well as to suggest the need for biopsy, to detect metachronous cancers and to define lesion sizes. In inflammatory process--e.g., mastitis and abscesses--both mammography and US were capable of evaluating the real extent of the process, as well as its remission after therapy. Galactography had a specific role in the evaluation of the mammary duct and demonstrated intraductal pathologic conditions. In the authors' experience, mammography never showed occult breast cancers in women with no palpable breast lesions or hematic nipple discharge.     

Relationships between age, mammographic features and pathological tumour characteristics in non-palpable breast cancer

Non-palpable breast cancers are often in situ or smaller and have less nodal and distant metastases than palpable lesions. They represent a heterogeneous group of tumours, which may have different prognostic behaviour. We analysed a retrospective series of 982 non-palpable breast cancers assessed histologically at the National Cancer Institute of Milan from 1985 to 1995, following pre-operative mammography-guided localization. The association between mammographic data (parenchymal pattern and findings), patient age and tumour histology was investigated by review of clinical records and statistical modelling. We also investigated the association between the presence or absence of microcalcification as a mammographic finding and pathological tumour characteristics (tumour size, axillary nodes status and grading) or receptor status for oestrogen (ER) and progesterone (PgR). In situ disease or invasive tumour with an intraductal component, whether extensive or not, were commoner in young women and mammography more frequently showed a dense parenchymal pattern and microcalcifications in these cases. In older women (55 years or more), a fatty breast pattern, nodular opacities with or without microcalcifications, and invasive tumours of the ductal, lobular, mixed or other types were closely related. When the relationships between mammographic findings, pathological tumour characteristics and receptor status were investigated for invasive cancers, there was an association between the presence of microcalcifications and less favourable tumour characteristics.     

Breast cancers in women 35 years of age and younger: mammographic findings

During an 8-year period, 74 breast cancers were diagnosed in 66 patients 35 years of age and younger who underwent preoperative mammography. Mammograms and clinical data in these women were reviewed retrospectively to evaluate the mammographic findings and the efficacy of mammography. In 58 cases the cancer was detected by means of both clinical examination and mammography; in eight cases, mammography alone enabled readers to find the lesion; in seven cases, the lesion was found by means of clinical examination, but mammograms were negative; and in one case a cancer was found by means of incidental biopsy of the contralateral breast. Although 34 patients (52%) had dense breasts, mammography demonstrated the lesion in 66 cases (89%); the most common mammographic finding was microcalcifications, with or without associated masses (n = 28 [38%]). The authors do not suggest that screening of women younger than 35 years be performed routinely, but they believe that mammography can be valuable in screening young women at high risk for breast cancer or in confirming and suggesting prompt biopsy of a suspicious lesion.     

Ultrasound detection of nonpalpable mammographically occult malignancy.

OBJECTIVE: To evaluate the prevalence of occult malignancy with screening breast ultrasound. METHODS: All ultrasound-guided core needle breast biopsies performed between January 1, 1999, and June 30, 2001, were retrospectively reviewed. Lesions were identified during screening breast ultrasound in high-risk women with no mammographic or palpable abnormality in either breast, a unilateral mammographic or palpable abnormality in the contralateral breast, or a unilateral mammographic or palpable abnormality in a different quadrant of the same breast. All ultrasound-detected lesions were histologically verified. RESULTS: Six hundred and fifty-two women with a mean age of 49 years underwent 698 biopsies during the study period. Three hundred and forty-nine of these lesions were detected at screening breast ultrasound. Out of 349, 11 (3.2%) had a mammographically and clinically occult malignancy. Nine cancers were found in women with no mammographic or palpable abnormality. Two cancers were found in the same breast as the mammographic or palpable abnormality. None were found in the breast contralateral to a palpable or mammographic abnormality. CONCLUSION: Screening breast ultrasound of high-risk women has a similar detection rate for occult carcinoma as screening mammography, but has a low positive predictive value in cases where biopsy is performed.     

Radiologic aspects of breast cancers detected through a breast cancer screening program.

Early detection of breast cancer and reduced mortality in women with this disease is today attributed to the widespread use of mammography. High-quality performance is essential in every step of breast cancer screening programs in order to avoid unnecessary anxiety and surgery in the women concerned. This report presents the radiologic aspects of screening cancers. A total of 8370 asymptomatic women aged between 50-69 years were screened with 2-view mammography, of which only 70 (0.84%) were selected for surgery after a thorough work-up. Cancers were verified histologically in 61 women and 9 showed non-malignant histology, giving a cancer detection rate of 7.3 cancers per thousand screened asymptomatic woman. The benign/malignant ratio in the operated cases is thus approximately 1:7. The cancers detected showed all existing types of mammographic features where 77% (47 cases) showed rather typical findings, such as spiculated densities both with and without microcalcifications and with microcalcifications only. The remaining 23% (14 cases) showed parenchymal distortions, asymmetric and well-defined densities, both with and without calcifications. Our results indicate that surgery can be minimized without impairing the breast cancer detection rate. Radiologists in screening programs should be aware that a large proportion of non-palpable breast cancers present in rather unconventional forms. This point is important in order to maintain a high cancer detection rate and thereby justify the widespread use of mammography as a screening tool for breast cancer in asymptomatic women.     

Nonpalpable breast lesions: evaluation by means of fine-needle aspiration cytology

A prospective study was undertaken to assess the utility of fine-needle aspiration (FNA) cytology in women with nonpalpable suspicious microcalcifications or masses detected at mammography. Ninety-six breast lesions were aspirated during wire localization with standard mammographic technique. Cytologic results were compared with surgical pathology results. Sixty-one of the 96 aspirates were adequate for diagnosis. Nine were positive for malignant cells; seven, suspicious; 12, atypical; and 33, negative. All lesions demonstrating positive or suspicious cytologic findings were found to be malignant at biopsy; five of the 12 with atypical cytologic findings were malignant. Of 33 lesions deemed negative by means of cytology, two were biopsy-proved carcinomas. Cytologic examination permitted accurate diagnosis of 21 of the 23 (91%) carcinomas in which an adequate sample was obtained. Insufficient cellular material was obtained from 35 lesions, 16 of which showed marked fibrosis at histologic examination. The authors conclude that FNA cytology can aid in establishing a diagnosis in many cases in which nonpalpable breast lesions are detected at mammography.     

Tubular adenomas of the breast: imaging findings with histologic correlation

OBJECTIVE: The purpose of this study is to describe the imaging features of tubular adenomas, which are rare benign breast tumors usually found in women younger than 35 years old. CONCLUSION: In young women, tubular adenomas can look like noncalcified fibroadenomas on mammography and sonography. In older women, tubular adenomas may resemble malignant masses with microcalcifications. Awareness of these findings may help in assessing concordance between imaging and histologic findings after percutaneous core biopsy of these rare lesions.     

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.     

Mammography and echography in the study of breast prosthesis]

Between October 1990 and December 1991, the authors studied 58 women with breast implants (46 monolateral and 12 bilateral prostheses) by means of clinical examination, mammography, and US. The patients' age ranged 31-56 years (mean: 32). Thirty women had undergone subpectoral implantation, 22 subcutaneous and 18 retroglandular. In the group of subpectoral prostheses, 4 women had periprosthetic fibrosis and 3 presented benign calcifications; in 1 case both fibrosis and calcifications were observed. In the depiction of retroglandular implants, US appeared to be very useful: indeed, it detected 3 fibroadenomas and 5 cysts that had been missed at mammography. The only 2 breast carcinoma recurrences (1 non-palpable lesion, confirmed at surgery) were observed in patients with retrocutaneous prostheses. Both mammography and US currently play a major role in the follow-up of women with breast implants. Benign complications and breast cancers can be promptly detected even in patients with no palpable findings.     

Lobular carcinoma in situ: mammographic-pathologic correlation of results of needle-directed biopsy

The mammographic and histologic findings were reviewed in 41 consecutive cases of isolated lobular carcinoma in situ (LCIS) unassociated with any malignant diagnosis. Thirty-one needle-directed breast biopsies were performed to evaluate clustered microcalcifications. In 24 of the 31 cases, the calcifications were found in areas of benign breast disease, with LCIS representing a separate process. In the few cases in which microcalcifications were seen in association with LCIS, a greater number of similar calcifications were present in adjacent benign disease. Soft-tissue abnormalities necessitating the performance of a biopsy represented benign foci, except in one patient with LCIS in and adjacent to a fibroadenoma. The authors conclude that LCIS has no characteristic mammographic features. LCIS is detected as an incidental finding at breast biopsy, with the mammographic abnormality predominantly reflecting a benign process.     

Mammographic detection of recurrent cancer in the irradiated breast

Recurrence of cancer in the irradiated breast is an uncommon but potentially curable problem. Posttreatment mammograms were studied in 45 patients who had biopsies of an irradiated breast for suspected local recurrence to evaluate the usefulness of mammography in detecting such recurrences. Of 23 biopsy-proven recurrences, eight (35%) were detected by mammography only, nine (39%) were detected by physical examination only, and six (26%) were detected by both. Mammographic findings in recurrent malignancy included microcalcifications in six, microcalcifications associated with a mass in four, soft-tissue masses in three, and inflammatory changes in one. The results show that mammographic follow-up is complementary to physical examination in the detection of local recurrence in women who have undergone radiation therapy for early breast cancer.     

Benign breast lesions: ultrasound detection and diagnosis

Experience with 2500 patients over age 30 studied by physical examination, x-ray mammography, and sonography enabled definition of several specific clinical situations in which sonography adds meaningful diagnostic information not provided by either of the other examinations. These include: palpable breast masses for cyst-solid differentiation; nonpalpable mammographic masses for cyst-solid differentiation; and women with a symptomatic area in the breast that shows only uniformly dense fibro-glandular tissue on x-ray mammograms. For women with radiographically dense breasts who have no breast symptoms, abnormal physical findings, or mammographic lesions, sonography will identify many benign cysts and also some benign solid lesions, but at best only rarely (none of the 587 cases in this study) will it detect an otherwise occult breast cancer. Our data suggest that sonography should not be a substitute for physical examination and mammography in women over age 30, but rather that in three specific clinical situations it can be a valuable addition to the standard diagnostic evaluation.     

Comparative signal intensity measurements in dynamic gadolinium-enhanced MR mammography

Increases in signal intensity enhancement were measured in defined regions of interest (ROIs) to allow distinction between malignant and benign tumors with dynamic gadolinium-enhanced magnetic resonance (MR) mammography. Twenty patients with palpable breast lesions (15 malignant, five benign) underwent MR mammography. The dynamic gradient-echo sequence was performed with intravenous bolus injection of gadopentetate dimeglumine and consisted of 25 images with a time resolution of 30 seconds. Contrast enhancement was calculated by comparing user-defined ROIs on pre- and postcontrast images. An increase in signal intensity of 70% or more on the 1-minute postcontrast image was used as the criterion of malignancy. MR mammographic results correlated with histopathologic findings in all patients when the defined ROI was in the most enhancing part of the tumor. For the ROI in areas of submaximal enhancement or when the ROI surrounded the whole lesion, only five and nine tumors, respectively, fulfilled the malignancy criterion. All malignant tumors showed large variations in signal intensity enhancement that depended on the position of the ROI in the tumor. Dynamic, gadolinium-enhanced MR mammography allows distinction of benign from malignant breast tumors when the selected ROI is in the most enhancing part of the lesion.