早期乳腺癌的CR表现及病理基础

目的评价早期乳腺癌的CR表现及其病理基础。方法回顾性分析经病理证实的43例早期乳腺癌的CR片,包括导管原位癌及导管原位癌伴微浸润30例、浸润性导管癌12例和浸润性小叶癌1例,观察早期乳腺癌的CR表现,并与病理对照。结果(1)43例早期乳腺癌中,CR表现钙化21例(49%),结节15例(35%),非对称性局限性密度增高影伴结构紊乱7例(16%)。(2)乳腺数字化图像可以显示早期乳腺癌病变的细微结构。结论乳腺CR成像对早期乳腺癌的诊断具有重要意义。     

Invasive papillary breast carcinoma: mammographic and sonographic appearance

A retrospective study of the records of xeromammographic examinations of 940 patients with invasive carcinoma of the breast diagnosed during an 11-year period in an out-patient facility yielded four cases of invasive papillary carcinoma. In each of these four patients, xeromammography demonstrated multiple, round or oval, circumscribed areas of density in one quadrant of a breast. Sonographic examination of three patients showed the lesions to be solid. Two patients had previously had multiple benign intraductal papillomas, and one patient had had a solitary papilloma in the same breast. The possible association of invasive papillary carcinoma with previous multiple intraductal papillomas suggests that close clinical and radiographic monitoring of these patients may be necessary.     

Radiological appearances of papillary breast lesions

This review illustrates the varied appearances of benign and malignant papillary breast tumours, as identified by a breast cancer-screening programme. The commonest mammographic appearance of a papillary tumour is as a soft-tissue mass, with calcification present in less than half of cases. When calcification is present the pattern is variable, but clusters of pleomorphic calcification can occur, sometimes resembling the mammographic appearance of invasive ductal carcinoma. Ultrasonography of papillary lesions typically shows a solid, oval, intraductal mass, often associated with duct dilatation. A cystic component is also commonly seen, and lesions may appear hypervascular on colour Doppler ultrasound. Magnetic resonance imaging (MRI) has a high sensitivity, but low specificity for detecting papillary tumours, and is useful in establishing the extent and distribution of lesions in patients with multiple papillomatosis. Despite a benign histology on core biopsy, an argument exists for complete surgical excision of all papillary tumours, as a significant proportion of papillomas will contain foci of atypia or overt malignant change.     

Papillary lesions of the breast: evaluation with stereotactic directional vacuum-assisted biopsy.

PURPOSE: To evaluate the use of stereotactic directional vacuum-assisted biopsy (SDVAB) in diagnosing and managing papillary lesions of the breast. MATERIALS AND METHODS: The authors retrospectively reviewed the mammographic and histopathologic findings of 26 cases in which papillary lesions were diagnosed at SDVAB. In all cases, subsequent surgical excision (n = 20) or long-term imaging follow-up (n = 6) was performed and correlated with findings at SDVAB. RESULTS: SDVAB of 26 lesions yielded tissue that was classified as benign in 12, atypical in six, and malignant in eight. Of the 12 lesions that were diagnosed as histologically benign at SDVAB, six were surgically excised. Of these six lesions, five yielded benign correlative results. The sixth lesion was thought to be discordant with the imaging findings, and was surgically excised and determined to be malignant. Of the six benign lesions that were not surgically sampled for biopsy, five decreased in size and one was not seen at radiographic follow-up. Of the six lesions diagnosed as atypical at SDVAB that were surgically excised, one was benign and five were atypical. None proved to be malignant. Of the eight lesions diagnosed as malignant at SDVAB, surgical excision demonstrated ductal carcinoma in situ in all eight; two also had foci of invasive carcinoma. CONCLUSION: Benign and malignant papillary lesions of the breast can be reliably diagnosed at SDVAB when the SDVAB results correlate with the imaging findings. However, the extent of malignant papillary disease may be underestimated at SDVAB; in our study, invasive carcinoma was later discovered in 25% of patients with this diagnosis.     

钼靶X线征象与不同类型乳腺癌关系的病理基础研究

目的:探讨不同类型乳腺癌的X线表现与其病理基础之间的关系。方法:经乳腺X线检查,手术、病理证实的乳腺癌36例,共36个病灶,包括浸润性导管癌26个,导管内癌及导管内癌伴微浸润7个,浸润性小叶癌2个,黏液腺癌伴浸润性导管癌1个。观察乳腺癌的X线表现,与病理分型对照。结果:①癌灶的X线表现有肿块者23个(63.9%),有钙化者18个(50%),有结构扭曲者3个(8.3%);②呈肿块表现的以浸润性导管癌为主,占87.9%;有钙化者易出现在导管内癌和浸润性导管癌中,分别占87.5%、42.3%,尤其单纯钙化多出现在导管内癌中(71.4%,5/7);结构扭曲可见于浸润性导管癌和导管内癌中,其它类型未见。结论:肿块、钙化和结构扭曲为乳腺癌的主要X线表现。浸润性导管癌占乳腺癌的大部分,除单纯钙化首先考虑导管内癌,其余征象均首先考虑浸润性导管癌;肿块改变尚要想到髓样癌和黏液腺癌的可能;结构扭曲也可出现在导管内癌中。     

Local tumor recurrence following breast-conservation therapy: correlation of histopathologic findings with detection method and mammographic findings.

PURPOSE: To correlate histopathologic findings with detection method and mammographic appearance in primary and locally recurrent breast carcinoma after breast-conservation therapy. MATERIALS AND METHODS: Medical records and mammographic findings were retrospectively reviewed; 26 patients with 27 local recurrences after breast-conservation therapy were identified. RESULTS: Primary histopathologic findings included six in situ and 20 invasive carcinomas. Of the 27 recurrences, 19 (70%) were at or adjacent to the lumpectomy site and eight (30%) were elsewhere in the breast. All primary ductal carcinoma in situ (DCIS) cases manifested mammographically as microcalcifications and recurred as DCIS with microcalcifications. Eleven primary invasive carcinomas (10 masses, one case of microcalcifications) were detected only mammographically, three were detected only with physical examination, and six (six masses) were detected with both. Among these 20 recurrences, 14 (five masses, nine cases of microcalcifications) were detected only mammographically, one was detected only with physical examination, and five (five masses) were detected with both. Seventeen (85%) of 20 primary invasive carcinomas recurred invasively: 16 (94%) with similar histopathologic findings and eight (47%) with similar mammographic findings. CONCLUSION: In local recurrence after breast-conservation therapy for DCIS, histopathologic findings, detection method, and mammographic findings are usually similar. Histopathologic findings of primary invasive breast carcinoma and local recurrence are usually similar, but the detection method and mammographic findings vary. This is relevant to the interpretation of new clinical or mammographic findings following lumpectomy.     

Invasive lobular and ductal carcinoma: mammographic findings and stage at diagnosis.

The authors reviewed 316 cases of breast carcinoma diagnosed from January 1, 1986, to December 31, 1989. Clinical data and mammograms were available for all patients. Of the 316 carcinomas, 272 (86.1%) were invasive; 37 (13.6%) of these represented pure invasive lobular carcinoma (ILC). Twenty-five (68.5%) of the 37 patients with ILC and 161 (70.3%) of the 229 patients with invasive ductal carcinoma (IDC) presented with clinically palpable masses. Asymmetric opacities and architectural distortion were the predominant mammographic signs in 21 (57%) of the cases of ILC but only 32 (13.6%) of the cases of IDC. Malignant calcifications were not present in any of the patients with ILC but were present in 110 (47%) of those with IDC. Of the ILC lesions, 29 (85%) [corrected] had the same opacity as that of normal fibroglandular tissue, and the mammographic findings were often subtle and seen initially on one view only. There was no substantial difference in the TNM stage at diagnosis between the two study groups.     

Breast imaging findings in women with BRCA1- and BRCA2-associated breast carcinoma

AIM: To document the breast imaging findings of women with BRCA1 and BRCA2-associated breast carcinoma. MATERIALS AND METHODS: Family history clinic records identified 18 BRCA1 and 10 BRCA2 cases who collectively were diagnosed with 27 invasive breast carcinomas and four ductal carcinoma in situ (DCIS) lesions. All underwent pre-operative imaging (29 mammogram and 22 ultrasound examinations). All invasive BRCA-associated breast carcinoma cases were compared with age-matched cases of sporadic breast carcinoma. RESULTS: Within the BRCA cases the age range was 26-62 years, mean 36 years. Two mammograms were normal and 27 (93%) abnormal. The most common mammographic features were defined mass (63%) and microcalcifications (37%). Thirty-four percent of women had a dense mammographic pattern, 59% mixed and 7% fatty. Ultrasound was performed in 22 patients and in 21 (95%) indicated a mass. This was classified as benign in 24%, indeterminate in 29% and malignant in 48%. Mammograms of BRCA1-associated carcinomas more frequently showed a defined mass compared with BRCA2-associated carcinomas, 72 versus 36% (73% control group) whilst mammograms of BRCA2-associated carcinomas more frequently showed microcalcification, 73 versus 12% (8% control group; p < 0.001). Thirty-six percent of the BRCA2-associated carcinomas were pure DCIS while none of the BRCA1 associated carcinomas were pure DCIS (p = 0.004). Of those patients undergoing regular mammographic screening, 100% of BRCA2-associated carcinomas were detected compared with 75% of BRCA1-associated carcinomas. CONCLUSION: These data suggest that the imaging findings of BRCA1 and BRCA2-associated carcinomas differ from each other and from age-matched cases of sporadic breast carcinoma.     

Mammography in women with axillary lymphadenopathy and normal breasts on physical examination: value in detecting occult breast carcinoma.

OBJECTIVE. The purpose of this study was to determine the value of mammography in detecting occult carcinoma in patients with axillary adenopathy and normal breasts on physical examination. MATERIALS AND METHODS. We analyzed the results of mammography performed in 17 patients; all women had palpable axillary lymphadenopathy of unknown origin and all had normal breasts on physical examination. RESULTS. In 10 of the 17 patients, mammographic findings were abnormal. The mammographic finding of axillary adenopathy in seven patients was inconsequential because the nodes were evident on physical examination. Three patients had abnormal mammographic findings that were potentially significant, including one with a poorly defined mass suggestive of breast carcinoma, one with a subcutaneous nodule, and one with parenchymal breast edema. Two of 17 patients had an occult breast cancer. In only one of the patients was the cancer detected on mammography. The other patient had undergone prior left mastectomy and was thought to have metastases to the right axilla from the contralateral breast. Mammographic findings in this latter patient were normal. CONCLUSION. While occult breast carcinoma was relatively common in our series (two of 17 patients), the ability to detect the tumor with mammography was disappointing (one of two patients). This may be explained by the fact that one postmastectomy patient with occult carcinoma had metastatic disease to the contralateral axilla and a normal remaining breast, which was pathologically confirmed at mastectomy. Our experience suggests that mammography is valuable in patients with normal breasts on physical examination who have primary carcinoma involving ipsilateral axillary lymph nodes. The procedure should be included in the diagnostic evaluation of patients with axillary adenopathy in order to detect the unusual case of occult breast carcinoma.     

Mammographic predictors of the presence and size of invasive carcinomas associated with malignant microcalcification lesions without a mass

OBJECTIVE: Our objective was to determine the degree with which mammographic features predict the presence and size of invasive carcinomas associated with malignant mammographic microcalcification lesions without a mass. MATERIALS AND METHODS: Mammographic features were correlated with pathologic features in 304 consecutive breast carcinomas manifested by mammographic calcifications only in a prospective evaluation. RESULTS: Mammographic calcifications associated with breast carcinoma had the final pathologic diagnoses of pure ductal carcinoma in situ (DCIS) in 65% of patients, DCIS with a focus of invasion in 32%, and invasive carcinoma only in 4%. Invasive foci were more likely associated with mammographic calcification size of 11 mm and greater (40%, 77/194) compared with 1-10 mm (26%, 29/110; p = 0.019). Invasive foci were also more likely associated with linear calcifications (44%, 55/126) compared with granular calcifications (29%, 51/178; p = 0.007). The frequency of invasion did not increase with calcification extents greater than 10 mm. The frequency of invasion ranged from 22% for less than or equal to 5-mm granular calcifications to 45% for linear calcifications of 11 mm and greater. Only 11% of cancers characterized by fine granular calcifications were associated with invasion as compared with 32% of those with coarse and mixed granular calcifications (p = 0.002). CONCLUSION: Mammographic calcification features of malignant lesions cannot predict the absence of invasion with greater than 90% predictive value or predict the presence of invasion with greater than 45% predictive value. Increased extent of calcifications greater than 10 mm was not associated with greater likelihood of invasion.     

乳腺癌X线表现特征与C-erbB-2表达的相关性研究

目的:分析乳腺癌X线特征与C-erbB-2表达的相关性。材料和方法:回顾性分析经乳腺X线摄影以及手术病理证实的160个乳腺癌,将X线所见按照ACR创立并推荐的BI-RADS,分为肿块(大小、边缘、形态),钙化(分布、形态)进行描述,并与C-erbB-2的表达进行对照,分析其相关性。结果:乳腺癌C-erbB-2的阳性表达与单纯钙化有显著的相关性,C-erbB-2阳性表达的X线特征为单纯钙化。结论:乳腺癌X线表现的某些特征与C-erbB-2的表达具有显著的相关性,根据X线表现可以大概推测C-erbB-2的表达情况。     

Light scan evaluation of nonpalpable breast lesions

Transillumination light scanning of the breast was performed immediately before needle localization of 112 nonpalpable mammographic abnormalities detected in 103 patients. Twenty-four cancers were diagnosed in 23 patients. The positive predictive value for mammography was 21%. Ten (42%) of these nonpalpable cancers were not visible on transillumination light scanning. Eleven of 16 invasive ductal cancers and three of seven intraductal cancers were evident on transillumination light scans, but a single case of lobular carcinoma in situ was not evident. There were 12 false-positive light scan examinations. Transillumination light scanning had a 58% sensitivity, an 86% specificity, a 54% positive predictive value, and an 88% negative predictive value for small breast lesions. Therefore, the authors are unable to recommend delaying biopsy in patients with mammographic abnormalities on the basis of a negative light scan study.     

乳腺浸润性小叶癌和导管癌X线表现

本文回顾性总结206例浸润性乳腺癌,其中小叶癌24例,导管癌182例.通过对两组资料的分析对比,提出不对称致密影(37.5%),乳腺结构紊乱(25%)为浸润性小叶癌(ILC)的主要X线表现,而浸润性导管癌(IDC)则分别为5.5%和2.1%.结合文献简要讨论了有关小叶癌的X线的病理特点.     

Radiology-Pathology conference: papillary carcinoma of the breast

Papillary carcinoma of the breast is a rare breast carcinoma. It can be classified into invasive and noninvasive types. It can also be classified into intracystic and intraductal papillary carcinoma. Different radiological features are found to be associated with different histological types. Pitfalls are found to be associated with fine needle aspiration and core biopsy in the evaluation of papillary lesions. It is therefore important for radiologists to diagnose papillary carcinoma for proper management of the patients.     

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.     

Sonographic features of primary breast cancer in men

OBJECTIVE: The imaging studies of eight men with proven primary breast cancer and preoperative sonography and mammography were reviewed and correlated with final pathology reports. CONCLUSION: There were five cases of invasive breast carcinoma and three cases of ductal carcinoma in situ of the papillary subtype. All three cases of papillary ductal carcinoma in situ showed cystic features on sonography. Most (4/5) invasive cancers were solid on sonography. The appearance of a complex cystic mass in the male breast on sonography should suggest the possibility of malignancy and therefore warrants biopsy.     

Screening mammography-detected cancers: sensitivity of a computer-aided detection system applied to full-field digital mammograms

PURPOSE: To retrospectively evaluate the sensitivity of the performance of a computer-aided detection (CAD) system applied to full-field digital mammograms for detection of breast cancers in a screening group, with histologic findings as the reference standard. MATERIALS AND METHODS: This study had institutional review board approval, and patient informed consent was waived. A commercially available CAD system was applied to the digital mammograms of 103 women (mean age, 51 years; range, 35-69 years) with 103 breast cancers detected with screening. Sensitivity values of the CAD system according to mammographic appearance, breast composition, and histologic findings were analyzed. Normal mammograms from 100 women (mean age, 54 years; age range, 35-75 years) with no mammographic and clinical abnormality during 2-year follow-up were used to determine false-positive CAD system marks. Differences between the cancer detection rates in fatty and dense breasts for the CAD system were compared by using the chi(2) test. RESULTS: The CAD system correctly marked 99 (96.1%) of 103 breast cancers. The CAD system marked all 44 breast cancers that manifested as microcalcifications only, all 23 breast cancers that manifested as a mass with microcalcifications, and 32 (89%) of 36 lesions that appeared as a mass only. The sensitivity of the CAD system in the fatty breast group was 95% (59 of 62) and in the dense breast group was 98% (40 of 41) (P = .537). The CAD system correctly marked all 31 lesions of ductal carcinoma in situ (DCIS), all 22 lesions of invasive ductal carcinoma with DCIS, the single invasive lobular carcinoma lesion, and 45 (92%) of 49 lesions of invasive ductal carcinoma. On normal mammograms, the mean number of false-positive marks per patient was 1.80 (range, 0-10 marks; median, 1 mark). CONCLUSION: The CAD system can correctly mark most (96.1%) asymptomatic breast cancers detected with digital mammographic screening, with acceptable false-positive marks (1.80 per patient).     

Papillary lesions of the breast: diagnostic imaging and contribution of percutaneous needle biopsy with 14G needle

PURPOSE: To evaluate the presence of suggestive mammographic, US, color-Doppler, RM findings of 33 PLB and to show the accuracy of the large-core biopsy in evaluating these lesions. MATERIAL AND METHODS: A retrospective review of imaging-guided large-core biopsy of 860 consecutive lesions revealed that PLB were diagnosed in 31/33 cases and 3 were suspicious papillary lesions. Surgical correlation was available for all these lesions. Mammography and US were performed in all patients, Color-Doppler in 13/33 and MR in 10/33. RESULTS: Histological findings by percutaneous biopsy demonstrated 26 (79%) benign, 3 (9%) atypical, and 4 (12%) malignant lesions. Histological findings after surgery confirmed the diagnosis for benign and malignant lesions, while of the 3 atypical lesions, 1 was benign and 2 were malignant. One encysted papillary carcinoma in situ at core-biopsy was classified as invasive papillary carcinoma after surgery. PLB were usually found (52%) in subareolar location and the mean size was 17 mm (range 5-60 mm). The most frequent mammographic appearance of benign PLB was of a well-defined (71%), oval (53%) mass. The microcalcifications had variable features; they were isolated in 3/27 (15%) cases and associated with masses in 4/27 (20%). The mammographic finding of papillary carcinoma was of a well-defined (50%) or ill-defined, oval (50%) or lobulated (50%) mass, but never of a spiculated mass. US finding of the benign PLB most commonly showed a well-defined (84%), oval (84%), complex solid/cystic (52%) mass with frequently (60%) posterior enhancement. US finding of papillary carcinoma was of a well-defined (50%) or ill-defined (50%), oval (50%) or lobulated (50%) mass, most commonly solid-inhomogenous-hypoechoic. Color-Doppler showed high blood flow in 8/10 benign PLB and in 2/3 malignant PLB. Contrast-enhanced MR imaging demonstrated usually well-circumscribed, round masses (71%). The intensity/time curve showed marked focal enhancement (peak signal intensity over 70% at the first minute) in both benign and malignant lesions. DISCUSSION: Often the patients with PBL were symptomatic (for presence of nipple discharge or palpable mass). 31/33 papillary lesions identified at the subsequent imaging-guided large-core biopsy and in the 3/33 remaining lesions percutaneous core-biopsy required a subsequent surgical biopsy for the atypical papillary lesions. US proved to have the highest sensitivity, showing the suggestive feature of a frond-like mass within a dilated duct, and color-Doppler demonstrated high blood flow (which should be considered in differential diagnosis of galactocele). Mammographic finding of papillary lesions was often consistent with benign lesions (fibroadenoma, cyst). MR confirmed the high vascularization of these lesions, showing marked enhancement of the solid component. CONCLUSIONS: US, with Color-Doppler, proved to be the most useful examination for the identification and demonstration of the solid component of these lesions, which, observed further diagnostic investigation. As no definite mammographic, sonographic or RM pattern could be identified to differentiate between benign and malignant PLB, core-biopsy was required. Percutaneous biopsy has shown to be reliable in the diagnosis of benign and malignant PLB (without any false negative): infact, any atypical lesions require surgical examination. The framing of benign and malignant PLB with imaging and core-biopsy was useful because the frequent association of benign PLB with concurrent or subsequent breast carcinoma suggests surgical excision and radiological follow-up.     

Benign papillary neoplasms of the breast: mammographic findings

The clinical presentation, pathologic characteristics, and mammographic/ductographic (also known as galactographic) findings were reviewed in 77 patients with histologically proved benign papillary neoplasms of the breast. Patients were classified as having either solitary or multiple papillomas. Patients with multiple papillomas were further subclassified as having either central or peripheral papillomas. Fifty-one patients (66%) had solitary papillomas. Thirty-seven of these patients were symptomatic; 36 had spontaneous nipple discharge, and one had a palpable mass. Ductography was positive in 32 of the 35 patients who underwent the procedure. In the 14 asymptomatic patients, subareolar (n = 10) and peripheral (n = 4) mammographic abnormalities prompted biopsy. Fourteen patients (18%) had multiple peripheral papillomas, and one patient also had bilateral central solitary papillomas. Eleven of these patients were asymptomatic, while two presented with palpable abnormalities and one with spontaneous bilateral discharge. Mammographic findings included microcalcifications (n = 5) and clustering nodules (n = 2). Associated atypical ductal hyperplasia was found in six (43%) of the 14 patients with multiple peripheral papillomas. Some of these patients also had lobular carcinoma in situ and radical scars. Twelve patients had multiple central papillomas; all presented with spontaneous nipple discharge and had positive ductograms.     

Bilateral breast carcinomas: do they have similar mammographic features?

AIMS: This study compared the mammographic appearance, site and histological features of synchronous and metachronous bilateral breast carcinomas. METHODS: Site, type of abnormality and background pattern seen on the diagnostic mammograms of 63 women with bilateral breast carcinoma were compared. The histological type and grade of all the carcinomas were verified by histological review. RESULTS: There was a tendency for the contralateral tumour to have similar mammographic features to those of the initial tumour. In patients in whom the first carcinoma was visible purely as a mass, the contralateral carcinoma had a similar appearance in 82% (P < 0.001). When the original tumour showed mammographic calcification the contralateral tumour did so in 65% (P< 0.001). Normal mammography or calcification alone were seen almost exclusively in women with a dense background pattern (100% and 92% respectively) while masses and calcification with masses were seen in women with dense and fatty patterns (58% and 35% dense respectively). When the mammographic site of the contralateral tumour was compared with that of the first tumour no significant correlation could be demonstrated. There was a significant trend for contralateral carcinomas to be of the same histological grade (P < 0.005) but not histological type. CONCLUSIONS: Contralateral carcinomas often have a similar mammographic appearance to the first tumours. Two factors may be responsible: (i) the tendency for contralateral carcinomas to be of the same histological grade and (ii) the influence of mammographic background pattern on the radiological appearance of breast carcinoma. This knowledge may assist in the interpretation of follow-up mammography in patients with a previous breast carcinoma.