Size, node status and grade of breast tumours: association with mammographic parenchymal patterns

A case-control study was designed to assess the association of mammographic parenchymal patterns with the risk of in-situ and invasive breast cancer. In addition, the relationship between tumour characteristics and mammographic patterns were also investigated. A total of 875 patients with breast cancer were selected and matched with 2601 controls. Mammographic parenchymal patterns of breast tissue were assessed according to Wolfe's classification, and statistical analysis was by conditional logistic regression. Relative to the N1 pattern, the odds ratios of having an invasive breast cancer associated with the P2 and DY patterns were 1.8 and 1.4, respectively. In addition, the odd ratios of having an invasive grade 3 breast cancer associated with the P2 and DY patterns were 2.8 and 3.9, respectively. Relative to the combined N1/P1 pattern, the odd ratios of having a breast cancer smaller than 14 mm, 15–29 mm, or larger than 30 mm associated with the combined high-risk P2/DY pattern (P2 + DY) were 1.2, 1.6, and 2.0, respectively. Finally, women with the P2/DY pattern were twice as likely to have a breast cancer which had already spread to the axillary nodes, compared to women with women with the N1/P1 pattern (odds ratios of 2.1 and 1.4, respectively). Our results confirm previous findings suggesting that mammographic parenchymal patterns may serve as indicators of risk for breast cancer. Our results also suggest that mammographic parenchymal patterns are associated with the stage at which breast cancer is detected. Received: 22 March 1999; Recieved after revision: 22 July 1999; Accepted: 27 July 1999     

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)     

Is the presence of mammographic comedo calcification really a prognostic factor for small screen-detected invasive breast cancers?

AIM: It has been suggested that the use of traditional prognostic factors such as histological grade and lymph node stage are not reliable predictors of outcome for small (<15 mm diameter) screen-detected breast cancers. It has also been suggested that the presence of mammographic comedo (casting) microcalcifications may be an important prognostic factor. We have determined prognostic factors for small screen-detected cancers in a univariate and multivariate fashion. MATERIALS AND METHODS: Histological grade, lymph node stage, invasive tumour size and vascular invasion status was obtained on 161 consecutive patients with primary invasive breast cancer <15 mm diameter, detected by screening. The Nottingham Prognostic Index was calculated for each patient. The mammograms were assessed for the presence of microcalcifications, these being classified as either comedo or non-comedo. Survival data was also obtained. RESULTS: Overall survival in this group of patients was excellent with only 12 patients (7.5%) dying from their breast cancer (mean follow-up 7.5 years). Univariate analysis showed a significant association between lymph stage and outcome (chi(2)=9.68, P=0.008). No significant association was demonstrated between the presence of comedo calcification and survival. Multivariate analysis confirmed lymph node stage as the only independent prognostic factor for these small screen-detected breast cancers (chi(2)=7.18, P=0.007). There were significant associations between the presence of comedo calcification on the screening mammogram and high histological grade and small tumour size. CONCLUSION: Although the overall outcome for small screen-detected breast cancers (<15 mm diameter) is excellent, the presence of lymph node metastases is associated with a significant reduction in long-term survival. The presence of mammographic comedo calcification is not an independent prognostic factor, but is closely related to histological grade.     

Tumour characteristics and survival in patients with invasive interval breast cancer classified according to mammographic findings at the latest screening: a comparison of true interval and missed interval cancers

The aim of this study was to investigate whether different mammographic categories of interval cancer classified according to findings at the latest screening are associated with different distributions of prognostic factors or with different survival rates. The series consisted of all patients with invasive interval cancer detected from May 1978 to August 1995 (n = 544). The tumours were evaluated with regard to age, radiological category, interval between the latest screen and diagnosis and tumour characteristics at the time of diagnosis. We investigated possible relationships between the survival rate of patients with interval cancer and the interval between the latest screen and diagnosis, tumour characteristics and radiological category of the interval tumours. The study focused on comparison of patients with true interval and missed interval cancer. Women with mammographically occult tumours were younger than those in the other radiological categories. Comparisons of true interval cancers with overlooked or misinterpreted tumours showed equal distributions of age, tumour size, TNM stage and lymph node status. The overlooked or misinterpreted tumours showed significantly higher proportions of grade-I tumours (22 vs 11 %), tumours with low S-phase fraction (SPF; 44 vs 24 %) and oestrogen receptor (ER) positive tumours (72 vs 57 %). However, analyses of survival rates disclosed no clear differences between the two radiological categories. Radiological category and interval between the latest screen and diagnosis were not genuine predictors of the prognosis in patients with invasive interval breast cancer. No certain prognostic difference existed between true interval cancers and overlooked or misinterpreted interval breast cancers, despite higher proportions of grade-I tumours, ER positive tumours and tumours with low SPF in the latter group. Received: 17 December 1997; Revision received: 6 May 1998; Accepted: 27 May 1998     

Mammographic findings after breast cancer treatment with local excision and definitive irradiation

Following local excision and definitive irradiation of 163 breast cancers in 160 women, alterations in mammographic patterns were observed for up to 7 years. Skin thickening was observed in 96% of mammograms obtained within 1 year of completing therapy and was most pronounced in women treated with iridium implant, chemotherapy, or axillary dissection. In 76% of mammograms, alterations in the parenchymal pattern, including coarsening of stroma and increased breast density, were seen at 1 year. Neither skin nor parenchymal changes progressed after 1 year. Within 3 years of treatment the parenchymal density, which usually regressed, did not change in all patients. At 3 years skin thickness and the parenchymal pattern had returned to normal in less than 50% of the breasts of these women. Scars developed in approximately one-quarter of women. They were present on the initial post-treatment mammogram and remained unchanged on serial studies. Coarse, benign calcifications also developed in the breasts of about one-quarter of women. Microcalcifications developed in 11 breasts; biopsy specimens of six were benign. Benign microcalcifications may be related to therapy.     

Preoperative estimation of the pathological breast tumour size by physical examination, mammography and ultrasound: a prospective study on 105 invasive tumours

OBJECTIVE: The clinical breast tumour size can be assessed preoperatively by physical examination, mammography and ultrasound. At present it is not clear which modality correlates best with the histological invasive breast tumour size. This prospective study aims to determine the most accurate clinical method (physical examination, mammography or ultrasound) to predict the histological invasive tumour size preoperatively. METHODS AND PATIENTS: Between October 1999 and August 2000, 96 women with 105 invasive malignant breast tumours were included in this study. All patients underwent excision and the tumour size was measured on histology. Tumour size was measured by all three modalities in 73 cases. Results were evaluated by calculating correlation coefficients. The examination modalities presenting the best estimation of the pathological tumour size were used in a stepwise linear regression analysis to construct a formula predicting the pathological tumour size from the result of the various diagnostic modalities. RESULTS: The correlation coefficient between ultrasound and pathological size (r=0.68) was significantly better than the correlations between physical examination and pathological size (r=0.42) and mammographic and pathological size (r=0.44). Physical examination overestimates and ultrasound underestimates breast tumour classification. The most accurate prediction formula was: Pathological tumour size (mm) equals sonographic tumour size (mm)+3 mm. CONCLUSION: When comparing physical examination, mammography and ultrasound for the prediction of the pathological size of a malignant breast tumour, ultrasound is the best predictor. The ensuing regression formula determines pathological size as tumour size by ultrasound+3 mm. However, with the wide 95% confidence interval of +/-11 mm, it remains difficult to predict the exact pathological size for an individual invasive breast tumour. A small deviation in millimetres of the tumour size could lead to a change in treatment and to another prognostic estimate.     

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).     

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.     

Factors associated with mammographic parenchymal patterns

The relationship between mammographic parenchymal patterns and known risk factors for breast cancer was studied in 5319 consecutive women presenting for breast screening. Using a multivariate analysis, correlations were found in pre-menopausal women between breast size, weight, age at first pregnancy, history of biopsy and history of cyclical breast pain and parenchymal pattern. In post-menopausal women the parenchymal pattern correlates with breast size, weight, weight change, age at first pregnancy, a history of biopsy and a history of breast feeding. The DY pattern correlated with age, breast size, weight, history of biopsy and menopausal status. When pre-menopausal women were considered separately the DY pattern correlated only with weight and breast size.     

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.     

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.     

Breast-conserving therapy in young women with invasive carcinoma of the breast

Higher local recurrence rates have been reported in young women with invasive carcinoma of the breast treated with breast-conserving therapy (BCT). However, age itself may not be responsible for this increased risk of recurrence. To investigate this further, a computerized literature search of MEDLINE was performed using data from 1996 to May 2003. The research was limited to female patients with localized, invasive adenocarcinoma of the breast but also included patients of young age with ductal carcinoma in situ. Women of young age with breast cancer, treated with BCT are at an increased risk of recurrence ranging from 7.5 to 35%. However, the data would suggest that the increased risk is secondary to the association of young age with more aggressive tumours and a positive family history of breast cancer. Other factors that may explain the adverse prognosis in women of a young age include associated genetic abnormalities and the lack of mammographic screening programmes for women of young age. Young age is a risk factor for breast recurrence after BCT. However, management decisions should be based on tumour stage, grade and other related prognostic features rather than on young age alone.     

Nonpalpable breast cancer: mammographic appearance as predictor of histologic type.

PURPOSE: To investigate the association between mammographic appearance and histologic diagnosis of nonpalpable breast cancers. MATERIALS AND METHODS: Mammographic characteristics of 317 consecutive clinically nonpalpable breast cancers in patients treated with breast-conserving surgery were reviewed. Malignant lesions were categorized as spiculated masses, other lesions, calcifications, and combined findings. Calcifications were characterized as amorphous, pleomorphic, or fine linear and branching. Logistic regression was used for the evaluation. Odds ratios (ORs) represent the magnitude of the association between a histologic diagnosis and a mammographic finding. RESULTS: Spiculated mass without calcifications (n = 150) and calcifications alone (n = 79) accounted for three of four cancers. A spiculated mass without calcifications was strongly associated with invasive cancers (OR = 12). Calcifications alone were strongly associated with ductal carcinoma in situ (DCIS) (OR = 19). In a decreasing order, the following invasive cancers were each associated with spiculated lesions without calcifications: ductal carcinoma grade 1 (OR = 28), ductal carcinoma grade 2 (OR = 17), lobular carcinoma (OR = 11), and ductal carcinoma grade 3 (OR = 4.6). Fine linear and branching calcifications alone were associated with not only DCIS nuclear grades 3 (OR = 17) and 2 (OR = 9.7) but also with invasive ductal carcinoma grade 3 (OR = 13). CONCLUSION: Mammographic appearance can be a predictor of histologic diagnosis in three of four nonpalpable breast cancers.     

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.     

Breast cancer: reliability of mammographic appearance as a predictor of hormone receptor status.

The association of mammographic appearance with hormone receptor status was investigated in 397 patients with primary breast cancers. The mammographic appearance was classified as type 1, spiculated (n = 159); type 2, structural changes (density) (n = 102); type 3, calcifications (n = 30); type 4, circumscribed opacity (n = 65); and type 5, not visible on mammogram (n = 41). Univariate analysis showed a significant association with estrogen receptor (ER) status for age (less than 50 vs greater than or equal to 50 years), tumor TNM category (those in category 1 vs those in higher categories), and mammographic appearance; with progesterone receptor status, the association was significant only for age. Multivariate analysis adjusted for potential confounders confirmed a significant association between ER status and mammographic appearance (ER status was more likely with type 1 than with the other mammographic types), but the strength of the association was limited. The mammographic appearance of breast cancer is not a reliable method to predict hormone receptor status for clinical purposes.     

Stereotactic 14G core biopsy of non-palpable breast cancer: what is the relationship between the number of core samples taken and the sensitivity for detection of malignancy?

AIM: Percutaneous 14-gauge core biopsy (CB) guided by digital stereotactic mammography is now an established technique in the investigation of women with non-palpable suspicious mammographic lesions. Diagnostic sensitivity of CB is affected both by the nature of the mammographic abnormality and by the number of core samples taken. METHODS AND RESULTS: A retrospective review of 500 women who have undergone CB in our institution showed that in 235 cases, invasive or non-invasive carcinoma was found on final surgical histology. Correlation between CB result and surgical histology revealed a significant increase in sensitivity for the diagnosis of malignancy if a larger number of cores were taken (84.3% for two cores and 90.2% for five cores vs. 97.9% for six or more cores). This trend was maintained when patients were subdivided according to mammographic abnormality, either soft tissue mass or microcalcifications. The effect on diagnostic sensitivity of increasing the number of tissue cores obtained was most pronounced in patients with microcalcifications graded as low or moderately suspicious for malignancy (70.1% for two cores and 79.1% for five cores vs 94.0% for six or more cores). The presence of an invasive component in a malignant lesion was correctly diagnosed using CB in 79.2% overall if at least six cores were taken. If the mammographic lesion was a soft tissue mass, this figure rose to 95.7%, but was only 35.7% if the visible lesion was composed of microcalcifications alone. CONCLUSION: Our series confirms the reliability of stereotactic CB in the diagnosis of breast carcinoma. Diagnostic sensitivity is improved by increasing the number of cores taken (to six or more), particularly in women with mammographic microcalcifications of an equivocal nature.     

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.     

Mammographic parenchymal patterns as risk indicators for incident cancer in a screening program: an extended analysis.

In a screening program of self-referred women, different mammographic parenchymal patterns were related to significantly different rates for developing breast cancer. The risk of cancer detection subsequent to a negative mammographic examination was 7.6 times greater for women in the highest parenchymal risk class compared with the lowest, an increase in risk comparable to that of a personal history of breast cancer and greater than that reported for any other combination of historical risk factors. These differences are qualitatively similar to, but of a lesser magnitude than, those in previous reports which were based on symptomatic women with previous negative mammograms. Data suggest this difference in risk is inherent between parenchymal patterns, rather than indicating difficulty in identifying small cancers in dense breasts. Findings of differential parenchymal risk, coupled with other risk factors, may lead to concentrating mammographic screening on a smaller segment of the population, thus improving the benefit-to-cost ratio.     

The correlation of mammographic-and histologic patterns of breast cancers in BRCA1 gene mutation carriers, compared to age-matched sporadic controls

Breast cancers in BRCA1 gene mutation carriers often have specific histologic features: grade III tumors with pushing margins. Our purpose was to compare the mammographic and histologic features of breast cancers in carriers with those in age-matched sporadic controls. The features of breast cancers in 27 BRCA1 carriers found during annual surveillance were compared to those in 107 age-matched sporadic controls. The carriers had no (classic) spiculated mammographic lesions, a high percentage of well-defined masses and hardly any masses with microcalcifications, whereas the controls had significantly fewer well-defined ones and only in 27% spiculated lesions on the mammogram. The well-defined mammographic tumors correlated in 83% of the carriers and in 70% of the controls with histologic circumscribed tumor margins. Spiculated mammographic lesions in the controls were in 90% grade I or II tumors. DCIS with or without infiltration was seen in 22% of the carriers and in 45% of the controls. In conclusion, breast cancers diagnosed in BRCA1 carriers do not have classic malignant mammographic features. A minority of the young sporadic controls show the classic malignant lesion on the mammogram. Both carriers and controls generally show a good correlation between their mammographic- and histologic tumor pattern.     

Mammographic parenchymal patterns and breast cancer risk. A case control study of a population-based screening experience

The authors investigated the association between mammographic parenchymal patterns and breast cancer risk by a case control study. Three-hundred and thirty-four cancers, either screen or interval detected in the course of a screening program, were assumed as cases and compared to 668 non-cancer controls matched by age, residence and date of screening examination. Parenchymal patterns were classified by retrospective blind review of randomly mixed films by two independent readers. A high agreement was achieved on a two-group scale (N1-P1 vs P2-DY) inter and intraobserver consistency being 0.94 and 0.95, respectively. The relative risk of breast cancer exposure (RR) with respect to N1 pattern was 1.99 for P1, 3.59 for P2 and 4.18 for DY patterns. The RR of P2-DY with respect to N1-P1 patterns was 2.62. The results did not change after stratification by age group. Parenchymal patterns do not seem to be a reliable criterion for selecting high risk women for screening as in this series only 57% of all cancers occurred in high risk (P2-DY) subjects.