Extent Of Ductal Carcinoma In Situ Research Articles

Risk Reduction Strategies for Ductal Carcinoma In Situ

Ductal carcinoma in situ (DCIS) is a premalignant condition that, if left untreated, may progress to invasive breast cancer. After lumpectomy, DCIS can recur, and about half of recurrences are invasive. In 4 randomized trials, radiation has been shown to decrease the local recurrence rate by about half, though it does not change survival. Based on the results of 3 randomized trials, tamoxifen probably decreases cancer recurrence by about 30%, particularly in young women. Low fat diets, weight loss, and physical activity decrease invasive breast cancer recurrence and may be recommended to certain women with DCIS. Prognostic factors include age, extent of DCIS, margin status, grade, and presence of necrosis, although how these affect adjuvant therapy is unclear. Research evaluating other drugs to reduce recurrence risk and on different ways of delivering radiation continues.

Protocol for the Examination of Specimens From Patients With Ductal Carcinoma In Situ of the Breast

Authors Susan C. Lester, MD, PhD, FCAP* Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts Shikha Bose, MD, FCAP Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California Yunn-Yi Chen, MD, PhD, FCAP Department of Pathology, UCSF Medical Center, San Francisco, California James L. Connolly, MD, FCAP Department of Pathology, Beth Israel Deaconess Medical Center, Boston, Massachusetts Monica de Baca, MD, FCAP Physicians Laboratory, Sioux Falls, South Dakota Patrick L. Fitzgibbons, MD, FCAP Department of Pathology, St. Jude Medical Center, Fullerton, California Daniel F. Hayes, MD, Department of Medical Oncology, University of Michigan Medical Center, Ann Arbor, Michigan Celina Kleer, MD, FCAP Department of Pathology, University of Michigan Medical Center, Ann Arbor, Michigan Frances P. O’Malley, MD, FCAP Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, University of Toronto, Ontario, Canada David L. Page, MD, FCAP Department of Pathology, Vanderbilt University Medical Center, Nashville, Tennessee Barbara L. Smith, MD, PhD Department of Surgical Oncology, Massachusetts General Hospital, Boston, Massachusetts Donald L. Weaver, MD, FCAP Department of Pathology, College of Medicine and Vermont Cancer Center, University of Vermont, Burlington, Vermont Eric Winer, MD Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts Jean F. Simpson, MD, FCAP† Department of Pathology, Vanderbilt University Medical Center, Nashville, Tennessee For the Members of the Cancer Committee, College of American Pathologists

Measuring Extent of Ductal Carcinoma In Situ in Breast Excision Specimens: A Comparison of 4 Methods

Measuring the extent of nonpalpable ductal carcinoma in situ (DCIS) in a breast specimen is challenging but important because it influences patient management. There is no standardized method for estimating the extent of DCIS, although serial sequential sampling with mammographic correlation is considered an accurate method. To estimate the extent of DCIS using various methods and to compare these estimations with the extent as determined by the serial sequential sampling method. A total of 78 primary breast excisions with DCIS were retrospectively reviewed. All specimens had been sampled using the serial sequential sampling method, which involved mapping the location of each block on the sliced specimen radiograph and calculating the extent through 3-dimensional reconstruction. The other measures for estimating extent included (1) calculating size based on areas of calcification, (2) recording the number of blocks involved by DCIS and multiplying that number by 0.3 cm, and (3) measuring the largest extent of DCIS on a single slide. All 3 alternative methods tended to underestimate the DCIS. Discrepancies became more pronounced as size increased. The percentage of cases estimated to within 1 cm of the serial sequential sampling method were 81%, 72%, and 50%, respectively, for the calcification, blocks, and single-slide methods; differences of more than 2 cm were seen in 9%, 8%, and 30% of cases, respectively. The single-slide method performed poorly and should be used only when DCIS is limited to a single slide. Although the calcification and the blocks methods gave better estimates, both produced substantial underestimates and/or overestimates that could affect clinical decision making.

Measuring extent of ductal carcinoma in situ in breast excision specimens: a comparison of 4 methods.

Abstract Context.—Measuring the extent of nonpalpable ductal carcinoma in situ (DCIS) in a breast specimen is challenging but important because it influences patient management. There is no standardized method for estimating the extent of DCIS, although serial sequential sampling with mammographic correlation is considered an accurate method. Objective.—To estimate the extent of DCIS using various methods and to compare these estimations with the extent as determined by the serial sequential sampling method. Design.—A total of 78 primary breast excisions with DCIS were retrospectively reviewed. All specimens had been sampled using the serial sequential sampling method, which involved mapping the location of each block on the sliced specimen radiograph and calculating the extent through 3-dimensional reconstruction. The other measures for estimating extent included (1) calculating size based on areas of calcification, (2) recording the number of blocks involved by DCIS and multiplying that number by 0.3 cm...

The Role of Preoperative Magnetic Resonance Imaging for Detecting the Extent of Disease and Predicting the Prognosis of Ductal Carcinoma In Situ

Purpose: Magnetic Resonance Imaging (MRI) is widely used for the preoperative staging of breast cancer. In this study, we investigated a role of preoperative breast MRI for detecting the extent of disease and predicting the prognosis of ductal carcinoma in situ (DCIS). Methods: From January 2002 to April 2008, preoperative MRI was performed for evaluating the extent of disease in 26 patients with DCIS. The MRI findings, the modified Van Nuys scores and the clinicopathological results were reviewed. The accuracy of breast MRI was analyzed with respect to the detection of tumor multiplicity and disease extending into the nipple, and this was compared with that of mammography. Results: For detecting multiple lesions, the sensitivity and specificity of breast MRI were 25.0% and 86.4%, respectively, and the results of mammography were 0.0% and 86.4%, respectively. The accuracy of breast MRI was 76.9% and that of mammography was 73.1%. For detecting tumor extension into the nipple, the sensitivity and specificity of breast MRI was 100.0% and 80.0%, respectively, and that for mammography was 0.0% and 92.0%. respectively. The accuracy of MRI was 80.8% and that for mammography was 88.5%. The MRI final assessment was not associated with the modified Van Nuys score (p=0.474). Conclusion: For detecting the disease extent of DCIS, preoperative breast MRI is not superior to mammography due to the low specificity and accuracy of MRI. MRI did not show a definite ability to predict the prognosis of DCIS in this study.

Ductal Carcinoma in Situ: State of the Science and Roadmap to Advance the Field

Ductal carcinoma in situ (DCIS) is the fourth leading cancer for women in the United States. Understanding of the biology and clinical behavior of DCIS is imperfect. This article highlights the current knowledge base and the scientific roadmap needed to advance the field. This article is based on work done by and consultations obtained from leading experts in the field over a 6-month period that culminated in a full-day symposium designed to systematically review the most pertinent MEDLINE published reports and develop a roadmap to elucidate the molecular steps of carcinogenesis, reduce the extent or prevent the need for therapies, eliminate recurrences, and reduce morbidity. Expression profiling of pure DCIS will help elucidate the molecular characteristics that distinguish high-risk lesions from clinically irrelevant lesions. The development of new methods of extracting RNA from processed tissues may provide opportunities for research. Mammography often underestimates the pathologic extent of DCIS; other imaging methods need to be investigated for detection and monitoring of disease stability or progression. Novel biologic agents are being delivered in neoadjuvant clinical trials, and alternative methods for breast irradiation are being studied. Future trials of treatment versus no treatment for biologically selected cases of DCIS should be developed. There is a critical need for a concerted international effort among patients with DCIS, clinicians, and basic scientists to conduct the research necessary to improve fundamental understanding of the biology and clinical behavior of DCIS and prevent development of invasive breast cancer.

Ductal carcinoma in situ (DCIS) breast specimens need to be embedded completely in order to determine the correct extent of the disease

11061 Background: The processing of breast specimens suspicious of ductal carcinoma in situ (DCIS) is hampered by the fact that DCIS is not regularily visible at the gross level. There is no general consensus as how to process those breast specimens. Suggestions lead from examination of the entire tissue sample with a special focus on the resection margins to algorithms such as cutting only those paraffin blocks containing calcifications. Methods: In order to identify the influence of the diagnostic method on the measured extent of a DCIS lesion we compared two approaches. One was based on the examination of a single section and the other on examination of the entire specimen, i.e. cutting multiple 0.5 cm slices to be analyzed as max. 52 x 76 mm whole mount sections. 187 consecutive breast specimens from 186 patients (median patient age 60 years, range 31 to 87 years) from three gynecological institutions between Jan 2004 and Nov 2006 were searched for DCIS. We compared the largest tumor diameter from a single section of a specimen (‘apparent diameter‘, AD) with a ‘reconstructed diameter‘ RD calculated on the basis of the number of 0.5 cm slices taken from a sample and the number of slices containing the DCIS lesion. Results: Complete histological examination of these 187 cases (90 high and 97 low grade DCIS lesions) revealed a statistically significant difference (p=7.5E-9) between the apparent diameter AD (mean 22.4 mm, range 2 to 80 mm) and the reconstructed diameter RD (mean 31.6 mm, range 6 to 76 mm). In 138 cases (73.8%) the true extent of the disease would have been underestimated (RD > AD) if the diagnosis had been based only on a single exemplary section, the mean difference RD-AD being 14.8 mm (range 1–50 mm). In addition, we found 40 invasive cancers (multifocal inside the DCIS lesion, unifocal inside the DCIS and unifocal outside the DCIS). Conclusions: We conclude that the complete examination of a breast specimen helps to determine the true extent of DCIS and additionally helps to identify cases that turn out to be already invasive. Both findings may have important impact on the patients’ further treatment and outcome. No significant financial relationships to disclose.

Nonmammographic Evaluation of the Extent of Breast Carcinoma

The role of the breast imager has evolved beyond detecting breast cancer. With emphasis on management with breast conservation therapy, it has become imperative to image the patient preoperatively to adequately determine tumor size and to establish the presence or absence of multifocal, multicentric, or contralateral malignancy. The focus of this article was to provide a review of the current literature examining nonmammographic modalities available to the radiologist to thoroughly evaluate the newly diagnosed breast cancer patient. Our emphasis will be on breast ultrasound and magnetic resonance imaging (MRI). Specific topics discussed include the role, efficacy, and availability of these modalities in the assessment of ductal carcinoma in situ (DCIS) and invasive carcinoma. Mammography remains the standard for the evaluation of the extent of DCIS. However, ultrasound and MRI have been shown to be invaluable adjuncts in the evaluation of the patient with invasive carcinoma, especially those who are considering breast conservation therapy.

Contrast Enhanced MRI Findings of Ductal Carcinoma in Situ

Purpose: The purpose of this study is to describe characteristic contrast enhanced MR mammographic findings of ductal carcinoma in situ (DCIS) and also DCIS with microinvasion. Materials and Methods: From January 2000 to July 2005, 32 women with 33 lesions affected by DCIS or DCIS with microinvasion underwent contrast enhanced MRI, and they were then retrospectively evaluated. All the patients had previously undergone mammography and ultrasonography. All the findings of mammography, ultrasonography (US), and MRI were analyzed by using an ACR BI-RADS lexicon. Results: All 33 cases were enhanced on the enhanced MR images. A smooth margined homogeneous enhanced mass was seen in the two (2/33) cases, and nonmass enhancement was seen in 31 (31/33) cases. Among the non-mass enhancement, focal enhancement (7/31), ductal enhancement (5/31), segmental enhancement (9/31), and regional enhancement (10/31) were observed. On the kinetic study, a wash-out pattern (10/33), a plateau pattern (20/33), and a persistent pattern (3/33) were demonstrated. No significant differences were noted between the pure and microinvasive DCIS. Conclusion: There is no significant difference between pure and microinvasive DCIS. However, contrast enhanced MR images can demonstrate occult foci, multifocal lesion and the tumor extent of DCIS on mammogram or ultrasonogram.

Predictors of Residual Disease in Repeat Excisions for Lumpectomies with Margins Less Than 0.1 cm

Purpose This study sought to identify factors that would predict the presence of residual disease (RD) in repeat-excision specimens following an initial breast-sparing excision procedure in which the margins of resection were free of tumor but in which tumor was very close to ≥ 1 margins. Patients and Methods Ninety-one lumpectomies with close but not transected margins and their subsequent repeat-excision specimens were analyzed for tumor type near margin in the primary excision, presence of RD, type of RD, stage of infiltrating carcinoma (IC) in the primary excision, extent of ductal carcinoma in situ (DCIS), and grade of IC and/or DCIS. Results Nineteen of 91 patients had DCIS only; 15 had IC only; and 57 had IC with DCIS in their primary excisions. Thirty-five cases (38%) contained RD in their subsequent repeat-excision specimens. Residual DCIS and/or IC was present in 58% of patients whose primary tumors were DCIS only or invasive carcinoma < 6 mm (T1a), whereas invasive carcinomas ≥ 6 mm had RD in only 28%. Twenty-three patients (64%) with extensive DCIS had RD, whereas 12 patients (22%) with no DCIS or minor DCIS (< 10 mm) had RD (χ 2 = 16.27; P < 0.001). Ductal carcinoma in situ was within 0.1 cm of the margin in 52 patients, and RD was present in 26 (50%), whereas 18 of 56 patients (32%) with IC close to the margin had RD ( P < 0.05). Grade of DCIS and IC was not related to presence of RD. Residual carcinoma was present in 38% of repeat-excision specimens with close but not transected margins in this study. Conclusion The extent of DCIS in the primary specimen, DCIS near ≥ 1 margins, and size of infiltrating tumor were related to the presence of RD.

Nipple aspirate fluid cytology in breast carcinoma.

Nipple aspirate fluid (NAF) cytology is a simple noninvasive method to study cells exfoliated into the ductal system of the breast. In the current study, the significance of cytologic findings in NAF was determined by correlating them with histopathologic findings from corresponding breast tissue. Cytologic-histologic correlations of NAF were performed in only a few studies. Nipple aspirate fluid was collected by breast massaging and by using a breast aspiration device from 74 women with biopsy confirmed intraductal or invasive carcinoma with or without a history of preoperative neoadjuvant chemotherapy. Cytospin preparations were Pap stained. The number of epithelial cells was quantitated and foamy macrophages were semiquantitatively scored. Cytologic findings were categorized as insufficient for diagnosis (less than 10 epithelial cells), benign, mild atypia, marked atypia or suspicious, and malignant. Finally, they were correlated with tissue findings. Nipple aspirate fluid was obtained from 74 women, including 24 who had received preoperative neoadjuvant chemotherapy. The median age of patients was 54 years. A mean volume of 57 microL NAF and a mean of 149 epithelial cells were obtained. Foamy macrophages were present in 51 (70%) of the specimens. There was a significant correlation between the presence of epithelial cells and foamy macrophages (P < 0.001). Patients treated with chemotherapy had fewer epithelial cells in their NAF compared with patients who were not treated with chemotherapy. Thirty specimens (41%) were inadequate for diagnosis, 34 were (46%) benign, 5 (7%) were mildly atypical, 1 (1%) was markedly atypical, and 4 (5%) were malignant. Of the five cases with mildly atypical cytology, three were intraductal papilloma, one was low-grade papillary intraductal carcinoma, and one was low-grade intracystic papillary carcinoma with invasion in the corresponding tissue specimen. The single case with markedly atypical NAF cytology had extensive ductal carcinoma in situ (DCIS). Of the four cases with malignant NAF cytology, two were extensive DCIS and two had invasive carcinoma with extensive DCIS in the breast specimen. Overall, 3 (27%) of 11 cases of DCIS were detected in NAF and only 2 (4%) of 52 invasive carcinomas including the only two cases with extensive DCIS were detected in NAF. The probability of detecting malignant cells in NAF is dependent on the extent of DCIS and nipple involvement by DCIS. Nipple aspirate fluid is not a sensitive test for detecting invasive carcinoma of the breast. Atypical cytology in NAF is associated with papillary lesions in the underlying breast.

Extent of ductal carcinoma in situ within and surrounding invasive primary breast carcinoma.

The aim of this study was to evaluate the pathological and morphological features of ductal carcinoma in situ (DCIS) within and surrounding invasive ductal carcinoma, and to investigate its relationship with clinical outcome and established prognostic variables. One hundred and seven patients with primary operable invasive breast carcinoma and associated DCIS treated by simple or subcutaneous mastectomy or wide local excision with radiotherapy were assessed. Those with pure DCIS and insufficient tumour available for examination were excluded. The most representative haematoxylin and eosin-stained sections from the remaining 91 samples were selected and examined at x 100 magnification using a 45-point, 2-mm grid graticule. The entire section was assessed and the cell under each point of the graticule was classed as either normal (a), DCIS surrounded by normal tissue (b), invasive tumour (c) or DCIS surrounded by invasive malignancy (d). The volume ratio of DCIS in the normal (b/(a + b)) and invasive (d/(c + d)) tissue was then calculated. The DCIS volume within invasive tumour was not associated with outcome. The DCIS volume within adjacent normal tissue, however, was associated with local recurrence (P = 0.025), disease-free interval (P = 0.048), the occurrence of distant metastases (P = 0.019), death (P = 0.049) and disease-free survival (P = 0.048). Volume ratios of DCIS in normal and invasive tissue were not related to known prognostic factors including lymph node stage, grade, tumour size, vascular invasion or patient age. There is a significant prognostic effect relating to the extent of DCIS associated with an invasive cancer, particularly with respect to local recurrence of tumour. This effect is restricted to the volume of DCIS in the tissue surrounding the invasive lesion rather than the intratumoral component.

Surgery and staging for ductal carcinoma in situ

<h2>SUMMARY</h2> Ductal carcinoma in situ (DCIS) occupies the gray zone between histologic patterns that indicate a higher risk of neoplasia in an individual and invasive cancer. Only gradually is treatment moving from a wide variety of surgical options based on a priori considerations to evidence-based decisions. The few clinical series of biopsy with long-term clinical follow-up (> 25 years) suggest that given sufficient time most DCIS will progress to an invasive cancer. Although many laboratories are evaluating molecular and genetic markers of progression, histologic grade summarizes well the rate of progression of these lesions. Complete surgical excision of DCIS essentially eliminates the problem. This is accomplished with total mastectomy, yet this therapy is too radical for the majority of patients with DCIS–now commonly diagnosed as small lesions found during mammographic screening. With the primitive nature of molecular imaging, we are left with a sampling of the surgical margins and radiographic search for microcalcifications as the only means of assuring that resections of a portion of the breast have completely eliminated the process. The fixed variables (extent of DCIS, grade of DCIS and age of patient) are integrated with the factors that can be controlled (margin of surgical excision, addition of irradiation or a SERM such as tamoxifen). A paradigm is suggested based on current evidence.

Predictive value of extent and grade of ductal carcinoma in situ in radiologically guided core biopsy for the status of margins in lumpectomy specimens

Aims The correlation between the extent and grade of ductal carcinoma in situ (DCIS) in a core needle biopsy of breast, and the presence of an extensive intraductal carcinoma component (EIC) or positive resection margins in a subsequent mastectomy, has not been adequately addressed in the literature. Materials and methods Seventy-eight core needle biopsies with mammography and mastectomy correlation (27 total mastectomies, 51 lumpectomies) were reviewed. The extent and grade of DCIS in the biopsies were determined and compared with the mammographic findings and the status of the EIC and margins in subsequent mastectomy specimens. Results Twenty-four cases of core biopsies with at least three foci of low-grade DCIS or at least two foci of high grade DCIS (group I) corresponded in large part to cases of mastectomy with a positive EIC (20/23 cases, or predictive value of 87%). Nine of 15 cases of lumpectomy in this group were associated with margins positive for or close to (less than 0.1 cm from) carcinoma. Thirty-three cases of core biopsies with one or two foci of low-grade DCIS or one focus of high-grade DCIS (group II) were associated with mastectomies with a limited extent of DCIS. Only four of 22 lumpectomy specimens in this group had margins positive for or close to carcinoma. Twenty-one cases of core biopsies without DCIS (group III) represented all five mastectomy specimens without DCIS, and 16 mastectomies with DCIS and negative EIC. None of the 14 cases of lumpectomy in this group had margins positive for carcinoma. The predictive value for EIC status may be even higher if mammographic findings are used in cases with a low number of foci (two foci of low-grade DCIS or one focus of high-grade DCIS in short biopsy cores). Conclusions There was a good correlation between the extent and grade of DCIS in core biopsies and the status of EIC in subsequent mastectomy specimens. Core needle biopsies with at least three foci of low-grade DCIS or at least two foci of high-grade DCIS are associated with a greater likelihood of positive or close margins in subsequent lumpectomies. Core biopsies without DCIS are associated with a greater likelihood of negative margins in subsequent lumpectomies.

Ductal Carcinoma In Situ with Microinvasion

: The natural history of patients with ductal carcinoma in situ (DCIS) and microinvasion is poorly defined and the clinical management of these patients, with particular reference to management of the axilla, has been controversial. Studies addressing this lesion have used highly varied and sometimes arbitrary criteria for the evaluation of microinvasion. At the Armed Forces Institute of Pathology, we have defined microinvasion as a single focus of invasive carcinoma ≤ 2 mm or up to three foci of invasion, each ≤ 1 mm in greatest dimension. Such minuscule invasive carcinomas are apparently rare, accounting for considerably less than 1% of cases of breast carcinoma reviewed in consultation at our institution. To determine the frequency of axillary lymph node metastases associated with this lesion, we retrospectively reviewed 38 cases of DCIS with microinvasion (n= 29) or probable microinvasion (n= 9), all treated with mastectomy and axillary node dissection between 1980 and 1996. The foci of microinvasion ranged from 0.25 to 1.75 mm (mean 0.6 mm) in greatest dimension and were present adjacent to DCIS in 95.3% of cases. The extent of DCIS did not correlate with the number of foci of microinvasion. Axillary node dissections yielded a mean of 19.3 lymph nodes (range 7-38) and all lymph nodes were negative for metastatic tumor. None of 33 patients, followed for a mean of 7.5 years (range 1.0-14.4 years), developed local recurrence or metastasis. While the cases of microinvasive carcinoma evaluated in this study were not associated with axillary node metastases and appear to have an excellent prognosis, further study is indicated to determine the appropriate management and long-term prognosis of patients with this lesion.

Amplification units and translocation at chromosome 17q and c-erbB-2 overexpression in the pathogenesis of breast cancer.

Hyperplasia without and with atypia is considered to be a precursor lesion for certain breast carcinomas. The cytogenetic events and the molecular pathology involved in the multistep process from normal to invasive carcinoma are unknown. To characterise the sequence of early genetic abnormalities of chromosome 17q and their biological consequences in the pathogenesis of breast cancer, we performed immunohistochemistry on 451 breast tissues including 180 normal breast specimens, 28 hyperplastic lesions without atypia and 44 with atypia, 100 cases of ductal carcinoma in situ (DCIS) and 99 cases of invasive ductal carcinoma. We correlated the overexpression of the c-ErbB-2 protein, the histological and the recently proposed differentiation classification of DCIS with the extent of DCIS. For fluorescence in situ hybridisation (FISH) analysis, different probes spanning the 17q region including the c-erbB-2 gene locus and those which are found adjacent, were used. Reverse painting and comparative genomic hybridisation (CGH) were performed on several breast cancer cell lines. c-ErbB-2 overexpression was observed in only 29% of DCIS and 23% of invasive carcinomas, but not in hyperplastic and normal tissue. c-ErbB-2 overexpression is correlated with poor differentiation in DCIS but not in invasive carcinoma. In DCIS, there was no correlation with the histological subtype classification. The average extent of DCIS is significantly increased from 13.81 mm in c-ErbB-2 negative cases to 29.37 mm in c-ErbB-2 positive cases. The increase was considered to be a possible consequence of the overexpression and is probably due to the previously described motility enhancing effect of the c-ErbB-2 protein. The histological and differentiation classification of DCIS did not correlate with the extent of disease. Using FISH, amplified genes at 17q12, always including the c-erbB-2 gene, were detected in all cases of DCIS and invasive carcinoma with c-ErbB-2 overexpression. The centromeric region and the NF1 locus, which is located between the centromere and c-erbB-2, were not amplified in any of the DCIS and invasive breast carcinomas, but co-amplification of the myeloperoxidase gene was detected in 3/5 DCIS and 1/5 invasive carcinomas with c-ErbB-2 overexpression. In contrast to c-erbB-2, immunohistochemical overexpression of their respective gene products was not observed. FISH, reverse painting and CGH show similar amplified genes with amplified c-erbB-2 in c-ErbB-2 overexpressing SK-BR-3 and BT474 human breast cancer cells. The amplified genes are part of two different amplicons. Extensive modifications of the 17q chromosomal region, caused by translocation, were also observed in these cell lines. It is concluded that the modifications of chromosome 17q, inducing overexpression of c-ErbB-2 protein, occur at the level of transition from hyperplasia to DCIS. They are preserved in invasive carcinoma with overexpression of c-ErbB-2 protein. This had led to the hypothesis that these modifications at 17q may lead to a larger extent of DCIS.