Long term outcome of small size invasive breast carcinomas independent from angiogenesis in a series of 685 cases

BACKGROUND

To document the role of neoangiogenesis in the progression of breast carcinomas, intratumoral vascular density (ITVD) was assessed and compared to pathologic data and disease outcome in a series of 685 cases.

METHODS

Patients were registered between 1981 and 1988 at the Curie Institute. Tumors corresponded to small size (< or = 30 mm) invasive carcinomas, 71% of which were axillary lymph node-negative. In all cases, conservative surgery was the initial therapeutic procedure. The median follow-up was 10.8 years. ITVD was retrospectively determined as the number of immunostained (anti-F8RA/vWF antibody) vessels in an area of 1.2 mm(2). The prognostic value of ITVD regarding overall survival, locoregional recurrence-free, and metastasis-free intervals was assessed in uni- and multivariate analyses.

RESULTS

Microvessel count ranged from 5--245 per 1.2 mm(2) field. The median value was 62, and the mean was 67. The median was chosen as a cut point for statistical analysis. ITVD was found to be inversely linked to tumor size (P < or = 0.0001) and histologic grade (P = 0.005), and directly linked to vascular invasion (P = 0.02). In uni- and multivariate analysis, no significant link was found between ITVD and disease outcome, even after adjustment on histologic grade and tumor size.

CONCLUSIONS

ITVD was inversely correlated to tumor size and histologic grade in our series of small-size breast carcinomas. No significant link between ITVD and disease outcome was observed. Evaluation of the role of angiogenesis in tumor progression should be based on the discriminative assessment of mature and/or activated vessels.

Critical clinicopathologic analysis of 23 cases of fine-needle breast sampling initially recorded as false-positive. The 44-year experience of the Institut Curie

BACKGROUND

Because false-positive cytologic diagnoses in breast tumors are rare, few cases have been reported, although their consequences may be highly detrimental to the patient. The authors report the Institut Curie's experience, by using a multidisciplinary approach.

METHODS

Of 9334 benign breast tumors examined preoperatively for cytologic diagnosis by fine-needle sampling (FNS), the 23 (0.25%) FNS cases considered to be false-positive were retrospectively reviewed and analyzed.

RESULTS

Tumors were situated close to the nipple in 7 cases and away from the nipple in 16 cases. Tumor stage was T0 for 1 case, T1 for 18 cases, and T2 for 4 cases. Radiologically, six tumors were classified as malignant, seven as indeterminate or suspicious, and nine as benign. Three of six tumors studied by flow cytometry were DNA aneuploid. Based on a multidisciplinary clinicopathologic review, 20 FNS cases were finally classified as false-positive, and the remaining 3 tumors with malignant FNS and subsequent benign histology were classified as true-positive, because local and/or metastatic progression was observed in the short term.

CONCLUSIONS

The authors' review suggests two categories of false-positive cases: the first in which cytologic benign patterns are overdiagnosed, and the second in which atypical morphologic criteria were present. Nevertheless, as shown by the malignant course in three cases, patients with malignant preoperative FNS and corresponding benign histology always require close clinical follow-up. Finally, surgical overtreatment rate could be decreased if all radiologically benign tumors with positive/suspicious FNS were subject to intraoperative frozen section examination.

[Breast chondrosarcoma: a case report and review]

Sarcomas of the breast are relatively rare and account for 1% of all primary malignant tumors of the breast. Only 4 cases of pure chondrosarcoma of the breast have been published. We report an additional case in a fifty-seven-year-old woman. Histological and immunohistological characteristics were similar to those described in other localizations. Differential diagnosis involves cystosarcoma phyllodes and breast metaplastic carcinoma with chondroid differentiation. The prognosis is likely to be the same as in other chondrosarcomas.

[Value of macroscopic analysis for authentification of axillary sentinel nodes detected by Patent Blue dye alone during breast cancer surgery]

Assessment sentinel node coloration by the patent blue dye technique during breast carcinoma surgery largely depends upon the surgeon. It would therefore be valuable to define a procedure to validate the quality of the surgical specimen. With this aim, we have analyzed a series of 141 cases of sentinel nodes and determined whether the blue color of the node persisted after formalin fixation and could be assessed by examination of the tissue blocks. The pathologist's macroscopic control confirmed blue coloring in 114/141 cases (81%). This rate was similar when the sentinel node was metastatic (82.5%) (40 cases) or non metastatic (81%) (101 cases). Checking the color of the lymph node is a simple method to verify the quality of the surgical specimen. This item should be included in the pathologist's report. Several mechanisms can account for the lack of coloring of true sentinel nodes.

High sensitivity and specificity of immunohistochemistry for the detection of hormone receptors in breast carcinoma: comparison with biochemical determination in a prospective study of 793 cases

AIMS

The hormone receptor (HR) status of breast cancer is an important prognostic factor and predictive parameter of the response to hormone therapy. Enzyme immunoassay (EIA) is currently the standard for determination of HR, but immunohistochemistry (IHC) represents a potentially useful alternative. We used IHC to determine HR status in a large prospective study and compared the results to those obtained by EIA. This study was designed to determine which technique should be used in daily practice in our institution which manages a large number of patients.

METHODS AND RESULTS

Oestrogen (ER) and progesterone (PgR) receptor status was evaluated in a prospective series of 793 infiltrating breast cancers by IHC in paraffin-embedded tissue sections, using antibodies 6F11 and 1A6, with a rigorous quality control of the methodology. ER were found to be significantly expressed in 81% of cases after IHC analysis and in 78% of cases by EIA. For PgR, the respective rates of positivity were 65% and 69%. The tumour HR level detected by either technique was significantly correlated with the value of tumour size, histological grade and S-phase fraction. A significant link was observed between the percentage of labelled cells after IHC analysis and the amount of protein detected by EIA. Critical analysis of discordance found that, in the group of invasive lobular carcinomas, the rate of HR positivity was higher with IHC (84%) than with EIA (45%) and that, in the overall population, IHC was more specific than EIA, since cases with nonrelevant positivity related to intraductal normal or neoplastic cells expressing HR could be discarded. The cost of IHC analysis was found to be about one-third of that of EIA.

CONCLUSIONS

IHC is more sensitive, specific and economical than EIA. It should constitute the new standard technique provided that good quality assurance procedures are respected.

Low expression of bcl-2 in Brca1-associated breast cancers

Little data are available concerning the molecular mechanisms of action of Brca1 and Brca2 in breast oncogenesis. Recent experimental results suggest that Brca1 plays a role in the regulation of apoptosis. In order to determine whether the analysis of human tumours would provide data supporting this hypothesis, we have assessed the expression of the antiapoptotic bcl-2 and of the proapoptotic p53 genes in Brca1 - and Brca2 -associated breast carcinomas. The levels of expression of these genes were compared to those observed in controls and to the mitotic and the apoptotic indexes. Our series were composed of 16 cases of breast carcinoma in women with a germline Brca1 gene mutation, and of four cases with Brca2 mutation. A group of 39 patients aged under 36 years and for whom the search for Brca1 gene mutations was negative, and a group of 36 cases of sporadic cancers without data on their Brca status were used as controls. Immunohistochemistry was used to detect p53 and bcl-2 gene products. Mitotic and apoptotic indexes were higher in Brca1 -associated tumours than in controls. No significant difference in p53 immunostaining was observed between the four groups of patients. In contrast, the rate of bcl-2 -positive tumours was lower (31%) in Brca1 -carcinomas than in carcinomas without Brca1 mutation (90%) (P< 10(-3)). A strong Bcl-2 expression was found in the four cases of Brca2 -associated carcinomas. No significant correlation was observed between p53 and Bcl-2 immunostainings, either in cases or in controls. The association between Brca1 status and Bcl-2 expression remained significant after adjustment for the oestrogen receptor status. Our study shows that a low expression of bcl-2 characterises most Brca1 -associated breast carcinomas, a biological trait which seems not to be shared by Brca2 -associated tumours nor to be related to oestrogen receptor and/or p53 status. bcl-2 might thus be one of the target genes involved in the oncogenesis related to Brca1 and its down-regulation may account for the increased apoptosis and the high proliferative rate observed in Brca1 -associated carcinomas.

Strong correlation between results of fluorescent in situ hybridization and immunohistochemistry for the assessment of the ERBB2 (HER-2/neu) gene status in breast carcinoma

ERBB2 (HER-2/neu) amplification and/or overexpression are associated with poor prognosis in node-positive breast carcinoma. Its prognostic value in node-negative cases and its predictive value for response to chemotherapy remain controversial. This may be related to the use of molecular methods, which are sensitive to dilution of tumor material by normal cells, or the use of nonstandardized immunohistochemistry (IHC) procedures, for the determination of the ERBB2 gene status. In addition, new therapeutic approaches that target the cells overexpressing ERBB2 are under development. These perspectives necessitate a reliable evaluation of the status of ERBB2 in individual tumors before the application of specific therapeutic strategies. Fluorescent in situ hybridization (FISH) and IHC allow the evaluation of the ERBB2 status specifically in tumor cells on archival material. We have analyzed a series of 100 invasive ductal breast carcinomas without lymph node invasion both by IHC, using the CB11 monoclonal antibody and a sensitive Auidin Biotin Complex (ABC) immunodetection system, and by FISH, using the Oncor Inform HER-21neu (ERBB2) gene amplification detection system as reference technique. Complete concordance between the results of FISH and IHC was seen in 98% of the cases. ERBB2 amplification (more than four signals per nucleus) was observed in 12 of the 100 cases, and all but one showed an overexpression of the protein (membrane staining) by IHC. Conversely, ERBB2 expression was present in one case without gene amplification. In conclusion, ERBB2 overexpression detected by IHC is highly correlated to gene amplification detected by FISH. Thus, under standardized conditions, IHC is a reliable and economical test to assess the ERBB2 status in tumors. The use of FISH could be limited to the verification of the status of tumors displaying a weak membrane immunostaining.

Causes of inconsistency in diagnosing and classifying intraductal proliferations of the breast. European Commission Working Group on Breast Screening Pathology

It is now widely recognised that classifying ductal carcinoma in situ (DCIS) of the breast and diagnosing atypical ductal hyperplasia are associated with significant interobserver variation. Two possible reasons for this inconsistency are differences in the interpretation of specified histological features and field selection where morphology is heterogeneous. In order to investigate the relative contribution of these two factors to inconsistent interpretation of intraductal proliferations, histological sections of 32 lesions were sent to 23 European pathologists followed 3 years later by images of small parts of these sections. Kappa statistics for diagnosing hyperplasia of usual type, atypical ductal hyperplasia and ductal carcinoma in situ were 0.54, 0.35 and 0.78 for sections and 0.47, 0.29 and 0.78 for images, respectively, showing that most of the inconsistency is due to differences in morphological interpretation. Improvements can thus be expected only if diagnostic criteria or methodology are changed. In contrast, kappa for classifying DCIS by growth pattern was very low at 0.23 for sections and better at 0.47 for images, reflecting the widely recognised variation in the growth pattern of DCIS. Higher kappa statistics were obtained when any mention of an individual growth pattern was included in that category, thus allowing multiple categories per case; but kappa was still higher for images than sections. Classifying DCIS by nuclear grade gave kappa values of 0.36 for sections and 0.49 for images, indicating that intralesional heterogeneity has hitherto been underestimated as a cause of inconsistency in classifying DCIS by this method. More rigorous assessment of the proportions of the different nuclear grades present could lead to an improvement in consistency.

[Standards, Options and Recommendations (SOR) for endocrine therapy in patients with non metastatic breast cancer. FNCLCC]

CONTEXT

The "Standards, Options and Recommendations" (SOR) project, started in 1993, is a collaboration between the Federation of the French Cancer Centres (FNCLCC), the 20 French Cancer Centres and specialists from French Public Universities, General Hospitals and Private Clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and outcome for cancer patients. The methodology is based on literature systematic review and critical appraisal by a multidisciplinary group of experts, with feedback from specialists in cancer care delivery.

OBJECTIVES

To develop clinical practice guidelines according to the definitions of Standards, Options and Recommendations for endocrine therapy in patients with non metastatic breast cancer.

METHODS

Data have been identified by literature search using Medline, Embase, Cancerlit and Cochrane databases - until july 1999 - and the personal reference lists of the expert group. Once the guidelines were defined, the document was submitted for review to 125 independent reviewers.

RESULTS

The main recommendations for the endocrine therapy of patients with non metastatic breast cancer are: 1) Endocrine therapy modalities depend on menopausal status or age of women: ovarian suppression for premenopausal women, antiestrogen drug therapy for postmenopausal women (standard). 2) Tamoxifen (20 mg/d - 5 years) is beneficial to women with positive estrogen receptor tumor (standard, level of evidence A). There is no indication of tamoxifen treatment for women with negative estrogen receptor tumor (standard, level of evidence A). 3) For postmenopausal women with positive estrogen receptor tumor, tamoxifen is the standard adjuvant treatment (level of evidence A). For postmenopausal women with negative estrogen receptor, adjuvant chemotherapy has to be considered (option, level of evidence A). No adjuvant treatment has to be considered for women with poor health condition (option). 4) For premenopausal women with estrogen receptor tumor, results of clinical trials of chemotherapy versus endocrine therapy, suggest a benefit for endocrine therapy. However, there is no sufficient evidence to consider endocrine therapy alone as a standard adjuvant treatment. 5) For premenopausal women, chemotherapy + ovarian suppression or chemotherapy + tamoxifen are not better than chemotherapy alone (level of evidence A). 6) For postmenopausal women, administration of chemotherapy plus adjuvant tamoxifen versus the same tamoxifen alone, is of additional benefit in reducing recurrences but not in prolonging overall survival (standard, level of evidence A). 7) Balance of known benefits (delay to recurrence and death) and risks (side-effects of therapy) for adjuvant chemoendocrine therapy has to be taken into consideration before decision making. Chemoendocrine therapy can be indicated for women at high risk of developing metastatic disease (recommendation, experts agreement).

ERBB2 overexpression in breast carcinomas: no positive correlation with complete pathological response to preoperative high-dose anthracycline-based chemotherapy

The predictive value of ERBB2 amplification/expression to doxorubicin use is controversial. Preoperative chemotherapy, followed by the pathological assessment of tumour response to treatment provide optimal conditions for the evaluation of the predictive value of biological parameters. We report here data on the predictive value of ERBB2 in a series of 54 cases of breast cancer treated by preoperative high-dose anthracycline-based chemotherapy. Our series consisted of 26 women presenting an inflammatory breast cancer (IBC) and of 28 women with poor prognosis primary cancer (PPPC). Patients received a total of four cycles with doxorubicin (75 mg/m(2) for IBC or 70 mg/m(2) for PPPC) and cyclophosphamide (6 g/m(2) for IBC or 1400 mg/m(2) for PPPC), every 21 days. ERBB2 expression was determined by immunohistochemistry (clone CB11) performed on a tumour biopsy taken before chemotherapy. All patients underwent surgery as a second step of treatment, and the tumour response was assessed on pathological specimens. A complete pathological response was observed in 24 of the 54 cases (44%) (95% confidence interval (CI), 31-57). Pathological complete response was positively correlated with high histological grade (P=0. 02) and with the absence of oestrogen (P=0.003) or progesterone (P=0. 02) receptor expression. ERBB2 overexpression was found in 18 of the 54 cases (33%). A complete pathological response was observed in 33% of these cases (6/18). This figure was not significantly different from the 50% rate of complete response observed for tumours with no detectable ERBB2 expression (18/36). In this small series, ERBB2 overexpression was not a significant predictive marker of the pathological response to high-dose doxorubicin-based chemotherapy.

[Standards, Options and Recommendations (SOR) for drafting of anatomic and surgical pathology reports or cytopathology reports in oncology]

CONTEXT

The "Standards, Options and Recommendations" (SOR) project, started in 1993, is a collaboration between the Federation of the French Cancer Centres (FNCLCC), the 20 French Cancer Centres and specialists from French Public Universities, General Hospitals and Private Clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and outcome for cancer patients. The methodology is based on literature review and critical appraisal by a multidisciplinary group of experts, with feedback from specialists in cancer care delivery.

OBJECTIVES

To develop practice guidelines according to the definitions of the Standards, Options and Recommendations project for the content of the anatomic and surgical pathology or cytopathology reports in field of oncology.

METHODS

Data were identified either by searching on Medline or via members of the expert groups personal references lists. When the guidelines were defined, the document was submitted to 49 independent reviewers, and to the medical committees of the 20 French Cancer Centres.

RESULTS

The main recommendations for the drafting of the anatomic and surgical pathology or cytopathology reports in oncology are: 1) The reports must contain the identification of the pathologist, of the patient and of the specimen, a gross description for the surgical specimen, eventually a microscopic description, the diagnosis, all the elements essential for establishing the prognosis and for the clinical care, and a conclusion. 2) The reports could contain some comments. 3) The reports must be brief, precise, clear, homogeneous and ideally standardised, in order to be comprehensible for all the clinicians and the pathologists.

[Spindle cell carcinoma of the breast with neuroendocrine differentiation. A rare entity simulating a benign tumor]

We report a case of spindle cell carcinoma of the breast with neuroendocrine and mucinous differentiation. Histological diagnosis can be difficult as macroscopic appearance and low grade cytologic features suggest a benign tumor. Differential diagnosis with a fusiform benign tumor of myoepithelial origin should be discussed. Immunohistochemistry is essential to confirm the diagnosis.

[Identification of sentinel lymph node in breast cancer: experience from the Institut Curie]

Sentinel lymph node (SN) biopsy is a recently developed, minimally invasive technique for staging the axilla in breast cancer. This new procedure of selective lymphadenectomy has been the subject of several studies, but there is not currently a consensus of opinion to define which is the best method of identification. At the Institut Curie since 1996, we have been using the Patent blue dye. The current series present the result of 122 patients with T1, T2, N0 or N1a breast cancer consecutively operated between december 1997 and august 1998. Sentinel nodes were identified in 107 out of 122 (87.7%) and accurately predicted axillary nodal status in 104 out of 107 (97.1%) cases. Three out of 35 node positive patients would have been missed with sentinel node biopsy alone, for a false negative rate of 8.5%. In all 3 cases, one lymph node presented with a micrometastases. In 15 cases out of 35 with metastatic axillary nodes, the only positive node was the SN (43%). The encouraging results of this study shows that it is possible to identify, in a large number of cases, the sentinel node by means of Patent blue dye only. This article detailed the technique used and reviews the literature concerning other methods of identification.

Immunoglobulin variable regions usage by B-lymphocytes infiltrating a human breast medullary carcinoma

Breast medullary carcinoma are heavily infiltrated by B-lymphocytes and associated with a good prognosis despite their high histological grade. We investigated the Ig repertoire of B-lymphocytes infiltrating one such tumour. A single cell suspension was obtained from a tumor specimen by enzymatic digestion. VH, Vkappa, and Vlambda regions were amplified by RT-PCR using mixtures of primers optimized to maximize the diversity of the PCR products. They were then cloned and sequenced. Analysis of 9 VH, 5 Vkappa, and 10 Vlambda sequences using the Kabat database indicated that several VH and VL region subgroups (I, II and III) are expressed by B-lymphocytes infiltrating this tumor. The analysis of CDR3 regions also showed a variability, although some VH and VL clones exhibited identical or nearly identical sequences. Thus, the B-cell infiltration observed in this breast medullary carcinoma does not reflect a monoclonal proliferation and represents an oligoclonal or a polyclonal B-cell proliferation.

[Conservative treatment of multifocal breast cancer: a comparative study]

Conservative treatment of multifocal breast cancer is still very controversial. This retrospective study concerns 56 patients with stage I or II multifocal breast cancer who underwent conservative treatment at the Institut Curie from January 1983 to December 1989. These patients (group 1) were matched with 132 patients with multifocal lesions treated by mastectomy (group 2). Surgical treatment consisted of a single wide lumpectomy followed by external radiotherapy. Adjuvant systemic therapy and regional nodal irradiation were administered as indicated by current protocols. The actuarial 5-year overall survival rate was 94% 6 in group 1, and 90% 6 in group 2 (NS). The actuarial 5-year ipsilateral breast recurrence rate was 11% 8 in group 1, and 11% 5 in group 2 (NS). In group 1 patients, the ipsilateral breast recurrence rate was related neither to type of multifocality nor to presence of intra ductal breast carcinoma, nodal status, tumor margins, radiotherapy boost, or distance between tumors. Consequently, conservative treatment of multifocal breast cancers which can be completely removed by a single lumpectomy seems, when technically feasible, an alternative to mastectomy.

Consistency achieved by 23 European pathologists from 12 countries in diagnosing breast disease and reporting prognostic features of carcinomas. European Commission Working Group on Breast Screening Pathology

A detailed analysis of the consistency with which pathologists from 12 different European countries diagnose and classify breast disease was undertaken as part of the quality assurance programme of the European Breast Screening Pilot Network funded by the Europe against Cancer Programme. Altogether 107 cases were examined by 23 pathologists in 4 rounds. Kappa statistics for major diagnostic categories were: benign (not otherwise specified) 0.74, atypical ductal hyperplasia (ADH) 0.27, ductal carcinoma in situ (DCIS) 0.87 and invasive carcinoma 0.94. ADH was the majority diagnosis in only 2 cases but was diagnosed by at least 2 participants in another 14, in 9 of which the majority diagnosis was benign (explaining the relatively low kappa for this category). DCIS in 4 (all low nuclear grade) and invasive carcinoma (a solitary 1-mm focus) in 1. The histological features of these cases were extremely variable; although one feature that nearly all shared was the presence of cells with small, uniform, hyperchromatic nuclei and a high nucleo-cytoplasmic ratio. The majority diagnosis was DCIS in 33 cases; kappa for classifying by nuclear grade was 0.38 using three categories and 0.46 when only two (high and other) were used. When ADH was included with low nuclear grade DCIS there was only a slight improvement in kappa. Size measurement of DCIS was less consistent than that of invasive carcinoma. The majority diagnosis was invasive carcinoma in 57 cases, the size of the majority being 100% in 49. The remainder were either special subtypes (adenoid cystic, tubular, colloid, secretory, ductal/medullary) or possible microinvasive carcinomas. Subtyping was most consistent for mucinous (kappa, 0.92) and least consistent for medullary carcinomas (kappa, 0.56). Consistency of grading using the Nottingham method was moderate (kappa=0.53) and consistency of diagnosing vascular invasion, fair (kappa=0.38). There was no tendency for consistency to improve from one round to the next, suggesting that further improvements are unlikely without changes in guidelines or methodology.

Homogeneously staining regions in 223 breast carcinomas: cytogenetic and clinicopathological correlations

A correlation analysis was performed on 223 breast carcinomas to assess the relationships between gene amplification, karyotypic and clinicopathological features. Homogeneously staining region (HSR) is the most frequent form of amplification found in breast cancer. HSR-containing tumours accounted for 60% of the cases. Although up to 40% of tumours with slightly altered karyotype contained HSRs, an excess of HSRs was found within the tumours whose karyotype showed the highest rates of rearranged chromosomes. HSRs were also found to be particularly frequent in small tumours of high histological grade and with a low expression of progesterone receptors. An excess of HSRs seems to be observed in younger patients, however, significant correlation could be demonstrated only for patients below 55 years and below 60 years, compared with older ones. With a 120-month follow-up for 152 patients, a significant association between the presence of HSRs and a shortened overall survival was observed. Altogether, the presence of HSRs appears to be a good indicator of poor prognosis. Further studies are needed to determine whether amplification of specific genes or cell ability to amplify is the most important parameter for tumour progression.

[Diagnostic difficulties and limits in breast histopathology in core biopsies (breast microbiopsies)]

Core biopsy is increasingly used for the diagnosis and management of breast lesions. As a result, pathologists are being confronted with new difficulties pertaining to (1) the histological diagnosis on micro specimens (2) the correlation between core biopsy histological findings and mammographic findings, (3) the diagnostic significance of atypical hyperplasia on core biopsies, (4) the impact of tissue displacement on surgical specimens after needling procedures, and (5) the disagreement that can appear between the diagnostic on surgical specimen and on core biopsy.

Consistency achieved by 23 European pathologists in categorizing ductal carcinoma in situ of the breast using five classifications. European Commission Working Group on Breast Screening Pathology

The increased detection of ductal carcinoma in situ (DCIS) by mammographic screening, the greater use of breast-conserving surgery, and the recognition that certain histological subtypes are associated with a greater risk of local recurrence has led to the formulation of several new classifications of DCIS in recent years. There are, however, no data concerning the degree of consistency with which these schemes can be applied by reasonable numbers of pathologists. Thirty-three cases of DCIS were thus examined by a working group of 23 European pathologists who categorized them using five recently published classifications: (1) that of the European Pathologists' Working Group based on differentiation (a combination of nuclear grade and cell polarization) with categories of poorly, intermediately, and well differentiated; (2) one based entirely on nuclear grade with categories of high, intermediate, and low, currently in use in the UK national and EC-funded breast screening programs; (3) the same classification in which only two categories, high nuclear grade and other, were used; (4) the Van Nuys system in which lesions are divided into high grade, non-high grade with necrosis and non-high grade without necrosis; and (5) a two-category classification based entirely on the presence or absence of comedo necrosis. Of the three systems with three categories, Van Nuys gave the highest overall kappa statistic of 0.42. Others gave similar values of 0.37 and 0.35 showing that assessing cell polarization in addition to nuclear grade neither improves nor worsens consistency. In all three systems, the middle category was associated with the lowest value for kappa. Of the two systems with two categories, that based on nuclear grade gave the highest overall kappa of 0.46 and that based on comedo necrosis the lowest of 0.34. The most robust histological features were thus high- and low-grade nuclei and necrosis as long as the latter did not involve the recognition of a comedo growth pattern. These values probably represent the maximum achievable, at least by reasonable numbers of pathologists in everyday practice. They are better than those previously reported for classification based entirely on architecture, but further improvement is needed.

Human papillomavirus genotype as a major determinant of the course of cervical cancer

PURPOSE

To determine whether the prognosis of invasive cancers of the uterine cervix is related to the type of human papillomavirus (HPV) associated with the tumor.

PATIENTS AND METHODS

Two hundred ninety-seven patients with invasive cervical cancer were prospectively registered from 1986 to 1994. HPV typing was performed on DNA extracted from frozen tumor specimens by means of Southern blot hybridization (SBH) and polymerase chain reaction (PCR) techniques. The median follow-up was 38 months.

RESULTS

HPV sequences were detected in 246 patients (83%): 150 patients had HPV16, 31 patients had HPV18, and 14 patients had one of the intermediate-oncogenic-risk HPV types (HPV31, 33, 35, 52, 58). In 51 patients, HPV type remained undetermined, and in 51 patients, no viral sequences were found. No significant associations were observed between virologic data and tumor stage or node status. The 5-year disease-free survival (DFS) rate was 100% for patients with intermediate-risk HPV-associated tumors, 58% for patients with HPV16-positive tumors, and 38% for patients with HPV18-positive tumors (P = .02). In multivariate analysis, patients with HPV18-associated tumors had a relative risk (RR) of death 2.4 times greater (95% confidence interval [CI], 1.29-4.59) than that for patients with HPV16, and 4.4 times greater (95% CI, 3.48-5.32) than that for patients with a tumor associated with a viral type different from HPV16/18.

CONCLUSION

The prognosis for invasive cancers of the uterine cervix is dependent on the oncogenic potential of the associated HPV type. HPV typing may provide a prognostic indicator for individual patients and is of potential use in defining specific therapies against HPV-harboring tumor cells.

Stereotactic fine-needle aspiration cytology of nonpalpable breast lesions: Institut Curie's experience of 243 histologically correlated cases

BACKGROUND

The early diagnosis of nonpalpable breast lesions is a medical challenge because of the low specificity of different radiologic modalities. Fine-needle aspiration cytology (FNAC) assisted by a stereotactic guidance is an adjunctive diagnostic approach in the management of these lesions. The primary purpose of this article was to assess the diagnostic accuracy of FNAC in patients with nonpalpable breast lesions.

METHODS

Three hundred and seventy-one lesions from 357 patients (all female) underwent FNAC using the stereotactically guided technique. Of these cases, 243 lesions from 238 patients subsequently were acquired by surgical excisional biopsies and formed the basis of this study. Statistical analyses of the cytologic and the histologic diagnoses of these cases were performed.

RESULTS

Histologically, 107 lesions (44%) were benign and 136 lesions (56%) were malignant. Of the 136 malignant lesions, cytology was concordant in 73 lesions (53.7%), suspicious in 15 lesions (11.0%), false-negative in 12 lesions (8.8%) (benign), and unsatisfactory in 36 lesions (26.5%). Among the 107 benign lesions, cytology was concordant with histology in 75 lesions (70.1%), whereas 4 lesions (3.7%) and 28 lesions (26.2%) were cytologically suspicious and unsatisfactory, respectively. No false-positive cytologies were found in the current series.

CONCLUSIONS

The current prospective study indicates that mammography combined with FNAC provides an accurate and practical diagnostic approach for the majority of nonpalpable lesions. Patients with unsatisfactory and false-negative lesions should undergo excisional biopsy.

Ultrasound-guided fine-needle aspiration cytology of nonpalpable breast lesions: Institut Curie's experience with 198 histologically correlated cases

BACKGROUND

The value of ultrasound-guided fine-needle aspiration cytology (FNAC) in the diagnosis of nonpalpable breast lesions remains a subject of debate. To determine the accuracy of this procedure in these lesions, a comparative analysis with open surgical biopsy in 188 patients was performed.

METHODS

Six hundred and fifty-four nonpalpable breast lesions detected by ultrasound in 585 patients were subjected to FNAC. Of these, 198 lesions (30.3%) from 188 patients were surgically excised.

RESULTS

Histologically, 105 lesions (53%) were malignant and 93 (47%) were benign. Among carcinomas, 65 cases (61.9%) were concordant, whereas 21 cases (20%) were suspicious, 12 cases (11.4%) were false-negative (benign), and 7 cases (6.7%) were unsatisfactory for diagnosis. Among benign lesions, 80 cases (86%) were concordant, whereas 5 cases (5.4%) were suspicious, and 8 cases (8.6%) were unsatisfactory. No false-positive diagnoses were made. The sensitivity of the FNAC method was 87.8%, the specificity was 94.5%, and the positive predictive value was 94.6%.

CONCLUSIONS

These results indicate that, with the exception of random microcalcified lesions, ultrasound-guided FNAC is a valuable and reliable technique in the diagnosis of nonpalpable breast lesions.

No significant predictive value of c-erbB-2 or p53 expression regarding sensitivity to primary chemotherapy or radiotherapy in breast cancer

To document whether c-erbB-2 over-expression or p53 accumulation in tumour cells was predictive of response to chemo- or radiotherapy, we analyzed a population of patients with breast cancer assigned to neo-adjuvant therapy (median follow-up: 54 months). T2/T3-N0N1b-M0 tumours (329 cases) were treated either by FAC chemotherapy or by radiotherapy before surgery, and the clinical response was classified as complete or incomplete. Expression of c-erbB-2 and p53 was retrospectively evaluated by immunohistochemistry. Proliferation rate was assessed by means of MIB-1 antibody and by S-phase fraction. A complete response to chemotherapy was observed in 38/167 patients (23%). Complete response rate was 20% in c-erbB-2-negative tumours, and rose to 31% in tumours with c-erbB-2 over-expression, but this trend was not statistically significant. There was no correlation between p53 staining and response to treatment, whereas chemosensitivity was found correlated with histological grade and S-phase. A complete response to radiotherapy was observed in 64 of the 156 evaluable patients (41%). Complete response rate was 41% in c-erbB-2- or p53-negative tumours, 54% in tumours with c-erb-B-2 over-expression, and 44% in tumours with p53 accumulation. There was no correlation between response to radiotherapy and histological grade or proliferative rate. No prognostic value was found for c-erbB-2 or p53 expression, whereas the 5-year survival rate was 85% for patients presenting a tumour with a low proliferating index (MIB-1 < 10%), and 68% for patients presenting a tumour with a high proliferative index. In multivariate analysis, node status (RR = 2), MIB-1 immunostaining (RR = 2), and tumour size (RR = 1.8) were found to be associated with survival. These results indicate that c-erbB-2 or p53 expression is not significantly associated with tumour response to neo-adjuvant chemo/radiotherapy in our series of breast cancers.

Increased expression of prolactin receptor gene assessed by quantitative polymerase chain reaction in human breast tumors versus normal breast tissues

The role of PRL in human breast tumorigenesis is not well understood. One of the limitations is the difficulty of accurately measuring PRL receptors (PRLR) in human tissues. We established a quantitative PCR method (Q-PCR) in T-47D human breast cancer cells and applied it to 29 patients, 25 of whom presented with either cancer or fibroadenoma. Four patients underwent a mammoplasty, and normal epithelial cells were cultured before Q-PCR. In T-47D cells, 31 x 10(6) messenger RNA molecules were detected per microgram of total RNA. In all patients, expression of the PRLR gene was detected, varying from 1500 to 1 x 10(6) molecules/microgram of RNA in normal tissues and from 4500 to 34.7 x 10(6) molecules/microgram of RNA in tumors. PRLR expression was always greater in tumor than in normal contiguous tissue and similar in cultured mammary epithelial cells and normal breast tissues. Estradiol and progesterone receptor-negative tumors expressed low levels of PRLR transcripts, similar to normal breast tissue from menopausal women. Immunocytochemical analysis of PRLR confirmed stronger staining in almost all tumor samples compared with normal tissues. A messenger RNA encoding locally produced human PRL was also identified by RT-PCR in every sample tested. Our results confirm PRLR gene expression in all tissues studied, and moreover, indicate that this expression is increased in human breast tumors vs. normal contiguous tissues.

Comparison of the prognostic value of Scarff-Bloom-Richardson and Nottingham histological grades in a series of 825 cases of breast cancer: major importance of the mitotic count as a component of both grading systems

The most commonly used system in Europe for breast carcinoma was developed by Scarff, Bloom and Richardson (SBR). It was recently modified by Elston and Ellis and significant improvement in reproducibility has been shown by using precise grading guidelines. This study investigated whether the use of this new grade (defined as the Nottingham grade, NG) would improve the prognostic stratification of patients. The respective prognostic value of the two grading schemes was compared in a retrospective series of 825 patients uniformly treated for a small invasive breast carcinoma and followed for a median of 6 years. Univariate and multivariate analysis showed that both histological grades were strongly correlated to overall and metastasis free survival. We have separately analysed the prognostic value of each of the three components used to assess the two grading systems and found that the mitotic index was the only significant prognostic factor for 5 year survival. Univariate analysis showed the count to be more discriminant in the NG scheme (p = 0.0006) than in the SBR scheme (p = 0.04). However, in univariate and multivariate analysis, the prognostic value of the global NG was not significantly better than SBR grade. This may be related, in part, to an uneven distribution of cases reflected by a much lower number of cases with a high mitotic index in the NG system (2%) than in the SBR system (10%). Our study emphasizes the importance of the mitotic count in assessing the prognosis of breast cancers and indicates that the factors which condition this count (tissue processing, microscopic observation, threshold) must be well standardized and controlled.

Sclerosing lymphocytic lobulitis in the male breast

Sclerosing lymphocytic lobulitis is an inflammatory disorder of the breast that is well recognised in women. It has only been reported previously in two men; two further men with the condition are described here. Both presented with a breast mass, and one was an insulin dependent diabetic. Biopsy specimens from both patients showed circumscribed perivascular and, to a lesser extent, periductal collections of B and T lymphocytes. Sclerosing lymphocytic lobulitis in the female breast shows predominantly perilobular inflammation. The predominantly perivascular distribution in men is consistent with the relative paucity of epithelium in the male breast. Interlobular fibrosis with epithelioid fibroblasts was also present.

Frequent association of human papillomavirus 16 and 18 DNA with anal squamous cell and basaloid carcinoma

Human papillomaviruses (HPVs) play a major role in the development of genital neoplasia. Their role in anal carcinogenesis is less clear, and the rate of HPV genome detected in invasive anal carcinoma varies considerably in the different reports. Moreover, the relationship of HPV to basaloid carcinoma, claimed to represent a histologic type different from the common squamous cell carcinoma, is still controversial. By use of both polymerase chain reaction and Southern blot hybridization on DNA extracted from frozen tissue specimens, we looked for HPV sequences in 12 cases of squamous cell carcinoma, in 9 cases of basaloid invasive carcinoma, in 1 case of carcinoma in situ, and in 1 case of Paget's disease of the anal canal. We have looked for correlations between virologic data and histologic types of tumors, and analyzed the clinical characteristics of HPV-positive and HPV-negative lesions. In our series, 20 (74%) of 27 cases of invasive anal carcinoma were positive for HPV DNA by Southern blot hybridization and/or polymerase chain reaction. HPV 16 DNA was found in 17 cases, HPV 18 in 2 cases, and in 1 case, the type of the HPV sequences detected remained undetermined (HPV X). Histovirologic correlations showed that 12 of 18 squamous cell carcinomas were associated with HPV 16 and that 8 of 9 cases of basaloid carcinoma were HPV positive; 5 case corresponded to HPV 16, 2 cases to HPV 18, and 1 case to HPV X. The carcinoma in situ case and the Paget's disease case were negative. An analysis of these data within the framework of the literature indicates that approximately 75% of cases of invasive anal carcinoma can actually be considered associated with HPV sequences. Basaloid carcinoma is also frequently associated with HPV genomes and is more likely to represent a histologic variant of squamous cell carcinoma than a separate entity. No clinical characteristics related to the HPV status of the tumors were observed in our series. Epidemiologic data on cervical, anal, and vulvar neoplasia are compared and their relation to the oncogenic properties of HPV in these different tissues are discussed.

[Intraductal cancer of the breast in women under age 35 years]

The incidence of intraductal carcinomas (IDC) of the breast is increasing. However, few cases have been reported in young women. Based on a series of 13,168 women treated for breast cancer at the Institut Curie over a 12-year period, this article analyses the prevalence, clinical presentation, prognosis and treatment of IDC in patients younger than 35 years. Of this series of 13,168 cancers, 882 occurred in women under the age of 35 years (6.7%). Sixteen of these cases (2%) were strictly intraductal lesions and therefore constituted the study population. The frequency of IDC in women under the age of 35 years was identical to that of IDC in the general population of this study. The circumstances of discovery were: palpable tumour in seven cases (44%), mammographic discovery in four cases (25%), nipple discharge in five cases (31%). Histological examination revealed a well-differentiated IDC in two cases, moderately differentiated in seven cases and poorly differentiated in five cases (two cases not specified). Conservative treatment by lumpectomy and irradiation was performed in nine patients, and another seven patients were treated by mastectomy and low axillary lymph node dissection. The mean follow-up was 83 months (range: 5 to 156 months). A single patient has relapsed: an isolated invasive mammary recurrence, 6 years after conservative treatment. This patient in now in complete remission after mastectomy. All patients are therefore alive, with no evidence of disease, at 83 months. In the group of women younger than 35, the frequency of IDC appeared to be identical to that observed in the general population. Their prognosis after treatment is excellent, and identical to that of IDC in older women. Conservative treatment is justified in localized forms, but mastectomy with immediate reconstruction must be performed in the presence of extensive disease.

Clustered breast microcalcifications: evaluation by dynamic contrast-enhanced subtraction MRI

OBJECTIVE

Our goal was to evaluate dynamic contrast-enhanced subtraction MRI in the diagnosis of isolated clustered calcifications of the breast.

MATERIALS AND METHODS

One hundred seventy-two patients underwent surgical biopsy for isolated clustered breast calcifications. Their mammograms showed round (n = 88) or linear/irregular (n = 84) microcalcifications. All patients had a preoperative Gd-DOTA-enhanced subtraction dynamic study. Any early contrast enhancement in the breast parenchyma concomitant with early enhancement of normal vessels was considered positive.

RESULTS

Fifty-eight in situ carcinomas, 22 invasive carcinomas, and 92 benign lesions were found at histological analysis. Dynamic MR sequences showed early contrast enhancement in 76 of 80 malignant lesions (sensitivity 95%) and in 45 of 92 benign lesions (specificity 51%). Two invasive and two intraductal carcinomas did not show early contrast enhancement. Three independent observers agreed in rating early contrast enhancement in 143 of 172 lesions.

CONCLUSION

Poor specificity limits the diagnostic accuracy of dynamic contrast-enhanced subtraction MRI in distinguishing benign from malignant microcalcifications on mammography.

Ductal carcinoma in situ: MR imaging-histopathologic correlation

PURPOSE

To correlate histopathologic and magnetic resonance (MR) imaging findings of ductal carcinoma in situ (DCIS).

MATERIALS AND METHODS

Thirty-six women with DCIS underwent preoperative contrast material-enhanced subtraction dynamic MR imaging. Concomitant early contrast enhancement in the breast parenchyma with normal vessels was considered a positive finding. The size and shape of early enhancement were correlated with the size and density packing of ducts involved by DCIS. Tumor angiogenesis in the stroma that surrounded the ducts was evaluated with immunoperoxidase staining.

RESULTS

Early contrast enhancement was demonstrated in 34 patients with DCIS but not in two patients with comedo-type DCIS. Tumor angiogenesis was demonstrated in the stroma. The size and morphology of contrast-enhanced lesions significantly correlated with the size (P = .0085) and density packing of ducts involved by DCIS (P = .012).

CONCLUSION

Contrast enhancement on dynamic MR images of DCIS may be due to the presence of tumor angiogenesis in the stroma.

Ductal carcinoma in situ: a proposal for a new classification

Details of a proposed new classification for ductal carcinoma in situ (DCIS) are presented. This is based, primarily, on cytonuclear differentiation and, secondarily, on architectural differentiation (cellular polarisation). Three categories are defined. First is poorly differentiated DCIS composed of cells with very pleomorphic, irregularly spaced nuclei, with coarse, clumped chromatin, prominent nucleoli, and frequent mitoses. Architectural differentiation is absent or minimal. The growth pattern is solid or pseudo-cribriform and -micropapillary (without cellular polarisation). Necrosis is usually present. Calcification, when present, is amorphous. Second, at the other end of the spectrum is well-differentiated DCIS, composed of cells with monomorphic, regularly spaced nuclei containing fine chromatin, inconspicuous nucleoli, and few mitoses. The cells show pronounced polarisation with orientation of their apical border towards intercellular spaces usually resulting in cribriform, micropapillary and clinging patterns, although a solid pattern of well-differentiated DCIS also occurs. Necrosis is uncommon. Calcifications, when present, are usually psammomatous. The third category, intermediately differentiated DCIS, is composed of cells showing some pleomorphism but not so marked as in the poorly differentiated group. There is, however, always evidence of polarization around intercellular spaces, although this is not so pronounced as in the well-differentiated group. These two criteria, cytonuclear differentiation and architectural differentiation, have been found to be more consistent throughout a DCIS lesion than previously employed criteria of architectural pattern or the presence or absence of necrosis.

Mammographically-detected ductal in situ carcinoma of the breast analyzed with a new classification. A study of 127 cases: correlation with estrogen and progesterone receptors, p53 and c-erbB-2 proteins, and proliferative activity

The new histologic classification proposed by Holland et al was applied to 127 cases of mammographically-detected ductal carcinoma in situ (DCIS). The relationship between histologic types and tumor cell expression of estrogen and progesterone receptors, p53 protein, c-erbB-2 oncoprotein, and proliferative activity markers was evaluated. There were 38 (30%) well differentiated, 39 (31%) intermediately differentiated and 50 (39%) poorly differentiated DCIS. Immunohistochemistry showed that 81% of the tumors were estrogen-receptor positive and 73% progesterone receptor positive. p53 protein and c-erbB-2 oncoprotein expression was identified in 40% and 57% of the cases, respectively. Growth-fraction determination with the Ki-67 antibody showed that 52% of the tumors had high proliferative activity. A highly significant association was found between the histologic types of DCIS and p53 protein, c-erB-b2 oncoprotein, and proliferative activity marker expression: these biological markers were more frequently overexpressed in less differentiated DCIS. No significant relationship with estrogen or progesterone receptor expression was noted. A strong relationship with the amount of tumor necrosis was also found. The clinical significance of these results should, however, be determined by long-term follow-up studies of patients with DCIS.

Cytogenetic study of 30 colorectal adenomas

The cytogenetic analysis of 30 colorectal adenomas obtained from 24 patients is reported. Only normal karyotypes were observed in eight cases. Among the 22 adenomas with abnormal karyotypes, 15 showed clonal anomalies. Chromosome gains involving chromosomes 13, 20, 7, 9, and 12 were recurrently observed. Chromosome 18 was frequently lost or involved in translocations at bands q21-q22. More chromosome alterations were observed in the cases in which histologic examination revealed severe dysplasia or a carcinomatous component. These anomalies are discussed in relation to those described in colorectal adenocarcinoma.

Cytogenetic study of breast cancer: clinicopathologic significance of homogeneously staining regions in 84 patients

A cytogenetic study performed on 84 primary breast cancers was conducted to detect the presence of chromosomes with homogeneously staining regions (HSRs) which are assumed to correspond to gene amplification. Homogeneously staining regions were found in 60% of the cases. To assess the prognostic significance of HSRs, clinical and pathologic data were correlated with the cytogenetic findings. Median follow-up for the 84 patients was 40 months. Differences in overall survival and disease-free survival rates between patients with HSRs (50 cases) and patients without HSRs (34 cases) were not significant. Although an excess of HSRs was found in patients considered to have poor prognostic factors (eg, young age, high histologic grade, metastatic axillary nodes, loss of hormonal receptors), no statistically significant correlation between variables could be demonstrated. The high percentage of cases with HSRs strongly suggests that they have an important biologic role, but more cases should be studied with a longer follow-up to assess their significance.

Induction chemotherapy in advanced head and neck tumors: results of two randomized trials

From March 1983 to December 1989, 208 patients with locally advanced squamous cell carcinoma of the head and neck were successively included into two randomized induction chemotherapy trials. The chemotherapy regimen of the first trial, which included 100 patients, consisted of two cycles of a combination of cisplatin, bleomycin, vindesine and mitomycin C; while that of the second trial, which included 108 patients, consisted of three cycles of a combination cisplatin, 5-fluorouracil by continuous infusion and vindesine. Local treatment was the same in the two trials: primary radiotherapy in all patients. The response was then evaluated; in the case of a poor response at 55 Grays surgery was performed; otherwise, radiotherapy was continued to full doses (possibly followed by salvage surgery). The tumor and lymph node responses to chemotherapy (complete and partial response) were higher in the second trial than in the first: 70% versus 50% for primary lesions, 47% versus 25% for lymph nodes. The toxicity of the two chemotherapy regimens was minimal. In the two trials, an initial major response to chemotherapy predicted subsequent efficacy of irradiation in 80% of the patients. The significance of the complete response at the end of the irradiation varies with the previous response to the chemotherapy. With a median follow-up of 60 months with the first chemotherapy regimen and 30 months with the second, overall survival and disease-free interval were very similar in the two groups. The incidence of distant metastasis was significantly reduced (p less than 0.03) with chemotherapy. This trial suggests the need to test new chemotherapy protocols according to new schemes of treatment, with chemotherapy given concurrently with or following the completion of standard treatment by means of multicenter randomized trials.

Breast cancer genetic evolution: I. Data from cytogenetics and DNA content

A general scheme of chromosome alterations occurring during tumor progression is proposed from the cytogenetic study of 113 breast carcinomas. For 76 of these tumors, chromosome numbers and rate of chromosome rearrangements were correlated with DNA content studied by flow cytometry. A series of 536 cases was used as control for flow cytometry. The following evolution can be proposed: 1. occurrence of unbalanced rearrangements decreasing chromosome number and DNA content; 2. correlatively to the rate of chromosome rearrangements, formation of endoreduplications leading to hyperploid sidelines; 3. persistence of the near diploid cells and decrease of chromosome number to about 35 and of DNA index to .85; 4. more frequently, elimination of the near diploid cells and complete passage to hyperploidy; 5. further losses of chromosomes in the hyperploid tumors, whose karyotypes can decrease to about 55 chromosomes and a DNA index of 1.35; 6. eventually, occurrence of a second endoreduplication, leading to an apparent near tetraploidy. The rate of rearranged chromosomes may reach 80% in both near diploid tumors with 35-40 and hyperploid tumors with 55-65 chromosomes which can be regarded as those with the highest degree of tumor progression. It is shown that the increase of chromosome number and DNA index above diploidy is very limited, and that all tumors with more than 50 chromosomes and 1.35 DNA content passed through endoreduplication. This results in many possible losses of heterozygosity in these cases.

Prolonged G2 phase of breast cancer cells and chromosome damage

5-bromodeoxyuridine incorporation was studied in metaphase chromosomes from 24 breast tumour specimens, including 23 adenocarcinomas. In these 23 cases, a slow cell cycle was observed, with a long (8 h) G2 phase. This slowing of the cell cycle, which was poorly related to the degree of polyploidy, was significantly related to the number of chromosome anomalies: the cell cycle was particularly slow when many rearranged chromosome were observed. These in vitro findings during the first cell cycle cannot easily be transposed to the in vivo situation. By analogy with Fanconi anaemia, in which both chromosome lesions and a long G2 phase are detected, a DNA repair defect and/or high DNA mutagenesis might exist in breast cancer cells.

GST pi gene is frequently coamplified with INT2 and HSTF1 proto-oncogenes in human breast cancers

The glutathione S-transferase gene (GST pi) is located on the same chromosome band (11q13) as proto-oncogenes INT2 and HSTF1 which are frequently amplified in breast cancer. Using the Southern blot technique, we looked for the amplification of the GST pi gene in 17 fresh tumors from human mammary carcinoma. The tumors were preselected because either they had an amplification of the INT2 proto-oncogene detected by dot blot, or their karyotypes exhibited or did not exhibit homogeneously staining regions, a cytogenetic character indicating amplification. Coamplification of GST pi, HSTF1 and INT2 was observed in five tumors, and coamplification of GST pi and HSTF1 without amplification of INT2 in another tumor. We also observed coamplification of GST pi, INT2, HSTF1 in the mammary carcinoma cell line MDA/MB134, whereas GST pi alone was amplified in the mammary epithelial cell line HBL100. These results indicate that INT2, HSTF1 and GST pi belong to the same large amplicon. Since GST pi is involved in intracellular detoxication and since chemotherapeutic drugs are among its substrates, it will be of interest to study GST pi gene expression as well as the response to chemotherapy in patients presenting this amplicon.