The pathology of familial breast cancer: The pre-BRCA1/BRCA2 era - historical perspectives
© Current Science Ltd 1999
Received: 24 September 1999
Accepted: 27 October 1999
Published: 1 December 1999
A proportion of breast carcinomas develop as a result of a genetic predispostion to the disease. Prior to cloning of the BRCA1 and BRCA2 genes a limited number of studies were carried out to identify specific histopathological characteristics of hereditary breast cancer. These studies are the subject of this review. The main finding was the association of the (atypical) medullary type of breast cancer with a family history; the most important caveat being that medullary breast cancer is found more frequently in young patients. In view of the frequent bilateral occurrence of lobular cancer, this histologic type is also likely to be associated with a predisposing genetic defect. Future investigations will have to test this hypothesis. In addition to mutations in the BRCA1 and BRCA2 genes, there are as yet unidentified genetic defects predisposing to breast cancer development, and histopathology may well help in identifying these genes in the future.
Keywordsassociation breast carcinoma familial, histopathology
Anecdotal evidence from individual families in which breast cancer occurs very frequently and large epidemiological studies have shown that some women have a familial predisposition to breast cancer. The anecdotal evidence includes the pedigree of Broca's family . He was a famous French surgeon (1824-1880), and in his family tree (which comprised over five generations) 10 out of 24 women died of breast cancer. Systematic epidemiological studies performed in the second half of the 20th century have shown that, in women with a family history of breast cancer, the risk of breast cancer is increased two-to threefold ('familial breast cancer'). Such studies have also shown that there are families in which breast cancer risk is inherited in an autosomal-dominant fashion ('hereditary breast cancer'). In recent years, it has been shown that germline mutations in the BRCA1 and BRCA2 genes account for a large proportion of cases of hereditary breast cancer.
Histopathological findings and careful autopsy examination have played a major role in the recognition of many familial cancer syndromes , including multiple endocrine neoplasia type II and Beckwith-Wiedemann syndrome. The creation of tissue archives that include a coded index of patient details, tissue and diagnosis at a time when the possibilities for its use were remote has placed pathologists in a unique position to play a central role in familial breast cancer research. The knowledge of the histopathological features will also help in understanding the genetic defects that underlie the various forms of familial predisposition. Histopathological diagnosis and tissue archives may therefore be of fundamental importance in our understanding of familial breast cancer, and hospitals would be wise to look after this unique resource.
This review describes histopathological studies with regard to specific histological features of breast carcinoma in patients who have developed this disease as part of what was described as 'familial breast cancer' or 'hereditary breast cancer' before the identification of the BRCA1 and BRCA2 genes. The histological features of breast carcinomas arising in patients with germline mutations in the BRCA1 or BRCA2 genes are discussed in this issue by Lakhani.
In addition to mutations in the BRCA1 and BRCA2 genes, there are as yet unidentified genetic defects that predispose to breast cancer development, and histopathology may well help in identifying these genes in the future.
Histopathology of breast cancer in patients with a family history of breast cancer
Histological classification of invasive breast cancer, including the estimated proportion of all breast carcinomas for each histologic type
Estimated frequency (%)
Ductal carcinoma, not otherwise specified
Atypical medullary carcinoma
Other (metaplastic, papillary, adenoid cystic, etc)
Breast cancer is a common disease, occurring in approximately one in 12 European or North American women. In part, clustering of breast cancer in a family is a result of chance, because breast cancer is so frequent; in some families, the clustering is the result of shared environmental risk factors; and in a proportion of families an underlying genetic defect will be the culprit. Before the identification of the BRCA1 and BRCA2 genes, it was impossible to discriminate between these possibilities. This still applies to all other as yet unidentified genetic defects that predispose to breast cancer.
Selected studies of the relationship between histopathology of breast carcinoma and family history
Rosen et al [4**]
Breast cancer histology associated with family history (consecutive series of patients treated at Memorial Hospital, New York)
Medullary cancer is associated with maternal breast cancer; lobular cancer is associated with breast cancer in a sister
Claus et al [5**]
Breast cancer histology associated with epidemiological factors: part of the Cancer and Steroid Hormone study
Medullary cancer is associated with young age; lobular carcinoma in situ is associated with family history
In addition to family history, a number of other patient characteristics have been found to be associated with his-tological type. For example, patients with medullary breast cancer have been reported to be younger than those with other histological types, and medullary carcinomas have been reported to be more frequent in blacks than in whites [5**]. A comprehensive review of the histopathology of familial breast cancer and of breast cancer in young women was presented by Marcus et al [6*].
Historically, familial breast cancer has been found to be associated with medullary carcinoma, tubular carcinoma and lobular carcinoma. These are considered briefly below.
In patients who had a mother with breast cancer, Rosen et al [4**] found medullary cancer in 16% and atypical medullary cancer in 18% of women. Of note is that these authors did not find an increased frequency of medullary cancer in patients who had a sister with breast cancer, an observation that was also made by Anderson in 1994 [6*]. Claus et al [5**] found an increased frequency of medullary cancer in young women, but no association with family history. An important caveat with respect to the diagnosis of medullary carcinoma is that there is considerable inter-observer variability in making this diagnosis. It is clear, however, that tumours with features that are consistent with medullary carcinoma are more frequent in patients with a family history and in younger patients. Probably the most important property of these tumours is a high proliferative activity, resulting in a tumour with pushing margins and high mitotic count.
Lagios et al  identified 17 tubular cancers in mastectomy specimens from a cohort of 211 breast cancer patients. A family history that was positive for mammary carcinoma in a first-order relative was recorded for six out of 15 patients analyzed (40% versus 16% in the patients with other histological types of breast cancer).
Lobular carcinoma in situ and invasive lobular carcinoma
Among the histopathological types of breast cancer, lobular cancer stands out as a candidate for a tumour caused by a genetically inherited predisposition. The main reason for this is the high frequency of bilateral invasive and in situ lobular breast cancer. Claus et al [5**] found that patients with lobular carcinoma in situ were more likely than patients with other histopathological types of breast cancer to have a mother and/or sister who had breast cancer. In their series, lobular carcinoma in situ was bilateral in 27% of cases [5**]. Rosen et al [4**] found that 17% of patients who had one or more sisters with breast cancer were of lobular histologic type.
It is likely that lobular cancer develops as part of an inherited predisposition, and that this is due to low penetrance gene(s). Mutations in the E-cadherin gene can be identified in the majority of lobular carcinomas. These mutations are all somatic mutations, however, and germline mutations have not been identified in patients with lobular cancer [8,9].
Can preneoplastic histopathological breast alterations be identified in familial breast cancer?
A number of histologic alterations of the breast have been identified, which are associated with an increased risk of developing breast cancer. These histologic alterations include epithelial hyperplasia, atypical ductal hyperplasia , fibroadenoma with 'complex features' , scar lesions  and cysts . These conditions are all associated with an increased risk of developing breast cancer in both breasts (and not only in the breast from which the tissue showing these histological alterations has been excised). To date, there is no evidence that they are direct precursors of breast carcinoma, and they should be viewed as markers of increased risk. The mechanism that underlies the association of these lesions with increased risk of breast cancer development is currently unknown. If epithelial hyperplasia, atypical ductal hyperplasia, fibroadenoma with 'complex features' or scar lesions are present, the risk of developing breast cancer is roughly doubled if there is also a family history of breast cancer. Fine needle aspiration from all four quadrants of both breasts has been performed in women without breast abnormalities , and it was noted that an increased frequency of 'atypical ductal hyperplasia' was found in women with a family history of breast cancer compared with women without a family history. As has also been pointed out in other reviews in this issue, atypical ductal hyperplasia is a histological diagnosis that cannot been made on the basis of cytological examination. Therefore, these findings cannot be taken as evidence that preneoplastic conditions can be diagnosed in women with a familial predisposition to develop breast cancer.
Ductal and lobular carcinoma in situ are the only known direct precursor lesions to breast cancer, and ductal carcinoma in situ has not been reported in association with breast cancer family history. In a series of 605 bilateral prophylactic mastectomies performed because of a family history of breast cancer , not one case of carcinoma in situ was found.
It must be realized that it is difficult to find microscopic precursor lesions to invasive breast cancer if these lesions cannot be detected using mammography or magnetic resonance imaging. The pathological examination of a prophylactic mastectomy specimen will include taking several sections from macrosopically normal parts of the breast, usually resulting in examination of less than 1% of all breast tissue. Because it is to be expected that cancer will start in one (microscopic) area of the breast (which is also the case when there is a germline gene mutation predisposing to breast cancer), the risk of finding such a minute lesion is small. Germline mutations in BRCA1, BRCA2 and other genes could theoretically also lead to multiple or even diffuse histological alterations (for instance multiple foci of proliferation of dysplastic epithelium, analogous to multiple polyps in familial adenomatosis coli). Such diffuse alterations in the breast have not been identified to date, however, and it is very unlikely that they are present.
Breast cancer histopathology in other cancer syndromes
Cancer syndromes that are also associated with an increased risk of developing breast cancer include Cowden's disease, the Li-Fraumeni cancer syndrome and ataxia-telangiectasia. No studies of the histopathological features of breast carcinomas that occur in patients with these syndromes have been published.
Before the cloning of the BRCA1 and BRCA2 genes, a number of studies reported an association of histopathological type with a family history, but these studies have been difficult to interpret due to the small number of samples and differing criteria for 'positive family history' and pathological typing. Hence, there are only limited data on specific histologic patterns in breast carcinomas that are associated with hereditary and familial breast cancer. The main finding was the association of the medullary type of breast cancer with a family history; the most important caveat being that medullary breast cancer is found more frequently in young patients. As is seen elsewhere in this review series, the association of family history with medullary breast cancer is now confirmed by studies based on knowledge of BRCA1 and BRCA2 mutation status.
In view of the frequent bilateral occurrence of lobular cancer, this histological type is also likely to be associated with a predisposing genetic defect. Future investigations will have to test this hypothesis.
- Broca P: . Traité des Tumeurs. Paris: Asselin. 1866Google Scholar
- Jass JR: Familial cancer: histopathological perspectives. J Clin Pathol. 1997, 50: 892-895.View ArticlePubMedPubMed CentralGoogle Scholar
- Mulcahy GM, Platt R: Pathological aspects of familial carcinoma of the breast. In: Genetics and Breast Cancer. 1981, : 65-97.Google Scholar
- Rosen PP, Lesser ML, Senie RT, Kinne DW: Relationship of family history to tumor type. Cancer. 1982, 50: 171-179. One thousand and twenty-four women treated consecutively for breast carcinoma at Memorial Hospital, New York were studied for the association between hispathological features and family history of breast cancer.View ArticlePubMedGoogle Scholar
- Claus EB, Risch N, Thompson WD, Carter D: Relationship between breast histopathology and family history of breast cancer. Cancer. 1993, 71: 147-153. Study of the relationship between breast cancer histology and a number of epidemiologic risk factors associated with breast cancer in 4071 patients with breast cancer from the Cancer and Steroid Hormone study.View ArticlePubMedGoogle Scholar
- Marcus JN, Watson P, Page DL, Lynch HT: Pathology and heredity of breast cancer in younger women. J Natl Cancer Inst . 1994, 16: 23-34. This is a review article on the association of histopathologic tumour type and family history/young age.Google Scholar
- Lagius MD, Rose MR, Margolin FR: Tubular carcinoma of the breast: association with multicentricity, bilaterality, and family history of mammary carcinoma. Am J Clin Pathol. 1980, 73: 25-30.View ArticleGoogle Scholar
- Anderson DE: Genetic study of breast cancer: identification of a high risk group. Cancer. 1999, 34: 1090-1097.View ArticleGoogle Scholar
- Berx G, Cleton-Jansen AM, Nollet F, et al: E-cadherin is a tumour/ invasion suppressor gene mutated in human lobular breast cancers. EMBO J. 1995, 14: 6107-6115.PubMedPubMed CentralGoogle Scholar
- Berx G, Cleton-Jansen A, Strumane K, et al: E-cadherin is inactivated in a majority of invasive human lobular breast cancers by truncation mutations throughout its extracellular domain. Oncogene. 1996, 13: 1919-1925.PubMedGoogle Scholar
- Dupont WD, Page DL: Risk factors for breast cancer in women with proliferative breast disease. N Engl J Med. 1985, 312: 146-151.View ArticlePubMedGoogle Scholar
- Dupont WD, Page DL, Parl FF, et al: Long-term risk of breast cancer in women with fibroadenoma. N Engl J Med. 1994, 331: 10-15. 10.1056/NEJM199407073310103.View ArticlePubMedGoogle Scholar
- Jacobs TW, Byrne C, Colditz G, Connolly JL, Schnitt SJ: Radial scars in benign breast-biopsy specimens and the risk of breast cancer. N Engl J Med. 1999, 340: 430-436. 10.1056/NEJM199902113400604.View ArticlePubMedGoogle Scholar
- Dixon MF, McDonald C, Elton RA, Miller WR: Risk of breast cancer in women with palpable breast cysts: a prospective study. Lancet. 1999, 353: 1742-1745. 10.1016/S0140-6736(98)06408-3.View ArticlePubMedGoogle Scholar
- Skolnick MH, Cannon-Albright LA, Goldgar DE, et al: Inheritance of proliferative breast disease in breast cancer kindreds. Science. 1990, 250: 1715-1720.View ArticlePubMedGoogle Scholar
- Hartmann LC, Schaid DJ, Woods JE, et al: Efficacy of bilateral prophylactic mastectomy in women with a family history of breast cancer. N Engl J Med. 1999, 340: 77-84. 10.1056/NEJM199901143400201.View ArticlePubMedGoogle Scholar