Tubular carcinoma: a variant of secretory breast carcinoma

Adenomyoepithelioma of the Breast. A Case Report

Adenomyoepithelioma is a proliferative disorder of both epithelial and myoepithelial cells. This lesion may be found in salivary glands, skin appendages and, very rarely, in the mammary gland. Adenomyoepithelioma was first described in 1970 and very few cases have so far been reviewed in the literature. This paper reports the clinical, histological and immunohistochemical characteristics of an adenomyoepithelioma in a 24 year old woman; to our knowledge this is the first published case in such a young patient. The clinical feature suggested a fibroadenoma. A more complete study of the excised tumor tissue by immunohistochemical and ultrastructural analysis proved that the correct diagnosis was adenomyoepithelioma. Whether adenomyoepithelioma is a benign or a low-grade malignant lesion is still controversial and, therefore, the therapeutic approach is not well defined.

Secretory carcinoma of the breast and its histopathological mimics: value of markers for differential diagnosis

AIMS

Secretory carcinoma (SC) is a rare histological type of breast cancer, and ETV6-NTRK3 gene fusion is highly specific to it. The differential diagnoses of SC include acinic cell carcinoma (ACCA) and cystic hypersecretory carcinoma (CHC), as well as invasive ductal carcinoma (IDC). For patients with these rare but distinctive histological subtypes, SC and its histopathological mimics should be differentiated from each other. However, differential markers have not yet been assessed systematically, and we aimed to identify and evaluate novel and existing markers.

METHODS AND RESULTS

We reviewed 19 cases diagnosed initially as SC using integrated diagnostic techniques, including morphology, immunohistochemistry and molecular pathology, and validated promising markers in 445 breast cancers. We reclassified 19 formerly diagnosed 'SCs' into nine SCs, three ACCAs, three CHCs, three IDCs and one microglandular adenosis. We confirmed that ETV6-NTRK3 gene rearrangement and amylase positivity are good diagnostic markers for SC and ACCA, respectively. Vacuolar staining for adipophilin, positivity for α-lactalbumin and negativity for ETV6 rearrangement are diagnostic markers for CHC.

CONCLUSIONS

In this study, we propose a panel of four markers (ETV6 rearrangement, amylase, α-lactalbumin and adipophilin) for distinguishing SC, ACCA, CHC and IDC. This simple but robust panel will serve pathologists well as a practical guide for reaching an appropriate diagnosis.

Epitheliosis, infiltrating epitheliosis, and radial scar

The lesion termed "infiltrating epitheliosis" (IE) by Azzopardi is described using his original criteria. The differential diagnosis from radial scar (RS) is discussed. It appears that IE and RS are histologically and histogenetically different and are also associated with a different risk of carcinoma. IE can be associated with either in situ or invasive carcinoma, whereas RS being more like a process of involution is very seldom involved by a carcinoma. Therefore, whatever name is used among the several found in the literature, it should be made clear they are not interchangeable when reporting on lesions like IE and RS.

Established breast cancer risk factors by clinically important tumour characteristics

Breast cancer is a morphologically and clinically heterogeneous disease; however, it is less clear how risk factors relate to tumour features. We evaluated risk factors by tumour characteristics (histopathologic type, grade, size, and nodal status) in a population-based case-control of 2386 breast cancers and 2502 controls in Poland. Use of a novel extension of the polytomous logistic regression permitted simultaneous modelling of multiple tumour characteristics. Late age at first full-term birth was associated with increased risk of large (> 2 cm) tumours (odds ratios (95% confidence intervals) 1.19 (1.07-1.33) for a 5-year increase in age), but not smaller tumours (P for heterogeneity adjusting for other tumour features (Phet) = 0.007). On the other hand, multiparity was associated with reduced risk for small tumours (0.76 (0.68-0.86) per additional birth; Phet = 0.004). Consideration of all tumour characteristics simultaneously revealed that current or recent use of combined hormone replacement therapy was associated with risk of small (2.29 (1.66-3.15)) and grade 1 (3.36 (2.22-5.08)) tumours (Phet = 0.05 for size and 0.0008 for grade 1 vs 3), rather than specific histopathologic types (Phet = 0.63 for ductal vs lobular). Finally, elevated body mass index was associated with larger tumour size among both pre- and postmenopausal women (Phet = 0.05 and 0.0001, respectively). None of these relationships were explained by hormone receptor status of the tumours. In conclusion, these data support distinctive risk factor relationships by tumour characteristics of prognostic relevance. These findings might be useful in developing targeted prevention efforts.

Immunostaining of Type IV Collagen and Smooth Muscle Actin as an Aid in the Diagnosis of Breast Lesions

The immunohistochemical staining patterns of type IV collagen (TIVC) and smooth muscle actin (SMA) were studied in benign and malignant breast lesions in order to assess their usefulness in the differential diagnosis of difficult lesions. Eighty-six in situ breast carcinomas (8 with microinvasion; 1 diagnosed after immunostaining) and 58 invasive carcinomas, with associated benign lesions including 87 nonproliferative fibrocystic changes, 19 sclerosing adenosis, 17 atypical hyperplasias, 7 benign papillary proliferations, 6 radial scars, and 105 normal mammary tissue, were studied. TIVC and SMA were concomitantly positive throughout in 94% of benign tissues, in 16% of in situ carcinomas, but in none of the invasive carcinomas. Conversely, both markers were negative in 66% of invasive carcinomas, but in none of the benign breast tissue and none of the in situ carcinomas. In 6% of the benign tissues, in 21% of in situ carcinomas, and in 34% of invasive carcinomas only one of the markers was positive. In the remaining 63% of the in situ carcinomas there were discontinuities of the staining of both markers. It is therefore suggested that a diagnosis of invasive malignancy can be confirmed when both markers are negative, and ruled out when both markers are positive. This is particularly useful, in our experience, in the identification of small foci of invasion. The stains are useful when used in parallel, whereas they may be misleading when used singly. The staining pattern is not useful in the differential diagnosis of atypical hyperplasia and in situ carcinoma.

Probability of axillary node involvement in patients with tubular carcinoma of the breast

BACKGROUND

The aim of this study was to investigate the frequency of axillary metastasis in women with tubular carcinoma (TC) of the breast.

METHODS

Women who underwent axillary dissection for TC in the Western Sydney area (1984--1995) were identified retrospectively through a search of computerized records. A centralized pathology review was performed and tumours were classified as pure tubular (22) or mixed tubular (nine), on the basis of the invasive component containing 90 per cent or more, or 75--90 per cent tubule formation respectively. A Medline search of the literature was undertaken to compile a collective series (20 studies with a total of 680 patients) to address the frequency of nodal involvement in TC. A quantitative meta-analysis was used to combine the results of these studies.

RESULTS

The overall frequency of nodal metastasis was five of 31 (16 per cent); one of 22 pure tubular and four of nine mixed tumours (P = 0.019). None of the tumours with a diameter of 10 mm or less (n = 16) had nodal metastasis compared with five of 15 larger tumours (P = 0.018). The meta-analysis of 680 women showed an overall frequency of nodal metastasis in TC of 13.8 (95 per cent confidence interval 9.3-18.3) per cent. The frequency of nodal involvement was 6.6 (1.7--11.4) per cent in pure TC (n = 244) and 25.0 (12.5--37.6) per cent in mixed TC (n = 149).

CONCLUSION

A case may be made for observing the clinically negative axilla in women with a small TC (10 mm or less in diameter).

The delimitation of tubular carcinoma of the breast

Five hundred consecutive breast carcinomas from the first screening round of the Breast Cancer Detection Demonstration Project were studied quantitatively and semiquantitatively for features relevant to the diagnosis of tubular carcinoma. Tubularity was defined as the proportion of tumor cells that were adjacent to an open lumen. Nuclear morphology and mitotic activity were graded 1 to 3, and the presence of apocrine snouts as absent, few, common, or prominent. In plots and statistical cluster analysis, tubular carcinoma appears as part of a continuous spectrum of morphologies and not as a distinct entity. In multivariate analysis, apocrine snouts had no significant association with either nodal status or deaths of breast cancer. Tumors with 70% or greater tubularity by our definition and mitosis and nuclear grades 1 were not associated with either nodal metastases or deaths of breast cancer. The question is raised whether tubular carcinoma at the benign end of a spectrum shades into benign glandular proliferations, with particular reference to microglandular adenosis. A uniform and precise definition of tubularity is needed for the attainment of sufficient collective experience to delimit tubular carcinoma both from more aggressive carcinomas and from benign proliferations.

Immunoreactivity of ductal cells with putative myoepithelial markers: A potential pitfall in breast carcinoma

The identification of an intact layer of myoepithelial cells (MECs) located between epithelial cells and the basal lamina is useful in differentiating benign breast lesions and carcinoma in situ from invasive breast carcinoma. In the present study we used three antibodies considered to be putative markers of MECs (S100 protein, muscle-specific actin [HHF-35], and smooth muscle actin [SMA]) in 100 formalin-fixed, paraffin-embedded histologic sections of breast in an attempt to compare their value in demonstrating MECs in benign breast tissue and breast carcinomas. We concluded that for identifying MECs in benign breast tissue, SMA appears to be the most reliable, followed closely by HHF-35, but S100 is very unreliable for this purpose. In breast carcinoma, all three stains showed variable cross-reactivity with myofibroblasts, being greatest with SMA. A significant number of tumor cells in ductal carcinoma, both intraductal and invasive, stain with these markers and this "cross-reactivity" is extremely high with HHF-35. Thus, immunohistochemistry should be interpreted cautiously in differentiating benign, in situ, and invasive breast neoplasms. The "cross-reactivity" also suggests the possibility of myoepithelial differentiation and/or high actin content of breast tumor cells.

Hereditary breast cancer: pathobiology, prognosis, and BRCA1 and BRCA2 gene linkage

BACKGROUND

The purpose of this investigation was to determine if there are pathobiologic differences between BRCA1-related and BRCA2-related hereditary breast cancer (HBC) and non-HBC.

METHODS

On the basis of linkage to chromosomes 17q or 13q and/or the presence of ovarian and male breast cancer, HBC families were classified as either "BRCA1-related" (26 families, 90 breast cancer pathology cases) or "Other" (26 families, 85 cases), in which most BRCA2 cases were likely to reside. Cases were compared with 187 predominantly non-HBC cases. Tumors were assessed for histologic type, grade, and ploidy and S-phase fraction by quantitative DNA flow cytometry. Clinical presentation and available follow-up data were obtained.

RESULTS

BRCA1-related and Other HBC patients each presented at lower stage (P = 0.003) and earlier age than non-HBC patients (mean, 42.8 years and 47.1 years vs. 62.9 years, P = 0.0001). Compared with non-HBC, invasive BRCA1-related HBC had a lower diploidy rate (13% vs. 35%; P = 0.002), lower mean aneuploid DNA index (1.53 vs. 1.73; P= 0.002), and strikingly higher proliferation rates (mitotic grade 3; odds ratio [OR]= 4.42; P= 0.001; aneuploid mean S-phase fraction 16.5% vs. 9.3%, P < 0.0001). Other HBC patients, including patients in two BRCA2- linked families, had more tubular-lobular group (TLG) carcinomas (OR = 2.56, P = 0.007). All trends were independent of age. A nonsignificant trend toward better crude survival in both HBC groups was age- and stage-dependent. Compared with Other HBC, BRCA1-related HBC patients had fewer recurrences (P = 0.013), a trend toward lower specific death rates, and fared no worse than breast cancer patients at large. Other HBC patients, despite neutral prognostic indicators, fared worse.

CONCLUSIONS

BRCA1-related HBCs are more frequently aneuploid and have higher tumor cell proliferation rates compared with Other HBC. Despite these adverse prognostic features, BRCA1-related HBC patients have paradoxically lower recurrence rates than Other HBC patients. The excess of TLG cancers in the "Other" HBC group may be associated with BRCA2 linkage.

Histologic types and hormone receptors in breast cancer in men: a population-based study in 282 United States men

Histologic slides from 282 incident cases of breast cancer in men, that were identified in 10 population-based cancer registries in the United States, were reviewed by a single pathologist. Breast cancer more often presented in the noninvasive stage in men (10.8 percent of all cases) than would be expected among women. All noninvasive carcinomas were of the ductal type. Of invasive carcinomas, compared with women, men had smaller proportions of lobular and mucinous types and larger proportions of ductal and papillary types and Paget's disease. No case of tubular or medullary carcinoma was seen. The breast in men is composed only of ducts and normally contains no lobules, and the histologic types of breast carcinomas that predominate in men are likely of ductal origin. Estrogen and progesterone receptors were present in 86.7 percent and 76.3 percent of invasive carcinomas, respectively, which are higher proportions than would be expected among women. Also, unlike findings in women, receptor content was not associated with patient age at diagnosis.

Histologic types of breast carcinoma in relation to international variation and breast cancer risk factors. WHO Collaborative Study of Neoplasia and Steroid Contraceptives

Associations between breast cancer risk factors and histologic types of invasive breast carcinoma were studied in 2,728 patients. Lobular and tubular carcinomas occurred with increased relative frequency in most high-risk groups. The proportion of these types increased with age to a maximum at 45-49 years and decreased in the following decade. Significantly increased proportions of lobular and tubular carcinomas were also associated with high-risk countries, prior benign breast biopsy, bilateral breast cancer, concurrent mammary dysplasia, high age at first live birth, never-pregnant patients compared to those with a first live birth before age 20, private pay status, and length of education. Nonsignificant increases were associated with family history of breast cancer, less than 5 live births, less than 25 months total of breast feeding, use of oral contraceptives or IUD, and high occupational class. As a general trend, the higher the overall relative risk, the higher the proportion of lobular and tubular carcinomas. The occurrence of other histologic types also increased with increased breast cancer risk, but to a smaller degree than for lobular/tubular carcinomas. It is suggested that all hormonally related, socio-economic and geographic risk factors exert their effect by selectively increasing number of lobular cells at risk. Family history of breast carcinoma and age over 49 years did not follow the general trend parallel increases in the proportion of lobular/tubular carcinomas and breast cancer risk, and may operate through other mechanisms.

Dual secretory and myoepithelial differentiation in the transplantable R3230AC rat mammary carcinoma

The hormone-responsive R3230AC mammary carcinoma, serially transplantable in Fisher rats, shows striking functional and morphological similarities to the normal mammary gland. We have studied its cellular composition by both light and electron microscopy, employing markers of myoepithelial and epithelial cells. We identified two cell types: the major cellular component corresponded to epithelial milk-protein secreting cells, while a second component showed immunocytochemical and ultrastructural characteristics of the myoepithelial cells. These cells were positive with a monoclonal antibody detecting alpha smooth muscle actin. The dual differentiation which normally occurs in breast ducts is therefore reproduced in a malignant experimental tumor. The coexistence of neoplastic cell populations, divergent in morphology and function, that persist in a tumor despite many transplant generations, leads to reconsideration of the relationship between cellular differentiation and malignant transformation.

Adenomyoepithelioma of the breast with a distinctive type of apocrine adenosis

A newly recognized type of dimorphic carcinoma of breast, distinct from adenoid cystic carcinoma, is described. It is characterized by a predominantly solid, clear cell myoepithelial proliferation, with centrally situated glandular lumina lined by apocrine cells. All cases arose in association with a distinctive type of atypical apocrine adenosis which has to be distinguished from microglandular adenosis and from tubular carcinoma. The biological behaviour of the tumour remains to be ascertained on the basis of longer follow-up, but it appears to have only limited malignant potential.

Kappa casein, lactalbumin and GCDFP 70 localization in human breast carcinomas: an immunohistochemical study using the avidin-biotin-peroxidase complex method

A retrospective study of 67 human breast carcinomas of various types and grades was conducted using the avidin-biotin-peroxidase complex (ABC) to localize casein, lactalbumin, and GCDFP 70 on paraffin sections. Estrogen and progesteron receptors also were evaluated. This study demonstrated the following: (1) Casein positive cells were present in all cases with a variable distribution and degree of staining, whereas lactalbumin and GCDFP 70 were seen in only 40 and 43% of the cases, respectively. (2) No significant relationship was observed between casein, lactalbumin, GCDFP 70 and the histologic types of tumors or the extent of stromal elastosis, with the exception GCDFP 70, which was observed more often in well-differentiated ductal carcinomas. (3) No significance was established in the relationship between antigens and steroid receptor content, with the exception of casein; strong casein immunostaining was significantly related to high progestin receptor levels. (4) Lactalbumin and GCDFP 70 were significantly associated with each other, but independently so of the histologic grades and types, the extent of stromal elastosis, and the steroid receptor content of the tumor cells.

Excess risk of breast cancer in the mothers of children with soft tissue sarcomas

Information was obtained on the health status or cause of death in the mothers of a population-based series of 143 children with soft tissue sarcomas. Among these mothers there were 6 cases of breast cancer. All 6 women were pre-menopausal and 2 had bilateral disease. This represents a significant 3-fold excess risk of breast cancer. Malignant disease had occurred in 6 other women whose ages at diagnosis ranged from 33 to 58 years. This was not significantly in excess of expectation. The incidence of cancer among mothers of various sub-groups of children was computed. For breast cancer mothers of: boys, children who were less than the median age at diagnosis, and children who had pelvic tumours had a greater excess risk than the group as a whole. Among those sub-groups of mothers the highest excess risk was 13.5. For other cancers, no sub-group showed an incidence which was significantly above the expected. A high proportion of infiltrating lobular carcinoma was found among the breast cancers, and histological type may indicate familial disease. These findings are consistent with the cancer family syndrome described by Li & Fraumeni in 1969, but the present results suggest that a higher proportion of childhood soft tissue sarcoma than was hitherto suspected may have a genetic aetiology. Further pedigree and laboratory studies may help to identify familial cases at the time of the child's diagnosis.

The association of cytosol oestrogen and progesterone receptors with histological features of breast cancer and early recurrence of disease

Two hundred and eighty-eight primary breast tumours were examined for the presence or absence of oestrogen (REc) and progesterone (RPc) receptors. Analysis has shown a relative interdependence between the steroid receptor status of primary breast cancer and other prognostic variables such as histological grade, lymphocytic infiltration and tumour elastosis. There were significant associations between epithelial cellularity, stromal fibrosis and the value of REc in those tumours in which the receptor was present. Cellularity and fibrosis were unrelated to the presence or absence of oestrogen receptor. By contrast, neither the presence or absence nor the value of RPc could be related to cellularity or fibrosis. The value of REc and RPc analysis as an indicator of prognosis was examined in a sub-group of 175 patients receiving no additional treatment following mastectomy. Overall relapse-free survival (RFS) was no different for those patients with receptors compared to those without them (REc P = 0.11, RPc P = 0.7). There was no difference in RFS of receptor positive and negative tumours when the axillary node status was taken into account.

Clinicopathologic hallmarks of mammary tubular carcinoma

Tubular carcinoma of the human breast is a rather uncommon neoplasm, which is characterized by particular histopathologic features and which seems to be either "scored down" (as grade I carcinoma) or overdiagnosed. Since this special variant of mammary cancer has been shown to respond more favorably to therapy than do common infiltrating carcinomas, its recognition as a genuine entity is important. Nineteen cases were studied and compared with the 110 tubular carcinomas reported in the literature. The basic clinicopathologic and histopathologic characteristics of true tubular carcinoma are discussed.

Juvenile milk protein secreting carcinoma

A case of juvenile secretory carcinoma of the breast is reported. The tumor occurred in a 19 yr-old nulliparous woman and was treated by local resection; it recurred 7 years later. Slight infiltration of the pectoral muscle, metastatic involvement of one lymph node and multifocal areas of carcinoma were found at radical mastectomy. No further recurrence has been detected after 1 year. This case confirms the slow evolution of this neoplasm but stresses that its behavior is not always as indolent as previously believed. We have used histochemical techniques for mucins (PAS, Alcian Blue) and immunoperoxidase methods for milk proteins (MFGM, beta-Casein, alpha-lactalbumin), for myoepithelial cells (actin) and for oncofetal antigens (CEA). Our results suggest that: Immunoperoxidase methods for milk proteins are a more specific and reliable marker than PAS staining in characterizing the secretory activity of juvenile carcinoma. The absence of myoepithelial cells in infiltrative areas detected by immunoperoxidase methods for actin confirms the low degree of organization in this well differentiated carcinoma of limited aggressiveness which secretes milk proteins.

Immunocytochemical detection of tumour markers in bone metastases from carcinoma of the breast

The value of immunocytochemical methods for detecting seven tumour-associated antigens was assessed in ten cases of bone metastases from carcinoma of the breast. In order to obtain the optimal preservation of both their structure and antigenicity, the biopsies were fixed-decalcified in Bouin's fluid by means of an apparatus based on ion-exchange resins recently developed in this laboratory. Of the different tumour markers, milk fat globule membrane antigen and carcino-embryonic antigen were found to be present in the majority of the cases of neoplastic cells. These two markers appear, therefore, to be the most useful for the immunocytochemical identification of metastatic neoplastic cells in the bone marrow originating from carcinoma of the breast.

Tubular carcinoma of the breast. Clinical pathologic correlations based on 100 cases

One hundred tubular carcinomas were reviewed, analyzed and compared with previously reported studies in the literature. Our cases were subdivided into five groups, according to the proportion of the carcinoma which was tubular. In the case of pure or almost pure tubular carcinomas (76% or more), tumor size was small, no metastases were found, no recurrences developed, and there were no deaths attributable to the carcinoma. As the proportion of the carcinoma which was tubular decreased, the size and biologic aggressiveness of the tumor increased; this it is likely that tubular carcinoma may represent an early form of carcinoma. A right-sided preponderance was found of the "pure tubular" carcinomas; and lesions of the central sector of the breast were rare in all five groups. The incidence of bilateral cancer was greater than that expected for breast cancer in general and included three patients with bilateral tubular carcinomas. On the basis of our findings, we suggest that lesions which are composed 90% or more of tubular carcinoma may be treated by simple mastectomy, and that axillary dissection is not necessary. For all carcinomas with a lower proportion of tubular elements, at least total mastectomy and axillary dissection are indicated, although the safest treatment probably is radical mastectomy.

Tubular carcinoma developing within a recurring cystosarcoma phyllodes of the breast

Malignant alteration in cystosarcoma phyllodes is uncommon and almost always confined to the stromal component. A rare case of recurring cystosarcoma is reported. In the first recurrence, lobular carcinoma in situ was present within the tumor and the second recurrence revealed tubular carcinoma within the cystosarcoma. Epithelial proliferation of various sorts is not uncommon in cystosarcomas but only two previous instances of infiltrating carcinoma have been observed within these tumors. The problem of mammary carcinoma coexisting with cystosarcoma is reviewed and comparisons are made with a closely related neoplasm, the fibroadenoma.

Invasive lobular carcinoma of the breast: incidence and variants

The criteria for the separation of invasive lobular and ductal carcinomas are analysed. Lobular tumours account for 14% of invasive cancers in our material. The widely differing figures given in the literature are mainly attributable to intrinsic difficulties of classification. In addition to the classical dissociated-cell patterns with single filing, a tragetoid appearance and related features, variants with trabecular, loose alveolar and tubular features are recognized; a 'solid' variant requires further investigation. The variants either represent better differentiated forms, or in some cases, an 'earlier' phase in the production of the more traditional Indian file formations and dartboard patterns. Focal signet-ring cell differentiation is another newly-recognized feature. The theoretical and practical implications of these variants are considered. The division into invasive lobular and ductal carcinomas is not as easy as most of the literature implies. Five per cent of cases could not be so classified and, in some of these unclassified cases, both ductal and lobular differentiation may be present. In the diagnosis of problem cases, no single parameter proved reliable but a combination of several parameters enables one to make an objective diagnosis in about 95% of cases.