Oestrogen receptor and epidermal growth factor receptor expression in male breast carcinoma

Male patient with metastatic stage IV breast cancer achieves complete remission on second line Abemaciclib, Fulvestrant and Leuprolide: A case report

Male breast cancer occurs rarely, comprising <1% of breast cancers. Due to the low incidence of male breast cancer, clinical trials of this disease are lacking. Therefore, therapeutic strategies utilized in the management of female breast cancer are often applied to male patients with breast cancer. Specifically, clinical outcomes using CDK 4/6 inhibitors require further investigation in male patients. To the best of our knowledge, the present report presents the first known case of a male patient treated with second line Abemaciclib, Lupron and Fulvestrant, producing complete remission. To the best of our knowledge this is also the first report of complete remission in a male breast cancer patient with a regimen utilizing a CDK 4/6 inhibitor.

The Epidemiology of Male Breast Cancer

Male breast cancer is a rare disease, accounting for only 1% of breast cancer diagnoses in the USA. The current literature suggests that genetic factors including BRCA2 mutations, family history, age, androgen/estrogen imbalance, and environmental exposures may predispose to male breast cancer. In this manuscript, we will review known and possible risk factors for male breast cancer, as well as describe the clinical patterns of the disease.

The Management and Outcomes of Male Breast Cancer

OBJECTIVE

Due to a lack of sufficient data, the treatment protocols for male breast cancer are usually the same as those used for female breast cancer. The aim of the current study was to present our clinical experience with male breast cancer.

MATERIALS AND METHODS

The records of 37 patients who were treated for male breast cancer in our hospital between 2004 and 2014 were reviewed retrospectively. The data of patients were recorded and analyzed.

RESULTS

The mean age of the patients was 63.03±12.36 years. Thirty-three patients (89.2%) had invasive ductal carcinoma, two (5.4%) had ductal carcinoma in situ, and two had invasive lobular carcinoma (5.4%). The most common molecular subtype was luminal A (17 cases, 45.9%). Twenty-nine patients with male breast cancer underwent mastectomy and two underwent breast conserving surgery. Axillary lymph node dissection was performed in 25 patients. The most common surgical procedure was modified radical mastectomy. Distant metastases were present in 17 (45.9%) patients. Overall, the 5-year survival was 60%. The 5-year survival was 100% for those with stage 0-I disease, 87% for stage II, and 42% for stage III. The 3-year survival was 14% for stage IV.

CONCLUSION

Patients with male breast cancer presented at an older age, a later stage, and with earlier metastasis. Early metastasis and death increases with increasing stage. Poor prognosis correlates with late admission. Data from different centers should be compiled and reviewed in order to determine a specific treatment protocol for male breast cancer; each paper published reveals new data.

Male breast cancer: risk factors, biology, diagnosis, treatment, and survivorship

BACKGROUND

The causes, optimal treatments, and medical/psychosocial sequelae of breast cancer in men are poorly understood.

DESIGN

A systematic review of the English language literature was conducted to identify studies relevant to male breast cancer between 1987 and 2012 and including at least 20 patients. Searches were carried out on PubMed using the title terms 'male breast cancer' or 'male breast carcinoma'.

RESULTS

Relevant published data regarding risk factors, biological characteristics, presentation and prognosis, appropriate evaluation and treatment, and survivorship issues in male breast cancer patients are presented. BRCA2 mutations, age, conditions that alter the estrogen/androgen ratio, and radiation are proven risk factors. Disease biology is distinct in men, but diagnostic approaches and treatments for men are generally extrapolated from those in women due to inadequate research in men. Survivorship issues in men may include sexual and hormonal side-effects of endocrine therapies as well as unique psychosocial impacts of the disease.

CONCLUSION

Further research is needed to address gaps in knowledge pertaining to care of male breast cancer patients and survivors.

Differential expression of growth factor receptors and membrane-bound tumor markers for imaging in male and female breast cancer

Introduction

Male breast cancer accounts for 0.5–1% of all breast cancers and is generally diagnosed at higher stage than female breast cancers and therefore might benefit from earlier detection and targeted therapy. Except for HER2 and EGFR, little is known about expression of growth factor receptors in male breast cancer. We therefore investigated expression profiles of growth factor receptors and membrane-bound tumor markers in male breast cancer and gynecomastia, in comparison with female breast cancer.

Methods

Tissue microarrays containing 133 male breast cancer and 32 gynecomastia cases were stained by immunohistochemistry for a panel of membrane-bound targets and compared with data on 266 female breast cancers.

Results

Growth factor receptors were variably expressed in 4.5% (MET) up to 38.5% (IGF1-R) of male breast cancers. Compared to female breast cancer, IGF1-R and carbonic anhydrase 12 (CAXII) were more frequently and CD44v6, MET and FGFR2 less frequently expressed in male breast cancer. Expression of EGFR, HER2, CAIX, and GLUT1 was not significantly different between male and female breast cancer. Further, 48.1% of male breast cancers expressed at least one and 18.0% expressed multiple growth factor receptors. Since individual membrane receptors are expressed in only half of male breast cancers, a panel of membrane markers will be required for molecular imaging strategies to reach sensitivity. A potential panel of markers for molecular imaging, consisting of EGFR, IGF1-R, FGFR2, CD44v6, CAXII, GLUT1, and CD44v6 was positive in 77% of male breast cancers, comparable to female breast cancers.

Conclusions

Expression patterns of growth factor receptors and hypoxia membrane proteins in male breast cancer are different from female breast cancer. For molecular imaging strategies, a putative panel consisting of markers for EGFR, IGF1-R, FGFR2, GLUT1, CAXII, CD44v6 was positive in 77% of cases and might be considered for development of molecular tracers for male breast cancer.

Prognostic indicators in male breast carcinoma

Twenty-nine male breast cancers (MBC) were studied to determine the relationship between expression of several prognostic factors and clinical outcome. Immunohistochemistry employing a labeled streptavidin-biotin method was used to detect the presence of estrogen (ER) and progesterone receptors (PR), cathepsin D (CD), c-erbB-2 oncoprotein, epidermal growth factor receptor (EGFR), and p53; results were visually semiquantitated. DNA ploidy was evaluated by image analysis (CAS 200) of 5 μm fixed embedded Feulgenstained tissue sections. For proliferating cell nuclear antigen (PCNA), nuclear immunostain was quantitated as percentage positive nuclear area (PPNA) by image cytometry (CAS 200). The frequency of expression was ER, 26/29 (89.7%); PR, 19/29 (65.5%); CD, 25/29 (86.2%); c-erbB-2, 5/29 (17.2%); EGFR, 4/29 (13.8%); and p53, 9/29 (31%). Twenty-one (72.4%) were aneuploid; the mean PPNA for PCNA was 37.87% (control 13%). Of 20 patients, 10 (50%) MBC had lymph node metastases; 6 (21%) had distant metastases to lung (1) and bone (5). Five of the patients died of MBC. Excluding the patients with only ductal carcinoma in situ, the 1-and 5-year survival rates were 90.5% and 56.3%, respectively. In this comprehensive study of a large number of available prognostic markers, their frequency (with the exception of higher ER and CD) and prognostic significance were similar to that in female breast carcinoma. Among clinical and standard pathologic unfavorable prognostic indicators, age ≥ 62 years was significant (p = .004). Trends toward reduced survival were associated with axillary lymph node metastases (p = .145), ER negativity (p = .058), PR negativity (p = .116), and aneuploid DNA content (p = .201).

Immunohistochemical characterization of subtypes of male breast carcinoma

Introduction

Male breast cancer accounts for around 1% of all breast cancer cases but the incidence has risen in recent years. This study aimed to classify the molecular subtypes of male breast cancers based on the expression profile of immunomarkers and to evaluate their association with clinicopathological features and expression patterns of epidermal growth factor receptor (EGFR) and nuclear factor κB (NF-κB).

Methods

A total of 42 cases of male breast carcinoma were examined retrospectively using immunostains for estrogen receptor (ER), progesterone receptor (PR), cytokeratin 5/6 (CK5/6), EGFR, and NF-κB. Human epidermal growth factor receptor 2 (HER2) expression was evaluated by immunostaining and confirmed by fluorescent in situ hybridization (FISH).

Results

The luminal A subtype was the most common subtype in male breast cancer (83%, 35/42), which was followed by the luminal B subtype (17%, 7/42). Basal-like and HER2+/ER- subtypes were not identified in this group. All carcinomas expressed ER and 67% of them were PR+. High nuclear grades were more common in the luminal B subtype (71%, 5/7) than in the luminal A subtype (34%, 12/35). The luminal B subtype carcinomas expressed EGFR (42%, 3/7) and NF-κB (57%, 4/7) more frequently than the luminal A subtype did (17%, 6/35 and 37%, 13/35, respectively).

Conclusions

In our study group, luminal A and B subtypes were the major subtypes of male breast carcinoma. The immunophenotypical features of male breast cancer differ from those of its female counterpart. Luminal B subtype tended to have high nuclear grade and more frequent expression of EGFR and NF-κB.

Male breast cancer: a gender issue

The incidence of male breast cancer (MBC) is rising; however, mortality due to MBC has not changed, unlike female breast cancer. This lack of change is mostly attributable to a lack of major progress in the understanding and treatment of the disease. The treatment of MBC has been extrapolated from the knowledge of female breast cancer, despite the multiple differences in the pathogenesis, biology and genetics of these two disease entities, especially the differences with regard to the role of male hormones as well as estrogens in MBC compared with female disease. Although major advances in hormonal manipulation for the treatment of breast cancer are being developed, an improved understanding of the potential differences between male and female breast cancer is essential, as this would provide new opportunities for therapeutic intervention and probable improved outcome for MBC. This review aims at highlighting the major differences between male and female breast cancer with an emphasis on hormonal therapy, and discusses some of the recent advances in MBC.

Hormone receptor expression in male breast cancers

SummaryMale breast cancers are rare but have been found in higher proportions in Black Africans. Prognostic factors for breast cancers include tumour size, grade and stage, and hormone receptor status. The hormone receptor status is an invaluable guide in the use of adjuvant endocrine therapy, but none of the reports available in the literature from Africa showed any receptor work.This study was conducted to determine the grade, lymph node status and hormone receptor status of male breast cancers in Ghana.Nine archival cases of male breast cancers from the Pathology Department of Korle Bu Teaching Hospital were selected and studied on the basis of the presence of enough material for immunocytochemistry. Haematoxylin and Eosin (H & E) stained slides were reviewed and graded by Bloom and Richardson's criteria. Lymph node status was also assessed and sections were stained for oestrogen and progesterone receptors.Seven of the nine tumours were invasive ductal carcinomas and six of these were grade II, and one was grade III. Four cases had axillary lymph nodes removed at surgery and three were positive for metastases. Six (66%) of the cases were positive for oestrogen receptors with an H score ranging from 20 to 300. Using the criteria of McCarty et al, positivity for oestrogen receptor was reduced to 44%, which is lower than for Caucasians. We believe that this may be explained by the fact that in Ghana male breast cancers are seen a decade earlier. Only two cases were positive for progesterone receptor with an H score of 10 and 75. The two cases positive for progesterone receptors were also positive for oestrogen receptors.It is concluded that hormone receptor study is important in deciding on endocrine and adjuvant chemotherapy in male breast cancers and should be done routinely to help surgeons plan postoperative management of these patients. We recommend further research in this area.

Detection and purification of a novel 72 kDa glycoprotein male breast tumor associated antigen

A male breast tumor associated antigen (MBTAA) was purified and partially characterized from human male breast tumor. Three protein peaks were obtained by DEAE-cellulose column chromatography of a crude extract of human male breast tumor tissues. Circulating antibodies against one of these peaks, MF1, which contained MBTAA, were observed in male breast cancer patients but not in normal male or male patients with carcinoma of other organs (stomach, colon, lung). The MBTAA was partially purified from MF1 by subjecting the fraction to SDS-PAGE and eluting the protein from band 3 (MB-3) and by subjecting MF1 to size exclusion-high performance liquid chromatography (SE-HPLC). The MBTAA was characterized as a glycoprotein with MW of approximately 72 kDa. It showed no immunological relatedness with TAG-72, a tumor associated antigen expressed in breast epithelial cells. A 72 kDa protein, immunologically related to MBTAA, was detected and partially purified from female breast tumor. The female breast cancer patients did not have circulating antibodies against this 72 kDa protein or MBTAA. Presence of 72 kDa glycoprotein MBTAA in MF1 and specificity of the anti-MBTAA antibodies in the sera of male breast cancer patients were further confirmed by Western blot analysis. Absence of anti-MBTAA antibodies in healthy men and in patients with other cancers suggested that expression of MBTAA may be malignancy-associated and is highly overexpressed in male breast cancer.

Hormone receptors in breast cancer: racial differences in distribution and survival

The purpose of this study was to describe hormone receptor status and analyze the effect of receptors on survival from breast cancer. Comparisons were made between African-American and Caucasian racial categories. Breast cancer data from 1990 through 1997 collected by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program were analyzed. Subjects were 993 Caucasian men, 12,303 African-American women, and 141,045 Caucasian women. The number of African-American men was too small to analyze separately (n = 93). In addition to analysis of estrogen and progesterone receptor status by sex and race, tumor and patient characteristics included age, stage at time of diagnosis, and tumor histology. The proportion of Caucasian men with hormone receptor positive tumors remained relatively high and stable for all ages. In women, the proportion of hormone receptor positive tumors increased with age, with African-American women having the highest proportion of hormone receptor negative tumors. Caucasian men had highest proportions of hormone receptor positive tumors in all histology and stage groups, while African-American women had lowest proportions of hormone receptor positive tumors in all stage and histologic categories. Survival for African-American women was significantly worse for each hormone receptor category. In multivariate analyses, race was a significant independent predictor of survival, but sex was not. Although reasons for differences in hormone receptor status by sex and race are unknown, several hypotheses are discussed with respect to differences in tumor histopathology and risk factors.

Androgen receptor expression in male breast carcinoma: lack of clinicopathological association

Androgen receptor (AR) expression was retrospectively analysed in 47 primary male breast carcinomas (MBCs) using a monoclonal antibody on formalin-fixed, paraffin-embedded tissues. AR immunopositivity was detected in 16 out of 47 (34%) cases. No association was found with patient age, tumour stage, progesterone receptor (PGR) or p53 protein expression. Well-differentiated MBCs tended to be AR positive more often than poorly differentiated ones (P = 0.08). A negative association was found between ARs and cell proliferative activity: MIB-1 scores were higher (25.4%) in AR-negative than in AR-positive cases (21.11%; P = 0.04). A strong positive association (P = 0.0001) was found between ARs and oestrogen receptors (ERs). In univariate analysis, ARs (as well as ERs and PGRs) were not correlated with overall survival; tumour histological grade (P = 0.02), size (P = 0.01), p53 expression (P = 0.0008) and MIB-1 scores (P = 0.0003) had strong prognostic value. In multivariate survival analysis, only p53 expression (P = 0.002) and histological grade (P = 0.02) retained independent prognostic significance. In conclusion, the lack of association between AR and most clinicopathological features and survival, together with the absence of prognostic value for ER/PGR status, suggest that MBCs are biologically different from female breast carcinomas and make it questionable to use antihormonal therapy for patients with MBC.

Molecular markers in male breast carcinoma

BACKGROUND

In contrast to female breast carcinoma, information regarding the prevalence and prognostic information of new molecular markers is limited in male breast carcinoma. The objective of this study was to assess the degree of expression and prognostic value of estrogen receptors (ER), progesterone receptors (PR), androgen receptors (AR), bcl-2, p53, HER-2/neu, cyclin D1, and MIB-1 in a cohort of male breast carcinoma patients.

METHODS

A computerized search of the medical index, tumor registry, and tissue registry was used to identify 111 male patients with a diagnosis of primary adenocarcinoma of the breast seen between 1950-1992 at the Mayo Clinic. Of these, 77 patients had adequate tissue specimens available for the immunohistochemical analysis of the markers. Immunoperoxidase staining was performed by an automated avidin-biotin complex method. Progression free (PFS) and overall (OS) survival distributions were estimated using the Kaplan-Meier method. The log rank test was used to determine whether any patient characteristic, tumor feature, or molecular marker was associated significantly with PFS or OS.

RESULTS

The majority of tumor specimens were positive for ER (91%), PR (96%), AR (95%), and bcl-2 (94%). Fewer positive specimens were found for cyclin D1 (58%), MIB-1 (38%), HER-2/neu (29%), and p53 (21%). The 5-year PFS and 10-year OS for the entire patient cohort was estimated to be 66% (95% confidence interval [CI], 57-77%) and 38% (95% CI, 29-50%), respectively. PFS was decreased significantly for those patients with tumors staining positively for MIB-1 (P=0.012) or negatively for cyclin D1 (P=0.009). OS was not found to differ significantly with respect to these markers.

CONCLUSIONS

The nearly universal expression of hormone receptors in these tumors suggests a central role for endogenous hormones in male breast carcinoma. The high degree of AR expression would suggest that antiandrogen therapy should be explored further. The high frequency of bcl-2 positivity may implicate antiapoptotic mechanisms in the carcinogenesis of male breast carcinoma. The finding of decreased PFS in MIB-1 positive tumors supports the role of proliferative activity as a negative prognostic factor in male breast carcinoma. Positive cyclin D1 expression is associated with increased PFS in male breast carcinoma patients, which suggests that interactions among cell cycle regulatory proteins may be important in this disease.

Intratumoral aromatase in human breast, endometrial, and ovarian malignancies

In human estrogen-dependent neoplasms such as breast, endometrioid endometrial, and surface epithelial-stromal ovarian carcinomas, intratumoral aromatase is considered to play important roles in converting circulating androgens derived from adrenal cortex and/or ovary to estrogens, possibly in association with 17 beta-HSD type 1 and estrogen sulfatase. Analysis of intratumoral aromatase in these estrogen-dependent neoplasms is important not only in understanding the development and biological behavior of these tumors, but also in the clinical management of these patients, because suppression of intratumoral aromatase by newly developed aromatase inhibitors may provide new potentials in endocrine therapy of these patients.

Male breast cancer: a review of the literature

Although breast cancer is uncommon in men, it can cause significant morbidity and mortality. The current review was undertaken to determine whether strategies applied for the evaluation and treatment of breast cancer in females are appropriate in male breast cancer. Male breast cancer has biological differences compared with female breast cancer, including a high prevalence in certain parts of Africa, a higher incidence of oestrogen receptor positivity and more aggressive clinical behaviour. It responds to hormonal manipulation and chemotherapy, but optimal treatment regimens in males are unknown. Male breast cancer remains an uncommon disease. Most of our current knowledge regarding its biology, natural history and treatment strategies has been extrapolated from its female counterpart. Much research is needed to further characterise the molecular biological properties of male breast tumours and their prognostic significance, and to devise treatment strategies, including optimal chemotherapy regimens.

A comparison outcome of male breast cancer with female breast cancer

BACKGROUND

It is unclear whether breast cancer has a similar prognosis in males and females.

METHODS

A 20-year retrospective study of all male breast cancer patients in our region was undertaken. We compared this series with a group of females matched for the major prognostic factors and an unmatched series of female patients treated over the same period.

RESULTS

Forty-one patients with invasive cancer and 2 with ductal carcinoma in situ were identified. One invasive cancer was treated with radiotherapy, 40 had surgery. Local recurrence occurred in 23% and axillary recurrence in 40% of cases. Male and female patients (n = 123) matched for the major prognostic factors showed a similar outcome for disease-free interval (P = 0.90) and survival (P = 0.27). However, both the above groups had a significantly worse outcome than the unmatched series of female patients with breast cancer.

CONCLUSIONS

When prognostic factors are allowed for, male and female breast cancer patients have a similar outcome. This suggests that such features should be taken into account when determining management for males with breast cancer just as they are in females.

Lack of relationship between the expression of Hsp27 heat shock estrogen receptor-associated protein and estrogen receptor or progesterone receptor status in male breast carcinoma

Estrogen, through estrogen receptors (ERs), may regulate the synthesis of progesterone receptors (PRs) and of a heat shock estrogen receptor-associated protein (hsp27). In female breast carcinoma (FBC) both proteins serve as surrogate indicators for the presence of functional ERs. In addition, the expression of these proteins was related to other prognostic indicators of value in female breast tumours. Endocrine disorders, hormone therapy and altered estrogen metabolism have been associated with the development of male breast cancer (MBC), suggesting that evaluation of the expression of ER, PR and hsp27 might improve our understanding of the biology of this tumour. ER and PR status and hsp27 expression were evaluated by immunohistochemistry in 16 primary MBC patients. The interrelationships between these parameters were established and compared with the clinicopathological data on the tumours. Ten (56%) MBC patients were ER-positive, 69% were PR-positive and all samples were hsp27-positive. Our series of MBC patients showed a positive correlation between ERs and PRs, however there was a lack of correlation between hsp27 and ERs or PRs. MBCs did not exhibit any correlation between the biomarkers studied and known prognostic indicators for females (e.g. Scarff-Bloom-Richardson (SBR) or modified SBR (MSBR) grade, T stage, lymph node status). This is the first published series reporting the incidence of hsp27 in MBC. The lack of association between the expression of ERs and hsp27 found in MBC differs from the results reported for FBC, moreover the expression of ERs, PRs or hsp27 did not correlate with the clinicopathological parameters that have prognostic value in females. Although the data were obtained from a relatively small sample population, our findings suggest that MBC and FBC are biologically different tumours with respect to the expression of the studied proteins.

Male breast cancer: a retrospective study with immunohistochemical analysis of hormone receptor expression

Of twenty-two cases of breast carcinoma diagnosed in men in Singapore since 1969, 17 were classified as infiltrative ductal carcinoma, three as papillary and one as mucinous carcinoma. The remaining case could not be classified and further immunohistochemical workup suggested the possibility of metastasis from an occult prostatic primary. Fourteen cases that were staged revealed a majority of seven (50%) cases in Stage II, with three (21%) Stage I, one (8%) Stage III and three (21%) Stage IV cases. Estrogen and progesterone receptor (ER and PR) expression was determined in 20 cases using immunohistochemical staining of archival paraffin embedded tissue blocks, which demonstrated ER and PR positivity in 65% of the cases respectively.

Comparison of prognostic markers detected by immunohistochemistry in male and female breast carcinomas

Male infiltrating breast carcinomas are rare and seem to have different characteristics, prognosis and sensitivity to hormonal treatment than those of female breast carcinomas. Our aim was to determine whether markers which have an established role in women are also important in men. 66 male infiltrating-ductal breast carcinomas were compared with 190 female breast carcinomas of the same type. Various markers were studied using immunohistochemistry. Tumour size at diagnosis, grade, number of axillary metastases and prognosis were comparable in male and female breast carcinomas. However, male breast carcinomas were characterised by a higher percentage of oestrogen receptor (OR) reactivity, and weekly associated with markers that, in women, are under oestrogen control. Male breast carcinomas were positive for markers under androgen control. Male breast carcinomas also differed from female carcinomas by the low percentage of p53+ and the high percentage of bcl-2+ tumours. The phenotype of male breast carcinomas has characteristics that could have repercussions on prognosis and on the choice of hormonal treatment. Only a few male breast cancers are p53+. OR, which are frequently present in male tumours, are probably not functional. In contrast, androgen receptors seem efficient, as several markers under androgen control are expressed. Therefore, the selection of hormonal therapy should not be based on OR status only.

Male breast cancer: clinico-pathological features, immunocytochemical characteristics and prognosis

A series of 30 cases of male breast cancer in the North-East of Scotland is reviewed. The aims of the study were to document clinico-pathological and immunocytochemical features (available for 25) of these patients and to establish which factors could predict prognosis. Tumours were studied for the expression of oestrogen receptors (ERs), the oestrogen-dependent proteins pS2 and cathepsin D, the oncoprotein products of c-erb-B2 and the p53 tumour-suppressor-gene derived protein. Clinico-pathological features documented were in agreement with those reported by other authors. The overall 5-year survival was 53%. Tumour grade and lymph-node status influenced prognosis. In this series, 64% of the tumours expressed ERs, 50% pS2, 46% cathepsin D, 42% the c-erb-B2 transmembrane oncoprotein and 54% p53. In contrast to female breast cancer, the presence of either substantial amounts of ERs or the oestrogen-dependent protein pS2 correlated with poorer prognosis in males. This correlation has not previously been documented.

Prevention of spontaneous tumours in female rats by fadrozole hydrochloride, an aromatase inhibitor

Mammary tumours are oestrogen dependent in female Sprague-Dawley rats and in a significant proportion of women, so pharmacological treatment to inhibit oestrogen production is a valuable therapeutic measure to prevent or slow the progression of disease. Here we show that a non-steroidal aromatase inhibitor, which competitively inhibits the conversion of androstenedione to oestrone, prevents the development of both benign and malignant spontaneous mammary neoplasms in female Sprague-Dawley ats. It also slows the spontaneous development of pituitary pars distalis adenomas in female rats, and reduces the incidence of spontaneous hepatocellular tumours in male and female rats.

Carcinoma of the male breast: update 1994

In many ways, male and female breast cancers are similar, but do have some notable differences. Although the underlying etiology of male breast cancer may be partially due to hormonal or environmental changes, this disease is rare compared to female breast cancer. Most often, it presents as a painless lump, with estrogen receptor-positive infiltrating ductal carcinoma being the most common pathologic type. The main component of local therapy is either a radical or a modified radical mastectomy, with adjuvant chemotherapy proving useful. Estrogen receptor-positive tumors respond well to hormonal therapy. More research is needed in order to: (1) further characterize the molecular biological properties of male breast cancer tumors, (2) further investigate the role of adjuvant chemotherapy, and define successful regimens, and (3) determine optimal chemotherapy regimens in the treatment of metastatic disease. As this disease is a relatively rare condition, whenever possible, all patients should be allowed to participate in national cooperative group studies.

Retrospective analysis of prognostic significance of the estrogen-inducible pS2 gene in male breast carcinoma

BACKGROUND

The estrogen-inducible pS2 gene, originally isolated from a breast cancer cell line, is correlated with hormone-dependent female breast tumors and its expression is associated with longer overall and disease-free survival.

METHODS

The authors have investigated 38 samples of carcinomas of the male breast for pS2 expression by using a monoclonal antibody. The immunostaining was compared with clinical data, in particular, to the progesterone receptor status, to assess a possible prognostic value of this parameter.

RESULTS

Although most cases (27 of 38) were immunopositive (i.e., above the 5th percentile of immunoreactive cells), no correlation with tumor grade and survival was notable.

CONCLUSIONS

Therefore, on the contrary to the situation in female breast cancer, pS2 activity failed to constitute a new prognostic parameter in male breast carcinomas.

Expression of cathepsin D and estrogen receptor in male breast carcinoma

Male breast cancer is probably hormone dependent, but studies are few due to the rarity of this tumor. We have studied 21 cases of male breast cancer immunohistologically for estrogen receptor (ER) and cathepsin D (CD) expression. In carcinoma of the female breast ER expression is associated with longer patient survival and responsiveness to hormonal manipulation. Cathepsin D is an estrogen-regulated lysosomal protease with proteolytic and mitogenic properties whose presence denotes a functioning ER. In our series of male breast carcinomas 86% were ER positive and 62% were CD positive; this compares with typical figures of 50% and 66%, respectively, for female breast cancer. We observed no trends between expression of ER and CD and patient survival; immunostaining for ER and CD is unlikely to be clinically useful in carcinoma of the male breast. The high rate of ER positivity in males suggests that male and female breast carcinomas are biologically different tumors.