Clinicopathological feature and long-term prognosis of apocrine carcinoma of the breast in Japanese women

Malignant Apocrine Lesions of the Breast: Multimodality Imaging Findings and Biologic Features

The apocrine morphology of the breast is observed in a broad pathological spectrum, ranging from benign cysts to invasive carcinomas. However, the number of clinical research investigating malignant apocrine lesions is limited. This study retrospectively reviewed the data of patients with malignant apocrine lesions admitted in a tertiary center between January 2004 and December 2021, based on the radiology-pathology correlation and the recent advances in their status to enhance the therapeutic implications of androgen receptor (AR). Among the 37 patients with lesions, 27 (73.0%) had triple-negative subtypes with predominant AR expression. The radiological features of malignant apocrine lesions did not differ from those of typical invasive ductal carcinoma or ductal carcinoma in situ. This study demonstrated that knowledge on the imaging features of malignant apocrine lesions and their histological basis could enhance the adoption of new targeted therapies in patients with this particular type of breast cancer.

Triple-negative apocrine carcinoma: A rare pathologic subtype with a better prognosis than other triple-negative breast cancers

BACKGROUND AND METHODS

Apocrine adenocarcinoma is a rare subtype of breast cancer. We sought to compare the characteristics and survival of patients diagnosed with triple-negative apocrine adenocarcinoma to those of patients diagnosed with triple-negative invasive ductal carcinoma. Utilizing data from the National Cancer Database between 2004 and 2013, 70 524 eligible female patients with triple-negative breast cancer were identified including 566 patients with apocrine adenocarcinomas and 69 958 patients with invasive ductal carcinoma. Descriptive statistics for each variable were reported. A comparison of each covariate between the study cohorts was assessed in univariate and multivariate analysis. Cox proportional models were used to calculate hazard ratios. Additionally, the propensity score matching method was implemented to reduce treatment selection bias.

RESULTS

Patients with triple-negative apocrine tumors were more likely to be older, Caucasian, and have smaller, moderately to well-differentiated tumors. Multivariable analysis noted a significantly improved survival for patients with triple-negative apocrine carcinoma (TNAC) vs triple-negative invasive ductal carcinoma (TNBC) (hazard ratio [HR] 0.65 [95% confidence interval [CI] [0.53-0.81], P = 0 < .001). Propensity score matching analysis confirmed a significant difference in overall survival for patients with TNAC in comparison to TNBC (HR 0.79 [95% CI [0.63-1.00], P = .05).

DISCUSSION

Triple-negative apocrine adenocarcinomas have a modestly improved long-term survival when compared with triple-negative invasive ductal cancers.

Prognosis of selected triple negative apocrine breast cancer patients who did not receive adjuvant chemotherapy

Background

Triple negative breast cancer encompasses several biological entities with different outcomes and is a priority to identify which patients require more treatment to reduce the risk of recurrence and which patients need less treatment.

Patients and methods

Among the 210 women with first primary invasive apocrine non metastatic breast cancer operated on between January 1998 and December 2016 at the European Institute Oncology, Milan, we identified 24 patients with a pT1-pT2, node-negative, triple negative subtype and Ki-67 ≤ 20% who did not receive adjuvant chemotherapy (CT). We compared the outcome of this cohort with a similar group of 24 patients with ductal tumors who received adjuvant chemotherapy, matched by pathological stage and biological features and also with a similar group of 12 patients with apocrine tumors who received adjuvant chemotherapy.

Results

The median age was 64 and 61 years in the apocrine (w/o CT) and ductal group, respectively. The median value of Ki-67 expression was 12% in the apocrine group (w/o CT) and 16% in the ductal group (p < 0.001). After a median follow-up of 7.5 years, no patients in the apocrine group (w/o CT) experienced a breast cancer related event compared with 4 events in the ductal carcinoma group (Gray test p-value = 0.11).

Conclusions

The outcome of selected apocrine triple negative breast cancer patients who did not received adjuvant chemotherapy is excellent and supports a treatment de-escalation. Multicenter projects focusing on the possibility of avoiding adjuvant chemotherapy in selected subtypes of triple negative breast cancers with favorable outcome are warranted.

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Triple negative breast cancer is a eterogeneous disease.

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The outcome of selected apocrine triple negative breast cancer patients is excellent despite the omission of chemotherapy.

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A treatment de-escalation should be discussed.

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Multicenter projects focusing on selected subtypes of triple negative breast cancers are warranted.

Histologic subtyping affecting outcome of triple negative breast cancer: a large Sardinian population-based analysis

BACKGROUND

Triple Negative breast cancer (TNBC) includes a heterogeneous group of tumors with different clinico-pathological features, molecular alterations and treatment responsivity. Our aim was to evaluate the clinico-pathological heterogeneity and prognostic significance of TNBC histologic variants, comparing "special types" to high-grade invasive breast carcinomas of no special type (IBC-NST).

METHODS

This study was performed on data obtained from TNBC Database, including pathological features and clinical records of 1009 TNBCs patients diagnosed between 1994 and 2015 in the four most important Oncology Units located in different hospitals in Sardinia, Italy. Kaplan-Meier analysis, log-rank test and multivariate Cox proportional-hazards regression were applied for overall survival (OS) and disease free survival (DFS) according to TNBC histologic types.

RESULTS

TNBC "special types" showed significant differences for several clinico-pathological features when compared to IBC-NST. We observed that in apocrine carcinomas as tumor size increased, the number of metastatic lymph nodes manifestly increased. Adenoid cystic carcinoma showed the smallest tumor size relative to IBC-NST. At five-year follow-up, OS was 92.1, 100.0, and 94.5% for patients with apocrine, adenoid cystic and medullary carcinoma, respectively; patients with lobular and metaplastic carcinoma showed the worst OS, with 79.7 and 84.3%, respectively. At ten-years, patients with adenoid cystic (100.0%) and medullary (94.5%) carcinoma showed a favourable prognosis, whereas patients with lobular carcinoma showed the worst prognosis (73.8%). TNBC medullary type was an independent prognostic factor for DFS compared to IBC-NST.

CONCLUSIONS

Our study confirms that an accurate and reliable histopathologic definition of TNBC subtypes has a significant clinical utility and is effective in the therapeutic decision-making process, with the aim to develop innovative and personalized treatments.

Prognosis in triple-negative apocrine carcinomas of the breast: A population-based study

Background

Triple‐negative apocrine carcinoma (TNAC) of the breast is a very rare type of breast cancer. Furthermore, the clinicopathological features, prognosis, and potential impact of treatment strategies in TNAC remain unclear.

Methods

Data from the Surveillance, Epidemiology, and End Results (SEER) program were used to identify breast cancer patients diagnosed between 2010 and 2016 with TNAC and triple‐negative breast cancer (TNBC, IDC [invasive ductal carcinoma], NOS [not otherwise specified]). Chi‐squared tests were used to examine the categorical variables between the two groups. Overall survival (OS) of TNAC and TNBC was assessed by Kaplan‐Meier analyses and Cox regression. Breast cancer‐specific survival (BCSS) was evaluated by Nelson‐Aalen analyses and competing risk regression.

Results

We identified 31 362 patients from the SEER database, including 366 patients with TNAC and 30 996 patients with TNBC. TNAC was correlated with older age, lower T stage and lower tumor grade. Patients with TNAC had better OS compared with TNBC patients; the 5‐year OS rates were 82.2% vs 73.5% (P < .001). The breast cancer‐related death rate was significantly lower in patients with TNAC than in patients with TNBC, with a 5‐year cumulative incidence of 9.1% vs 22.9% (P < .001). Chemotherapy was significantly associated with improved OS in TNAC patients, but radiotherapy was not associated with OS in TNAC patients. In the multivariable Cox regression, TNAC was still associated with improved OS (HR [hazard ratio], 0.61; 95% CI [confidence interval] 0.45‐0.83; P = .002). In the multivariable competing risk regression, the significantly higher BCSS in patients with TNAC compared patients with TNBC remained (subdistribution HR [SHR], 0.42; 95% CI, 0.27‐0.64; P < .001).

Conclusion

Patients with TNAC had a better prognosis than patients with TNBC, and chemotherapy was associated with survival advantages in TNAC patients.

The role of histopathologic testing on apocrine carcinoma of the breast

BACKGROUND

Apocrine carcinoma is a rare primary breast tumor characterized by the apocrine morphology. The purpose of this article is to report a review of cases with apocrine carcinoma and draw physicians' attention to the benefits of immunphenotypic techniques in cases with suspected apocrine morphology in diagnosing this uncommon breast tumor.

METHODS

In this study, authors report a case series of 15 cases with apocrine carcinoma from totally 4123 breast cancer cases. Data collected between years 2008 and 2016 from Istanbul School of Medicine department of surgery archive by analyzing surgical approach to cases and immunphenotypic features of tumors according to the date of examining in our pathology department.

RESULTS

In this study, Androgen, "gross cystic disease fluid protein-15" (GCDFP-15), estrogen (ER), progesterone (PR) and Her-2 neu receptor status supported evidence of apocrine carcinoma has been reviewed. As a result, HER-2 neu, GCDFP-15, androgen receptor positivity in general are useful in the diagnosis of apocrine carcinoma. In addition of these data our study revealed that GCDFP-15 positive patients are more prone to have local recurrence and distant metastases.

CONCLUSIONS

We briefly describe and discuss the molecular features and new diagnostic biomarkers for this rare mammary malignancy. The importance of comprehensive profiling is highlighted due to synergistic and potentially antagonistic molecular events in the individual patients.

Histologic heterogeneity of triple negative breast cancer: A National Cancer Centre Database analysis

BACKGROUND

Triple negative breast cancer (TNBC) is an aggressive disease, but recent studies have identified heterogeneity in patient outcomes. However, the utility of histologic subtyping in TNBC has not yet been well-characterised. This study utilises data from the National Cancer Center Database (NCDB) to complete the largest series to date investigating the prognostic importance of histology within TNBC.

METHODS

A total of 729,920 patients (pts) with invasive ductal carcinoma (IDC), metaplastic breast carcinoma (MBC), medullary breast carcinoma (MedBC), adenoid cystic carcinoma (ACC), invasive lobular carcinoma (ILC) or apocrine breast carcinoma (ABC) treated between 2004 and 2012 were identified in the NCDB. Of these, 89,222 pts with TNBC that received surgery were analysed. Kaplan-Meier analysis, log-rank testing and multivariate Cox proportional hazards regression were utilised with overall survival (OS) as the primary outcome.

RESULTS

MBC (74.1%), MedBC (60.6%), ACC (75.7%), ABC (50.1%) and ILC (1.8%) had significantly different proportions of triple negativity when compared to IDC (14.0%, p < 0.001). TNBC predicted an inferior OS in IDC (p < 0.001) and ILC (p < 0.001). Lumpectomy and radiation (RT) were more common in MedBC (51.7%) and ACC (51.5%) and less common in MBC (33.1%) and ILC (25.4%), when compared to IDC (42.5%, p < 0.001). TNBC patients with MBC (HR 1.39, p < 0.001), MedBC (HR 0.42, p < 0.001) and ACC (HR 0.32, p = 0.003) differed significantly in OS when compared to IDC.

CONCLUSION(S)

Our results indicate that histologic heterogeneity in TNBC significantly informs patient outcomes and thus, has the potential to aid in the development of optimum personalised treatments.

Dose invasive apocrine adenocarcinoma has worse prognosis than invasive ductal carcinoma of breast: evidence from SEER database

Background

Invasive apocrine adenocarcinoma (AAC) of breast is a rare histopathological subtype of breast carcinomas. We aim to investigate the different characteristics and prognostic outcomes between AAC and invasive ductal carcinoma (IDC) of breast cancer.

RESULTS

AAC patients presented with older ages, more aggressive behaviors, lower ER and PR proportions, higher HER2 amplification rates and less application of breast-conserving therapy and adjuvant chemotherapy compared to IDC patients. Long-term OS and DSS were both worse in ACC patients (p = 0.006, p = 0.012 respectively) than in IDC patients by Kaplan-Meier analysis. However, no significant difference was detected in DSS (p = 0.181) and OS (p = 0.116) between the matched two histological subtypes. Further subgroup analysis indicated that AJCC stage, ER status, PR status and HER2 status may be principal confounders for AAC prognosis.

Materials and Methods

With accession to the Surveillance, Epidemiology and End Result (SEER) database, a total of 260,596 patients met the eligibility criteria. Clinicopathological characteristics were compared between groups using Chi-square test. Univariate and multivariate analyses were applied to evaluate the overall survival (OS) and disease-specific survival (DSS). Subgroup analyses summarized the hazard ratio (HR) of AAC versus IDC using a forest plot.

Conclusions

AAC had unique clinicopathological characteristics and it tended to be a more aggressive type than IDC. However, the worse prognosis was diminished after matching for demographic and clinicopathological factors. Deeper insights into AAC are in need to contribute to individualized and tailored therapy, which thereby may improve clinical management and outcomes.

The Clinicopathological Features and Survival Outcomes of Different Histological Subtypes in Triple-negative Breast Cancer

Purpose: To determine the clinicopathological features and survival outcomes of triple-negative breast cancer (TNBC) according to different histological subtypes.

Methods: Using the Surveillance, Epidemiology, and End Results database, we included TNBC cases in 2010-2013. The effect of histological subtype on breast cancer-specific survival (BCSS) and overall survival (OS) were analyzed using univariate and multivariate analyses.

Results: A total of 19,900 patients were identified. Infiltrating ductal carcinoma not otherwise specified accounted for 91.6% of patients, followed by metaplastic carcinoma (2.7%), medullary carcinoma (1.4%), mixed lobular-ductal carcinoma (1.4%), lobular carcinoma (1.3%), apocrine carcinoma (1.0%), and adenoid cystic carcinoma (0.6%). Medullary carcinoma was more frequently poorly/undifferentiated. Significantly more lobular carcinoma, mixed lobular-ductal carcinoma, and metaplastic carcinoma patients had larger tumors. Adenoid cystic carcinoma, metaplastic carcinoma, medullary carcinoma, and apocrine carcinoma were more frequently node-negative. Lobular carcinoma (16.0%) and mixed lobular-ductal carcinoma (10.4%) more frequently had distant stage at initial diagnosis. Histologic subtype was an independent prognostic factor of BCSS and OS. Compared with infiltrating ductal carcinoma, medullary carcinoma and apocrine carcinoma had better BCSS and OS, while mixed lobular-ductal carcinoma and metaplastic carcinoma had worse survival. Adenoid cystic carcinoma survival was not significantly different from that of infiltrating ductal carcinoma.

Conclusions: TNBC histological subtypes have different clinicopathological characteristics and survival outcomes. Medullary carcinoma and apocrine adenocarcinoma have excellent prognosis; mixed lobular-ductal carcinoma and metaplastic carcinoma are the most aggressive subtypes.

Triple-negative breast cancer: the importance of molecular and histologic subtyping, and recognition of low-grade variants

Triple-negative breast cancers (TNBCs), defined by lack of expression of estrogen receptor, progesterone receptor and HER2, account for 12–17% of breast cancers and are clinically perceived as a discrete breast cancer subgroup. Nonetheless, TNBC has been shown to constitute a vastly heterogeneous disease encompassing a wide spectrum of entities with marked genetic, transcriptional, histological and clinical differences. Although most TNBCs are high-grade tumors, there are well-characterized low-grade TNBCs that have an indolent clinical course, whose natural history, molecular features and optimal therapy vastly differ from those of high-grade TNBCs. Secretory and adenoid cystic carcinomas are two histologic types of TNBCs underpinned by specific fusion genes; these tumors have an indolent clinical behavior and lack all of the cardinal molecular features of high-grade triple-negative disease. Recent studies of rare entities, including lesions once believed to constitute mere benign breast disease (e.g., microglandular adenosis), have resulted in the identification of potential precursors of TNBC and suggested the existence of a family of low-grade triple-negative lesions that, despite having low-grade morphology and indolent clinical behavior, have been shown to harbor the complex genomic landscape of common forms of TNBC, and may progress to high-grade disease. In this review, we describe the heterogeneity of TNBC and focus on the histologic and molecular features of low-grade forms of TNBC. Germane to addressing the challenges posed by the so-called triple-negative disease is the realization that TNBC is merely a descriptive term, and that low-grade types of TNBC may be driven by distinct sets of genetic alterations.

Cystic apocrine ductal carcinoma in situ with increased EGFR expression, trisomy 7, and associated focal invasion

A 71-year-old woman was admitted to our hospital with a lump in her right breast. Mammography revealed an internal high-density mass in the lower right breast, which was larger than it was 2 years ago. Considering the findings from ultrasonography, computed tomography, and cytology, an intracystic carcinoma could not be ruled out. The patient underwent excisional biopsy, which revealed an apocrine ductal carcinoma in situ (ADCIS) with focal invasive apocrine carcinoma (IAC). The diagnosis was based on morphology and immunohistochemistry (IHC), which was negative for the estrogen and progesterone receptors, and positive for the androgen receptor. Expression of the human epidermal growth factor receptor 2 and the epidermal growth factor receptor (EGFR) received an immunohistochemical score of 2+. Trisomy of chromosome 7, including multiple CEP 7 and EGFR signals, was observed in ADCIS by fluorescence in situ hybridization (FISH). IAC exhibited similar results for IHC and FISH. This is the first reported case showing trisomy 7 resulting in EGFR copy number gain and increased EGFR expression in ADCIS.

Heterogeneity of triple-negative breast cancer: histologic subtyping to inform the outcome

BACKGROUND

This study assesses outcome in terms of disease-free survival (DFS) and overall survival (OS) of special types of triple-negative breast cancer (TNBC).

PATIENTS AND METHODS

We identified 8801 women with first primary nonmetastatic breast cancer operated on at the European Institute of Oncology between 1997 and 2005. Of these patients, 781 consecutive patients with immunohistochemically defined TNBC were selected for the analyses. We explored patterns of recurrence by histologic type. Median follow-up was 5.7 years (range 0-13 years).

RESULTS

The 5-year DFS was 77% for TNBC, 68% for human epidermal growth factor receptor 2 (HER2)-positive breast cancer, and 84% and 95% for luminal B and luminal A breast cancer, respectively. From 781 TNBC subtypes, 693 cases (89%) were classified as ductal not otherwise specified (NOS) (invasive ductal carcinoma [IDC]), 29 were classified as apocrine (3.7%), 18 (2.3%) were classified as lobular, 10 (1.2%) were classified as adenoid cystic, and 10 (1.2%) were classified as metaplastic. Five-year DFS and OS were 77% and 84% for patients with ductal carcinoma, 56% and 89% for patients with metaplastic carcinoma, and both 5-year DFS and OS were 100% for patients with adenoid cystic and medullary carcinomas, respectively.

CONCLUSION

Distinct prognostic implications may derive from the specific histotype of TNBC. The identification of these special types has a significant clinical utility and should be considered in therapeutic algorithms.

Apocrine carcinoma as triple-negative breast cancer: novel definition of apocrine-type carcinoma as estrogen/progesterone receptor-negative and androgen receptor-positive invasive ductal carcinoma

OBJECTIVE

Apocrine carcinoma, a subtype of invasive ductal carcinoma of the breast, expresses androgen receptor (AR), but often lacks estrogen receptor (ER) and progesterone receptor (PgR). In the present study, the author immunohistochemically defined apocrine-type carcinoma as ER-/PgR-/AR+ invasive ductal carcinoma and analyzed the significance of apocrine-type carcinoma as triple-negative breast cancer.

METHODS

Four hundred and forty breast cancers from 429 cases were immunostained for estrogen receptor, progesterone receptor, androgen receptor, human epidermal growth factor receptor type 2 (HER2), p53, Ki-67 and epidermal growth factor receptor. The lesions included 58 in situ malignancies (including 13 apocrine-type lesions) and 325 invasive ductal carcinomas (including 44 apocrine type).

RESULTS

Of 91 estrogen receptor-negative invasive ductal carcinomas, 44 (48%) belonged to apocrine-type carcinoma, and overexpression of human epidermal growth factor receptor type 2 and p53 was observed in 23 (52%) and 33 (75%), respectively. Histologically, 22 (50%) were categorized as classical apocrine carcinoma. Among 281 non-apocrine invasive ductal carcinomas, 30 (11%) were quadruple-negative (ER-/PgR-/AR-/HER2-) and 17 (6%) were hormone receptor-negative and human epidermal growth factor receptor type 2-overexpressed. Invasive ductal carcinomas in the triple-negative breast cancer category (n= 51) were divided into triple-negative, androgen receptor-positive (apocrine, n= 21) and quadruple-negative (non-apocrine, n= 30). p53 overexpression was more often seen in the apocrine-type triple-negative breast cancer (18/21 = 86%) than in the non-apocrine type (14/30 = 46%) (P< 0.05). Ki-67 labeling was significantly higher in the non-apocrine type (58%) than in the apocrine type (37%) (P< 0.01). Epidermal growth factor receptor is consistently expressed in triple-negative breast cancers (16/16 = 100% in apocrine and 18/20 = 90% in non-apocrine).

CONCLUSIONS

Androgen receptor should be added to immunohistochemical panels, since apocrine-type invasive ductal carcinoma, resembling basal-like phenotypes, may show clinical behaviors different from the basal-like triple-negative breast cancer.

The differences in the histological types of breast cancer and the response to neoadjuvant chemotherapy: the relationship between the outcome and the clinicopathological characteristics

Although effective regimens have been established for invasive ductal carcinoma-not otherwise specified (IDC), the efficacy and prognosis of other minor types of breast cancer are unknown because of their rareness. The clinicopathological features and prognosis of other minor types concerning the response to neoadjuvant chemotherapy (NAC) were evaluated in this study. A total of 562 patients were classified according to the Japanese and the World Health Organization (WHO) classifications, and the number of IDC and other special types (SP) was 500 and 62. The SP patients had a significantly poorer clinicopathological response to NAC and less breast-conservative therapy than those with IDC. According to the WHO classification, mucinous carcinoma, metaplastic carcinomas and apocrine carcinoma also responded poorly, and patients with metaplastic carcinomas and invasive lobular carcinoma had a significantly poorer prognosis. Despite the poor response to chemotherapy, patients with mucinous carcinoma and apocrine carcinoma had a good prognosis. The response to NAC and the prognosis vary for each histological type. For some types, the prognosis was not related to the clinicopathological response to NAC.

BACKGROUND

In the treatment of breast cancer, neoadjuvant chemotherapy (NAC) has become the standard treatment modality for downstaging purposes. Although effective regimens have been established for the treatment of invasive ductal carcinoma-not otherwise specified (IDC), the data about the efficacy and prognosis for patients with other minor types of breast cancer are insufficient because of the rareness of these tumors. Defining the relationship between each histological type and the clinicopathological response to NAC is essential to optimizing individualized treatment.

METHODS

We retrospectively evaluated the clinicopathological features and classification of the histological types based on the Japanese and the World Health Organization (WHO) classifications before and after NAC in 562 patients with primary breast cancer who underwent curative treatment after NAC between 1998 and 2008. The prognosis was estimated for each histological type.

RESULTS

Of the 562 patients, the number of cases of IDC and other special types (SP) was 500 and 62. In the SP group, the clinicopathological response to NAC was significantly poorer, and the patients underwent breast-conservative therapy less frequently than did the IDC patients. According to the WHO classification, mucinous carcinoma, metaplastic carcinomas and apocrine carcinoma responded poorly to NAC. The disease-free survival and overall survival were significantly worse for patients with metaplastic carcinomas (p<0.001 and p<0.001) and with invasive lobular carcinoma (p=0.03 and p<0.001) than other cancers. Despite their poor response to treatment, patients with mucinous carcinoma and apocrine carcinoma had a good prognosis.

CONCLUSIONS

The response to standardized NAC and prognosis varies for each histological type. For some types, the prognosis was not associated with the clinicopathological response to NAC. Innovative regimens should therefore be investigated for each histological type to achieve the best response.

Apocrine metaplasia of breast cancer: clinicopathological features and predicting response

BACKGROUND

Tailor-made therapies are currently gaining prominence, and the clarification of predictive markers for anticancer agents represents an important research issue. From our institutional neoadjuvant experience, apocrine carcinoma showed a high correlation with therapeutic effect against breast cancer. We thus considered that apocrine metaplasia (AM) might represent a predictive marker for breast cancer.

METHODS

A total of 210 primary invasive breast cancers from Japanese patients were scored according to the size of cytoplasmic granules and abundance of cytoplasm, then classified into three categories: non-AM, incomplete AM and complete AM. Clinicopathological features were evaluated based on these classifications.

RESULTS

Distribution according to the classification of AM was: non-AM, 61%; incomplete AM, 36%; and complete AM, 3%. No significant differences with regard to estrogen receptor, progesterone receptor, human epidermal growth factor receptor type 2, androgen receptor or bcl-2 were observed among the three groups. Gross cystic fluid protein-15 showed a high positive rate (83%) for complete AM. Cases of incomplete AM and complete AM were combined to form the AM group. Among lymph node-positive patients without chemotherapy, the 10-year recurrence-free survival (RFS) rate was 85% for non-AM and 44% for AM (p < 0.05). Conversely, among the lymph node-positive group with chemotherapy, the 10-year RFS rate was 45% for non-AM and 75% for AM (p < 0.05). Prognoses for non-AM and AM were turned around by chemotherapy. Lymph node metastasis was related to prognosis in multivariate analysis, although AM did not remain an independent prognosticator.

CONCLUSIONS

Apocrine metaplasia appears to offer an effective predictive marker for anticancer therapy.

Invasive apocrine carcinoma of the breast: clinicopathologic features of 57 patients

Apocrine carcinoma is a rare, unique, and morphologically distinctive type of invasive ductal carcinoma (IDC). The features of invasive apocrine carcinoma (IAC) and their possible prognostic implications have not been fully investigated. To this end, we examined the clinicopathologic characteristics and outcome of patients with IAC and compared these factors with those of patients with IDC. Out of 2,055 breast cancer patients who had undergone breast surgery between 1995 and 2005, 57 patients of IAC and 1,583 patients of IDC were analyzed. The mean ages of the patients with IAC and of those with IDC were 58.5 +/- 10.9 years and 54.4 +/- 11 years, respectively (p = 0.006). The percentages of patients with axillary nodal metastasis and lymphatic invasion were significantly lower in the IAC group than in the IDC group (p = 0.03 and 0.02, respectively). The percentage of estrogen and progesterone receptor negativity was higher in the IAC group than in the IDC group (p < 0.001). After a median follow-up period of 49 months (range, 1-133 months), seven (12%) patients with IAC and 244 (15%) patients with IDC had experienced recurrences. Three (5%) patients with IAC and 125 (8%) patients with IDC died of recurrent breast cancer. No significant differences in the relapse-free survival (p = 0.83) and overall survival (p = 0.75) rates were observed between the two groups. Although IAC and IDC have different clinicopathologic characteristics, the prognoses of patients with these diseases are similar.

Expression of androgen receptors and inhibin/activin alpha and betaA subunits in breast apocrine lesions

The importance of androgens and their receptors inhibin and activin remains unknown for mammary epithelial cells. We investigated the role of these hormones in breast apocrine lesions (BAL) using immunohistochemistry to study androgen receptors (AR) and the inhibin/activin alpha and betaA subunits. Forty-two cases of BAL were evaluated, including 22 cases of fibrocystic disease (FCD) showing prominent apocrine changes, 10 intraductal papillomas with extensive apocrine metaplasia, 5 cases of apocrine carcinoma in situ (CIS), and 5 cases of apocrine carcinoma. Fifty non-apocrine lesions were included as controls: 20 cases of FCD, 5 cases of DCIS, and 25 cases of invasive ductal carcinoma. AR was more frequently expressed in BAL than in non-apocrine lesions (p=0.001). AR expression was not related to tumor progression. AR showed a significant positive correlation with betaA subunits (r=0.832, p<0.001), and an inverse correlation with alpha subunits (r=-0.233). The alpha and betaA subunits demonstrated a significant inverse correlation with each other (r=-0.271, p=0.0048). As the expression of the alpha and betaA subunits reflects inhibin and activin A, respectively, AR and activin A may be implicated in apocrine morphogenesis, but not in tumor progression.