Typical medullary carcinoma of the breast: a clinical and pathological analysis of 52 cases

A risk stratification model to predict chemotherapy benefit in medullary carcinoma of the breast: a population-based SEER database

Whether patients with medullary breast carcinoma (MBC) receive chemotherapy is controversial. Therefore, the aim of our study was to screen out patients with MBC who benefit from chemotherapy. We enrolled 618 consecutive patients with MBC from The Surveillance, Epidemiology, and End Results (SEER) database (2010-2018). Cox regression analysis was used to identify independent prognostic factors. Next, a nomogram was constructed and evaluated using calibration plots and the area under the curve (AUC) of receiver operating characteristic (ROC) curves. Kaplan‒Meier curves were used to evaluate the overall survival (OS) benefit of chemotherapy in different risk groups. A total of 618 MBC patients were involved in our study, and an 8:2 ratio was used to randomly split them into a training cohort (n = 545) and a validation cohort (n = 136). Next, a nomogram predicting 3- and 5-year OS rates was constructed based on the five independent factors (age at diagnosis, T stage, N status, subtype and radiation). The nomogram AUCs for 3- and 5-year OS (training set: 0.793 and 0.797; validation set: 0.781 and 0.823) and calibration plots exhibited good discriminative and predictive ability. Additionally, a novel risk classification system for MBC patients demonstrated that we do not have enough evidence to support the benefit effect of chemotherapy for the high-risk group as the result is not statistically significant (total population: p = 0.180; training set: p = 0.340) but could improve OS in the low-risk group (total population: p = 0.001; training set: p = 0.001). Our results suggested that chemotherapy should be selected more carefully for high-risk groups based on a combination of factors and that the possibility of exemption from chemotherapy should be confirmed by more clinical trials in the future.

Competing Risk Analyses of Medullary Carcinoma of Breast in Comparison to Infiltrating Ductal Carcinoma

The aim of current study was to use competing risk model to assess whether medullary carcinoma of the breast (MCB) has a better prognosis than invasive ductal carcinomas of breast cancer (IDC), and to build a competing risk nomogram for predicting the risk of death of MCB. We involved 3,580 MCB patients and 319,566 IDC patients from Surveillance, Epidemiology, and End Results (SEER) database. IDC was found to have a worse BCSS than MCB (Hazard ratio (HR) > 1, p < 0.001). The 5-year cumulative incidences of death (CID) was higher in IDC than MCB (p < 0.001). Larger tumor size, increasing number of positive lymph nodes and unmarried status were found to worsen the BCSS of MCB (HR > 1, p < 0.001). We found no association between ER, PR, radiotherapy or chemotherapy and MCB prognosis (p > 0.05). After a penalized variable selection process, the SH model-based nomogram showed moderate accuracy of prediction by internal validation of discrimination and calibration with 1,000 bootstraps. In summary, MCB patients had a better prognosis than IDC patients. Interestingly, unmarried status in addition to expected risk factors such as larger tumor size and increasing number of positive lymph nodes were found to worsen the BCSS of MCB. We also established a competing risk nomogram as an easy-to-use tool for prognostic estimation of MCB patients.

Breast Carcinoma: Updates in Molecular Profiling 2018

The most significant contribution of molecular subtyping of breast carcinomas has been the identification of estrogen-positive and estrogen-negative tumor subtypes. Knowledge of genetic alterations in these tumors will help clinicians identify novel therapeutic targets. Understanding the progression pathways involved in the transition of in situ carcinoma to invasive carcinoma might lead to efficient risk stratification in these patients. The Cancer Genome Analysis Network has collected genomic and epigenomic data to provide comprehensive information regarding carcinogenesis and pathway interactions. Such information improves understanding of the disease process and also provides more accurate information toward identifying targetable mutations for treatment.

Diagnostic significance of intratumoral CD8+ tumor-infiltrating lymphocytes in medullary carcinoma

Invasive ductal carcinomas of breast with marked stromal lymphocytic infiltration have come to be classified as lymphocyte-predominant breast cancer (LPBC) because it obtains high pathological complete response rates with neoadjuvant chemotherapy. Medullary carcinoma (MC), which is independent from LPBC, is a rare histological subtype of invasive breast carcinoma accompanied by abundant lymphoplasmacytic infiltration as LPBC. Although MC shows marked cellular and structural atypia, it usually has a favorable outcome. It is occasionally difficult to distinguish MC from LPBC because both subtypes have nonspecific morphological features according to the present diagnostic criteria. Herein, we adopted multiplexed fluorescent immunohistochemistry to perform quantitative and simultaneous analyses of tumor-infiltrating lymphocytes (TILs) considering their spatial distribution and examined focal immune reaction differences between MC and LPBC. We found that CD8+ TILs are predominant in the intratumoral region, whereas CD4+ TILs are less common in MC. In non-luminal-type cancers, the numbers of stromal and intratumoral CD8+ TILs were significantly higher in MC than in LPBC. Stratified analyses by CD4+ TIL subsets showed robust infiltration of intratumoral CD8+ TILs in non-luminal-type MC even in suppressive environments, such a low T helper 1-to-regulatory T cell ratio. Our results suggest that extensive intratumoral CD8+ TIL infiltration might well be a promising biomarker for distinguishing MC from LPBC, especially in non-luminal-type cancers. Intratumoral CD8+ TILs and nonluminal intrinsic subtypes may serve as diagnostic characteristics allowing reliable histological criteria to be established for reproducibly diagnosing MC.

Clinicopathologic characteristics of typical medullary breast carcinoma: a retrospective study of 117 cases

PURPOSE

This study analyzed the clinicopathologic characteristics of typical medullary breast carcinoma (TMBC) in a cohort of Chinese patients.

METHODS

We conducted a retrospective review of clinical data including general information, pathologic results, treatment regimens, and patient survival in cases of TMBC diagnosed between February 2004 and April 2011.

RESULTS

A total of 117 patients were enrolled, with a median age of 52 years (range, 28∼92 years). Stage I and II disease accounted for 31.6% and 61.6% of the cases, respectively. Hormonal receptor negative disease (estrogen receptor negative, 68.4%; progestogen receptor negative, 86.3%) was more prevalent in this population. Human epidermal growth factor receptor-2 (HER-2) positivity was 20.5%, while equivocal and HER-2 negative cases represented 16.2% and 63.2% of the cohort. The triple-negative, luminal, and HER-2 overexpressing subtypes constituted 44.4%, 31.6%, and 15.4% of the cases, respectively. The various TMBC subtypes showed no differences regarding tumor size, rates of lymph node(s) metastasis, TNM staging, treatment regimens, and 2-year recurrence rates. However, patients with triple-negative disease were more likely to be younger, when compared to those with luminal disease (P = 0.002). At a median follow-up of 56 months (range, 2-112 months), the 2-year disease-free survival and overall survival rates were 99.1% and 98.2%, respectively.

CONCLUSION

Early stage disease dominated the study cohort, and at two years after surgery, recurrence was extremely low. The heterogeneity of molecular subtypes was clearly shown, and no apparent differences were found among the clinicopathologic characteristics of the triple-negative, luminal, and HER-2 overexpressing subtypes.

Breast carcinoma: molecular profiling and updates

The most significant contribution of molecular subtyping of breast carcinomas has been the identification of estrogen-positive and estrogen-negative tumor subtypes, which are 2 distinct entities with differing prognoses and requiring different therapy. Molecular and genetic analyses can provide prognostic information; however, a thorough histopathologic evaluation with an evaluation of predictive biomarkers will provide similar information. Knowledge of genetic alterations in these tumors will help identify novel therapeutic targets, which might have an impact on prognosis. Understanding the progression pathways involved in the transition of in situ carcinoma to invasive carcinoma might lead to efficient risk stratification in these patients.

Comparison of the characteristics of medullary breast carcinoma and invasive ductal carcinoma

PURPOSE

Medullary breast carcinomas (MBC) have been known to represent a rare breast cancer subtype associated with a more favorable prognosis than invasive ductal carcinomas (IDC). The purpose of this study was to compare the clinicopathologic characteristics and outcomes of MBC with those of IDC.

METHODS

We retrospectively reviewed medical records of patients with invasive breast cancer who were managed surgically from August 1995 to June 2010.

RESULTS

Fifty-two patients were identified with MBC and 5,716 patients were identified with IDC. The clinicopathologic features, disease-free survival (DFS), and overall survival (OS) of patients with MBC were compared with those of patients with IDC. The MBC group presented at a younger age (p=0.005) and had a significant association with a higher histological grade (p=0.003) and nuclear grade (p<0.001) as well as negative estrogen receptor (p<0.001) and progesterone receptor (p<0.001) status. Lymphatic invasion was absent (p<0.001) and lymph node metastasis was rare (p<0.001). The DFS and OS did not differ significantly between the two groups (5-year DFS: 88.0% vs. 89.2%, p=0.920; 5-year OS: 93.4% vs. 94.4%, p=0.503). In multivariate analysis, the factors associated with DFS and OS were nuclear grade, histological grade, tumor size, lymph node metastasis, estrogen receptor status, progesterone receptor status, and human epidermal growth factor receptor 2 status, chemotherapy, and hormone therapy. However, DFS and OS were not significantly different between IDC and MBC according to histological type itself (DFS: hazard ratio 0.85, 95% confidence interval 0.12-6.05, p=0.866; OS: hazard ratio 1.49, 95% confidence interval 0.21-10.77, p=0.692).

CONCLUSION

Although MBC has specific clinicopathologic features, its prognosis does not differ from IDC and is determined by prognostic factors such as tumor size and lymph node metastasis. Therefore, patients with MBC also require the same intensive treatment provided for IDC.

Clinicopathologic characteristics at diagnosis and the survival of patients with medullary breast carcinoma in China: a comparison with infiltrating ductal carcinoma-not otherwise specified

BACKGROUND

Few studies have addressed the biological features of medullary breast carcinoma (MBC) in the context of clinical outcomes. We sought to compare the baseline demographics, standard pathologic factors and long-term clinical outcomes between MBC and infiltrating ductal carcinoma-not otherwise specified (IDC-NOS) using a large database.

METHODS

A total of 2,202 cases with pure IDC-NOS and 188 cases with typical MBC meeting the inclusion criteria were identified. The clinical and biological features, the overall survival (OS) and recurrence/metastasis-free survival (RFS) were compared for both groups.

RESULTS

There were a higher proportion of patients diagnosed prior to 40 years of age in the MBC group compared to the IDC-NOS group. MBC cases demonstrated less aggressive tumor features such as lower tumor stage, smaller tumor size and a lower proportion of nodal involvement than IDC-NOS; however, immunohistochemical staining revealed that MBC displayed the triple-negative phenotype more often than IDC-NOS cases (40.4% versus 26.2%; P <0.001). Although the clinical behavior of MBC was not commensurate with its pathologic features, women diagnosed with MBC had a lower frequency of recurrence/metastasis (P = 0.032) and death (P = 0.042) than those with IDC-NOS, and the 10-year OS and RFS were significantly higher for MBC (91% and 74%) compared to IDC-NOS (81% and 64%). Moreover, multivariate analysis revealed that TNM stage was a statistically significant factor for survival.

CONCLUSIONS

MBC in Chinese women demonstrated less aggressive behavior and better prognosis than IDC-NOS. This favorable outcome was maintained after 10 years.

Prognosis of medullary breast cancer: analysis of 13 International Breast Cancer Study Group (IBCSG) trials

BACKGROUND

To evaluate whether medullary breast cancer has a better prognosis compared with invasive ductal tumors.

METHODS

Among 12,409 patients, 127 were recorded as invasive medullary tumors and 8096 invasive ductal tumors. Medullary and ductal invasive tumors were compared with regard to stage, age at diagnosis, grade, hormone receptor status, peritumoral vascular invasion, and local and systemic treatment. Pattern of relapse, distant recurrence-free interval (DRFI), and overall survival (OS) were determined for both histological groups. Two cohorts were investigated: a full cohort including the pathologist-determined medullary histology without regard to any other tumor features and a cohort restricted to patients with ER-negative grade 3 tumors.

RESULTS

Fourteen-year DRFI and OS percents for medullary tumors (n = 127) and invasive ductal tumors (n = 8096) of the full cohort were 76% and 64% [hazard ratio (HR) 0.52, P = 0.0005] and 66% and 57% (HR = 0.75, P = 0.03), respectively. For the restricted cohort, 14-year DRFI and OS percents for the medullary (n = 47) and invasive ductal tumors (n = 1407) were 89% and 63% (HR 0.24, P = 0.002) and 74% and 54% (HR = 0.55, P = 0.01), respectively. Competing risk analysis for DRFI favored medullary tumors (HR medullary/ductal = 0.32; 95% confidence interval = 0.13-0.78, P = 0.01).

CONCLUSION

Medullary tumors have a favorable prognosis compared with invasive ductal tumors.

In breast cancer, a high ratio of tumour-infiltrating intraepithelial CD8+ to FoxP3+ cells is characteristic for the medullary subtype

AIMS

Medullary breast cancer (MBC) is a biologically distinct subtype of breast cancer characterized by prominent lymphocytic infiltrates and a favourable clinical outcome. Tumour-infiltrating CD8+ effector T cells may contribute to the good prognosis of this type of cancer; however, certain subtypes of lymphocyte, such as FoxP3+ regulatory T cells (Tregs), can also suppress antitumour immunity.

METHODS AND RESULTS

We determined tumour infiltration by FoxP3+, CCL22+ and CD8+ cells in paraffin-embedded sections of MBC, and, as a reference, in samples of grade 3 ductal, lobular and mucinous breast cancer. All analysed MBCs were strongly infiltrated by FoxP3+ cells, whereas only weak infiltrates were detected in ductal or lobular breast cancer. This finding was unexpected, given the good prognosis of MBC. Strikingly, the number of CD8+ T cells exceeded the number of FoxP3+ cells in MBC (ratio of CD8+ to FoxP3+ cells of 2.6), whereas equal amounts of both cell types were found in ductal breast cancer (ratio of CD8+ to FoxP3+ cells of 1.1). In both types of breast cancer, we also detected cells expressing the Treg-attracting chemokine CCL22.

CONCLUSIONS

In breast cancer, a predominance of tumour-infiltrating CD8+ over FoxP3+ cells was observed in MBC. Thus, the ratio of CD8+ to FoxP3+ cells rather than the absolute number of intratumoral FoxP3+ cells may be predictive for the clinical outcome of cancer.

Medullary carcinoma of the breast: a population-based perspective

Prognostic factors specific to medullary carcinoma of the breast (MCB) are unknown. Our objective was to identify patient and tumor factors predictive of overall survival (OS) in a large cohort of MCB patients. The Surveillance, Epidemiology, and End Results database was used to identify patients with MCB diagnosed from 1988 to 2004. Patient, tumor, and treatment factors were compared by univariate analysis via the Kaplan–Meier method and survival differences detected using the log-rank test. A multivariate Cox proportional hazards model controlled for patient age, race, type of surgery, radiotherapy, tumor size, number of lymph node metastases (LNM), lymph node yield (LNY), estrogen receptor (ER) and progesterone receptor (PR) status, and extent of disease. On univariate analysis of 3,348 patients, factors influencing OS included age, race, tumor size, ER status, type of surgery, radiotherapy, LNM, LNY, and extent of disease (P<0.001). On multivariate analysis, advancing age (P<0.001), black race (P<0.001), regional metastases (P<0.001), distant metastases (P<0.001), increasing tumor size (P<0.001), ER positivity (P=0.003), and increasing LNM (P<0.001) were associated with decreased OS. An OS benefit was seen in PR-positive patients (P=0.002) and in those with increasing LNY (P<0.001). Even among node-negative patients, increasing LNY was associated with improved OS (P<0.001). Tumor size, LNM, regional and distant metastases, PR status, age, and race are important prognostic factors in MCB. ER positivity was associated with decreased OS, which may reflect inaccuracy in diagnosing MCB or a significant biologic variant. The improved OS seen with increasing LNY in node-negative patients suggests MCB may be currently understaged.

Distinguishing medullary carcinoma of the breast from high-grade hormone receptor-negative invasive ductal carcinoma: an immunohistochemical approach

AIMS

Medullary carcinomas (MCs) represent a rare breast cancer subtype associated with a rather favourable prognosis compared with invasive ductal carcinomas (IDCs). Due to histopathological overlap, MCs are frequently misclassified as high-grade IDCs, potentially leading to overtreatment of MCs. Our aim was to establish novel diagnostic markers distinguishing MCs from hormone receptor-negative high-grade IDCs.

METHODS AND RESULTS

Sixty-one MCs and 133 hormone receptor-negative IDCs were analysed in a comparative immunohistochemical study. Applied markers included a comprehensive panel of cytokeratins (CKs), vimentin, smooth muscle actin (SMA), p63, p53, cell adhesion molecules [N-CAM (CD56), syndecan-1 (CD138), E-cadherin and P-cadherin] and development associated transcription factors (AP-2 alpha, AP-2 gamma). A significantly higher proportion of IDCs displayed increased expression of CK7, AP-2 alpha and HER2 in contrast to MCs (CK7: 91% of IDCs versus 77% of MCs; AP-2 alpha: 77% versus 57%; and HER2: 26% versus 7%, each P < 0.01). Vice versa, MCs were slightly more frequently positive for SMA and vimentin (P > 0.05).

CONCLUSIONS

Hormone receptor-negative high-grade IDCs are significantly associated with luminal differentiation, Her2 and AP-2 alpha overexpression, whereas MCs tend to display myoepithelial features. Markers analysed in this study are of diagnostic value regarding the differential diagnosis of MCs.

Medullary carcinoma of the breast: Role of contrast-enhanced MRI in the diagnosis of multiple breast lesions

Medullary carcinoma is a rare breast carcinoma with a syncytial growth pattern and high-grade cytology. It can be difficult to diagnose and may be missed on conventional imaging as the findings may overlap with benign lesions i.e. fibroadenomas. The authors report a case of a 25-year-old female who presented with multifocal breast lumps diagnosed with medullary carcinoma and fibroadenomas. Imaging and pathological correlation with contrast-enhanced MRI are presented in the diagnosis of these lesions.

Rare (new) entities of the breast and medullary carcinoma

Rare tumours are a heterogeneous group of conditions that encompass benign to malignant lesions both of stromal and epithelial origin. Here some of these tumours are described, in which the authors have most familiarity. An outline of medullary carcinoma is also presented.

MR imaging of medullary carcinoma of the breast

PURPOSE

To examine the magnetic resonance imaging (MRI) findings of medullary carcinoma of the breast and to correlate them with histopathologic features.

MATERIALS AND METHODS

Eight patients were retrospectively evaluated with pathologically confirmed medullary carcinoma of the breast. T1-weighted fat-saturated, T2-weighted fast spine echo, and gadolinium-enhanced fat-saturated fast spoiled gradient-echo images were obtained. Interpretation of the MRI findings was based on evaluation of the configuration, internal signal intensity, contrast enhancement, and type of the time-intensity curve.

RESULTS

Medullary carcinoma showed a lobular shape and a smooth margin, either homogenous or heterogeneous enhancement and delayed peripheral enhancement in the late phase on contrast-enhanced MRI, and either a plateau or washout type with rapid initial rise on the time-intensity curve of the dynamic study.

CONCLUSION

Although the MRI findings showed a close relationship with histopathologic features of medullary carcinoma, it was difficult to differentiate medullary carcinoma from other histologic types of invasive breast carcinomas.

A locally advanced breast cancer with difficult differential diagnosis of carcinosarcoma and atypical medullary carcinoma, which had poor response to adriamycin- and taxane-based neoadjuvant chemotherapy: a case report

Atypical medullary carcinomas and carcinosarcoma have unique histopathological features. Here we present a case with a breast malignancy that had pathological characteristics of both. A 54-year old patient with a malignant breast mass received 6 cycles of adriamycin-based chemotherapy, followed by 3 cycles of paclitaxel monotherapy, and had a poor clinical response to treatment. A modified radical mastectomy was performed. The pathological diagnosis was complicated by an inability to distinguish between atypical medullary carcinoma and carcinosarcoma. The findings included a tumor that was well-circumscribed, high grade and a syncytial growth pattern as well as biphasic sarcomatous and carcinomatous characteristics. In conclusion, atypical medullary carcinoma and carcinosarcoma of the breast have entirely different prognoses and should be managed differently. Both should be treated by surgical resection, and additional therapy should be considered based on the cancer with the poorer prognosis.

Diagnostik und Immunhistochemie des medullären Mammakarzinoms

Medullary carcinoma of the breast has a relatively favorable prognosis despite its malignant histopathological appearance, providing a challenge for the pathologically based diagnosis of breast cancer. Macroscopic and microscopic findings combined provide diagnostic criteria. The importance of the immunophenotype of medullary carcinoma is not well defined. Because the reproducibility of morphological criteria is limited, we conducted an immunohistochemical study in search of markers that could facilitate histopathological classification. We examined 32 medullary carcinomas in comparison with 30 high grade ductal invasive carcinomas with similar morphology using 23 different immunohistochemical markers. The results showed an overlap with the so called basal like subtype of invasive breast cancer (negativity for steroid hormone receptor, positivity for basal cytokeratins). None of the immunohistochemical markers enabled a specific discrimination between the two groups. Medullary carcinomas overexpress EGF-R more frequently (P<0.004). In combining the characteristic morphological criteria and the immunohistochemical detection of the basal like phenotype and EGFR, a higher diagnostic accuracy can be achieved. The immunophenotype alone does not allow a definite classification of medullary carcinoma.

Clinicopathologic features and long-term outcome of patients with medullary breast carcinoma managed with breast-conserving therapy (BCT)

PURPOSE

The purpose of this study is to compare the clinical characteristics and outcome of medullary carcinoma to infiltrating ductal carcinoma of the breast in a large cohort of conservatively managed patients with long-term follow-up.

METHODS AND MATERIALS

Chart records of patients with invasive breast cancer managed with breast-conserving therapy (BCT) at the therapeutic radiology facilities of Yale University School of Medicine before 2001 were reviewed. Forty-six cases (1971-2001) were identified with medullary histology; 1,444 patients with infiltrating ductal carcinoma served as a control group.

RESULTS

The medullary cohort presented at a younger age with a higher percentage of patients in the 35 years or younger age group (26.1% vs. 6.6%, p < 0.00001). Twelve patients with medullary histology underwent genetic screening, and 6 patients were identified with deleterious mutations. This group showed greater association with BRCA1/2 mutations compared with screened patients in the control group (50.0% vs. 15.8%, p = 0.0035). The medullary cohort was also significantly associated with greater T stage and tumor size (37.0% vs. 17.2% T2, mean size 3.2 vs. 2.5 cm, p = 0.00097) as well as negative ER (84.9% vs. 37.6%, p < 0.00001) and PR (87.5% vs. 48.1%, p = 0.00001) status. As of February 2003, median follow-up times for the medullary and control groups were 13.9 and 14.0 years, respectively. Although breast relapse-free rates were not significantly different (76.7% vs. 85.2%), 10-year distant relapse-free survival in the medullary cohort was significantly better than in the control group (94.9% vs. 77.5%, p = 0.028).

CONCLUSIONS

Despite poor clinicopathologic features, patients with medullary histology demonstrate favorable long-term distant relapse-free survival. Local control rates of patients with medullary and infiltrating ductal carcinoma are comparable. These findings suggest that patients diagnosed with medullary carcinoma are appropriate candidates for BCT and are associated with favorable long-term prognosis.

Prognostic relevance of gene amplifications and coamplifications in breast cancer

Multiple different oncogenes have been described previously to be amplified in breast cancer including HER2, EGFR, MYC, CCND1, and MDM2. Gene amplification results in oncogene overexpression but may also serve as an indicator of genomic instability. As such, presence of one or several gene amplifications may have prognostic significance. To assess the prognostic importance of amplifications and coamplifications of HER2, EGFR, MYC, CCND1, and MDM2 in breast cancer, we analyzed a breast cancer tissue microarray containing samples from 2197 cancers with follow-up information. Fluorescence in situ hybridizations revealed amplifications of CCND1 in 20.1%, HER2 in 17.3%, MDM2 in 5.7%, MYC in 5.3%, and EGFR in 0.8% of the tumors. All gene amplifications were significantly associated with high grade. HER2 (P < 0.001) and MYC amplification (P < 0.001) were also linked to shortened survival. In case of HER2, this was independent of grade, pT, and pN categories. MYC amplification was almost 3 times more frequent in medullary cancer (15.9%), than in the histologic subtype with the second highest frequency (ductal; 5.6%; P = 0.0046). HER2 and MYC amplification were associated with estrogen receptor/progesterone receptor negativity (P < 0.001) whereas CCND1 amplification was linked to estrogen receptor/progesterone receptor positivity (P < 0.001). Coamplifications were more prevalent than expected based on the individual frequencies. Coamplifications of one or several other oncogenes occurred in 29.6% of CCND1, 43% of HER2, 55.7% of MDM2, 65% of MYC, and 72.8% of EGFR-amplified cancers. HER2/MYC-coamplified cancers had a worse prognosis than tumors with only one of these amplifications. Furthermore, a gradual decrease of survival was observed with increasing number of amplifications. In conclusion, these data support a major prognostic impact of genomic instability as determined by a broad gene amplification survey in breast cancer.

Immunophenotype of lymphocytic infiltration in medullary carcinoma of the breast

Medullary carcinoma (MC) of the breast is characterized by large anaplastic cells and infiltration by benign lymphocytes. Patients with this pattern of breast carcinoma are considered to have a better prognosis than those with other histological subtypes. We reviewed cases of primary breast carcinoma that were surgically resected between 1990 and 2004. Of these, 13 cases of medullary carcinoma of the breast with lymphocyte infiltration were reported. Tests for CD3, CD4, CD8, CD20, CD56, TIA-1, and granzyme B were performed on paraffin sections. We found that the MC contained very few NK cells, as assessed by their reactivity with the CD56 antibodies. However, MC had a significantly greater percentage of CD3, CD8, TIA-1, and granzyme B lymphocytes infiltrating the stroma of the tumor. Furthermore, more CD8-positive than CD4-positive T-cell lymphocytes were present within the tumor cell nests in MC, as opposed to the proportion in usual ductal carcinoma. The infiltrating cytotoxic/suppressor T cells in MC represent host resistance against cancer, and the high grading of the T-cell infiltration could explain, in part, a key mechanism controlling the good prognosis for this type of tumor and solve the pathological paradox of MC.

Prognostic value of morphology and hormone receptor status in breast cancer - a population-based study

We analysed the 5-year relative survival among 4473 breast cancer cases diagnosed in 1990–1992 from cancer registries in Estonia, France, Italy, Spain, the Netherlands and the UK. Among eight categories based on ICD-O codes (infiltrating ductal carcinoma, lobular plus mixed carcinoma, comedocarcinoma, ‘special types’, medullary carcinoma, not otherwise specified (NOS) carcinoma, other carcinoma and cancer without microscopic confirmation), the 5-year relative survival ranged from 66% (95% CI 61–71) for NOS carcinoma to 95% (95% CI 90–100) for special types (tubular, apocrine, cribriform, papillary, mucinous and signet ring cell); 27% (95% CI 18–36) for cases without microscopic confirmation. Differences in 5-year relative survival by tumor morphology and hormone receptor status were modelled using a multiple regression approach based on generalised linear models. Morphology and hormone receptor status were confirmed as significant survival predictors in this population-based study, even after adjusting for age and stage at diagnosis.

Medullary carcinoma, provocative now as then

The recent observation that studies of BRCA1-associated tumors contain a high proportion of medullary carcinomas and ductal carcinomas with medullary features has re-introduced pathologists to an old diagnostic problem. The term "medullary carcinoma" dates to the 19th century, but the modern entity was introduced in 1949 by Moore and Foote, who described a carcinoma with a lymphoid infiltrate, a favorable prognosis, and low frequency of metastasis. Almost three decades later, Ridolfi et al proposed specific criteria for diagnosis, resulting in an entity with an even more favorable prognosis and a lower incidence. The reproducibility and clinical relevance of the diagnosis have been questioned recently, and new criteria have been proposed and compared. The tumors typically express cytokeratin 7, often vimentin and S100-protein, but not cytokeratin 20. The usual ones are positive for p53 and negative for estrogen receptor, Her2/neu, and bcl-2. Medullary carcinomas express e-cadherin and beta-catenin more often than ordinary high-grade ductal carcinomas, and the former have genetic differences from the latter. The lymphoid infiltrate of medullary carcinomas is related to beta-actin fragments exposed by apoptotic cells. The present review discusses historical and recent developments and emphasizes diagnostic criteria.

Frequency of sentinel lymph node metastases in patients with favorable breast cancer histologic subtypes

BACKGROUND

The need for axillary nodal staging in favorable histologic subtypes of breast cancer is controversial.

METHODS

Patients with clinical stage T1-2, N0 breast cancer were enrolled in a prospective, multi-institutional study. All patients underwent sentinel lymph node (SLN) biopsy followed by completion level I/II axillary dissection.

RESULTS

SLN were identified in 3,106 of 3,324 patients (93%). Axillary metastases were found in 35% and 40% of patients with infiltrating ductal carcinoma and infiltrating lobular carcinoma, respectively. Among tumor subtypes, positive nodes were found in 17% of patients with pure tubular carcinoma, 7% of patients with papillary cancer, 6% of patients with colloid (mucinous) carcinoma, 21% of patients with medullary carcinoma, and 8% of patients with DCIS with microinvasion.

CONCLUSIONS

Patients with favorable breast cancer subtypes have a significant rate of axillary nodal metastasis. Axillary nodal staging remains important in such patients; SLN biopsy is an ideal method to obtain this staging information.

Translocation of an intracellular antigen to the surface of medullary breast cancer cells early in apoptosis allows for an antigen-driven antibody response elicited by tumor-infiltrating B cells

Tumor-infiltrating lymphoplasmacytic cells are a key feature of medullary carcinoma of the breast (MCB), a distinct subtype of human breast cancer that, despite cytologically anaplastic characteristics, has a more favorable prognosis than other types of breast cancer. Since it has been proposed that the improved clinical outcome is due at least in part to the presence of a prominent lymphoplasmacytic cell infiltrate in the tumor stroma, we recently examined the tumor-infiltrating B cell response in MCB and showed that it is oligoclonal and directed against an intracellular protein translocated to the cell surface upon MCB cell apoptosis. Human Abs cloned from MCB lymphoplasmacytic infiltrate-derived phage display libraries and reflecting the dominant part of the response were used to identify the target Ag as actin. Here, we have characterized in detail the cloned human IgG Abs and the translocation process of actin to the cell surface of apoptotic MCB cells. Our analysis shows that the cloned Abs bind specifically and with high affinity to actin, as determined by ELISA and surface plasmon resonance. Sequence analysis revealed that the Abs are highly somatically mutated, with high replacement to silent ratios, indicative of an Ag-driven, affinity-matured response. Interestingly, the tumor-infiltrating B cells in half the MCB patients mainly exhibited an IgG2 response, while IgG1 dominated in the others. To gain insight to the molecular events that may elicit such an Ab response, we examined the translocation of actin to the cell surface of apoptotic MCB cells using flow cytometry and laser scanning cytometry. Our results show that actin becomes exposed on the cell surface of a large proportion of apoptotic MCB cells as an early apoptotic event. We propose that the Ab response against actin produced by tumor-infiltrating B lymphoplasmacytic cells is Ag-driven, affinity-matured, and elicited due to the increased rate of apoptosis occurring within the MCB tumor that facilitates the translocation and proteolytic fragmentation of intracellular proteins.

Sonographic and pathologic findings in typical and atypical medullary carcinomas of the breast

PURPOSE

We investigated whether there was a relationship between the sonographic and histologic appearances of medullary carcinomas of the breast to determine whether sonography is helpful in the differentiation of typical and atypical medullary carcinomas.

METHODS

We retrospectively reviewed the histologic slides and sonograms of 20 patients who had been diagnosed with medullary carcinoma of the breast. We then classified the carcinomas as typical or atypical based on strict histologic criteria. We also evaluated the relationship between sonographic findings and the histologic reclassification.

RESULTS

Eight (40%) of the 20 medullary carcinomas were classified as typical, and 12 (60%) were classified as atypical. On sonography, a smooth outline was visualized in 6 (75%) of the 8 typical medullary carcinomas but in none of the 12 atypical carcinomas. A jagged margin was sonographically visualized in 10 (83%) of the 12 atypical carcinomas, and a focal irregularity in the margin was visualized in 2 (17%) of the 12 atypical carcinomas. Four of the typical medullary carcinomas had posterior enhancement, and 9 of the atypical medullary carcinomas showed retrotumoral shadowing. The difference in tumor-margin regularity between typical and atypical medullary carcinomas was found to be statistically significant (p < 0.001) using the 2-tailed Fisher's exact test.

CONCLUSIONS

To prevent overdiagnosis of medullary carcinoma, a thorough pathologic review of the entire tumor is recommended if sonography shows a jagged margin or a margin with focal irregularity.

BRCA1 expression levels predict distant metastasis of sporadic breast cancers

The role of BRCA1 in progression of sporadic breast cancers has to date been equivocal, although preliminary studies on small numbers of samples have suggested an association between expression levels of this gene and acquisition of an invasive phenotype. We have further reasoned that loss of oestrogen receptor positivity may have a detrimental effect on BRCA1 expression. In order to test this hypothesis and extend earlier investigations we have applied a sensitive RT-PCR procedure to determine the associations between BRCA1 expression and a variety of clinical parameters in a sample cohort derived from sporadic breast tumour specimens. We have established that BRCA1 and ER mRNA expression are closely associated (p=0.013), indicating a possible functional relationship between these 2 genes. We have further identified an association between low levels of BRCA1 expression and acquisition of distant metastasis in sporadic disease (p=0.019). In light of our findings, we suggest that suppression of BRCA1 has a role to play in progression of a significant fraction of sporadic breast cancers and may additionally prove to be a useful, novel, prognostic marker for this disease type.