Medullary carcinoma, provocative now as then

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.

Rare Breast Cancer Subtypes

PURPOSE OF REVIEW

Breast cancer is a collection of diseases including the more common invasive ductal and lobular carcinomas and rarer subtypes of breast cancer. This review summarizes the features of rare breast cancers.

RECENT FINDINGS

Each of the rare tumors has defined pathological and clinical features that impact treatment recommendations. In this review, we summarize these for each rare type of breast cancer and where available we include molecular features of each tumor. Rare subtypes of breast cancer each have unique features. In many cases, data is limited for the optimal treatment approaches.

Fifty years of thyroid pathology: concepts and developments

The past half century has seen a number of advances in pathology of thyroid diseases, especially neoplastic lesions. These include the description of new entities, the definition of prognostically important lesions, the incorporation of fine needle aspiration biopsy and its functional risk stratification of diagnoses into the clinical evaluation and therapeutic recommendations of the patient with thyroid nodules and the understanding of thyroid neoplastic development, diagnostic and prognostic parameters by use of molecular analysis so that such techniques are becoming standard of care for patients with thyroid tumors. The histopathologist and cytopathologist have been and continue to be at the forefront in the definition and understanding of these areas of thyroid disease. This review describes many of the most important advances in this area in an attempt bring the practicing pathologist up to date in these developments.

A CLDN1-negative phenotype predicts poor prognosis in triple-negative breast cancer

Introduction

Triple-negative breast cancer (TNBC) is a heterogeneous disease with no definitive prognostic markers. As a major component of tight junctions, claudins (CLDNs) presumably play an important role in carcinogenesis and progression of breast cancer. This study was aimed at determining the relationship between the expression of CLDNs and the clinical outcomes of TNBCs.

Materials and Methods

The surgical specimens of primary breast tumors from a consecutive cohort of 173 TNBC patients were retrospectively collected. The membranous expression of CLDN1, CLDN2, CLDN4, and CLDN7 was measured by immunohistochemistry. Then, the associations between CLDN expression, clinicopathological features, and clinical outcomes were assessed.

Results

Positive CLDN1, CLDN2, CLDN4, and CLDN7 membrane expression was detected in 44.5%, 54.9%, 76.9%, and 73.4% of the cohort specimens, respectively. A lack of CLDN1 expression was related to only lymph node metastasis (P = 0.014). The rate of CLDN4-positive tumors was significantly increased in tumors of a higher grade (P = 0.003). Importantly, negative CLDN1 expression was associated with worse relapse-free survival (RFS) in both lymph node positive (LN+) and negative (LN−) cases (both P<0.001). Similarly it was also associated with shorter overall survival (OS)(P = 0.003 in LN+ cases; P = 0.018 in LN− cases). In the LN+ subgroup, CLDN2-negative cases had a significantly higher risk of recurrence (P = 0.008). Multivariate analysis revealed that negative CLDN1 expression was an independent prognostic factor for high risk of both recurrence and death (HR 5.529, 95% CI 2.664–11.475, P<0.001; HR 3.459, 95% CI 1.555–7.696, P = 0.002). However, neither CLDN4 nor CLDN7 expression was associated with survival.

Conclusion

In TNBC, the CLDN1-negative phenotype predicts a high risk of recurrence and death. The absence of CLDN1 expression is strongly suggested to be an independent adverse prognostic factor in this heterogeneous subtype of breast cancer.

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.

High expression of indoleamine 2,3-dioxygenase in the tumour is associated with medullary features and favourable outcome in basal-like breast carcinoma

Medullary breast cancer (MBC) is a basal-like breast carcinoma (BLBC) with a favourable outcome, whereas nonmedullary BLBC has a poor prognosis. Tumour infiltrating lymphocytes (TILs) are present in both MBC and BLBC. We hypothesized that the immunosuppressive enzyme indoleamine 2,3-dioxygenase (IDO) could modulate the TILs effects among these tumours and explain their different outcomes. The amount of TILs and IDO expression were analysed using immunohistochemistry (IHC) in 155 BC cases including MBC (n = 17), atypical MBC (n = 13) and non-MBC (n = 125). Messenger RNA expression of the INDO gene, which encodes IDO, was measured in 262 cases from our institution. INDO mRNA expression and histoclinical data of 1,487 BC cases were collected from public databases. IDO immunostaining was present in both neoplastic and stromal cells in 100% of MBC and was associated with histological medullary features among non-MBC cases. There was a significant correlation between IDO positivity and TIL amounts. In our series including mostly grade-3 BC, IDO immunostaining was the most significant marker (p = 0.02) associated with better survival in multivariate analysis. Among our 262 analysed BC cases, INDO mRNA showed significant overexpression in BLBC as compared to luminal A tumours, and in MBC as compared to basal-like non-MBC. In the pooled series of 1,749 BC cases, INDO mRNA was overexpressed in BLBC and was the most significant predictor of better survival in this subtype using multivariate analysis (p = 0.0024). In conclusion, high IDO expression is associated with morphological medullary features and has an independent favourable prognostic value in BLBC.

Expression of MAGE-A and NY-ESO-1 cancer/testis antigens in medullary breast cancer: retrospective immunohistochemical study

Aim

To immunohistochemically evaluate the expression of MAGE-A1, MAGE-A, and NY-ESO-1 cancer/testis (C/T) tumor antigens in medullary breast cancer (MBC) tumor samples and to analyze it in relation to the clinicopathological features.

Methods

This retrospective study included samples from 49 patients: 40 with typical MBC and 9 with atypical MBC. Tumor specimens were obtained from patients operated on in the University Hospital for Tumors and the Sisters of Mercy University Hospital, Zagreb, Croatia, from 1999 to 2005. Standard immunohistochemistry was used on archival paraffin-embedded MBC tissues.

Results

MAGE-A1, MAGE-A, and NY-ESO-1 antigens were expressed in 33% (16/49), 33% (16/49), and 22% (11/49) of patients, respectively. No difference between the groups with and without C/T tumor antigen expression in age at diagnosis, tumor size, axillary lymph node metastasis, adjuvant therapy, and HER-2 expression was identified. Significantly more patients died in the MAGE-A-positive group than in the MAGE-A-negative group (P = 0.010), whereas a borderline significance was found between MAGE-A1-positive and the MAGE-A1-negative group (P = 0.079) and between NY-ESO-1-positive and NY-ESO-1-negative group (P = 0.117). Overall survival, as evaluated by the Kaplan-Meier curves, was lower in MAGE-A1- (P = 0.031), MAGE-A- (P = 0.004), NY-ESO-1-positive groups (P = 0.077).

Conclusion

Expression of C/T antigens may represent a marker of potential prognostic relevance in MBC.

Triple-negative/basal-like breast cancer: review

Breast cancer comprises a heterogeneous group of diseases that vary in morphology, biology, behaviour and response to therapy. Triple-negative (TN) breast cancer is a subtype of tumours with aggressive clinical behaviour which currently lacks effective targeted therapies. The majority of TN breast cancers possess a basal phenotype and show varying degrees of basal marker expression (basal-like tumours). The importance of recognising these tumours came to light largely as the result of global gene expression profiling studies that categorised breast cancer into distinct molecular classes. These studies showed that basal-like tumours are molecularly different from hormone receptors and HER2 positive tumours. Although both TN and basal-like tumours share many molecular and morphological features, equating both tumour classes may be misleading. A better understanding of the molecular and histopathological features of TN and basal-like cancers is of paramount importance, in particular for unravelling the heterogeneous nature of these tumour subgroups and for the identification of prognostic biomarkers, ideal systemic therapy regimens and novel therapeutic targets for these aggressive tumours. In this review, we discuss the difference between TN and basal-like tumours, pathological and clinical features of basal-like cancer and hence explore the criteria that can be used to identify these tumours in routine practice.

Carcinoma medular da mama: correlação anátomo-radiológica

OBJETIVO: Avaliar as características radiológicas do câncer de mama medular em pacientes submetidas a tratamento cirúrgico no Instituto Nacional de Câncer (INCA) - Ministério da Saúde, Rio de Janeiro, RJ, correlacionando os achados com estudo histopatológico. MATERIAIS E MÉTODOS: Foi realizado estudo descritivo retrospectivo de mulheres submetidas a tratamento cirúrgico no INCA, no período de janeiro de 1997 a dezembro de 2006, para identificação das pacientes com carcinoma medular e análise dos achados radiológicos. RESULTADOS: Foram identificadas 21.287 pacientes com diagnóstico de carcinoma neste período, sendo 76 pacientes com diagnóstico de carcinoma medular típico (0,357%). Nessas pacientes selecionadas, a idade média foi de 51,9 anos (32 a 81 anos). Dezenove pacientes apresentavam lesão na mamografia, sendo 17 (89,5%) nódulos e 2 assimetrias focais (10,5%). Entre as pacientes com nódulo, 15 (88,1%) apresentavam alta densidade e 2 eram isodensos (11,9%). Doze pacientes apresentavam achados ultra-sonográficos e, destas, 11 (91,6%) apresentavam nódulos hipoecóicos. Foi observada uma paciente com nódulo anecóico com áreas de degeneração cística. CONCLUSÃO: O nódulo foi o achado radiológico dominante (89,5%), dos quais 88,1% apresentaram nódulos com alta densidade e margens circunscritas. Apesar das características radiológicas de benignidade, um nódulo com alta densidade, sólido, margens circunscritas e crescimento rápido deve ser investigado para confirmar o diagnóstico.

Management of Rare Histological Types of Breast Tumours

Breast tumours exhibit a wide range of morphological phenotypes, and specific histopathological types have particular prognostic and clinical characteristics. The management of uncommon premalignant and malignant lesions is often controversial due to the lack of large single-institution studies or randomised trials to define optimal treatments. In the era of frequent use of treatment guidelines, only a low level of evidence exists for the management of rare histological types of breast tumours. This review is divided into two parts: Firstly, the favourable histological subtypes like tubular, mucinous, medullary breast cancers, and phyllodes tumour (benign, borderline, and malignant) are discussed. The prognosis of these selected lesions is believed to be better than for invasive ductal carcinoma so that in some cases even less aggressive treatment should be considered. Patients with these specific histological types should be informed of this relatively favourable prognosis. Secondly, management recommendations for special situations like Paget's disease (tumour of the nipple) and inflammatory breast carcinoma are presented.

Fine-needle aspiration cytology of medullary breast carcinoma: report of two cases and review of the literature with emphasis on differential diagnosis

Medullary carcinoma is a rare variant of breast carcinoma with a relatively good clinical prognosis as strictly defined. Characteristic features on fine-needle aspiration cytology (FNAC) allow medullary carcinoma to be considered in the cytologic differential diagnosis. We present two FNAC cases with such features, including high cellularity with clusters and single intact malignant cells, bizarre stripped nuclei with prominent nucleoli in a lymphoplasmacytic background, and illustrate one case in liquid-based preparation. Surgical excision revealed that one patient had medullary carcinoma, while the second patient had high-grade infiltrating ductal carcinoma. Breast FNAC samples with syncytial fragments, bizarre nuclei with prominent nucleoli, and a chronic inflammatory infiltrate should raise the possibility of medullary carcinoma. However, the differential diagnosis also includes high-grade ductal carcinoma, lymphoma, or metastasis to breast or intramammary lymph nodes; thus, histopathologic analysis is required for definitive diagnosis.

Sporadic Invasive Breast Carcinomas With Medullary Features Display a Basal-like Phenotype

It is not clear whether invasive breast carcinomas with medullary features (IBCMFs, atypical medullary carcinomas) constitute a specific phenotype of breast cancer that is of biologic significance. Because medullary features are common in BRCA1-associated carcinomas and these tumors frequently show a basal-like phenotype, we examined whether IBCMFs expressed basal/myoepithelial markers and had a basal-like phenotype. We studied the immunohistochemical expression of 15 markers in tissue microarrays containing samples from 35 IBCMFs and 39 grade 3 invasive ductal carcinomas (IDCG3s) of no special type. In addition, we analyzed EGFR, C-MYC, and CCNE gene amplification by fluorescence in situ hybridization, because the expression of these genes is known to be associated with the basal-like phenotype. We defined the basal-like phenotype according to the criteria of Nielsen et al as being those tumors that were ER/HER2-negative and cytokeratin (CK) 5/6- and/or epidermal growth factor receptor-positive. IBCMFs were more frequently hormone receptor- and HER2-negative, but had greater expression of proliferation markers and p53. In addition, IBCMFs more frequently expressed basal/myoepithelial markers, such as CK5/6 and P-cadherin. A basal-like phenotype was found in 62.9% of IBCMFs but in only 18.9% of IDCG3s. No differences in gene amplification were found between IBCMFs and IDCG3s, although C-MYC amplification was more common in tumors without a basal-like phenotype. The identification of IBCMF as an independent group of tumors could be of clinical significance, given the high incidence of cases with a basal-like phenotype, which is a group of tumors with different prognosis and chemotherapy response from those of IDCG3s of no special type.

Moesin expression is a marker of basal breast carcinomas

Basal breast cancers (BBCs) have a high risk of metastasis, recurrence and death. Formal subtype definition relies on gene expression but can be approximated by protein expression. New markers are needed to help in the management of the basal subtype of breast cancer. In a previous transcriptional analysis of breast cell lines we found that Moesin expression was a potential basal marker. We show here that Moesin protein expression is a basal marker in breast tumors. In a tissue microarray (TMA) containing 547 sporadic breast cancers, of which 108 were profiled for gene expression, Moesin was expressed in 31% of all tumors and in 82% of the basal tumors. To confirm that Moesin expression remained associated with the basal phenotype in specific types of BBCs, we analyzed Moesin expression in 2 other TMAs containing 40 medullary breast cancers (MBCs) and 27 BRCA1-associated breast cancers (BRCA1-BCs), respectively. Moesin was strongly expressed in MBCs (87%; p = 2.4 x 10(-5)) and in BRCA1-BCs (58%; p = 1.3 x 10(-5)) as compared with non-MBCs and sporadic cases. Moesin-expressing tumors display features of BBCs, such as high proliferation rate, hormone receptors negativity, expression of putative basal/myoepithelial markers (CAV1, CD10, CK5/6, CK14, EGFR, P53, P-cadherin and SMA). Survival analysis showed a reduced specific survival and metastasis-free survival in Moesin-expressing tumors by log-rank test (p(SS) = 0.014 and p(MFS) = 0.014). In multivariate analysis, Moesin expression was nearly an independent prognostic marker of poor outcome as shown by Cox proportional hazard model in patients without lymph node metastasis (p = 0.052, HR = 2.38, CI 95[0.99-5.69]).

Gene expression profiling shows medullary breast cancer is a subgroup of basal breast cancers

Medullary breast cancer (MBC) is a rare but enigmatic pathologic type of breast cancer. Despite features of aggressiveness, MBC is associated with a favorable prognosis. Morphologic diagnosis remains difficult in many cases. Very little is known about the molecular alterations involved in MBC. Notably, it is not clear whether MBC and ductal breast cancer (DBC) represent molecularly distinct entities and what genes/proteins might account for their differences. Using whole-genome oligonucleotide microarrays, we compared gene expression profiles of 22 MBCs and 44 grade III DBCs. We show that MBCs are less heterogeneous than DBCs. Whereas different molecular subtypes (luminal A, luminal B, basal, ERBB2-overexpressing, and normal-like) exist in DBCs, 95% MBCs display a basal profile, similar to that of basal DBCs. Supervised analysis identified gene expression signatures that discriminated MBCs from DBCs. Discriminator genes are associated with various cellular processes related to MBC features, in particular immune reaction and apoptosis. As compared with MBCs, basal DBCs overexpress genes involved in smooth muscle cell differentiation, suggesting that MBCs are a distinct subgroup of basal breast cancer with limited myoepithelial differentiation. Finally, MBCs overexpress a series of genes located on the 12p13 and 6p21 chromosomal regions known to contain pluripotency genes. Our results contribute to a better understanding of MBC and of mammary oncogenesis in general.

PIK3CA mutation and histological type in breast carcinoma: high frequency of mutations in lobular carcinoma

Mutations in the PIK3CA gene have recently been reported in different human neoplasms, including breast cancer. This paper reports the results of a systematic analysis of PIK3CA mutations in different histological types of breast carcinoma. One hundred and eighty invasive breast carcinomas, comprising 74 ductal, 56 lobular, 22 mucinous, 20 medullary, and eight papillary, were selected on the basis of their histological type in a consecutive series of 780 breast cancers. Exons 1-20 of the PIK3CA gene were subjected to SSCP analysis followed by direct sequencing. PIK3CA mutations were observed in 46 (26%) of the 180 tumours examined: 23 (50%) mutations were located in exon 9, and 23 (50%) in exon 20. Mutations were frequent in lobular (46%), less frequent in ductal (22%), and uncommon in medullary (10%), mucinous (5%), and papillary tumours (12%) (p = 0.0002). Mutations in exon 9 were more frequent in lobular carcinomas (30% of cases) than in the other histological types (less than 5% of cases) (p = 0.00014). No significant differences were observed in the distribution of mutations in exon 20. There was no significant correlation between PIK3CA mutations and other clinicopathological and biological variables, including age, tumour size, lymph node metastases, oestrogen receptor (ER) status, progesterone receptor (PgR) status, p53 gene mutations, and p53 protein expression. The findings indicate that in invasive breast carcinomas, PIK3CA alterations are mainly present in lobular and ductal tumours, whereas the other histological types, known to be associated with a favourable prognosis, show a very low incidence of PIK3CA mutations.

Typical medullary breast carcinomas have a basal/myoepithelial phenotype

Medullary breast cancer (MBC) is a rare, diagnostically difficult, pathological subtype. Despite being high grade, it has a good prognosis. MBC patients have an excess of BRCA1 germ-line mutation and reliable identification of MBC could help to identify patients at risk of carrying germline BRCA1 mutations or in whom chemotherapy could be avoided. The aim of this study was therefore to improve diagnosis by establishing an MBC protein expression profile using immunohistochemistry (IHC) on tissue-microarrays (TMA). Using a series of 779 breast carcinomas ('EC' set), diagnosed initially as MBC, a double-reading session was carried out by several pathologists on all of the histological material to establish the diagnosis as firmly as possible using a 'medullary score'. Only MBCs with high scores, i.e. typical MBC (TMBC) (n=44) and non-TMBC grade III with no or low scores (n=160), were included in the IHC study. To validate the results obtained on this first set, a control series of TMBC (n=17) and non-MBC grade III cases (n=140) ('IPC' set) was studied. The expression of 18 proteins was studied in the 61 TMBCs and 300 grade III cases from the two sets. The global intra-observer concordance of the first reading for the diagnosis of TMBC was 94%, with almost perfect kappa (kappa) of 0.815. TMBC was characterized by a high degree of basal/myoepithelial differentiation. In multivariate analysis with logistic regression, TMBC was defined by the association of P-cadherin (R=2.29), MIB1 > 50 (R=3.80), ERBB2 negativity (R=2.24) and p53 positivity (RR=1.45).