Dermal lymphatic emboli in inflammatory and noninflammatory breast cancer: a French-Tunisian joint study in 337 patients

Inflammatory breast cancer: An overview about the histo-pathological aspect and diagnosis

Inflammatory Breast Cancer (IBC) is a rare and aggressive form of locally advanced breast cancer, classified as stage T4d according to the tumor-node-metastasis staging criteria. This subtype of breast cancer is known for its rapid progression and significantly lower survival rates compared to other forms of breast cancer. Despite its distinctive clinical features outlined by the World Health Organization, the histopathological characteristics of IBC remain not fully elucidated, presenting challenges in its diagnosis and treatment. Histologically, IBC tumors often exhibit a ductal phenotype, characterized by emboli composed of pleomorphic cells with a high nuclear grade. These emboli are predominantly found in the papillary and reticular dermis of the skin overlaying the breast, suggesting a primary involvement of the lymphatic vessels. The tumor microenvironment in IBC is a complex network involving various cells such as macrophages, monocytes, and predominantly T CD8+ lymphocytes, and elements including blood vessels and extracellular matrix molecules, which play a pivotal role in the aggressive nature of IBC. A significant aspect of IBC is the frequent loss of expression of hormone receptors like estrogen and progesterone receptors, a phenomenon that is still under active investigation. Moreover, the overexpression of ERBB2/HER2 and TP53 in IBC cases is a topic of ongoing debate, with studies indicating a higher prevalence in IBC compared to non-inflammatory breast cancer. This overview seeks to provide a comprehensive understanding of the histopathological features and diagnostic approaches to IBC, emphasizing the critical areas that require further research.

Inflammatory breast cancer defined: proposed common diagnostic criteria to guide treatment and research

Purpose

Inflammatory breast cancer is a deadly and aggressive type of breast cancer. A key challenge relates to the need for a more detailed, formal, objective definition of IBC, the lack of which compromises clinical care, hampers the conduct of clinical trials, and hinders the search for IBC-specific biomarkers and treatments because of the heterogeneity of patients considered to have IBC.

Methods

Susan G. Komen, the Inflammatory Breast Cancer Research Foundation, and the Milburn Foundation convened patient advocates, clinicians, and researchers to review the state of IBC and to propose initiatives to advance the field. After literature review of the defining clinical, pathologic, and imaging characteristics of IBC, the experts developed a novel quantitative scoring system for diagnosis.

Results

The experts identified through consensus several “defining characteristics” of IBC, including factors related to timing of onset and specific symptoms. These reflect common pathophysiologic changes, sometimes detectable on biopsy in the form of dermal lymphovascular tumor emboli and often reflected in imaging findings. Based on the importance and extent of these characteristics, the experts developed a scoring scale that yields a continuous score from 0 to 48 and proposed cut-points for categorization that can be tested in subsequent validation studies.

Conclusion

To move beyond subjective ‘clinical diagnosis’ of IBC, we propose a quantitative scoring system to define IBC, based on clinical, pathologic, and imaging features. This system is intended to predict outcome and biology, guide treatment decisions and inclusion in clinical trials, and increase diagnostic accuracy to aid basic research; future validation studies are necessary to evaluate its performance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-021-06434-x.

Dermal Lymphatic Invasion, Survival, and Time to Recurrence or Progression in Inflammatory Breast Cancer

OBJECTIVES

Dermal lymphatic invasion (DLI) with tumor emboli is a common pathologic characteristic of inflammatory breast cancer (IBC), although its presence is not required for diagnosis. We examined whether documented DLI on skin biopsy was associated with survival and time to recurrence or progression in IBC.

MATERIALS AND METHODS

A total of 340 women enrolled in the IBC Registry at Dana-Farber Cancer Institute between 1997 and 2019 were included in this study. Kaplan-Meier curves and multivariable Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals for associations of DLI and overall survival, time to locoregional recurrence/progression, and distant metastasis by stage at presentation.

RESULTS

DLI was detected in 215 (63.2%) of IBC cases overall. At disease presentation, IBC with DLI had a higher prevalence of de novo metastases (37.7% vs. 26.4%), breast skin ulceration (6.1% vs. 2.4%), and lymphovascular invasion within the breast parenchyma (52.9% vs. 25.5%) and a lower prevalence of palpable breast mass (48.2% vs. 70.6%) than IBC without DLI. Over a median follow-up of 2.0 years, 147 deaths occurred. DLI was not associated with survival or recurrence in multivariable models (all P ≥0.10). For example, among women with stage III disease, hazard ratios (95% confidence intervals) for DLI presence was 1.29 (0.77-2.15) for overall survival, 1.29 (0.56-3.00) for locoregional recurrence, and 1.71 (0.97-3.02) for distant metastasis.

CONCLUSION

Although the extent of tumor emboli in dermal lymphatics may be associated with biological features of IBC, DLI was not an independent prognostic marker of clinical outcomes in this study.

Clinico-pathologic and mammographic characteristics of inflammatory and non-inflammatory breast cancer at six centers in North Africa

PURPOSE

We describe the clinico-pathologic and mammographic characteristics of inflammatory breast cancer (IBC) and non-IBC cases enrolled in a case-control study. Because IBC is a clinico-pathologic entity with rapid appearance of erythema and other signs, its diagnosis is based on clinical observation and thus, by necessity, subjective. Therefore, we evaluate our cases by photographic review by outside expert clinicians and by degree of adherence to the two most recent definitions of IBC: the international expert panel consensus statement and American Joint Committee on Cancer (AJCC) 8th edition (we used the slightly less restrictive 7th edition definition for our study).

METHODS

We enrolled 267 IBC and 274 age- and geographically matched non-IBC cases at 6 sites in Egypt, Tunisia, and Morocco in a case-control study of IBC conducted between 2009 and 2015. We collected clinico-pathologic and mammographic data and standardized medical photographs of the breast.

RESULTS

We identified many differences between IBC and non-IBC cases: 54.5% versus 68.8% were estrogen receptor-positive, 39.9% versus 14.8% human epidermal growth factor receptor 2-positive, 91% versus 4% exhibited erythema, 63% versus 97% had a mass, and 57% versus 10% had mammographic evidence of skin thickening. Seventy-six percent of IBC cases adhered to the expert panel consensus statement and 36% to the AJCC definition; 86 percent were confirmed as IBC by either photographic review or adherence to the consensus statement.

CONCLUSIONS

We successfully identified distinct groups of IBC and non-IBC cases. The reliability of IBC diagnosis would benefit from expert review of standardized medical photographs and associated clinical information.

Inflammatory breast cancer: no longer an absolute contraindication for breast conservation surgery following good response to neoadjuvant therapy

Inflammatory breast cancer (IBC) is a rare form of breast cancer characterised by an erythematous swollen breast with extensive oedema and has in the past been associated with a very poor prognosis. After diagnosis by core biopsy of the cancer and any involved nodes patients in the Edinburgh Breast Unit (EBU) are primarily managed with neoadjuvant systemic therapy-chemotherapy or endocrine therapy. If the cancer is localised to one or a few well defined lesions then each of these lesions together with the lowest involved node are clipped. Response during neoadjuvant treatment is monitored clinically and by ultrasound plus mammography +/- magnetic resonance imaging (MRI). Following completion of neoadjuvant therapy, imaging is reviewed at a multidisciplinary meeting and patients with a localised single or multiple areas of cancer where all signs of erythema and oedema have settled are considered as to their suitability for breast conserving surgery and whole breast radiotherapy [breast conserving treatment (BCT)]. Here we discuss the results and outcomes of a selected group of patients with IBC who after obtaining a very good response to neoadjuvant chemotherapy or endocrine therapy were treated by BCT and we compare these with other recent publications on this topic. Our data show that patients treated by BCT did not have worse outcomes than patients treated with mastectomy. Importantly other series published recently support our conclusions. Another important observation is that response in estrogen receptor (ER) rich IBC is seen with neoadjuvant endocrine treatment and so not everyone with IBC needs to have neoadjuvant chemotherapy. In conclusion, patients with one or more well defined and localised breast masses and IBC may be suitable for BCT after a major response to neoadjuvant therapy and for these patients BCT should now be considered a viable option.

Biological features of inflammatory breast cancer in North Africa: burden and research priorities

We aimed to review all published literature reporting biological data about inflammatory breast cancer (IBC) in populations from North Africa. Methods: We reviewed all studies that evaluated biological features of IBC in six North African countries between 1990 and 2017. Among 118 screened studies, 13 were included, none about Mauritania/Libya. Results: Across the studies, hormonal receptors were positive in 46–69% of cases, reaching 83% in Algeria. HER2 was overexpressed in 25–39% of cases. Recombinant human C protein expression was the highest in Egyptian patients (87%) compared with other North African populations. Using mRNA expression recombinant human C protein was expressed in 83% of Tunisian patients. WISP3 gene expression showed positive immunohistochemistry staining in 17% and mRNA expression in 26.8% of IBC. Conclusion: Biological aspects of IBC across North Africa show important similarities and differences.

Comparative aspects of canine and human inflammatory breast cancer

Inflammatory breast cancer (IBC) in humans is the most aggressive form of mammary gland cancer and shares clinical, pathologic, and molecular patterns of disease with canine inflammatory mammary carcinoma (CIMC). Despite the use of multimodal therapeutic approaches, including targeted therapies, the prognosis for IBC/CIMC remains poor. The aim of this review is to critically analyze IBC and CIMC in terms of biology and clinical features. While rodent cancer models have formed the basis of our understanding of cancer biology, the translation of this knowledge into improved outcomes has been limited. However, it is possible that a comparative "one health" approach to research, using a natural canine model of the disease, may help advance our knowledge on the biology of the disease. This will translate into better clinical outcomes for both species. We propose that CIMC has the potential to be a useful model for developing and testing novel therapies for IBC. Further, this strategy could significantly improve and accelerate the design and establishment of new clinical trials to identify novel and improved therapies for this devastating disease in a more predictable way.

Inflammatory Breast Cancer: A Distinct Clinicopathological Entity Transcending Histological Distinction

Introduction

Although well recognized in breast oncology literature, histologic subtypes have not been previously described in inflammatory breast cancer (IBC). The purpose of this study was to describe lobular subtype in IBC and assess the impact of histology on patient outcomes.

Methods

We performed a retrospective analysis of 659 IBC patients at MD Anderson Cancer Center between January 1984 and December 2009. Patients with Invasive Lobular, Mixed Invasive Ductal and Lobular, or Invasive Ducal Carcinomas (ILC, MIC, IDC, respectively) comprise the subject of this report. Patient characteristics and survival estimates were compared by using chi-square test and Kaplan-Meier method with log-rank statistic. Cox proportional hazards models were fit to determine association of histology with outcomes after adjustment for other characteristics.

Results

A total of 30, 37, and 592 patients were seen to have invasive lobular, mixed, or ductal histology, respectively. Grade 3 tumors were more common in the ductal group (78%) than in the lobular (60%) or mixed (61%) group (P = 0.01). The 3-year overall survival rates were 68%, 64%, and 62% in the lobular, mixed, and ductal groups, respectively (P = 0.68). After adjustment, histology did not have a significant effect on death in the lobular group (HR = 0.70, 95% confidence interval [CI]: 0.26–1.94; P = 0.50) or mixed group (HR = 0.53, 95% CI: 0.25–1.13; P = 0.10) compared with the ductal group.

Conclusion

In this cohort of IBC patients, lobular histology was seen in 4.5% cases. Histology does not appear to have a significant effect on survival outcomes in IBC patients, unlike in patients with non-inflammatory breast cancer (n-IBC), indicating the distinct biological behavior of the IBC phenotype.

Inflammatory breast cancer in Tunisia from 2005 to 2010: epidemiologic and anatomoclinical transitions from published data

AIM

To report epidemiologic and anatomoclinical transitions of inflammatory breast cancer (IBC) in Tunisia.

MATERIALS AND METHODS

Data including clinico-pathological data for208 cases of T4d or PEV 3 non-metastatic breast cancer diagnosed between 2005 and 2010 were collected from patient records. Chi2 and Z tests were used to compare variables with two Tunisian historical series and a series about Arab-American patients.

RESULTS

Thirty three percent of our patients had their first child before 23 years of age and 56% had their menarche before 12 years, 75% never receiving oral contraception. Obesity was observed in 42% of women and IBC occurred during pregnancy in 13% of cases. Tumor grade was II-III in 90% of cases, HR was negative in 52%, HER2 was over expressed in 31% and invasion of more than 3 axillary nodes occurred in 18% of patients. We observed a pCR rate of 19% after neoadjuvant treatment (anthracyline-taxane used in 79%, trastuzumab in 27% ). Compared to historical Tunisian series (since 1996), IBC epidemiology remained stable in terms of median age, menopausal status and obesity. However we observed a significant decrease in median clinical tumor size and number of positive axillary lymph nodes. Comparison to IBC in Arab-Americans showed a significant difference in terms of median age, menopausal status, positivity of hormonal receptors and educational level.

CONCLUSIONS

Our assessment of epidemiologic transition showed a reduction of clinco-pathological stage of IBC, keeping the same characteristics as compared to Tunisian historical series over a period of 14 years. Features seem to be different in Arab-American patients, probably related to migration, "occidentalization" of life style and improvement in socio-economic level.

Receptor-defined subtypes of breast cancer in indigenous populations in Africa: a systematic review and meta-analysis

BACKGROUND

Breast cancer is the most common female cancer in Africa. Receptor-defined subtypes are a major determinant of treatment options and disease outcomes but there is considerable uncertainty regarding the frequency of poor prognosis estrogen receptor (ER) negative subtypes in Africa. We systematically reviewed publications reporting on the frequency of breast cancer receptor-defined subtypes in indigenous populations in Africa.

METHODS AND FINDINGS

Medline, Embase, and Global Health were searched for studies published between 1st January 1980 and 15th April 2014. Reported proportions of ER positive (ER+), progesterone receptor positive (PR+), and human epidermal growth factor receptor-2 positive (HER2+) disease were extracted and 95% CI calculated. Random effects meta-analyses were used to pool estimates. Fifty-four studies from North Africa (n=12,284 women with breast cancer) and 26 from sub-Saharan Africa (n=4,737) were eligible. There was marked between-study heterogeneity in the ER+ estimates in both regions (I2>90%), with the majority reporting proportions between 0.40 and 0.80 in North Africa and between 0.20 and 0.70 in sub-Saharan Africa. Similarly, large between-study heterogeneity was observed for PR+ and HER2+ estimates (I2>80%, in all instances). Meta-regression analyses showed that the proportion of ER+ disease was 10% (4%-17%) lower for studies based on archived tumor blocks rather than prospectively collected specimens, and 9% (2%-17%) lower for those with ≥ 40% versus those with <40% grade 3 tumors. For prospectively collected samples, the pooled proportions for ER+ and triple negative tumors were 0.59 (0.56-0.62) and 0.21 (0.17-0.25), respectively, regardless of region. Limitations of the study include the lack of standardized procedures across the various studies; the low methodological quality of many studies in terms of the representativeness of their case series and the quality of the procedures for collection, fixation, and receptor testing; and the possibility that women with breast cancer may have contributed to more than one study.

CONCLUSIONS

The published data from the more appropriate prospectively measured specimens are consistent with the majority of breast cancers in Africa being ER+. As no single subtype dominates in the continent availability of receptor testing should be a priority, especially for young women with early stage disease where appropriate receptor-specific treatment modalities offer the greatest potential for reducing years of life lost. Please see later in the article for the Editors' Summary.

Inflammatory breast cancer in north Africa: comparison of clinical and molecular epidemiologic characteristics of patients from Egypt, Tunisia, and Morocco

Understanding molecular characteristics that distinguish inflammatory breast cancer (IBC) from non-IBC is crucial for elucidating breast cancer etiology and management. We included 3 sets of patients from Egypt (48 IBC and 64 non-IBC), Tunisia (24 IBC and 40 non-IBC), and Morocco (42 IBC and 41 non-IBC). Egyptian IBC patients had the highest combined erythema, edema, peau d'orange, and metastasis among the 3 IBC groups. Egyptian IBC tumors had the highest RhoC expression than Tunisians and Moroccan IBCs (87% vs. 50%, vs. 38.1, for the 3 countries, respectively). Tumor emboli were more frequent in Egyptian IBC than non-IBC (Mean ± SD: 14.1 ± 14.0 vs. 7.0 ± 12.9, respectively) (P < 0.001) and Tunisians (Mean ± SD: 3.4 ± 2.5 vs. 1.9 ± 2.0, respectively) (P < 0.01). There was no difference of emboli in Moroccan tumors (1.7 ± 1.2 vs. 1.8 ± 1.2 for IBC and non-IBC, respectively (P=0.66). This study illustrates that RhoC overexpression and tumor emboli are more frequent in IBC relative to non-IBC from Egypt and Tunisia. Tumors of Moroccans were significantly different from Egyptian and Tunisian tumors for RhoC expression and emboli. Future studies should focus on relating epidemiologic factors and clinical pictures to molecular features of IBC in these and other populations.

Breast cancer in Arab populations: molecular characteristics and disease management implications

Breast cancer is a major health problem in both developing and developed countries. It is the most frequently diagnosed female malignant disease in Arab populations. The incidence of breast cancer is lower in Arab countries than in Europe and the USA but is rising fast. Breast cancers in women from Arab populations have different characteristics to those reported in individuals from Europe and the USA. For example, affected patients are at least a decade younger, they have a more advanced stage of disease at first presentation, and their tumour size is larger. Moreover, in some Arab populations, reports suggest increased axillary-lymph-node invasion, a larger proportion of negative hormone receptors, and a higher tumour grade. These disparities are not only confined to clinicopathological features but also exist at the molecular level, as shown by findings of genome-wide association studies and expression profiling.

Characterizing inflammatory breast cancer among Arab Americans in the California, Detroit and New Jersey Surveillance, Epidemiology and End Results (SEER) registries (1988-2008)

Introduction

Inflammatory breast cancer (IBC) is characterized by an apparent geographical distribution in incidence, being more common in North Africa than other parts of the world. Despite the rapid growth of immigrants to the United States from Arab nations, little is known about disease patterns among Arab Americans because a racial category is rarely considered for this group. The aim of this study was to advance our understanding of the burden of IBC in Arab ethnic populations by describing the proportion of IBC among different racial groups, including Arab Americans from the Detroit, New Jersey and California Surveillance, Epidemiology and End Results (SEER) registries.

Methods

We utilized a validated Arab surname algorithm to identify women of Arab descent from the SEER registries. Differences in the proportion of IBC out of all breast cancer and IBC characteristics by race and menopausal status were evaluated using chi-square tests for categorical variables, t-tests and ANOVA tests for continuous variables, and log-rank tests for survival data. We modeled the association between race and IBC among all women with breast cancer using hierarchical logistic regression models, adjusting for individual and census tract-level variables.

Results

Statistically significant differences in the proportion of IBC out of all breast cancers by race were evident. In a hierarchical model, adjusting for age, estrogen and progesterone receptor, human epidermal growth receptor 2, registry and census-tract level education, Arab-Americans (OR=1.5, 95% CI=1.2,1.9), Hispanics (OR=1.2, 95% CI=1.1,1.3), Non-Hispanic Blacks (OR=1.3, 95% CI=1.2, 1.4), and American Indians/Alaskans (OR=1.9, 95% CI=1.1, 3.4) had increased odds of IBC, while Asians (OR=0.6, 95% CI=0.6, 0.7) had decreased odds of IBC as compared to Non-Hispanic Whites.

Conclusions

IBC may be more common among certain minority groups, including Arab American women. Understanding the descriptive epidemiology of IBC by race may generate hypotheses about risk factors for this aggressive disease. Future research should focus on etiologic factors that may explain these differences.

Evaluation of lymphangiogenic factors, vascular endothelial growth factor D and E-cadherin in distinguishing inflammatory from locally advanced breast cancer

BACKGROUND

Inflammatory breast cancer (IBC) is an aggressive form of breast cancer that on presentation resembles locally advanced breast cancer (LABC). This study identified molecular features of IBC and LABC to investigate pathogenesis.

MATERIALS AND METHODS

This study involved 100 IBC cases identified in a national IBC registry and 107 non-IBC LABC cases from the National Cancer Institute's Cooperative Breast Cancer Tissue Resource (CBCTR). Vascular endothelial growth factor D (VEGF-D) and E-cadherin levels and lymphatic vessel density (LVD) measured by podoplanin staining were examined by immunohistochemistry on paraffin-embedded tumor specimens. Intralymphatic tumor emboli (ILTE) were assessed in IBC and non-IBC tumors. IBC cases diagnosed by clinicians but not meeting the case definitions of the American Joint Committee on Cancer (AJCC) or the Surveillance, Epidemiology and End Results (SEER) Program of the National Cancer Institute (NCI)(designated atypical IBC) were compared with AJCC- and/or SEER-defined cases (designated classic IBC).

RESULTS

E-cadherin levels were significantly higher in classic IBC cases compared with non-IBC cases (P = .031), whereas compared with classic IBC, patients with non-IBC LABC had significantly higher LVD (P = .0017) and VEGF-D levels (P < .0001). ILTE was marginally greater in classic IBC than in non-IBC (P = .046). The profile of laboratory values in atypical IBC cases more closely resembled those fitting classic IBC than LABC.

CONCLUSION

E-cadherin levels, LVD, VEGF-D expression, and to a lesser extent, ILTE differed between classic IBC and non-IBC LABC. The similarity of laboratory results between atypical IBC and classic IBC vs. LABC suggests the need for broadening both the AJCC and SEER case definitions for this disease.

Molecular and epidemiological characteristics of inflammatory breast cancer in Algerian patients

Inflammatory breast cancer (IBC) shows a high incidence in Tunisia and Egypt but epidemiological and molecular characteristics have not been described in Algeria. We compared 117 IBC and 59 non-IBC locally advanced breast cancers (LABC), for estrogen and progesterone receptors, HER2, and EGFR protein expression by immunohistochemistry, and HER2 gene amplification by chromogenic in situ hybridization. Demographic, clinico-pathological, and molecular variables were compared with chi-square and Fisher's exact tests to test for significance (P < 0.05, two-tailed). Overall survival (OS) and disease-free survival (DFS) were plotted using Kaplan-Meier curves and compared using the log-rank test. Tumor emboli were detected in 77% of IBC. Palpable masses were found in all LABC but only in 32% of IBC (P < 0.001). Recurrences were higher in LABC than in IBC (48 vs. 35%; P = 0.14) but OS was worse in IBC (68 vs. 71%; P = 0.06). There were no significant differences between IBC and LABC by demographics or by clinico-pathological parameters. The majority of IBC and LABC tumors were luminal A (62 and 64%), followed by basal (~18%, each), triple negative (~18%, each), and HER2+ (~10%, each) subtypes. In multivariate analyses, grade was associated with worse OS (P = 0.04), and DFS (P < 0.001) in IBC; chemo- and radio-therapy were associated with improved OS and DFS, respectively (P < 0.05 for each) in LABC. In conclusion, IBC in Algeria shows similar characteristics to IBC described for Egypt and Tunisia with subtle molecular differences. Current therapeutic treatments were not very effective in this population and new approaches are much needed.

Inflammatory breast cancer in Tunisia: epidemiological and clinical trends

Inflammatory breast cancer (IBC) is characterized by a peculiar geographic distribution in incidence, being described as more common in Tunisia and the region of North Africa. The authors performed a systematic review of published literature on rapidly progressing breast cancer and IBC in Tunisia and analyzed the evolution in epidemiology, clinical presentation, treatment, and therapeutic results. They collected, analyzed, and compared all the indexed Tunisian articles about rapidly progressing breast cancer and IBC since the 1970s opening of the Institut Salah Azaiz Institute in Tunis. In the 1970s, rapidly progressing breast cancer diagnosis was based on the Poussée Evolutive classification (1-3). Since the 1990s, IBC diagnosis has been based on the American Joint Committee on Cancer Poussée Evolutive 3/T4d staging. The authors compared the historical data to the most recent publications in terms of epidemiology, clinical features, treatment, and therapeutic results. The most important historical report of rapidly progressing breast cancer concerned 340 patients, representing 58.5% of a cohort of 581 breast cancer patients collected from 1969 to 1974, including 320 (55.2%) with inflammatory signs, 37(6.5%) with Poussée Evolutive 2, and 283 (48.7%) with Poussée Evolutive 3. Subsequent papers have documented a steady decrease in incidence to the current 5% to 7% T4d/IBC. Since the 1970s, Poussée Evolutive in premenopausal woman has increased from 52.5% to 75%; rural predominance has persisted. The 5-year overall survival reached 28% by the year 2000. The authors' analysis demonstrated a trend of decreasing incidence of IBC diagnoses from 50% to presently <10%, probably related to a combination of factors, including the use of more stringent criteria (Poussée Evolutive 3/T4d) for IBC diagnosis and an improvement in the socioeconomic level of Tunisia.

Molecular epidemiologic features of inflammatory breast cancer: a comparison between Egyptian and US patients

BACKGROUND

Inflammatory breast cancer (IBC) is a lethal form of breast cancer with unknown etiology. A higher frequency of IBC and a more aggressive IBC phenotype was reported in Egypt than in the United States. This difference in disease frequency and presentation might be related to molecular epidemiologic factors.

METHODS

We used tumor blocks and demographic, epidemiologic, and clinical data of 48 IBC patients from Egypt and 12 patients from the United States. We counted tumor emboli in tumors before and after immunohistochemical staining with lymphatic vessel endothelial receptor-1 (LYVE-1), and measured the expression of RhoC GTPase protein in the two groups.

RESULTS

Erythema, edema, and peau d'orange were found in 77% of the Egyptian patients as compared with 29% found in the US patients (P=0.02). The number of tumor emboli was significantly higher in tumors from Egypt (mean+/-SD, 14.1+/-14.0) than in the tumors from the United States (5.0+/-4.0, P=0.01). The number of tumor emboli in LYVE-1 positive vessels was higher in tumors from Egypt (3.5+/-2.8) than tumors from the United States (1.6+/-0.5, P=0.15). We detected a high level of RhoC in 87% of the tumors from Egypt and 14% of the tumors from the United States (P=0.0003).

CONCLUSION

Patients from Egypt have a more aggressive form of IBC than those in the United States. Our analysis of IBC patients shows that distinct molecular phenotypes can be found when these two study populations are compared. Future studies should explore the epidemiologic and environmental exposures and the genetic factors that might lead to the different clinical and molecular features of IBC in patients from these two countries.

T4 breast cancer under closer inspection: A case for revision of the TNM classification

The presence of skin involvement in breast cancer results in the classification of the tumor into the highest tumor category, and accordingly into the highest non-metastatic disease stage (current TNM classification: T4/stage III). This traditional view is no longer justifiable, as tumors that show non-inflammatory skin involvement (T4b) make up a considerably heterogeneous group with a high percentage of small-sized tumors. Classifying all lesions demonstrating this feature together results in the combination of tumors with widely differing prognostic and therapeutic implications into a single group. This violates the basic principle of the TNM concept in that only tumors exhibiting similar extension and prognosis should be grouped into one category/stage. Furthermore, the currently valid definitions of non-inflammatory skin involvement are misconceived for the substantial group of small tumors which often have ambiguous morphologic findings: the clinical classification depends on the subjective perception of the individual observer, and the pathologic staging considers histologic criteria that are not justifiable from a functional-morphological point of view. For these reasons, we strongly feel that there is a need to revise the current T4 category. We recommend that breast carcinomas currently classified as T4a-c should be eliminated from the T4 category and classified simply according to their tumor size (T1-3). The prognostically very unfavorable inflammatory carcinoma (T4d) should be maintained as the only clinicopathologic entity in the T4 category. This proposal, which will also lead to a revision of the stage III group, adheres more closely to the goals and principles of the TNM classification than do the current classification guidelines. Through the revision of the T4 category, the definitions and guidelines of inflammatory breast carcinoma should be adapted to the internationally accepted nomenclature.

Inflammatory breast cancers in Tunisia and France show similar immunophenotypes

PURPOSE

Inflammatory breast cancers (IBC) have specific immunophenotypic profiles as compared to non-inflammatory (non-IBC): combined differential expression of estrogen receptor, Ki67, E-cadherin, MUC1, and ERBB2 can be used as an IBC signature. It is thought that IBC occurs with a high frequency in Tunisia. The aim of this study is to evaluate this signature on a Tunisian series.

METHODS

The expression of five proteins (E-cadherin, ERBB2, estrogen receptor, Ki67, MUC1) was studied by immunohistochemistry on a consecutive series of 91 cases of IBC (T4D) treated at Tunisian Salah Azaiz Institute (ISA) and deposited in a tissue microarray (TMA). Results were compared to the same study on a series of 85 cases treated in France.

RESULTS

The ISA cases were characterized by a significantly younger age of patients (median: 42 years old in ISA for 53.5 in IPC, p=0.00042) and a higher frequency of invasive micropapillary pattern. None of the five parameters was expressed differentially in the two series. In non-metastatic patients, high level of proliferation (Ki67) and overexpression of ERBB2 were associated with poor outcome.

CONCLUSION

The IBC from Tunisia were not different from those observed in France on the basis of IHC profiles. However, the younger age of the patients suggest a specific epidemiological context that should be investigated.

Use of immunohistochemistry in diagnosis of breast epithelial lesions

In recent years, the use of immunohistochemistry (IHC) in breast pathology has increased tremendously. It is not because the new genre of breast pathologists are less well trained than their "experienced" counterparts; it is mainly because of the demands of more accurate and precise diagnoses, identification of new entities and availability of novel antibodies. The main purpose of this review is to discuss the use of best available antibodies in diagnoses of breast epithelial lesions. The following items are discussed: assessment of invasion, IHC in papillary lesions, identification of breast tumor subtypes, IHC in proliferative breast lesions, assessment of lymphatic space invasion, diagnosis of metaplastic breast carcinoma, IHC in Paget disease, use of cytokeratins in sentinel lymph node assessment, and diagnosis of breast carcinoma at metastatic sites. Because the main focus of this review is on diagnosis, receptor studies on breast carcinoma are briefly discussed and only a few general comments are made.

Are risk factors for breast cancer similar in women with inflammatory breast cancer and in those with non-inflammatory breast cancer?

PURPOSE

The aim of the study was to compare reproductive factors in patients with inflammatory breast cancer (IBC), and with non-inflammatory breast cancer (non-IBC). The study was performed in two centers: one French including 49 IBC patients and 140 non-IBC and another Tunisian including 97 IBC and 139 non-IBC. Unconditional logistic regression was used for the analyses.

PATIENTS AND METHODS

The French IBC patients had a lower educational level, a higher body mass index and a longer cumulative duration of breast-feeding, and they included a greater proportion of non-European women, than the non-IBC patients. In the multivariate analysis, only breast-feeding duration remained associated with the IBC status (P=10(-3)). These results could not be verified in the Tunisian series, because the duration of breast-feeding was unavailable in this center.

RESULTS

This study suggests that the etiology of IBC might be different of that of non-IBC.