Clinical presentation and long-term outcome of pure myoepithelial carcinoma of the breast

doi:10.1016/j.ejso.2004.01.002

European Journal of Surgical Oncology (EJSO)

Volume 30, Issue 4, May 2004, Pages 357-361

https://doi.org/10.1016/j.ejso.2004.01.002 Get rights and content

Abstract

Introduction. Pure myoepithelial carcinoma of the breast is a rare tumour of controversial histogenesis. Little is known about its natural history and long-term outcome following treatment.

Methods. All patients with pure myoepithelial carcinoma treated at our institution between 1970 and 2001 were studied with respect to pathological features, outcome and prognosis.

Results. Six patients were identified. The median age was 60 (40–66) years and median follow-up was 34.5 months (range 14–76) months. Four tumours were T1 and one was T2 (one tumour size unknown). There were two moderately differentiated and three well-differentiated tumours (grade could not be assessed in one patient). Oestrogen and progesterone receptor could be assessed in five patients and all were negative. Primary treatment was wide local excision with clear radial margins. Lymph node assessment was negative in all patients. One patient received adjuvant radiotherapy. Three patients developed local recurrence at 15, 38 and 50 months and two patients developed distant metastasis at 30 and 79 months. The local recurrences were treated by further excision but two patients developed distant metastasis at intervals of 15 and 26 months, respectively. Two patients have died of the disease and four remain well. The 2-year and 5-year survival was 88% (SE, 6) and 55% (SE, 16), respectively. Large tumour size is a prognostic indicator of poor outcome.

Conclusion. Pure myoepithelial carcinoma of the breast adopts an aggressive clinical course with an outcome comparable to poorly differentiated adenocarcinoma of the breast.

Introduction

Pure myoepithelial carcinoma of the breast is a rare condition of controversial histogenesis. They are composed purely of malignant myoepithelial cells, which are usually spindle-shaped but may occasionally be polygonal. Myoepithelial cells have the structural characteristics of both epithelial and smooth muscle cells; hence the term ‘myoepithelial’ is used to describe them. They are present as an interrupted layer in normal mammary glandular structures, situated between luminal ductal epithelial cells and basement membrane throughout the mammary ductal system. The observation that breast epithelium differentiates into myoepithelial and luminal cell types suggests the existence of a ‘reserve epithelial stem cell’ capable of multidirectional differentiation. The progenitor stem cell hypothesis remains in dispute, as stem cells have never been convincingly demonstrated. Reports of myoepithelial carcinoma in the current literature are restricted to case reports with emphasis on diagnosis and pathology.1., 2., 3., 4., 5., 6., 7., 8. We present a single institution retrospective analysis of the clinical presentation and outcome of patients with pure myoepithelial carcinoma of the breast. In this study, the term ‘myoepithelial carcinoma’ is used to indicate pure myoepithelial carcinoma of the breast composed purely of spindle myoepithelial cells.

Section snippets

Patients and methods

Patients with a diagnosis of myoepithelial carcinoma of the breast were identified from a database at the Royal Marsden Hospital between January 1970 and July 2001 with review of hospital records. All patients had mammography, breast ultrasound, chest X-ray and pre-operative tissue diagnosis confirmed by fine needle aspiration cytology and/or core biopsy.

One pathologist (N.N.) reviewed all archival material. Light microscopic and immunohistochemical methods were used for the diagnosis of

Results

A definitive diagnosis of myoepithelial carcinoma of the breast was made in six patients. The clinical and pathological features are outlined in Table 1. The median age at diagnosis was 60 (40–66) years. The presenting feature was a lump in all patients.

Mammography and ultrasound had intermediate features except for positive evidence of cancer in only one patient on mammography. Cytology was positive or suggestive of malignancy in three patients. Surgical margins were clear in all patients.

Discussion

Myoepithelial cells are involved in the pathogenesis of several types of lesions in the breast. These include multifocal myoepitheliomatosis, the rare mixed tumour or pleomorphic adenoma, adenoid cystic carcinoma, adenomyoepithelioma and myoepithelial carcinoma (malignant myoepithelioma). Myoepithelial carcinoma is the only lesion composed purely of myoepithelial cells. The rest of the lesions are composed of a dominant population of myoepithelial cells.

Adenomyoepitheliomas are low-grade

References (22)

N. Cartagena et al.
Clear cell myoepithelial neoplasm of the breast
Hum Pathol
(1988)
G. Bigotti et al.
Myoepithelioma of the breast: histologic, immunologic and electronmicroscopic appearances
J Surg Oncol
(1986)
M.H. Enghardt et al.
An epithelial and spindle cell breast tumour of myoepithelial origin: an immunohistochemical and ultrastructural study
Virchows Arch
(1989)
R.A. Erlandson et al.
Infiltrating myoepithelioma of the breast
Am J Surg Pathol
(1982)
W. Schurch et al.
Malignant myoepithelioma (myoepithelial carcinoma) of the breast; an ultrastructural and immunohistochemical study
Ultrastruct Pathol
(1985)
F.A. Tavassoli
Myoepithelial lesions of the breast. Myoepitheliosis, adenomyoepithelioma and myoepithelial carcinoma
Am J Surg Pathol
(1991)
P.S. Thorner et al.
Malignant myoepithelioma of the breast. An immunohistochemical study by light and electron microscopy
Cancer
(1986)
S.R. Lakhani et al.
Malignant myoepithelioma (myoepithelial carcinoma) of the breast: a detailed cytokeratin study
J Clin Pathol
(1995)
H.M. Cameron et al.
Leiomyosarcoma of the breast originating from myoepithelium
J Pathol
(1974)
L. Rode et al.
Case 6: a spindle cell breast lesion in a 54 year-old woman
Ultrastruct Pathol
(1986)

P. Brasseur et al.

Malignant myoepithelioma of the breast. Report of a case

J Belge Radiol

(1990)

Cited by (24)

Malignant myoepithelioma of the breast (MMB); An interesting case report with pathological, immunohistochemical findings and review of literature
2019, Human Pathology: Case Reports
Citation Excerpt :
A case series reported that the median 2- and 5-year overall survivals were 88% and 55%, respectively. This article also suggested that a tumor of more than 2 cm confers poor prognosis [9,14]. Patient presented with many adverse clinical features, including a large tumor, poor performance status, malnutrition, lactic acidosis, and pulmonary embolism.
Malignant myoepithelioma (MMB) of the breast is an extremely rare and aggressive malignant tumor. The biological behavior of such malignancy and treatment outcomes of patients has not been clearly determined.
MMB is morphologically difficult to be distinguished from benign spindle cell proliferations. Identification and further research on the genesis of these tumors could help to discover new molecular targets for its management.
We herein describe the pathological and immunohistochemical characteristics of a case of MMB in a 51 year-old woman to add to the previous data about biological behavior and management strategy of such a rare aggressive entity.
We have confirmed the diagnosis of our case using immunohistochemisrty because malignant cells revealed diffuse expression of P63, SMA and S-100 in addition to high Ki-67 labeling index.
MMB is extremely rare entity which showed be suspected during differential diagnosis of any malignant spindle cell tumor of the breast.
Atypical breasts cancers
2015, International Journal of Surgery Case Reports
Citation Excerpt :
These cancers have a tendency to metastasize to viscera's like lungs and brain [5,10] and are found to be aggressive in nature [7] despite this, the role of chemotherapy is controversial and there is no consensus of its use [8]. In a study by Behranwala et al. [11], the 2-year and 5-year survival was 88% and 55% respectively. A 69 year old lady who was identified through breast screening in December 2012 for a new stellate mass found in her left breast which appeared highly suspicious of cancer (M4).
With increasing incidence of breast cancers there are now a larger number of cases diagnosed with rare malignancies. These can be diagnostic dilemmas and management strategy can be different by various breast multi-disciplinary teams (MDT).
We aim to discuss the evidence-based approach for management of these atypical breast cancers which were identified in patients from a single breast screening unit.
Patient with unusual breast malignancies (all types except invasive ductal and lobular) treated under the care of a single surgeon were identified during the breast multi-disciplinary discussion from 2011 to 2015. The histology and management of these cases were reviewed and literature search of electronic databases via PubMed and the search engines Google/Google Scholar was performed. Emphasis on keywords based on the histology type was used to limit search. Search was focused on the diagnosis, management and prognosis of these unusual breast cancers.
This series aims to focus on the evidence-based management of these rare breast malignancies; the diagnosis of which is crucial as it affects the overall treatment and prognosis.
Malignant myoepithelial breast carcinoma: Diagnosis and therapeutic difficulties
2013, Gynecologie Obstetrique et Fertilite
Le myoépithéliome malin mammaire est une tumeur rare et agressive. De nombreuses récidives locales et à distance sont décrites. Cependant, l’attitude thérapeutique n’est pas codifiée. Nous rapportons le cas d’une patiente de 61 ans ayant présenté un myoépithéliome malin. Un traitement chirurgical conservateur a été entrepris. La patiente a présenté une récidive locale après trois ans de surveillance. Ce cas souligne les difficultés thérapeutiques rencontrées dans ce type de tumeur et l’importance d’un suivi régulier prolongé après le traitement initial.
Myoepithelial carcinoma of the breast is a rare and malignant tumor. Local recurrence and distant metastasis are common. Treatment is not consensual. Here, we report a case of a 61-year-old female who developed a myoepithelial carcinoma. Primary treatment was a local wide excision with clear pathological margins. Three years later, a local recurrence was treated by further wide excision. Neither recurrences nor distant metastasis were detected four years later. Regular following of patients with myoepithelial carcinoma is essential.
Extensive extranodal metastases of basal-like breast cancer with predominant myoepithelial spindle cell differentiation
2010, Pathology Research and Practice
A differentiation towards myoepithelial cells has been demonstrated in several types of lesions in the breast. These include multifocal myoepitheliomatosis, the rare mixed tumor or pleomorphic adenoma, adenoid cystic carcinoma, adenomyoepithelioma and myoepithelial carcinoma (malignant myoepithelioma). Myoepithelial carcinoma is the only lesion purely composed of myoepithelial cells. All these tumors are benign and/or of low-grade malignancy, with the exception of malignant myoepithelioma. In contrast to the statement of the current World Health Organization (WHO), recent studies have reported that regional and distant metastases may occur in about 50% of pure myoepithelial carcinomas. The presented case of a breast carcinoma with dominant myoepithelial/spindle cell differentiation in a 58-year-old woman is an excellent example to document the highly aggressive biological behavior of this tumor phenotype. Despite an extensive chemotherapy and radiotherapy, the tumor was rapidly progressive, forming a finally exulcerating local tumor relapse and widespread metastases to the myocardium, lungs, liver, kidneys and skin. Similarities in morphology and biological behavior compared to patients with “triple-negative” (hormone receptor and Her2) monophasic sarcomatoid carcinomas and pure spindle cell sarcomas are discussed.
The significance of focal myoepithelial cell layer disruptions in human breast tumor invasion: A paradigm shift from the "protease-centered" hypothesis
2004, Experimental Cell Research
Human breast epithelium and the stroma are separated by a layer of myoepithelial (ME) cells and basement membrane, whose disruption is a prerequisite for tumor invasion. The dissolution of the basement membrane is traditionally attributed primarily to an over-production of proteolytic enzymes by the tumor or the surrounding stromal cells. The results from matrix metalloproteinase inhibitor clinical trials, however, suggest that this “protease-centered” hypothesis is inadequate to completely reflect the molecular mechanisms of tumor invasion. The causes and signs of ME cell layer disruption are currently under-explored. Our studies revealed that a subset of pre- and micro-invasive tumors contained focal disruptions in the ME cell layers. These disruptions were associated with immunohistochemical and genetic alterations in the overlying tumor cells, including the loss of estrogen receptor expression, a higher frequency of loss of heterozygosity, and a higher expression of cell cycle, angiogenesis, and invasion-related genes. Focal ME layer disruptions were also associated with a higher rate of epithelial proliferation and leukocyte infiltration. We propose the novel hypothesis that a localized death of ME cells and immunoreactions that accompany an external environmental insult or internal genetic alterations are triggering factors for ME layer disruptions, basement membrane degradation, and subsequent tumor progression and invasion.
Myoepithelial carcinoma of the breast
2019, Revista de Senologia y Patologia Mamaria
El carcinoma mioepitelial de mama (o mioepitelioma maligno) es un tumor poco frecuente compuesto exclusivamente por células mioepiteliales malignas. Su diagnóstico supone un reto, y viene dado por los hallazgos anatomopatológicos apoyados por las técnicas de inmunohistoquímica. Presentamos un caso clínico y revisión bibliográfica.
Myoepithelial carcinoma of the breast (or malignant myoepithelioma) is a rare tumor composed exclusively of malignant myoepithelial cells. Its diagnosis is a challenge and is reached through pathological findings supported by immunohistochemical techniques. We present a case report and a review of the literature.

View all citing articles on Scopus

View full text

Clinical presentation and long-term outcome of pure myoepithelial carcinoma of the breast

Abstract

Introduction

Section snippets

Patients and methods

Results

Discussion

Hum Pathol

Myoepithelioma of the breast: histologic, immunologic and electronmicroscopic appearances

J Surg Oncol

An epithelial and spindle cell breast tumour of myoepithelial origin: an immunohistochemical and ultrastructural study

Virchows Arch

Infiltrating myoepithelioma of the breast

Am J Surg Pathol

Malignant myoepithelioma (myoepithelial carcinoma) of the breast; an ultrastructural and immunohistochemical study

Ultrastruct Pathol

Myoepithelial lesions of the breast. Myoepitheliosis, adenomyoepithelioma and myoepithelial carcinoma

Am J Surg Pathol

Malignant myoepithelioma of the breast. An immunohistochemical study by light and electron microscopy

Cancer

Malignant myoepithelioma (myoepithelial carcinoma) of the breast: a detailed cytokeratin study

J Clin Pathol

Leiomyosarcoma of the breast originating from myoepithelium

J Pathol

Case 6: a spindle cell breast lesion in a 54 year-old woman

Ultrastruct Pathol

Malignant myoepithelioma of the breast. Report of a case

J Belge Radiol