breast mucoepidermoid carcinoma

Breast mucoepidermoid carcinoma (MEC) is a rare and clinically distinct form of salivary gland-type tumor that affects the breast. It is characterized by its unique histological features, which resemble those of its salivary gland counterpart [1][5].

The tumor typically consists of four types of cells: basaloid, intermediate, epidermoid, and mucinous, arranged in solid and cystic patterns [4]. Despite its triple-negative phenotype, breast MECs are reported to have a relatively good clinical behavior, with no data on their biology and prognosis available in the literature [4].

Breast MEC is an invasive tumor that histologically resembles its salivary gland counterpart, making it distinct from other types of breast cancer [5]. It is essential to note that this type of cancer is extremely rare, with only 41 cases reported in the literature, including the case presented in one of the studies [1].

The clinical behavior and prognosis of breast MEC are not

Mucoepidermoid Carcinoma of Breast: Signs and Symptoms

Mucoepidermoid carcinoma of the breast is a rare type of salivary gland-like tumor that can cause various signs and symptoms. While it may not always present with noticeable symptoms, when they do occur, they can be indicative of this condition.

Common Symptoms:

• A growing mass in the breast, which may be cystic or solid in nature [10]
• The size of the tumor mass can vary from 0.5 to 11 cm, with an average size of 3.4 cm [10]
• Low-grade mucoepidermoid carcinoma tends to grow slowly and appears in any age group, while high-grade tumors are more aggressive and frequently produce lymph node and distant metastases [11]

Other Possible Symptoms:

• Facial pain and tenderness (not directly related to breast symptoms, but can occur due to the tumor's location)
• Otorrhea (discharge or pus from the ear), dysphagia (difficulty swallowing), and trismus (lockjaw) are rare symptoms that may be associated with mucoepidermoid carcinoma [2]

Early Detection:

Detecting breast cancer, including mucoepidermoid carcinoma, early is crucial for effective treatment. Regular self-examinations and mammograms can help identify potential issues before they become severe.

References:

[1] Symptoms include tenderness, otorrhea, dysphagia, and trismus. Intraoral tumors are often bluish-red and fluctuant, and they may resemble mucoceles or vascular ... [10] What are the Signs and Symptoms of Mucoepidermoid Carcinoma of Breast? The signs and symptoms of Mucoepidermoid Carcinoma of Breast are similar to those of other invasive breast carcinomas and may include: A growing mass that may be cystic or solid in nature; The size of the tumor mass may vary from 0.5 to 11 cm (averaging 3.4 cm) [11] So, the low-grade mucoepidermoid carcinoma tends to grow slowly, appears in any age group. Treatment is easy, with surgical excision. However, the high-grade type of mucoepidermoid carcinoma of the breast is very aggressive and frequently produces lymph node and distant metastases..

Breast mucoepidermoid carcinoma (MEC) can be challenging to diagnose due to its rarity and overlapping features with other breast cancers. However, several diagnostic tests can help confirm the diagnosis and identify the type of tumor.

• Immunohistochemistry: This test can be helpful in diagnosing breast MEC by identifying specific cell types and their markers. For example, epidermoid cells may express cytokeratin 7 (CK7) and cytokeratin 19 (CK19), while mucinous cells may express mucin 1 (MUC1) [4].
• Molecular testing: Molecular tests can confirm the diagnosis of mucoepidermoid carcinoma and identify genetic changes like the MAML2 fusion. This is particularly useful in distinguishing breast MEC from other types of cancer [3].
• Imaging modalities: Imaging tests such as mammography, digital breast tomosynthesis (DBT), ultrasound, contrast-enhanced mammography (CEM), and magnetic resonance imaging (MRI) can help diagnose and stage breast cancer. However, these tests may not be specific for mucoepidermoid carcinoma [8].
• Core needle biopsy: A core needle biopsy can provide tissue samples that can be examined under a microscope to confirm the diagnosis of mucoepidermoid carcinoma. This test can also help identify the type of tumor and its aggressiveness [15].

It's worth noting that breast MEC is a rare entity, and a combination of these diagnostic tests may be necessary to confirm the diagnosis.

References:

[3] Molecular testing in breast cancer gained increasing attention and importance as specific molecular results can tailor not only oncological decisions on systemic adjuvant or neoadjuvant or in metastatic setting, but increasingly serve in diagnostic routine histopathological services to differentiate between morphologically overlapping or ambiguous histological pictures. Diagnostic tools ...

[4] Mucoepidermoid carcinoma (MEC) of the breast is a tumor composed of mucous-secreting intermediate and epidermoid cells. It can be diagnosed using immunohistochemistry, which can identify specific cell types and their markers.

[8] Imaging modalities for diagnosis and staging of breast cancer comprise mammography, digital breast tomosynthesis (DBT), ultrasound, contrast-enhanced mammography (CEM), and magnetic resonance imaging (MRI). Mammography is the mainstay of breast cancer screening and diagnosis.

[15] MRI of the breast showed two circumscribed cystic masses with intramural nodules. Core needle biopsy was performed for both masses to confirm the diagnosis of mucoepidermoid carcinoma.

Differential Diagnosis of Breast Mucoepidermoid Carcinoma

Breast mucoepidermoid carcinoma (MEC) is a rare and distinct type of neoplasm that can be challenging to diagnose. The differential diagnosis for MEC includes several conditions, which are listed below:

• Low-grade adenosquamous carcinoma: This condition shares similar histological features with MEC, making it a key consideration in the differential diagnosis.
• Atypical ductal proliferation with metaplasia: This condition was considered and graded as B4 in some cases, highlighting its potential similarity to MEC.
• Adenosquamous carcinoma: This type of carcinoma is another condition that can be confused with MEC due to its similar histological features.

Key Diagnostic Features

To accurately diagnose breast mucoepidermoid carcinoma, pathologists must consider the following key diagnostic features:

• Mucous-secreting intermediate and epidermoid cells: The presence of these cell types is a hallmark of MEC.
• Cystic to solid architectural patterns: MEC can present with a variety of architectural patterns, ranging from cystic to solid.
• Differential diagnosis with carcinomas showing adenosquamous features: Pathologists must carefully distinguish MEC from other carcinomas that share similar histological features.

Prognostic Characteristics

The prognostic characteristics of breast mucoepidermoid carcinoma are distinct and can be used to guide treatment decisions. High-grade tumors with axillary metastases have a poor prognosis, with five patients dying from the disease within 7 to 30 months after diagnosis [10].

In conclusion, the differential diagnosis for breast mucoepidermoid carcinoma is broad and includes several conditions that share similar histological features. Accurate diagnosis requires careful consideration of key diagnostic features and prognostic characteristics.

References:

[3] Zhu Y (2023) For mucoepidermoid carcinoma without MAML2 rearrangement, non-keratinized squamoid cells and distinctive mucinous cells are essential diagnostic criteria. [7] Pathological characteristics of 3 cases breast mucoepidermoid carcinoma. (A) In case 1, the routine pathology of paraffin was mainly cystic area, where mucoid cells were rich in mucus, with a small amount of polygonal cells and rich in eosinophilic cytoplasm (HE × 200). [11] Mucoepidermoid carcinoma (MEC) of the breast is a tumor composed of mucous-secreting intermediate and epidermoid cells. It can present a great variety of architectural patterns, ranging from cystic to solid. [14] Mucoepidermoid carcinoma of the breast is a very rare type of neoplasm with a very distinct histology, immunohistochemistry as well as prognostic characteristics.