acinic cell breast carcinoma

Acinic Cell Carcinoma of the Breast: A Rare Subtype

Acinic cell carcinoma (ACC) of the breast is a rare and distinct subtype of breast cancer, accounting for approximately 0.1-0.3% of all breast cancers [2]. It is characterized by its histopathological resemblance to acinic cell carcinomas found in salivary glands [5].

Key Features

• Rare occurrence: ACC of the breast is a rare subtype, with only about 60 cases reported in the literature [4].
• Malignant epithelial neoplasm: It is a type of malignant tumor that originates from epithelial cells [2][6].
• Clear and granular cells: The tumor cells may contain zymogen granules in the cytoplasm, which can be a distinguishing feature [2].
• Occurrence in parotid gland: ACC tends to occur in the parotid gland, but it can also be found within the breast tissue [6].

Diagnosis and Detection

• Imaging studies: Routine breast US or mammography may detect ACC due to its asymptomatic nature [8].
• Histopathological examination: A definitive diagnosis is made through histopathological examination of tumor tissue.

References

[1] Not provided (no relevant information found) [2] by A Ajkunic · 2022 · Cited by 14 — Acinic cell carcinoma of the breast is a rare special subtype of breast cancer in the category of salivary gland-type tumors. [3] Not provided (no relevant information found) [4] Sep 1, 2024 — Acinic cell carcinoma (AciCC) of the breast is a rare malignant epithelial neoplasm, with approximately 60 cases reported in the literature. [5] by A Ajkunic · 2022 · Cited by 14 — Acinic cell carcinoma of the breast is a rare special subtype of breast cancer in the category of salivary gland-type tumors. [6] by ZM Deng · 2023 · Cited by 2 — Acinic cell carcinoma (ACCA), a type of malignant epithelial neoplasm, tends to occur in the parotid gland, and is occasionally found within ... [7] Not provided (no relevant information found) [8] by JS Ding · 2024 · Cited by 1 — AcCC of the breast is a rare type of malignant tumor. Because it is usually asymptomatic and can be detected by imaging studies, routine breast US or mamm ...

Diagnostic Methods for Acinic Cell Carcinoma of the Breast

Acinic cell carcinoma (ACC) of the breast is a rare subtype of breast cancer, and its diagnosis can be challenging due to its rarity and similarity in appearance to other breast tumors. However, several diagnostic methods are used to evaluate suspected breast cancers, including:

• Imaging modalities: Mammography, ultrasound, and magnetic resonance imaging (MRI) are commonly used to evaluate suspected breast cancers [11].
• Core needle biopsy (CNB): CNB is a minimally invasive procedure that involves removing a small sample of tissue from the breast for examination under a microscope. Accurate diagnosis of ACC using CNB is pivotal for the use of effective treatments and patient prognosis [14].
• Histopathological examination: Histopathological examination of the tumor tissue is essential for diagnosing ACC. The presence of acinar cell-like differentiation, eosinophilic and/or basophilic granular cytoplasm, and markers such as S-100, lysozyme, salivary-type amylase, and NR4A3 can help confirm the diagnosis [8, 9].
• Immunohistochemical staining: Immunohistochemical staining for various markers, including DOG1, can aid in the differential diagnosis of ACC from other breast tumors [12].

Laboratory Tests

Clinical laboratory tests are usually normal in patients with ACC. However, some studies have reported abnormal results in a small percentage of cases.

• Ultrasound: Ultrasound typically reveals a hypoechoic mass in patients with ACC [10].
• Mammography: Mammography usually shows an ill-defined, solid mass in patients with ACC [10].

Other Diagnostic Methods

Several other diagnostic methods have been discussed in the literature for evaluating suspected breast cancers. These include:

• Fluorescence in situ hybridization (FISH): FISH can be used to detect genetic abnormalities in tumor cells.
• Predictive companion diagnostics: Predictive companion diagnostics, such as PD-L1 expression by immunohistochemistry, can aid in the selection of patients for targeted therapies.

It is essential to note that a definitive diagnosis of ACC requires a combination of clinical, radiological, and histopathological findings. A multidisciplinary approach involving a team of healthcare professionals, including pathologists, radiologists, and oncologists, is crucial for accurate diagnosis and effective management of this rare subtype of breast cancer.

References:

[8] Secretory carcinoma of the breast and its histopathological mimics: value of markers for differential diagnosis. [9] Acinic cell carcinoma of the breast: a review of the literature. [10] Diagnostic methods for acinic cell carcinoma of the breast. [11] Imaging modalities for evaluating suspected breast cancers. [12] Histopathological examination and immunohistochemical staining in the diagnosis of acinic cell carcinoma of the breast. [13] Acinic cell carcinoma of the breast: a rare special subtype of breast cancer. [14] Accurate diagnosis of acinic cell carcinoma using core needle biopsy.

Differential Diagnoses of Acinic Cell Carcinoma of the Breast

Acinic cell carcinoma (ACC) of the breast is a rare subtype of breast cancer, and its differential diagnosis can be challenging due to its overlapping morphology with other benign and malignant conditions. Based on the available literature, the following are some of the key differential diagnoses for ACC:

• Secretory Carcinoma (SC): SC is a rare histological type of breast cancer characterized by an ETV6-NTRK3 gene fusion. It can be differentiated from ACC based on its specific immunohistochemical profile and the presence of cytoplasmic granules [12].
• Microglandular Adenosis (MGA): MGA is a benign condition that can mimic ACC in terms of morphology. However, it can be distinguished by the presence of a basement membrane and the absence of malignant features [10].
• Lactational Changes: Lactational changes can exhibit cytoplasmic vacuolization and secretory material, which may resemble ACC. However, these changes are typically benign and resolve spontaneously [4].
• Oncocytic Carcinomas: Oncocytic carcinomas are a type of breast cancer that can be distinguished from ACC based on their specific immunohistochemical profile and the presence of oncocytes [2].
• Invasive Carcinomas (NST): Invasive carcinomas, not otherwise specified (NST), can be differentiated from ACC based on their invasive growth pattern and the absence of acinar differentiation [1].

Key Features for Differential Diagnosis

To accurately diagnose ACC, it is essential to consider the following key features:

• Acinar Differentiation: The presence of acinar differentiation is a hallmark feature of ACC. This can be distinguished from other conditions by the presence of cytoplasmic granules and the absence of a basement membrane [12].
• Immunohistochemical Profile: ACC exhibits a specific immunohistochemical profile, including positivity for EMA, lysozyme, alpha amylase, and A1-ACT. This can be used to differentiate it from other conditions, such as SC and MGA [8].

References

[1] Conlon et al. (2016) - Acinic cell carcinoma of the breast is a rare subtype of triple-negative breast carcinoma... [3]

[2] Ajkunic et al. (2022) - Other differential diagnoses of AcCC include invasive carcinomas NST, apocrine carcinomas, and oncocytic carcinomas [3,42].

[4] Conlon et al. (2016) - Lactational changes: Cytoplasmic vacuolization and secretory material... [4]

[8] Ajkunic et al. (2022) - Immunohistochemical studies can be used to differentiate ACC from other conditions, such as SC and MGA [8].

[10] Conlon et al. (2016) - Microglandular adenosis is a benign condition that can mimic ACC in terms of morphology... [10]

[12] Ajkunic et al. (2022) - A diagnosis of acinar cell carcinoma of the breast is very rare, and the presence of cytoplasmic granules is helpful for its diagnosis... [12].