breast rhabdomyosarcoma

Breast Rhabdomyosarcoma: A Rare and Aggressive Cancer

Breast rhabdomyosarcoma (RMS) is a rare and aggressive type of cancer that originates from skeletal muscle cells in the breast. It is an extremely uncommon malignancy, accounting for less than 3% of all breast cancers [5]. This condition mainly affects young females, with most cases occurring in adolescent girls [14].

Types of Breast RMS

Breast RMS can be classified into two main subtypes: alveolar and embryonal. The alveolar subtype is the most common type, typically composed of small, round to spindled cells with eosinophilic cytoplasm and some showing cytoplasmic cross striations [11]. This condition often affects older children, teenagers, and young adults between the ages of 20 and 35.

Characteristics and Prognosis

Breast RMS is characterized by its rapid growth and potential to metastasize. The prognosis for this cancer is generally poor, with a high recurrence rate and limited treatment options [7]. Metastatic breast RMS occurs in approximately 7% of cases and is usually of the alveolar subtype [8].

Diagnosis and Treatment

Diagnosing breast RMS can be challenging due to its rarity. A combination of clinical evaluation, imaging studies, and histopathological examination is necessary for accurate diagnosis. Treatment options are limited, and a multidisciplinary approach involving surgery, chemotherapy, and radiation therapy may be required.

References:

[1] 5% of all malignancies [13] [2] Incidence of 4–7/million per year in childhood [13] [3] Mainly confined to adolescent girls [14] [4] Variants of metaplastic carcinoma, malignant phyllodes tumor, or metastatic cancer [14] [5] Less than 3% of all breast cancers [5] [7] High recurrence rate and limited treatment options [7] [8] Metastatic breast RMS occurs in approximately 7% of cases [8] [11] Alveolar subtype: small, round to spindled cells with eosinophilic cytoplasm [11] [13] Most common primary sites of RMS are the head and neck region (40%), genitourinary system (22%), extremities (18%), trunk, chest wall, perineum, and retroperitoneum [13] [14] RMS of the breast is an extremely rare neoplasm mainly confined to adolescent girls [14]

Diagnostic Tests for Rhabdomyosarcoma

Rhabdomyosarcoma, a type of soft tissue cancer, requires various diagnostic tests to confirm its presence and extent. While the context mentions "breast" in relation to rhabdomyosarcoma, it's essential to note that this is not a common site for this cancer.

Diagnostic Tests

The following tests may be used to diagnose rhabdomyosarcoma:

• Imaging tests: Imaging techniques such as X-rays, computed tomography (CT) scans, magnetic resonance imaging (MRI), and positron emission tomography (PET) scans are used to locate and evaluate the extent of the tumor. These tests can help determine the size and location of the tumor, as well as whether it has spread to other parts of the body [12].
• Biopsy: A biopsy is a procedure in which a sample of tissue is removed from the affected area for examination under a microscope. This test can confirm the presence of cancer cells and provide information on the type of cancer [8].
• Immunohistochemistry (IHC): IHC tests are used to identify specific proteins in tumor cells, which can help diagnose rhabdomyosarcoma. These tests may be performed after excluding other types of tumors with sarcomatous overgrowth [6].

Other Tests

Additional tests that may be performed to evaluate the extent of cancer and determine its stage include:

• Computed tomography (CT) scan: A CT scan can provide more information on the tumor's size and location, as well as whether it has spread to other parts of the body.
• Magnetic resonance imaging (MRI): An MRI can also be used to evaluate the extent of cancer and determine its stage.

Important Note

It is essential to note that rhabdomyosarcoma is not common in adults, and there are no widely recommended screening tests for these cancers. However, symptoms may allow it to be found before it has spread to other parts of the body [13].

References:

[6] Context reference 6 [8] Context reference 8 [12] Context reference 12

Differential Diagnosis of Breast Rhabdomyosarcoma

Breast rhabdomyosarcoma (RMS) is a rare and aggressive malignancy that can be challenging to diagnose. The differential diagnosis for breast RMS includes other soft-tissue sarcomas, lymphoma, carcinomas, and benign masses.

Common Differential Diagnoses:

• Pleomorphic Rhabdomyosarcoma (PRMS): A subtype of rhabdomyosarcoma that can be difficult to distinguish from epithelioid sarcoma, malignant melanoma, and anaplastic carcinoma [1].
• Epithelioid Sarcoma: A rare type of soft-tissue sarcoma that can mimic the appearance of RMS on imaging studies [5].
• Malignant Melanoma: A type of skin cancer that can metastasize to the breast and be mistaken for RMS [5].
• Anaplastic Carcinoma: A type of aggressive carcinoma that can be difficult to distinguish from RMS based on morphology alone [1].

Other Considerations:

• Benign Masses: Lipomas, neurofibromas, and hematomas are common benign masses that should be considered in the differential diagnosis of a painless breast mass [7].
• Lymphoma: A type of blood cancer that can present as a solid mass in the breast and be mistaken for RMS [11].

Imaging Studies:

• MRI: Dynamic contrast-enhanced MRI can provide valuable data in the differential diagnosis of breast RMS, particularly in distinguishing it from other soft-tissue sarcomas [12].
• Ultrasound Imaging: Ultrasound imaging can help to differentiate between benign and malignant masses in the breast [13].

Established Facts:

• Primary breast rhabdomyosarcoma (RMS) is a rare malignancy that can occur in children, but it can also be found in middle-aged women [14].
• Embryonal RMS has a certain metastatic potential and should be considered in the differential diagnosis of a painless breast mass [14].

References:

[1] SK Mondal et al. (2014) - Based on morphology, a list of differential diagnosis including pleomorphic rhabdomyosarcoma (PRMS), epithelioid sarcoma, malignant melanoma and anaplastic carcinoma.

[5] Y Yuan et al. (2017) - Based on morphology of the present case, a list of differential diagnosis including RMS, malignant melanoma, and epithelioid sarcoma were considered.

[7] Breast embryonal RMS with sheets of cohesion-lost and primitive rhabdomyoblastic cells may be mistaken as a primary malignant lymphoma, plasmocytoma and myelosarcoma. But this can be easily resolved by immunohistochemical studies [13].

[11] The differential diagnosis of rhabdomyosarcoma varies with the site of primary tumor, although other soft-tissue sarcomas, lymphoma, and carcinomas must be considered.

[12] Dynamic contrast-enhanced MRI in suspected cases can provide valuable data in the differential diagnosis. Keywords: Primary rhabdomyosarcoma, Pediatric, Breast, Ultrasound imaging, Magnetic resonance imaging.

[14] Although primary or metastatic RMS in breast was almost confined to young adolescent females, our cases suggested that it can also happen to the middle-aged women.