Pure apocrine carcinoma of the breast

Pure Apocrine Carcinoma of the Breast is a rare subtype of breast cancer characterized by the exclusive presence of apocrine cells. These cells are a type of epithelial cell that is found in various glands, including some of the sweat glands of the skin, and are known for their role in secreting substances by a process known as apocrine secretion. This form of breast cancer is distinct in its cellular makeup, clinical presentation, and potentially its response to treatment.

Epidemiology

Pure apocrine carcinoma is considered a rare entity, accounting for less than 1% of all breast cancers. It tends to occur more frequently in postmenopausal women, although cases have been reported across a wide age range.

Pathophysiology

The hallmark of pure apocrine carcinoma is the predominance of apocrine cells within the tumor. These cells are larger than typical breast cancer cells, with abundant eosinophilic cytoplasm and prominent nucleoli. The exact cause of apocrine differentiation in breast carcinoma is not fully understood, but it is thought to involve hormonal influences, particularly androgen receptors, which are often found to be overexpressed in these tumors.

Clinical Presentation

Patients with pure apocrine carcinoma of the breast may present with a palpable mass, breast pain, or changes in the skin overlying the breast, similar to other forms of breast cancer. However, due to its rarity, there may be a delay in diagnosis or it may be incidentally discovered during routine mammography.

Diagnosis

Diagnosis of pure apocrine carcinoma is made through a combination of imaging studies, such as mammography and ultrasound, followed by a biopsy of the tumor. Histological examination of the biopsy specimen, showing the characteristic apocrine cells, confirms the diagnosis. Immunohistochemistry may also be used to identify the expression of androgen receptors, which supports the diagnosis.

Treatment

The treatment of pure apocrine carcinoma generally follows the guidelines for other types of invasive breast cancer, including surgery (lumpectomy or mastectomy), radiation therapy, and possibly chemotherapy. Given the frequent expression of androgen receptors, anti-androgen therapy may also be considered, although more research is needed to establish its efficacy.

Prognosis

The prognosis for pure apocrine carcinoma of the breast is similar to that of other breast cancers when matched for stage and grade. However, due to its rarity, there is limited data on long-term outcomes. Early detection and treatment are critical for improving prognosis.

Conclusion

Pure apocrine carcinoma of the breast is a rare and distinct subtype of breast cancer. Due to its unique cellular characteristics and potential hormonal influences, further research is needed to better understand its pathophysiology and to optimize treatment strategies.

NIH genetic and rare disease info

• NIH info on Pure apocrine carcinoma of the breast

Pure apocrine carcinoma of the breast is a rare disease.