The Role of Unenhanced Magnetic Resonance Imaging in Quantitative Assessment of Metastatic Involvement of Axillary Lymph Nodes in Patients With Breast Cancer: Observational Descriptive Study.

The presence of axillary metastasis is important for prognosis and determining of treatment plan, so identification of axillary metastasis in early stage newly diagnosed breast cancer is important for staging of disease and treatment. However, approximately 40% of women who presents with early stage breast cancer also have axillary metastasis.

The status of lymph nodes in patients with breast cancer used to be evaluated with axillary lymph node dissection. During the last 15 years, sentinel lymph node biopsy has replaced for grading of patients with clinically lymph node negative breast cancer. Despite being a less invasive method when compared to axillary lymph node dissection, sentinel lymph node biopsy also leads to complications such as lymphedema, seroma, localized swelling, pain, paresthesia, decrease in arm strength, infectious neuropathy and shoulder stiffness in 20% of patients.

The imaging modalities for assessing the axillary lymph nodes are rapidly evolving. Ultrasound is applied widely for its convincing and dynamic observation. However, the sensitivity and specificity of ultrasound for lymph node metastasis were unreliable and controversial.

Owing to radiation and relative lower diagnostic accuracy, computed tomography is limited in clinic.

Positron emission tomography and positron emission tomography/computed tomography can reflect metabolism of glycolytic activity. Undoubtedly, they have shown the higher diagnostic significance in assessing distant metastasis and regional metastatic axillary lymph nodes, but their high radiation and expensive fee keep the common people away. Ultrasmall super paramagnetic iron oxide is the same.