A method of detecting at least one axillary sentinel lymph node using ultrasonography is described. The method comprises injecting an iron hydroxide compound into a patient at or near a suspected tumor site in the breast and waiting an amount of time required for the iron hydroxide compound to enter cells of the sentinel lymph node. The axillary area near the injection site may then be analyzed using ultrasonography to identify at least one sentinel lymph node. Once identified, a small sample of tissue from the identified sentinel lymph node may be taken for pathological analysis to aid in determination of the stage or extent of breast cancer.
