The differential for a hypoehoic breast lesion can be (keeping in view your age) anything from being cancerous to benign.
Even dilatation of mammary ducts is probably just a function of your age however if you have breast pain and nipple discharge other possible cause may include Ductal ectasia.
It may also suggest slight possibility of a malignancy.
Even as you have history of breast cancer in other breast so there may be chance of malginancy in right breast.
So to be more precise, there is a definite need for further investigation, which can include an aspiration or FNAC along with a list of symptoms such as low grade fever, loss of appetite, weight loss, generalized aches and pains, examination that can include a look for any axillary lymph nodes which gives you exact diagnosis.
Your Biopsy report can help in rule out cancer.
Besides that certain blood tests can also be helpful starting with the basic ones as Blood Complete Picture to more advanced such as the CA 15-3 and CEA (others can include HER-2 and CA 27.29).
So you need to be seen by your doctor for a clinical corelation of your current condition and investigations findings for further evaluation and management.
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