Irregular 5mm nodule

I am 34 and received my first ultrasound and third mamogram (mammogram) today.  It has been two years.  I have some coarse calification on the right breast and a 5mm nodule (suspect fibroadenoma) in the same area of the right breast.  The main concern about the nodule is that the shap is irregular and was explained to have a tail.  I would like more insight as to the coorelation between irregular nodules and or confirmed irregular fibroadenoma's and carcinoma.  

[Cleveland Clinic]

Dear kw785, When determining suspicion of a finding certain features are looked at on an ultrasound and mammogram.  One of those features is the shape.  An irregular shape may be more concerning of a malignant abnormality but would need to be evaluated in context.  If malignancy is suspected the next step in evaluation would likely be biopsy.