Just had mammogram and have a nodular density requiring further investigation. can this be cancer?

Maybe, maybe not: The annual mammogram is a screening procedure to try and find women who may have a problem. Very often the second diagnostic step comes back without a diagnosis of cancer. The concern, of course, is that it could be cancer. That's why we do the screening. The hope is that any cancer will be found early and more easily treated.

Breast nodule: Yes. This is why you get the mammogram and why you need further investigation. Any cystic, nodular, or calcified lesion is potentially cancer until proven otherwise. The additional imaging or biopsy will determine the pathology.

Yes,: but at least 80% of mammo recalls turn out to be nothing of concern, and of the remainder that might go to biopsy, 70-80% of those turn out benign. The odds are strongly in your favor. It is common(approx 10% of the time) to get called back for additional imaging due to a questionable abnormality on screening.