Dear Cookie77: The fibroglandular (or parenchymal) layer of breast tissue is located between the subcutaneous fat (fat just under the skin) and retromammary (behind the breast) layers. The parenchymal layer consists of the ducts and alveoli,
including the intralobular connective tissue (these are the "functional" parts of the breast). In the young nonlactating breast (a breast that is not producing milk), the tissue is primarily composed of fibroglandular tissue with little or no subcutaneous fat. With increasing age and parity, fat is deposited in both the subcutaneous and retromammary layers. In other words, this is a description of normal
tissue.
The "nodules" will need further clarification from the
radiologist - these could appear benign or indeterminant (requiring more views - another more focused mammogram) to further define their significance.
in a word, it means "normal." Parenchyma is a bit hard to define (for me, anyway) but basically refers to the normal substance of any sort of tissue. Breast parenchyma, liver parenchyma, etc. is the background of all the sorts of normal structures you see under a microscope. Fibroglandular is what breast tissue is: a combination of glands and fibrous tissues. Normal.