How is invasive ductal carcinoma (IDC) diagnosed?

Invasive ductal carcinoma (IDC), also known as infiltrating ductal carcinoma, is cancer that begins growing in the breast duct and then invades the fatty tissue of the breast outside of the duct. IDC is the most common form of breast cancer, representing 80 percent of all breast cancer diagnoses.

To diagnose any breast abnormality, your doctor may perform any of the following tests:

• Clinical breast exam - In this exam, your doctor manually checks your breasts for changes or abnormalities.
• Mammogram - This is an image of the inside of your breast captured either on film like an X-ray or as a computerized digital image.
• Ultrasound - In a breast ultrasound, high frequency sound waves exposed to breast area produce pictures of the inside of the breast, similar to an X-ray. This allows your radiologist to distinguish between a solid mass (benign or malignant tumors) and a liquid mass (cyst).
• MRI - MRI stands for magnetic resonance imaging. An MRI uses a magnetic field and radio frequency waves to project a very detailed picture of the inside of your breast onto a computer.
• Biopsy - For a biopsy, your doctor removes tissue from the inside of your breast to examine under a microscope. There are a variety of methods your doctor can use to obtain this tissue sample.
• Pathology - After your doctor draws a sample of your affected breast tissue, a pathologist examines the tissue under a microscope, classifies your tissue sample, and makes make a diagnosis.
• Staging Workup - Breast cancer staging is a system that describes the size, growth and type of your tumor and location of the cancerous tumor cells.