Definition of Grade III Ductal Carcinoma

Depending on how they are classified, there are over 250 different types of cancer. Grade III ductal carcinoma is a specific cancer of the breast, arising from a tumor in a duct of the mammary gland.

Carcinoma

MedicineNet.com defines carcinoma as cancer that begins in the skin or in tissues that line or cover body organs.

Ductal Carcinoma

Ductal carcinoma is usually followed by the words, "in situ," Latin for "in the place." It is typically non-invasive, meaning it has not spread.

Grading vs. Staging

Tumors are often classified by a system of grading and staging. Grading refers to the appearance of the cancer cells under a microscope, while staging refers to the size and/or extent of the cancer.

Grade 3

The College of American Pathologists says that grade 3 tumors are the most aggressive, growing faster than grades 1 and 2. Grade 3 tumor cells, also called high-grade, look very abnormal under a microscope.

Grading Systems

The National Cancer Institute says that different cancers use different grading systems. Ductal carcinoma is graded using the Bloom-Richardson system, while other cancers, like prostate or kidney, use different systems.

References

• MedicineNet: Definition of Carcinoma
• National Cancer Institute: Ductal Carcinoma In Situ
• College of American Pathologists: Breast Cancer