Mary McHugh, MD, a pathologist at Mount Carmel St. Ann's hospital in Westerville, Ohio, and a member of the College of American Pathologists, recommends finding out the following.
- What type of cancer is it? The most common form is IDC. Other common types include DCIS, ILC, and LCIS. Click here for a detailed explanation of each type.
- Is it invasive? Says Dr. McHugh: "If the cancer breaks through the wall of the breast duct, it's considered invasive. If it hasn't broken through, though, it's called in situ, or noninvasive cancer." Invasive cancer is more serious.
- What size is the tumor? This is measured in centimeters.
- What stage is it? Ductal carcinoma in situ (DCIS) is stage 0, the most curable; cancer that has spread to other parts of the body is stage IV.
- What is the histopathologic grade? This is a total score combining three different characteristics of the tumor as it appears under the microscope. Scores range from 3 to 9; a higher score indicates more aggressive cancer. Your report will include a histopathologic grade of 1 if your combined score is 3 to 5; 2 if your score is 6 to 7; and 3 if the score is 8 to 9.
- After surgery: Are the margins clear (aka negative) or positive? The surgeon removing the tumor tries to take a rim of cancer-free tissue around the tumor. "We're trying to confirm that the surgeon got it all out," explains Dr. McHugh. If the margins are positive, that may mean scheduling more surgery to get the rest out.
- Do the lymph nodes or blood vessels show cancer?
- Is the cancer hormone receptive? "Some cancer cells have a higher number of hormone receptors in the nucleus and that can promote the growth of the cells," Dr. McHugh says. Your report will say you're ER-positive, or estrogen receptor-positive, and/or PR-positive, progesterone receptor-positive, or negative for one or both. This helps doctors determine if you're a candidate for hormone therapy, such as tamoxifen, which blocks these receptors and can slow down or stop the growth of tumors.
- What is the cancer's HER2/neu status? "If tumor cells are HER2-positive, it means they're associated with a more aggressive tumor," says Dr. McHugh. Your HER2/neu status tells your oncologist whether the drug Herceptin (trastuzumab), which targets the HER2 protein, should be part of your treatment plan.