Paget Disease of the Breast (Paget Disease of the Nipple)
A rare cancer in the skin of the nipple or in the skin closely surrounding the nipple that is usually, but not always, found with another breast cancer (ductal in situ carcinoma or invasive breast cancer). In these cases, the tumor grows from underneath the nipple and breaks out onto the surface of the nipple.
Palliative Therapy (Palliative Care, Palliation)
Treatment given to help relieve the symptoms and reduce the suffering caused by cancer or other life-threatening diseases. Palliative therapy may help a person feel more comfortable, but it does not treat or cure the disease. For example, surgery, radiation therapy, or chemotherapy may be given to remove, shrink, or slow the growth of a tumor that is causing pain. Palliative therapy may be given with other treatments from the time of diagnosis until the end of life. Also called palliative treatment.
Palpable
Describes a breast lump or abnormal area that can be felt during a clinical breast exam.
Palpation
To examine, using the hands and fingers.
Partial Mastectomy (see Lumpectomy in L)
Pathologic Complete Response
No signs of cancer found in tissue samples removed during surgery or biopsy after a cancer treatment (chemotherapy or radiation). A pathologist checks tissue samples under a microscope to see if there are any cancer cells left after treatment. Knowing if the cancer is in pathologic complete response may help show how well treatment is working or if the cancer will come back. Also called pathologic complete remission.
Pathologist
A doctor who uses a microscope to study the breast tissue and lymph nodes removed during biopsy or surgery and determines whether or not the cells contain cancer.
Peri-Menopause
The time in a woman’s life prior to menopause when menstrual periods become irregular and some menopausal symptoms may begin. This is usually 3 to 5 years before menopause.
Peripherally Inserted Central Catheter (PICC)
A small tube used to deliver medicine to the body through a vein. Instead of being reinserted for each use, a PICC is left in place to allow access for a long period of time (weeks to months).
Personalized Medicine
Using information about a person's genes or proteins, the tumor’s genes, and characteristics of the tumor to prevent, diagnose and treat disease. In cancer, personalized medicine uses specific information about a person’s tumor to help make a diagnosis, plan treatment, find out how well treatment is working, or make a prognosis. Examples of personalized medicine include using targeted therapies to treat specific types of cancer cells, such as HER2-positive breast cancer cells, or using tumor marker testing to help diagnose cancer. Also called precision medicine.
PET (Positron Emission Tomography)
PET scans usually use a form of radioactive sugar. Body cells take in different amounts of the sugar, depending on how fast they are growing. Cancer cells, which grow quickly, are more likely to take up larger amounts of the sugar than normal cells. You’ll be asked to not drink any sugary liquids for several hours before the test.
Pharmacogenomics (Pharmacogenetics)
The study of the way genes affect a person’s response to drugs to help predict which drugs may offer him/her the most benefit.
Phenotype
A characteristic in a person that results from the interaction between his/her genes and his/her environment. Some examples of a person’s phenotype are height, eye color, hair color, and blood type.
Phyllodes Tumor
A rare tumor that usually forms in the connective tissue of the breast. Phyllodes tumors tend to grow quickly and get large, but they rarely spread to other parts of the body. Most are benign (not cancer), but some may be malignant (cancer) or borderline (in between benign and malignant). Phyllodes tumors are usually removed by surgery, but they can come back. They are most common in women between 40 and 50 years of age. Also called CSP and cystosarcoma phyllodes of the breast.
Pituitary Gland
A part of the brain that controls growth and other glands in the body, such as the ovaries.
Placebo
An inactive medicine sometime used to have a comparison to a new drug in a clinical study. May be called a "sugar pill."
Positron Emission Tomography (see PET in P)
Postmenopausal Hormone Use (see Menopausal Hormone Therapy in M)
Precision Medicine
A form of medicine that uses information about a person’s genes, proteins, environment, and lifestyle to prevent, diagnose, or treat disease. In cancer, precision medicine uses specific information about a person’s tumor to help make a diagnosis, plan treatment, find out how well treatment is working, or make a prognosis. Precision medicine may also be used to help determine a person’s risk of developing certain types of cancer. Examples of precision medicine include using targeted therapies to treat specific types of cancer, such as HER2-positive breast cancer, or using tumor marker testing to help diagnose cancer. Precision medicine is sometimes called personalized medicine.
Predictive Factors
Factors (such as hormone receptor status) that help guide treatment for a specific cancer case. Predictive factors can be used to help predict whether a person’s cancer will respond to a specific treatment. A predictive factor can also be something that increases a person's risk of developing a disease or condition.
Predispose
To make more at risk for a disease. For example, people with certain mutations (changes) in their genes or a family history are more likely to get certain types of cancer.
Premenopausal Women
Women who have regular menstrual periods.
Preoperative Chemotherapy (see Neoadjuvant Chemotherapy in N)
Prevention
Steps taken to lower the risk of a disease. For example, lifestyle changes, such as quitting smoking, lowers the number of people who will get lung and other cancers.
Primary Chemotherapy (see Neoadjuvant Chemotherapy in N)
Primary Tumor
The original cancer.
Progesterone
A female sex hormone made by the body that is important in menstrual cycles and pregnancy. May be made in a laboratory (called progestin) and used in birth control pills, menopausal hormone therapy and other types of hormone treatment.
Progesterone Receptor
Specific proteins on cells that progesterone hormones attach to. A high number of progesterone receptors on a breast cancer cell often means the cancer cell needs progesterone to grow.
Progestin
Any substance (laboratory-made or natural) that has some or all of the effects of progesterone (a female sex hormone) in the body.
Prognosis
The likely outcome or course of a disease; the chance of recovery or recurrence.
Prognostic Factors
Factors (such as tumor type, size and grade) or a patient’s characteristics that can be used to estimate the chance of recovery from cancer.
Progression
The growth or spread of cancer, with or without treatment.
Progression-Free Survival
The length of time a person lives with cancer (such as metastatic breast cancer) before the cancer grows or spreads.
Prophylactic Mastectomy
Preventive surgery where one or both breasts are removed in order to prevent breast cancer. When both breasts are removed, the procedure is called bilateral prophylactic mastectomy.
Prosthetic (Breast Prosthetic, Prosthesis)
An artificial breast form that can be worn under clothing after a mastectomy.
Punch Biopsy
A procedure in which a small round piece of tissue about the size of a pencil eraser is removed from a patient using a sharp, hollow, circular instrument. The tissue is then checked under a microscope for signs of disease. A punch biopsy may be used to check for certain types of cancer, including skin, vulvar, and cervical cancer. It may also be used to check for certain skin conditions and changes that may lead to cancer.