Cancer Genetics for Nurses: Connecting the Dots

The traditional family history taken in a practice setting typically includes information from first-degree relatives (the immediate family and grandparents) to create a pedigree diagram; it can also include second- and third-degree relatives. This information can be used to generate meticulous diagrams that are helpful when discussing surveillance beyond the established guidelines.

The word “genetics” induces terror in the minds of many nurses. Although most student nurses received little information during their basic nursing education, the “genetic revolution” has made genetics a fundamental element of nursing practice. For many years, genetic information has been considered as “need to know” facts for prenatal nurses providing counseling to older mothers or pediatric nurses working with children diagnosed with rare, inherited disorders, but only as “nice to know” details for those in other specialties. Since the human genome was sequenced in 2003, new genetic information about inheritance and how altered genes impact multiple diseases is available almost on a daily basis. Oncology nurses know that genetic changes create cancer, but now these changes are recognized to affect the early detection, diagnosis, and treatment of malignancies. Pharmacogenomics is a new frontier allowing specific medical treatments to be designed with individual patients in mind (ie, personalized medicine). Connecting the dots in a family history can also help highlight the risk for inherited cancers and opportunities for prevention and careful surveillance.

Family history

The US Surgeon General’s Family Health Initiative was launched to encourage families to discuss their health issues and develop a family pedigree. Its site is also useful for nurses to use in a clinical setting or at a community screening.

A careful discussion of all cancers in the extended family should take place. If a patient talks about the occurrence of “female, liver, or brain cancers,” it is important to request more details. For example, a “female cancer” might be a colon cancer instead of an ovarian cancer, considering the incidence of each type. In addition, a liver cancer could be a colon cancer that has metastasized to the liver. These differences have important ramifi cations when considering genetic testing and plans for surveillance and prevention.

Once the maternal side, paternal side, and at least three generations of family members are accounted for and all of the dots and lines are connected, it can be simple to follow the visual identifi cation of health problems that move down and across generations. When drawing diagrams without the assistance of a website or computer program, the following factors should be noted:

• Squares are used to denote males and circles are used to denote females. In a relationship, the males are placed on the left, and a line connects the two figures at the center point.

• Children are denoted as a perpendicular line coming from the “male and female relationship.” If more than one child was born, they are connected as a parallel line with the parents, connecting with a perpendicular line to show descendants.

• A line crossing through the circle or square designates someone that is deceased. The cause of and age at death should also be included.

• Coloring or drawing patterns in the figures will allow for easier identifi cation of different diseases.

• More detail can be added to clarify types of cancers, age at diagnosis, age of the individual, birth order, and other information like consanguinity. Visit http://tinyurl.com/4ugofc to learn more about pedigree construction.

Several websites are available to assist oncology nurses with patient education on inherited cancers, and help identify who should be tested, what a positive test means, and what screening and surveillance guidelines should be implemented. The Genetics Education Center of the University of Kansas Medical Center is one such website. The National Comprehensive Cancer Network has also created guidelines for detection, prevention, and risk reduction of some inherited cancers.

Translating beyond the bedside

Another use of the pedigree was put into practice at a community screening for breast and cervical cancer. This study, Genetic Assessment Tool for Health Evaluation of Risk (GATHER), focused on the use of a pedigree. Because student nurses are required to learn about the importance of collecting genetic family histories in the pedigree format but rarely see the technique used in the practice setting, a group of students wanted to evaluate whether this tool could be applied in a clinical setting to identify persons at risk for developing cancer. In a clinical setting, time allotted for assessing family history is limited. The goal of this study was to determine a systematic, 10-minute method for incorporating the pedigree to help identify patients who are at an increased risk. Data was collected during a community screening for breast and cervical cancers using a mobile van. Study participants were interviewed for 10 minutes, and a pedigree diagram was developed, which was then compared to the medical history found in the participant’s chart. The results were statistically signifi cant, indicating that the pedigree technique could help identify more families at risk for cancer than the traditional medical history method. Participants also noted how much more impact “seeing” their risk had over only talking about “who had what illness” in their immediate family.

A visual tool

Because oncology nurses are in frequent, close communication with their cancer patients and family, this connection can generate meticulous diagrams that are helpful when discussing surveillance beyond the established guidelines. For example, a woman with a family history of breast cancer and thyroid problems knows how important it is to have a regular mammography starting at age 40 years, but a woman showing characteristics of Cowden’s Syndrome should also be monitored for endometrial cancer, receive renal cancer screenings, and undergo a baseline thyroid ultrasound at age 18 years with consideration of making it an annual procedure, especially if there is a family history of the syndrome. Another woman with a pre-menopausal family history of breast cancer and fi rst-degree relatives with brain tumors at an early age might have inherited Li-Fraumeni Syndrome. If confi rmed with genetic testing for a deleterious mutation of the p53 gene, she and other members of her family should undergo MRI screening, in addition to mammography starting as early as age 20 years, with a colonoscopy screening occurring by at least age 25 years.

A nurse educated before the genomic revolution may view this “new” information as intimidating, but patients and their families are beginning to ask for more answers. Using a pedigree in the clinical setting can help oncology nurses and other specialty nurses identify diseases that are known to have a genetic connection with detection, prevention, and riskreduction opportunities. Formal and informal education about genetics can enhance a nurse’s interactions with his or her patients. It is important that all oncology nurses take advantage of the educational opportunities available to learn about genetics.

Julie Eggert is an associate professor and the Healthcare Genetics Doctoral Program Coordinator at the Clemson University School of Nursing. She is also involved in the Cancer Risk Screening Program (CRiSP) at Bon Secours St. Francis Hospital-Eastside in Greenville, SC.