A diagnosis of cancer and its subsequent treatment can be a very frightening and confusing experience for the pregnant patient, and are challenging for the physician and nurse. As women delay childbirth until later in life, the incidence of pregnancy associated with cancer is expected to increase. Currently, approximately 1 in 1,000 pregnancies is complicated by cancer.[1–5]
The tumors most commonly seen in women of childbearing age include cervical cancer, breast cancer, melanoma, lymphoma, and acute leukemia.[2–5] Today, many patients with these diagnoses choose to continue their pregnancies. Some patients may delay beginning treatment until after delivery, while others start treatment immediately. This decision depends on their diagnoses, stage of disease, and gestational age. Patients diagnosed late in their pregnancy may choose to deliver their babies early and then begin treatment immediately following delivery.
Patients treated while pregnant pose special challenges. When a cancer patient is pregnant, treatment decisions must take into account the welfare of the patient and the unborn baby. There is an obligation to do “good” for both mother and fetus.[1,6] This article provides an overview of cancer treatment during pregnancy and discusses current practice guidelines developed at our comprehensive cancer center, including the oncology nurse’s role in the care of these patients.
At our cancer center, to ensure continuity of care, a nurse from the Department of Gynecologic Oncology functions as a “nurse liaison” to assist our pregnant patients and their physicians. We have followed 89 pregnancies to date (4 women had 2 pregnancies since their cancer diagnosis). Figure 1 shows the distribution of disease types in a pregnant population at our cancer center between 2003 and April 2008. Figure 2 shows the outcome of pregnancies of patients who were
enrolled and followed in our data-collection study.
Anatomical and Physiological Changes During Pregnancy
Caring for a pregnant patient with cancer must take into account both anatomical and physiological changes occurring during pregnancy and risks associated with cancer diagnosis and treatment.
Maternal blood volume increases by about 40%–50% during pregnancy. Other hemodynamic changes include increases in cardiac output, systemic blood pressure, pulmonary vascular resistance, heart rate, and blood flow distribution. Coagulation properties change during pregnancy, resulting in an increased risk of pulmonary embolus and deep venous thrombosis.[7–9]
As the gravid uterus grows, anatomical changes occur. The diaphragm and abdominal organs are pushed upward. The heart changes in position, appearance, and function, and the heart rate increases and peaks in the third trimester. Respiratory and gastric functions may be altered.[7,8,10] Positioning the patient on her left side during the late stages of pregnancy ensures good circulation. When the mother is supine for long periods of time, the gravid uterus can compress the inferior vena cava and compromise circulation.[7–9]
Pregnancy Assessment in the Newly Diagnosed Patient
It is important to ask any female patient of childbearing age the date of her last menstrual period, before administering chemotherapy or performing any test with radiation. This provides an opportune moment to teach the patient the importance of contraception during cancer treatment. If pregnancy is suspected, but not certain, a serum pregnancy test should be done. In a normal pregnancy, the level of beta HCG (human chorionic gonadotropin) increases by 66% every 48 hours beginning at the time of implantation of the fertilized ovum. The first trimester is a period of organogenesis. Fetal exposure to chemotherapy agents in the first trimester may cause spontaneous abortion or congenital malformation.
It is important to ask the patient about her desires for the pregnancy. If she is not certain and/or needs counseling, she may be referred to a gynecologist for consultation. The physician can review the impact of cancer treatment relative to gestational age and address questions or concerns. Some patients are quite clear as to what they want to do. For others, the decision is more difficult and more information is needed.
Figure 1: Cancer During Pregnancy—Distribution of disease types in the pregnant population at M.D. Anderson Cancer Center between 2003 and 2007. Data represent 89 pregnancies in 85 women.
As with any cancer patient, early diagnosis and treatment offer the best prognosis. Regardless of cancer stage at diagnosis, pregnant patients with cancer do not appear to have a more aggressive clinical course, and the biological behavior of the cancer appears not to be influenced by the pregnancy. Outcomes are similar in pregnant vs nonpregnant women with cancer.