Outcomes of pregnant women with Gynecological And Breast Cancers

Abstract

General Aspects of Cancer and Pregnancy C ancer diagnosed during pregnancy is rare. The incidence is estimated to be 1 in 1000-1500 pregnancies. There is a rising trend for delaying first pregnancy in women, particularly in more developed countries and as the incidence of cancer increases with age, it is expected that there will be an increase in malignancies during pregnancy. An interesting Australian population-based cohort study published by Lee et al in 2012 found that only 14% of cases of malignancy in pregnancy were attributed to an increase in age. The commonest cancers that occur in pregnancy are breast cancer, cervical cancer, melanoma and haematological (leukemia and lymphoma) malignancies. While the exact mechanisms for this phenomenon are unknown, estrogen and progesterone are established mitogens for breast tissue. Several theories have been postulated about the effect of the unique hormonal milieu of pregnancy in promoting the expansion of malignant cells. Presentation The presenting symptoms of malignancy in pregnant patients are not different from those of non-pregnant patients but, due to the physiologic changes during pregnancy, these symptoms may be overlooked. Palpable breast lumps, nipple or vaginal discharge, fatigue, anemia, nausea, bone pain or rectal bleeding are often falsely attributed to gestation resulting in delayed diagnosis. As with any other patient, a detailed history and a thorough physical examination should be the basis for the diagnostic work-up in pregnant women. Biopsies or fine needle aspirations may be performed with limited risk for the fetus. The maternal risk for endoscopies, lumbar punctures and bone marrow aspirations is low and these procedures can be performed with cautious use of sedatives and analgesics. Minor or major operations may also be performed during pregnancy with a slight increased risk for fetal loss in the 1st trimester due to general anesthesia. Diagnostic Tools and Pregnancy During pregnancy, workup and staging procedures are often modified to minimize radiation exposure. Radiographs should be minimized and, when necessary, should be accompanied by fetal shielding. Radiation exposure limits vary between sources, but generally, less than 5 rad of cumulative dose is considered safe. Ultrasound is safe in all trimesters and is useful to evaluate the liver and the kidneys. Computed tomography (CT) should be avoided when possible because of the fact that it typically involves significant radiation exposure. When necessary, CT should be done without contrast. Magnetic resonance imaging (MRI) is thought to be safe after the first trimester. The effects of gadolinium on the fetus are poorly studied, and thus, its use should be avoided. Positron emission tomography scan and bone scans are high in radiation exposure but may be necessary. If performed in pregnancy, these studies should be performed with proper shielding, ample maternal hydration, and a lower dose of radioactive tracer. Treatment of Malignancy: Surgery, Chemotherapy, and Radiation Therapy. Although the management of malignancy in pregnancy is usually similar to management outside pregnancy, there are some gestation-specific considerations. Anticoagulation should be strongly considered given due to the increased risk for venous thromboembolism associated with both malignancy and pregnancy. If surgery is indicated, it should ideally be performed in the second trimester, avoiding organogenesis in the first trimester and concerns of caval compression in the third trimester. When maternal survival is not affected by postponing surgery until after delivery, such as in the case of some thyroid cancers, surgery should generally be deferred. Regional anesthesia is preferred over general anesthesia if possible, although general anesthesia is not thought to be teratogenic. Before 24 weeks, documentation of fetal heart tones before and after surgery should be performed; after 24 weeks, intraoperative monitoring should be considered when feasible. However, it is important to note that, on the basis of location of operative field, continuous intraoperative monitoring may not be possible. When this is the case, the obstetric provider and the surgeon should use clinical judgment as to if, when, and how frequently heart tones should be assessed. If changes in fetal heart tones are noted intraoperatively, maternal positioning in the left lateral tilt, optimizing maternal oxygenation, and ensuring adequate blood pressure may help improve fetal status.