Any of the many neoplasms that affect reproductive-aged women can complicate pregnancy. Fortunately, most encountered neoplasms are benign, and uterine leiomyomas and ovarian cysts are the most frequent. Despite this, the incidence of malignancy approximates 1 case per 1000 to 2000 pregnancies (Korenaga, 2020; Ma, 2020). A third are diagnosed prenatally, and the remainder within 12 months of delivery. The distribution of some of these is shown in Figure 66-1 (de Haan, 2018). In another report from the Cancer Research Network, breast malignancies made up 25 percent and thyroid cancers, 20 percent. Melanoma and hematological and cervical cancers each contributed approximately 10 percent (Cottreau, 2019).
Distribution of cancer in 1170 pregnant women form the International Network on Cancer, Infertility, and Pregnancy (INCIP).
During pregnancy, cancer management poses unique problems related to fetal concerns, and treatment is individualized. Considerations include the type and stage of malignancy, the desire for pregnancy continuation, and inherent risks associated with modifying or delaying cancer treatment. Last, adverse pregnancy outcomes have been associated in general with gravidas with cancer (Ma, 2020; Momen, 2018).
CANCER THERAPY IN PREGNANCY
Operative procedures may be indicated to aid cancer diagnosis, staging, or therapy. Fortunately, most surgeries that do not interfere with the reproductive tract are well tolerated by both mother and fetus (Chap. 49, p. 867). Although many operations have classically been deferred until after 12 to 14 weeks’ gestation to minimize miscarriage risks, this probably is unnecessary. We believe that surgery should be performed at any gestational age if maternal well-being is imperiled.
Both pregnancy and malignancy are risk factors for venous thromboembolism (VTE). From studies of women with cancer during pregnancy, the risk of VTE is higher in pregnancy and in the postpartum period than in gravidas without a malignancy (Bleu, 2016; Greiber, 2021). Current guidelines lack specific recommendations for pregnant women undergoing surgeries for cancer. Thus, depending on the complexity of the planned procedure, it seems reasonable to consider prophylactic low-molecular-weight heparin combined with elastic stockings and/or intermittent pneumatic compression (Chap. 55, p. 989).
Sonography is a preferred imaging tool during pregnancy. Even so, the American College of Obstetricians and Gynecologists (2019c) notes that most diagnostic radiographic procedures deliver very low x-ray doses and should not be delayed if they would directly affect therapy (Chap. 49, p. 872). Magnetic resonance (MR) imaging can safely be performed in any trimester, but delay until after the first trimester may lower potential risks. Gadolinium should not be used in the first trimester and should be used later in pregnancy only when the benefits overwhelmingly outweigh risks (American College of Radiology, 2021; ...