Cancer during pregnancy is not very common but not rare. It effects 1 out of 1000 pregnancies .Cancer very rarely affects the baby directly but management of cancer during pregnancy can be challenging for the mother as well as for the doctor. So, the patient should be referred to the specialist who has experience dealing with pregnant women with cancer.
Types of cancer in pregnancy
The following cancers are common in young women so tend to co-exist with pregnancy-
Cancer of cervix
Non Hodgkin lymphoma
Gestational trophoblastic cancer
The prevalence of ovarian cancer during pregnancy is about 1 in every 20,000 deliveries. Breast cancer is the most common cancer during during pregnancy. Incidence is about 1 in 3000 pregnancies. As there are physiological changes in breast during pregnancy, pregnant women may have delay in diagnosing breast cancer during pregnancy.
Pregnancy may cause delay in diagnosis of cancer. This is because symptoms of cancer like bloating ,headaches, breast changes ,vomiting or rectal bleeding may mimic the normal changes of pregnancy. Sometimes pregnancy may unmask a pre-existing cancer because pap test done as a part of standard pregnancy care can detect cervical cancer and ultra sound examination done for the fetus can diagnose an abdominal or pelvic lump.
If cancer is suspected during pregnancy ,the treating doctor and the pregnant woman both are concerned about the diagnostic tests. The information on safety of specific tests should be given to the pregnant woman. Xrays are otherwise avoided in pregnancy ,if necessary, the radiologist may use lead shields that guard the abdomen and hence fetus of the radiation exposure.CT scans are very accurate to diagnose cancer.CT scan of head and chest are usually safe during pregnancy but of abdomen and pelvis should be done if absolutely necessary.MRI and ultrasound tests are generally considered safe during pregnancy.
Treatment is based on the stage of pregnancy. This requires multidisciplinary team of oncologist,radiologist and obstetrician. Goal of the treatment is to treat the mother without compromising the baby. Various treatment options are available in modern era:-
Surgery-It is the safest method to treat the cancer as it poses minimal risk to the growing baby inside.
Chemotherapy-It uses the cell destroying drugs to destroy the fast growing cancer cells.If given in first trimester of pregnancy there is increased risk of birth defects and pregnancy loss.In subsequent trimesters ,it can be given without any apparent risk to the fetus.Studies have shown that babies exposed to chemotherapy while in utero during late pregnancy don’t show any abnormalities after delivery but chemotherapy during this period may indirectly harm the baby because of the side effects to mother.
Radiation therapy can harm the fetus in all trimesters of pregnancy so,it is generally avoided during pregnancy.
Breastfeeding during chemotherapy
Women on chemotherapy after delivery are advised not to breastfeed their babies because drugs can get transferred to the baby through breast milk and can harm the baby.
Management of women with cancer may be highly challenging but women should not be penalised for getting pregnant.