Cancerous pregnancy: When the unimaginable happens

The complex dynamics that result in a normal pregnancy are extremely intricate. Very small errors in the ovum or in the sperm genetic material results in catastrophic outcomes. PHOTO | FOTOSEARCH

Tracy arrived at the emergency department past midnight on a cold, rainy September night. She was in bad shape.

Tracy’s woes started four months earlier when she developed pregnancy complications at 13 weeks. She started spotting one evening and went to see a doctor at the nearby hospital. She was examined and her cervix was found closed. The doctor, however, took note that her uterine size felt like she was already 16 weeks pregnant. She was put on progesterone supplementation and asked to come back the next morning for an ultrasound scan to assess the well-being of the pregnancy.

She was back at the same hospital at five in the morning with crampy, abdominal pain and vaginal bleeding. The doctor diagnosed her with an inevitable miscarriage and sent her to theatre for evacuation of the uterus, so as to stop the bleeding. By nine o’clock, she was back in her house having breakfast.

She mourned the loss of her pregnancy as any first time mother would, but she picked herself up and tried to move on. However, three weeks later, while at her office desk, she started bleeding. She assumed her periods were back, but when the bleeding got very heavy and the crampy, abdominal pain persisted, she went to a hospital near her office. The doctor ordered for an ultrasound that showed that her uterus still had remnants of her previous pregnancy, hence the bleeding. She was taken back to theatre for a repeat evacuation of the uterus and went home thinking that she was fine.

She was wrong.

CANCER TREATMENT

By the time she came to us, Tracy had undergone uterine evacuation five times without a proper diagnosis. With the history she provided, the heavy bleeding and anaemia, an ultrasound scan was urgently ordered, along with a blood test measuring her pregnancy hormone level. The scan showed she still had remnants of a pregnancy and multiple cysts in her ovaries.

Tracy was wheeled to the operating room for the sixth time for evacuation. A sample of the tissue drawn was taken to the lab and she was transfused four units of blood. She survived the ordeal, but the journey had just began.

The test results confirmed Tracy had choriocarcinoma. Her miscarriage had metamorphosed into pregnancy cancer! Even more distressing was that it was a high grade type. Tracy was confused, and rightfully so. She had never heard of such a thing. There was no time to wait. She needed immediate commencement of cancer treatment.

The complex dynamics that result in a normal pregnancy are extremely intricate. Very small errors in the ovum or in the sperm genetic material results in catastrophic outcomes. Choriocarcinoma belongs to a group of pregnancy-related complications termed Gestational Trophoblastic Disease. These conditions vary in severity and not all of them become cancerous.

The origin of these abnormalities is in the chromosomes of the ovum and sperm that form the pregnancy. The ovum may have no chromosome and the sperm has double the amount of chromosomes it should have. Alternatively, the ovum may be fertilised by two sperms.

The resultant pregnancy ends up with partial or complete absence of development of a foetus, but the placental part develops and is abnormal. Since the pregnancy is incompatible with life, the woman miscarries spontaneously. The placental tissue coming out is abnormal and looks like a bunch of grapes.

After the miscarriage, the abnormal placenta may persist and keeps regrowing, effectively becoming cancerous. While majority of the choriocarcinoma cases follow a miscarriage, a few may result from a normal pregnancy and even rarer, following an ectopic pregnancy.

As the abnormal tissue is placenta, it will manufacture the pregnancy hormone, human chorionic gonadotrophin (hCG). The larger the volume of abnormal placenta in the body, the higher the levels of the hCG hormone. This cancerous placenta spreads quite quickly outside the womb to the pelvic organs, lungs, liver and even to the brain.

LOST HAIR

Tracy was started on chemotherapy with close monitoring. We had high hopes that she would do well. She would come for her chemotherapy cycle every three weeks until all the monitoring parameters returned to normal. Thereafter, she would do an extra three cycles for good measure.

The treatment wasn’t kind to her slight frame. She would go through the harrowing nausea and vomiting especially on the first two days of the cycle. She lost her glorious mane of hair by the third cycle and learnt to spot the bald look bravely. On two occasions, she needed blood transfusion to keep her strong enough to tolerate the onslaught of the next round and once, she needed an extremely expensive shot to boost her white blood cells to levels high enough to permit safe administration of the drugs.

Tracy received a total of eight cycles before we were satisfied with her progress. She was sad that despite completing her treatment, she would still not be permitted to conceive for a further one year to allow for effective monitoring of the condition to ensure there were no relapses. She had to take contraceptive pills to prevent pregnancy.

The hCG hormone levels would be used for effective monitoring of her progress and would be expected to remain undetected at all times. This would then mean that in the event she got pregnant, the hCG hormone levels would rise and we would not be able to tell if this was a result of a normal pregnancy or a relapse of the cancer.

Tracy went on to do well and eventually managed to fulfil her longing to be a mother. She was dutifully monitored for the first year after delivery to ensure the choriocarcinoma did not recur. She will always carry a high risk of the monster creeping back unannounced, but for now, she is braving the motherhood experience like a champion.

Dr Bosire is an obstetrician/gynaecologist