We report a case of an aggressive invasive mole which had ruptured the uterus, but where the uterus was saved by conservative surgery and emergency chemotherapy. A 28-year-old woman underwent surgical evacuation of retained products of conception following diagnosis of incomplete miscarriage at eight weeks gestation in her first pregnancy. A large amount of tissue was obtained and sent for histological examination. 

Three weeks later she presented with severe abdominal pain, pallor and tachycardia. Pregnancy test was positive. Histology of the products of conception was not available. The patient’s condition deteriorated rapidly with a clinical picture of intra-peritoneal haemorrhage confirmed by ultrasound scan. A ruptured ectopic pregnancy was suspected. Resuscitation was initiated and an emergency laparotomy was performed. Haemoperitoneum of about 2 litres of fresh blood was found, with brisk bleeding from what appeared like a 3cm vascular laceration at the upper part of the anterior uterine wall. This was repaired with a number of figure of eight stitches and haemostasis could be achieved despite the fact that the tissues were extremely friable. The needle had to be passed at a distance from the abnormal myometrium to avoid causing further bleeding. 

The patient was transfused with four units of red cells. Serum beta-hCG level was 62,000u/L post operatively. Histology of the products obtained showed a complete mole, confirming the clinical impression of an invasive mole having perforated the myometrium.

Staging work up revealed pulmonary metastases. The patient was diagnosed as FIGO stage III gestational trophoblastic neoplasia and low risk according to WHO categorisation. Accordingly, she was commenced on single agent chemotherapy with high dose methotrexate and folinic acid rescue. At completion of chemotherapy serum beta-hCG had normalised and restaging CT scan showed complete resolution of lung metastases. Contraception was advised for 12 months from the completion of chemotherapy. Beta-hCG follow up was performed as advised by the Charing Cross guidelines. Having failed to conceive naturally after the stipulated period of contraception, the patient underwent IVF and a healthy baby was delivered by an elective caesarean at 38 weeks gestation.

Molar pregnancy, or hydatidiform mole, represents an aberration in the fertilisation process. The incidence is between 0.57 and 1.1 per 1,000 pregnancies among Caucasians and almost double in Asian populations.

A molar pregnancy is considered malignant when there is invasion of the myometrium and beyond, or if the beta-hCG levels following evacuation of the uterus rise or plateau in the absence of a new pregnancy. Gestational trophoblastic neoplasia occurs in 15-20% of complete moles compared to 1-4% of incomplete moles. Although molar pregnancy can be suspected on ultrasound examination or on inspection of the products of conception at the time of evacuation, only less than 50% of these abnormal pregnancies, even in specialised centres, are diagnosed accurately before histological analysis, which remains the gold standard.

There are reported cases^1,2 and series³ of aggressive, advanced un-evacuated molar pregnancies presenting as acute haemoperitoneum due to tumoural uterine perforation. In most cases hysterectomy was required.^1,2,3 We only found one case report similar to ours where acute uterine rupture occurred a few weeks after uterine evacuation.⁴ In this case also a hysterectomy was performed. Although the uterine repair we performed allowed temporary cessation of bleeding, the successful subsequent obstetrical outcome was only possible because the tumour responded well to chemotherapy which was started without delay.

References

1. Kumar S, Vimala N, Mittal S et al. Invasive mole presenting as acute haemoperitoneum. JK Sci. 2004; 6: 159-60
2. Mackenzie F, Mathers A, Kennedy J. Invasive hydatidiform mole presenting as an acute primary haemoperitoneum. Br J Obs  Gynecol, 1993 (Oct); 100: 953-954
3. Singh A, Ratnani R. Heterogenous presentation of chorioadenoma destruens. The Journal of Obstetrics and Gynaecology of India, Dec 2012; 62(SI): S71-S74
4. Bruner D, Prichard A, Clarke J. Uterine rupture due to invasive metastatic gestational trophoblastic neoplasm. West J Emer Med 2013 (Sept); 14(5): 444-447