Poster Presentation Society of Obstetric Medicine of Australia and New Zealand ASM 2015

A Tale of Two Paragangliomas in Pregnancy (#103)

Jessie Teng 1 , Jennifer Conn 1 , Rebecca Szabo 2 , Stephanie Johnston 2 , Julia Unterscheider 2 , Sarah Peek 2 , Joe Novella 3 , Nicholas Jansen 3 , Adele MacMillan 3 , Alison Nankervis 1
  1. Diabetes and Endocrinology Unit, The Royal Women's Hospital, Melbourne, Australia
  2. Obstetric Unit, The Royal Women's Hospital, Melbourne
  3. Anaesthetics Unit, The Royal Women's Hospital, Melbourne

Case #1
A 15-year old woman (G1P0) presented at 23 weeks gestation with a blood pressure (BP) of 185/85mmHg. Secondary screen revealed plasma normetanephrines of 7196pmol/L (normal <900pmol/L) and a 5.3cm left infrarenal mass, consistent with a paraganglioma. She was commenced on alpha-blockade with prazosin, and later phenoxybenzamine. Propranolol was added for reflex tachycardia and insulin therapy for gestational diabetes. Surgical resection of the paraganglioma during pregnancy was deemed not feasible, due to its location directly behind the uterus. She developed episodes of chest discomfort, headaches and back pain with labile BP, prompting the decision for earlier delivery at 31 weeks gestation. She underwent planned Caesarean section, with combined spinal-epidural anaesthesia and intravenous magnesium sulphate (MgSo4) infusion. A 1.9kg female baby was delivered, requiring NICU support for prematurity. The patient underwent successful surgical resection of the paraganglioma at 6 weeks post-partum.

Case #2
A 32 year-old woman (G5P3M1) with bony metastatic noradrenaline- and dopamine-secreting paraganglioma was referred for antenatal care. She had two normal vaginal deliveries prior to her paraganglioma diagnosis, one termination whilst undergoing radiotherapy, and a miscarriage. The patient declined a termination for the current pregnancy. She remained asymptomatic with low BP readings despite plasma metanephrine levels at 9x upper limit of normal range. At 37 weeks gestation, she was admitted for medical optimisation prior to Caesarean section. Low-dose phenoxybenzamine (10mg) and prazosin (0.5mg) caused significant hypotension, despite concomitant boluses of intravenous fluids. She was commenced on intravenous MgSo4 and labetalol infusions peri-operatively, and delivered a healthy baby girl. Notably, she was hypertensive post-partum and tolerated phenoxybenzamine. She is currently awaiting peptide receptor radionuclide therapy (PRRT) for the bony metastases.

Key points:
 Management of a pregnant woman with paraganglioma requires multidisciplinary care, including obstetrics, endocrinology, endocrine surgery, anaesthetics, paediatrics and critical care, to determine optimal timing and mode of delivery
 Alpha-blockade can be challenging due to cardiovascular changes in pregnancy and concerns regarding placental blood flow.