SUN-510 - Persistent Metastatic Pheochromocytoma in Pregnancy

Background:
Pheochromocytoma in pregnancy is rare and associated with significant maternal and fetal morbidity, particularly when biochemically active. Most reported cases involve localized tumors; data guiding management of persistent metastatic disease during pregnancy remain limited.

Clinical

Case:
A 30-year-old G5P2032 with metastatic pheochromocytoma presented at 9 weeks’ gestation normotensive (BP 117/76 mmHg). She underwent left adrenalectomy in 2021 and developed metastatic recurrence in 2024 with residual disease in the liver, para-aortic nodes, sacrum, and left 6th rib following debulking surgery, radiation, and systemic chemotherapy (last dose 2 weeks post-LMP). Preconception PET showed mixed response. Genetic testing was negative, and she was not on antihypertensive therapy entering pregnancy.

At 16w4d (12/12/2025), she presented with hypertensive emergency (BP 165/122 mmHg) requiring ICU care. Pre-pregnancy biochemical testing (3/26/2025) demonstrated catecholamine excess (urine normetanephrine 922 µg/24 hr, urine norepinephrine 188 µg/24 hr, plasma metanephrines 3.9 nmol/L, plasma norepinephrine 10663 pg/mL). Repeat testing on 12/11/2025 remained elevated (plasma normetanephrine 1284.3 pg/mL, urine normetanephrine 2977 µg/24 hr, urine norepinephrine 825 µg/24 hr), with persistent abnormalities on 3/4/2026.

Doxazosin 2 mg twice daily improved BP control but was limited by orthostatic hypotension. At 26 weeks, BP again exceeded 140/90 mmHg, prompting titration to 4 mg twice daily. At 28 weeks, she re-presented with headache and decreased fetal movement; BP remained controlled (110–130s/60–80s) with reactive NST and negative preeclampsia evaluation. Serial fetal growth remained appropriate for gestational age without evidence of growth restriction (EFW 38th to 83rd percentile from 16–34 weeks).

At 34 weeks, she remains clinically stable under multidisciplinary care. Delivery planning includes scheduled cesarean delivery at 37 weeks under general anesthesia with invasive hemodynamic monitoring and continuation of alpha-blockade. Postpartum oncology follow-up is planned for further systemic therapy.

Conclusion:
Persistent metastatic pheochromocytoma in pregnancy produces ongoing hemodynamic instability despite prior therapy. Sustained biochemical activity and limited pregnancy-compatible treatments necessitate individualized alpha-blockade and coordinated multidisciplinary planning. Standardized management strategies remain lacking.

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