[Pheochromocytomas and paragangliomas in pregnancy: About four cases and key messages on management]

OBJECTIFS

The diagnosis of a pheochromocytoma or paraganglioma secreting during pregnancy is a rare and serious situation, involving maternal-fetal prognosis. The purpose of this case series is to discuss the management of these patients.

METHODS

This is a retrospective study of cases of pheochromocytoma (n=2) or paraganglioma (n=2) managed during pregnancy between 2013 and 2020 in one center (Lille, France).

RESULTS

We report four cases of patients with a diagnosis of pheochromocytoma or paraganglioma during pregnancy, at respectively 4, 28, 31 and 34 weeks of amenorrhea (AS). Their pregnancies were affected by a sudden onset of hypertension sometimes associated with headaches, sweating, and palpitations. All patients delivered by Caesarean section after calcium channel blocker impregnation, with a good outcome. Tumor removal took place at a distance from delivery for each patient.

CONCLUSIONS

The therapeutic strategy includes antihypertensive treatment with calcium channel blockers or alphablockers and surgical curative treatment linked to gestational age. Multidisciplinary management as well as early diagnosis can improve the maternal-fetal prognosis. The preferred way of delivery is Caesarean section, but vaginal delivery can also be considered. Removal should ideally take place at a distance from the birth. The analysis of these cases has led to the development of a protocol for monitoring and management of parturients with diagnosis of pheochromocytoma or paraganglioma during pregnancy.

Acute Stress Cardiomyopathy: Heart of pheochromocytoma

Stress cardiomyopathy (SCM) is a syndrome characterized by transient regional systolic dysfunction of the left ventricle in the absence of angiographic evidence of coronaropathy. This abnormality is associated with high levels of catecholamines. Stress cardiomyopathy is also called Takotsubo (TS) cardiomyopathy. Pheochromocytoma crisis can occur spontaneously or can be precipitated by manipulation of the tumor, trauma, certain medications or stress for example during non-adrenal surgery. The main drugs leading to pheochromocytoma crisis include D2 dopamine receptor antagonists, noncardioselective β-adrenergic receptor blockers, tricyclic antidepressants and related neurotransmitter uptake blockers, sympathomimetics, certain peptide and steroid hormones and several agents used during induction of anesthesia. Patients can develop symptoms of heart failure associated with tachyarrhythmia, cardiogenic shock with hypotension and collapse, or apparent acute coronary syndromes. This review describes pathophysiology, epidemiology, diagnosis criteria and management of SCM.

Adrenergic receptors and cardiovascular effects of catecholamines

Activation of the sympathetic nervous system is responsible for the body's "fight or flight" reaction. The physiological responses to the activation of the sympathetic nervous system and adrenal medulla are mediated through the action of the endogenous catecholamines norepinephrine (or noradrenaline) and epinephrine (or adrenaline) on adrenergic receptors. Adrenergic receptors belong to the superfamily of G protein-coupled receptors (GPCR). Adrenoceptors are divided into alpha1, alpha2, beta1, beta2 and beta3 receptors. Norepinephrine stimulates both subtypes of α receptors and β1 receptors. Epinephrine stimulates all subtypes ofα and β adrenoreceptors. α1 adrenergic receptors, coupled to stimulatory Gq proteins, activate the enzyme phospholipase C and are mainly found in the smooth muscle cells of blood vessels and urinary tract, where they induce constriction. α2 receptors are coupled to inhibitory Gi proteins, that inactivate adenylyl cyclase, decreasing cyclic adenosine monophosphate (AMP) production. They are mainly found in the central nervous system, where their activation results in a decreased arterial blood pressure. β1 adrenoreceptors predominate in the heart, activate the Gs-adenylyl cyclase -cAMP-protein kinase A signaling cascade, and induce positive inotropic and chronotropic effects. β2 adrenoreceptors are distributed extensively throughout the body, but are expressed predominantly in bronchial smooth muscle cells. β2 adrenergic receptors activate adenylyl cyclase, dilate blood vessels and bronchioles, relax the muscles of the uterus, bladder and gastrointestinal duct, and also decrease platelet aggregation and glycogenolysis. β3 receptors can couple interchangeably to both stimulating and inhibiting G proteins. They are abundantly expressed in white and brown adipose tissue, and increase fat oxidation, energy expenditure and insulin-mediated glucose uptake. This review details the regulation of cardiac and vascular function by adrenergic receptors.

Prevalence and progression of carbohydrate disorders in patients with pheochromocytoma/paraganglioma: retrospective single-center study

BACKGROUND

Carbohydrate disorders are the most frequent metabolic disorders, affecting a significant proportion of patients with pheochromocytoma.

OBJECTIVE

A retrospective study assessed the prevalence and progression of carbohydrate disorders in 204 patients (92 men, 112 women) with histologically proven pheochromocytoma diagnosed in a single specialized tertiary center during a 40-year period (1978-2017). One hundred were followed-up after tumor removal.

RESULTS

Carbohydrate disorders were diagnosed in 49.5% of cases: 30.4% with diabetes and, 19.1% prediabetes. Subjects with carbohydrate disorders had significantly greater age at diagnosis and higher 24-hour urine metanephrine and normetanephrine concentrations than those with normal glucose tolerance. One-third of patients with diabetes achieved good glycemic control under oral treatment (54% on metformin monotherapy). One-third of patients overall required preoperative insulin treatment. Postoperative follow-up (100 patients; 5-year mean duration) showed reduced prevalence of diabetes (13% vs. 33%; P=0.0007) and prediabetes (12% vs. 24%; P=0.027). Almost 60% of subjects initially diagnosed with carbohydrate disorders recovered normal glucose tolerance after surgery; these subjects had significantly higher preoperative urine metanephrine/normetanephrine levels than those with persistent diabetes/prediabetes. Correlation analysis revealed a moderate negative relationship between urine metanephrine/normetanephrine concentration and the outcome of the carbohydrate disorders (Spearmen's Rho=-0.507; P=0.013). There was no significant difference according to pre- or postoperative prevalence of obesity (15% vs. 16%; P=0.845) or dyslipidemia (46% vs. 39%; P=0.316).

CONCLUSIONS

Carbohydrate disorders affect approximately 50% of pheochromocytoma patients; 30% develop overt diabetes, which may be the only clinical manifestation in some rare cases. Pheochromocytoma-related diabetes is more likely to affect patients with predominant adrenaline secretion. It is often easy to control and usually requires oral antidiabetic treatment. Reversibility of carbohydrate disorders depend on severity, preoperative metanephrine level, age and weight.