Expression of LHCGR (Luteinizing Hormone/Chorionic Gonadotrophin Receptor) in Pheochromocytomas Unveils an Endocrine Mechanism Connecting Pregnancy and Epinephrine Overproduction

Aberrant hormone receptors regulate a wide spectrum of endocrine tumors

Aberrant G-protein coupled receptor (GPCR) expression is highly prevalent in cortisol-secreting primary bilateral macronodular adrenal hyperplasia (PBMAH) and unilateral adenomas. The aberrant expression of diverse GPCRs and their ligands play an important role in the over-function of various endocrine tumours. Examples include aberrant expression of MC2R, 5-HT4R, AVPR1A, LHCGR, and GnRHR in primary aldosteronism; GCGR, LHCGR, and 5-HT4R in phaeochromocytomas and paragangliomas; TRHR, GnRHR, GIPR, and GRP101 in pituitary somatotroph tumours; AVPR2, D2DR, and SSTR5 in pituitary corticotroph tumours; GLP1R, GIPR, and somatostatin receptors in medullary thyroid carcinoma; and SSTRs, GLP1R, and GIPR in other neuroendocrine tumours. The genetic mechanisms causing the ectopic expression of GIPR in cortisol-secreting PBMAHs and unilateral adenomas have been identified, but distinct mechanisms are implicated in other endocrine tumours. Development of functional imaging targeting aberrant GPCRs should be useful for identification and for specific therapies of this wide spectrum of tumours. The aim of this review is to show that the regulation of endocrine tumours by aberrant GPCR is not restricted to cortisol-secreting adrenal lesions, but also occurs in tumours of several other organs.

Phaeochromocytoma and paraganglioma

Phaeochromocytomas and paragangliomas are rare catecholamine-producing neuroendocrine tumours which can potentially cause catastrophic crises with high morbidity and mortality. This best practice article considers the causes and presentation of such tumours, screening and diagnostic tests, management of these patients and consideration of family members at risk.

Maternal or post-weaning dietary fructo-oligosaccharide supplementation reduces stillbirth rate of sows and diarrhea of weaned piglets

Fructo-oligosaccharides (FOS) are well-known prebiotics that have the potential to improve sow reproductive performance and increase piglet growth. However, previous studies were observed in sole FOS-supplemented diets of sows or weaned piglets and did not consider the sow-to-piglet transfer effect on the performance and diarrhea rate of weaned piglets. This study explores the effects of dietary FOS supplementation on the reproductive performance of sows, and the effects of FOS supplementation at different stages on the growth performance and diarrhea rate of weaned piglets. A split-plot experimental design was used with sow diet effect in the whole plot and differing piglet diet effect in the subplot. Fifty-two multiparous sows (223.24 ± 14.77 kg) were randomly divided into 2 groups (0 or 0.2% FOS). The experiment lasted from day 85 of gestation to day 21 of lactation. Reproductive performance, glucose tolerance, placental angiogenesis, and intestinal flora of sows were assessed. At weaning, 192 weaned piglets were grouped in 2 × 2 factorial designs, with the main effects of FOS supplemental level of sow diet (0 and 0.2%), and FOS supplemental level of weaned piglet diet (0 and 0.2%), respectively. The growth performance and diarrhea rate of the weaned piglets were analyzed during a 28-d experiment. Maternal dietary supplementation of FOS was shown to reduce the stillbirth and invalid piglet rates (P < 0.05), improve the insulin sensitivity (P < 0.05) and fecal scores (P < 0.05) of sows, increase the abundance of Akkermansia muciniphila (P = 0.016), decrease the abundance of Escherichia coli (P = 0.035), and increase the isovalerate content in feces (P = 0.086). Meanwhile, the placental angiogenesis marker CD31 expression was increased in sows fed FOS diet (P < 0.05). Moreover, maternal and post-weaning dietary FOS supplementation reduced the diarrhea rate of weaned piglets (P < 0.05) and increased the content of short-chain fatty acids in feces (P < 0.05). Furthermore, only post-weaning dietary FOS supplementation could improve nutrient digestibility of weaned piglets (P < 0.05). Collectively, FOS supplementation in sows can reduce stillbirth rate, perinatal constipation, and insulin resistance, as well as improve placental vascularization barrier. Additionally, maternal and post-weaning dietary FOS supplementation reduced the diarrhea rate of weaned piglets, but only FOS supplementation in piglets alone at weaning stage could improve their nutrient digestibility.

An Unusual Case of Pheochromocytoma Associated with von Hippel-Lindau Disease and Lynch Syndrome During Pregnancy

Pheochromocytomas (PCCs) and/or paragangliomas (PGLs) are a challenge to diagnose during pregnancy because of elusive signs and testing difficulties. We report a 25-year-old woman with no pertinent medical history who presented to the hospital with hypertension, vision loss, and weakness and was initially diagnosed with preeclampsia. Imaging showed hemangioblastomas in the medulla and thoracic spine, pancreatic cysts, and a renal cyst. The endocrinology service was consulted for possible PCCs associated with von Hippel-Lindau disease (VHL). Serum and urine normetanephrine levels were elevated despite the lack of overt PCCs/PGLs seen on magnetic resonance imaging and magnetic resonance angiography. The patient was medically managed with doxazosin and then labetalol. Despite successful resection of the hemangioblastoma in the medulla, the patient suffered respiratory distress requiring tracheostomy and venous-venous extracorporeal membrane oxygenation (V-V ECMO) and fetal demise. After 3 months, the patient was discharged to rehabilitation. Follow-up genetics were heterozygous for VHL and Lynch syndrome. DOTATATE positron emission tomography/computed tomography scan showed a small hepatic focus of a maximum standard uptake value of 12.1. Altogether, this case illustrates the importance of prompt diagnosis and proper management of PCCs/PGLs during pregnancy and incorporating genetic information during surveillance to lower morbidity and mortality.

Sex-Related Differences in Self-Reported Symptoms at Diagnosis in Pheochromocytomas and Paragangliomas

Context

Biological sex can play a role in the severity of certain diseases.

Objective

Our objective was to evaluate whether sex-related differences affect the signs and symptoms of pheochromocytomas and paragangliomas (PPGLs) at presentation.

Methods

We reviewed the records of patients with PPGLs at our center from 1995 to 2022.

Results

Our study included 385 patients with PPGLs: 118 (30.6%) head and neck paragangliomas (HNPGLs), 58 (15.1%) thoracoabdominal paragangliomas (TAPGLs) and 209 (54.3%) pheochromocytomas (PHEOs). The cohort consisted of 234 (60.8%) women and 151 (39.2%) men. At diagnosis, more women than men presented with headaches (47.5% vs 32.4%; P = .007); however, more men presented with diabetes (21.1% vs 12.5%; P = .039). When subdivided by tumor location, headaches occurred more often in women with HNPGLs and TAPGLs (31.0% vs 11.4%; P = .0499 and 60.0% vs 21.7%; P = .0167). More men presented with diabetes among patients with PHEOs (28.2% vs 11.2%; P = .0038). In regard to nonsecretory PPGLs, women presented with a higher prevalence of headaches (46.9% vs 3.6%; P = .0002), diaphoresis (16.3% vs 0.0%; P = .0454), and palpitations (22.4% vs 0.0%; P = .0057). In patients with secretory tumors, women presented with more headaches (58.9% vs 42.7%; P = .0282) and men with more diabetes (29.3% vs 12.5%; P = .0035).

Conclusion

In our cohort, more women presented with headaches across all tumor types and secretory statuses. More men presented with diabetes among patients with PHEOs and secretory tumors. In nonsecretory PPGLs, women had more adrenergic symptoms. These findings can be explained by differences in adrenergic receptor sensitivity, self-reported symptoms, and possibly other vasoactive peptides and sex-hormone status.

The diagnosis and management of pheochromocytoma and paraganglioma during pregnancy

Diagnosis of pheochromocytoma or paraganglioma (PPGL) in pregnancy has been associated historically with high rates of materno-fetal morbidity and mortality. Recent evidence suggests outcomes are improved by recognition of PPGL before or during pregnancy and appropriate medical management with alpha-blockade. Whether antepartum surgery (before the third trimester) is required remains controversial and open to case-based merits. Women with PPGL in pregnancy are more commonly delivered by Caesarean section, although vaginal delivery appears to be safe in selected cases. At least some PPGLs express the luteinizing hormone/chorionic gonadotropin receptor (LHCGR) which may explain their dramatic manifestation in pregnancy. PPGLs in pregnancy are often associated with heritable syndromes, and genetic counselling and testing should be offered routinely in this setting. Since optimal outcomes are only achieved by early recognition of PPGL in (or ideally before) pregnancy, it is incumbent for clinicians to be aware of this diagnosis in a pregnant woman with hypertension occurring before 20 weeks' gestation, and acute and/or refractory hypertension particularly if paroxysmal and accompanied by sweating, palpitations and/or headaches. All women with a past history of PPGL and/or heritable PPGL syndrome should be carefully assessed for the presence of residual or recurrent disease before considering pregnancy.

HCG-responsive aldosteronoma with transient secretion during pregnancy confirmed through HCG-stimulated adrenal venous sampling

Primary aldosteronism can be regulated by the ectopic expression of G-protein coupled receptors in aldosteronomas or bilateral hyperplasias. We report a rare case of a young woman in whom 2 pregnancies were complicated by pre-eclampsia and 1 miscarriage. The transient primary aldosteronism during pregnancies suggested the possibility of HCG stimulated aberrant adrenal expression of LHCG receptor in her adrenal tissues. This was supported by increased aldosterone and renin suppression during 5-day HCG stimulation test outside of pregnancy. Following a second 5-day HCG stimulation test, bilateral simultaneous adrenal vein sampling identified a lateralized source of aldosterone from an 8 mm right adrenal nodule. A right laparoscopic adrenalectomy resulted in clinical and biochemical cure and allowed a further uneventful pregnancy a few years later. This case illustrates the indication to investigate for potential primary aldosteronism in woman with transient hypertension during pregnancy.

Primary Functioning Hepatic Paraganglioma Treated by Laparoscopy: A Case Report

Paragangliomas are highly vascularised and often heritable tumors derived from the paraganglia. They are typically discovered in the retroperitoneal space as well as the head and neck region but are rarely encountered in the liver parenchyma. We report a case of a primary functioning hepatic paraganglioma and provide an up-to-date literature review of patients with such tumors. We present a case of functioning paraganglioma in a 34-year-old female patient who suffered a solitary lesion in her left lateral lobe with symptoms of hypertension since pregnancy. She did not have any family history and her pre-pregnancy examination was negative. An abdominal CT imaging revealed a 6.5 × 5.7 cm liver lesion in segments II and III. Laboratory investigations identified elevation in plasma-free catecholamines. With sufficient preoperative preparation, the patient underwent laparoscopic left hemihepatectomy. Immunohistochemical staining revealed Syn (+) tumor cell nests surrounded by S-100 sustentacular cells (+), providing a definitive diagnosis of paraganglioma. The patient recovered uneventfully without signs of recurrence during a 1-year follow-up period. Our case demonstrates that primary refractory hypertension in pregnancy should be screened for paraganglioma through abdominal ultrasound and plasma free catecholamines. On the other hand, laparoscopic surgery is technically safe and feasible for the treatment of patients with hepatic paragangliomas in favorable locations.