RESUMEN
Phaeochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors with clinical heterogeneity and a high association with hereditary disease, affecting approximately 30 % of the cases. Differences in the presentation and genetic etiologies of PPGLs have been demonstrated between Chinese and European patients. The frequency of germline genetic diagnosis was remarkably higher in Brazilian patients (â¼50 %) compared with other cohorts (Chinese 21 %, European 31 %, and The Cancer Genome Atlas Program cohort 27 %). Interestingly, germline SDHB genetic defects were also more prevalent in Brazilian patients (17 %) with PPGLs when compared with other cohorts (3-9 %). The SDHB exon 1 deletion was responsible for approximately 50 % of the SDHB pathogenic/likely pathogenic variants in Brazilian patients with PPGLs due to a founder effect. The germline SDHB exon 1 deletion represents â¼10 % of the germline drivers in Brazilian patients (and possibly in Latin America). Therefore, a single diagnostic PCR for the SDHB exon 1 deletion might be very useful in clinical practice for genetic testing and counseling of patients with PPGLs in Latin America.
RESUMEN
ABSTRACT Phaeochromocytoma and paraganglioma are rare catecholamine-producing tumours, recognised to have one of the richest hereditary backgrounds of all neoplasms, with germline mutations seen in approximately 30% of patients. They can be a part of genetic syndromes such as MEN 2 or Neurofibromatosis type 1, or can be found as apparently sporadic tumours. Germline mutations are almost always found in syndromic patients. Nonetheless, apparently sporadic phaeochromocytoma too show high germline mutation rates. Early detection of a genetic mutation can lead to early diagnosis of further tumours via surveillance, early treatment and better prognosis. Apart from this, the genetic profile has important relevance for tumour location and biochemical profile, and can be a useful predictor of future tumour behaviour. It also enables family screening and surveillance. Moreover, recent studies have demonstrated significant driver somatic mutations in up to 75% of all tumours. Arch Endocrinol Metab. 2017;61(5):490-500
Asunto(s)
Humanos , Paraganglioma/genética , Feocromocitoma/genética , Neoplasias de las Glándulas Suprarrenales/genética , Mutación de Línea Germinal/genéticaRESUMEN
El feocromocitoma es un tumor de baja prevalencia que se origina en las células cromafines de la médula de las glándulas suprarrenales. Estos tumores como el tejido simpático normal se originan del neuroectodermo. La tríada clásica de presentación clínica es: hipertensión que puede ser persistente, paroxística o fluctuante, cefalea grave pulsátil acompañada de náuseas y/o vómito y palpitaciones con taquicardia o bradicardia refleja; pero también se pueden presentar un gran número de síntomas debido al exceso de catecolaminas plasmáticas, llegando incluso a producir un síndrome coronario agudo. Su diagnóstico se realiza por medio de la clínica (para la cual se requiere un alto grado de sospecha), el laboratorio y la imagenología. El tratamiento de elección es la resección quirúrgica del tumor por laparoscopia o cirugía abierta.
A phaeochromocytoma is a tumour of low prevalence that originates in the chromaffin cells of the medulla of the adrenal glands. These tumours, like normal sympathetic tissue, originate from neuroectoderm. The classic triad of clinical findings are: hypertension that can be persistent, paroxysmal or fluctuating, severe throbbing headache accompanied by nausea and/or vomiting, and palpitations with tachycardia or reflex bradycardia. It can also present with a myriad of symptoms due to the excess of plasma catecholamines, even producing an acute coronary syndrome. Diagnosis is made through the clinical (for which requires a high degree of suspicion), laboratory, and imaging findings. The treatment is surgical resection of the tumour by laparoscopy or open surgery.
Asunto(s)
Humanos , Feocromocitoma , Síndrome Coronario Agudo , CatecolaminasRESUMEN
OBJECTIVE: To investigate the positive predictive value (PPV) of urinary vanillylmandelic acid (VMA) testing in the diagnosis of phaeochromocytoma and to describe the features associated with phaeo chromocytoma at the University Hospital of the West Indies (UHWI). SUBJECTS AND METHODS: There were 551 VMA tests performed from January 2003 to June 2009 and 122 tests in 85 patients were elevated (ie > 35 µmol/24 hr). The study patients were categorized as: (i) 'surgical' (5 patients who underwent surgery) or (ii) 'non-surgical' (remaining 80 patients). Forty medical charts (out of 85) were reviewed using a standardized data extraction form. RESULTS: The median age for patients in the non-surgical group (with charts reviewed, n = 35) was 36 years (range 9-70) and the median VMA was 43 µmol/24 hr (IQR 38-51). Of these patients, 83% had one or no symptom typical of phaeochromocytoma. In the surgical group the median VMA was 58 µmol/24 hr (IQR 44-101); phaeochromocytoma was confirmed histologically in 3 patients, all of whom had several symptoms typical of catecholamine excess. VMA testing had a PPV of 8%, specificity of 79% and sensitivity of 100%. CONCLUSIONS: VMA testing at UHWI has poor specificity and high sensitivity. These results contrast with international data showing that VMA testing is poorly sensitive but highly specific. The use of assays with higher specificity (egplasma or urinary metanephrines) may represent a more cost-effective approach to biochemical screening at UHWI.
OBJETIVO: Investigar el valor predictivo positivo (VPP) de las pruebas del ácido vanilmandélico urinario (VMA) en el diagnóstico de la feocromositoma y describir las características asociadas con la feocromositoma en el Hospital de la Universidad de West Indies (HUWI). SUJETOS Y MÉTODOS: Se realizaron unas 551 pruebas de VMA de enero de 2003 a junio de 2009, y 122 de las pruebas en 85 pacientes tuvieron resultados elevados (ie > 35 µmol/24 hr). Los pacientes del estudio fueron clasificados como: (i) "quirúrgicos" (5 pacientes que se sometieron a cirugía) ó (ii) "no quirúrgicos" (los 80 pacientes restantes). Se revisaron cuarenta historias clínicas (de 85) mediante un formulario estandarizado de extracción de datos. RESULTADOS: El promedio de edad de los pacientes en el grupo no quirúrgico (con historias clínicas, n = 35) fue de 36 años (rango 9-70) y la mediana VMA fue 43 µmol/24 h (IQR 38-51). De estos pacientes, 83% tenían uno o ningún síntoma típico de la feocromositoma. En el grupo quirúrgico la mediana VMA fue 58 µmol/24 h (IQR 44-101). La feocromositoma fue confirmada histológicamente en 3 pacientes, cada uno de los cuales presentó síntomas típicos de exceso de catecolaminas. Las pruebas de VMA tuvieron un VPP de 8%, una especificidad de 79%, y una sensibilidad de 100%. CONCLUSIONES: Las pruebas de VMA en HUWI poseen pobre especificidad y alta sensibilidad. Estos resultados contrastan con los datos internacionales que muestran que la prueba de VMA es pobremente sensible pero altamente específica. El uso de ensayos con mayor especificidad (por ejemplo, metanefrinas plasmáticas o urinarias) puede representar un método costo-efectivo a la hora de realizar el pesquisaje bioquímico en HUWI.