Department of Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Compr Physiol. 2014 Apr;4(2):691-713. doi: 10.1002/cphy.c130034.
The principal function of the adrenal medulla is the production and secretion of catecholamines. During stressful challenging conditions, catecholamines exert a pivotal homeostatic role. Although the main adrenomedullary catecholamine, epinephrine, has a wide array of adrenoreceptor-mediated effects, its absence does not cause life-threatening problems. In contrast, excess production of catecholamines due to an adrenomedullary tumor, specifically pheochromocytoma, results in significant morbidity and mortality. Despite being rare, pheochromocytoma has a notoriously bad reputation because of its potential devastating effects if undetected and untreated. The paroxysmal signs and symptoms and the risks of missing or delaying the diagnosis are well known for most physicians. Nevertheless, even today the diagnosis is still overlooked in a considerable number of patients. Prevention and complete cure are however possible by early diagnosis and appropriate treatment but these patients remain a challenge for physicians. Yet, biochemical proof of presence or absence of catecholamine excess has become more easy and straightforward due to developments in assay methodology. This also applies to radiological and functional imaging techniques for locating the tumor. The importance of genetic testing for underlying germline mutations in susceptibility genes for patients and relatives is increasingly recognized. Yet, the effectiveness of genetic testing, in terms of costs and benefits to health, has not been definitively established. Further improvement in knowledge of genotype-phenotype relationships in pheochromocytoma will open new avenues to a more rationalized and personalized diagnostic approach of affected patients.
肾上腺髓质的主要功能是产生和分泌儿茶酚胺。在应激挑战性条件下，儿茶酚胺发挥着关键的体内平衡作用。尽管主要的肾上腺髓质儿茶酚胺肾上腺素具有广泛的肾上腺素能受体介导的作用，但它的缺失不会导致危及生命的问题。相比之下，由于肾上腺髓质肿瘤（特别是嗜铬细胞瘤）产生的儿茶酚胺过量会导致严重的发病率和死亡率。尽管嗜铬细胞瘤很少见，但由于其潜在的破坏性影响，如果未被发现和未得到治疗，它的声誉却很差。大多数医生都知道阵发性症状和错过或延迟诊断的风险。然而，即使在今天，由于诊断方法的发展，仍有相当数量的患者被忽视。通过早期诊断和适当的治疗，可以预防和完全治愈，但这些患者仍然是医生的挑战。然而，由于检测方法的发展，儿茶酚胺过多的生化证据已经变得更加容易和直接。这也适用于定位肿瘤的放射性和功能成像技术。对患者和亲属易感性基因种系突变的基因检测的重要性日益得到认识。然而，基因检测在成本和健康效益方面的有效性尚未得到明确确立。进一步提高对嗜铬细胞瘤基因型-表型关系的认识，将为受影响患者的更合理和个性化的诊断方法开辟新途径。
