[Pheochromocytoma: pediatric features]

[High pressure trap]

Pheochromocytoma is a rare tumor potentially life-threatening and associated with non specific and diverse symptomatology. Cardiac symptoms may mislead diagnosis; they could manifest as myocardial sideration concomitant to a hypertensive peak or supraventricular arythmia. We report a case of pheochromocytoma associated with hypokaliemia revealed by a myocardial ischemia with acute cardiac failure and severe left ventricular depression and complete reversal after surgery.

[Management of bilateral pheochromocytoma - case report]

Le phéochromocytome est une pathologie rare et sévère; sa survenue à un âge précoce, sa bilatéralité et son association à des signes de gravité en font la sévérité. Notre observation en fait l'exemple; le phéochromocytome bilatéral est révélé par un accident vasculaire ischémique qui a dominé le tableau initial chez une fille de 10 ans. L'imagerie a orienté vers le diagnostic (échographie et TDM abdominales), confirmé par le dosage des catécholamines urinaires. Après une préparation soigneuse, l'exérèse chirurgicale (surrénalectomie totale droite et partielle gauche), avec bonne surveillance péri opératoire, ont permis d'avoir de bons résultats. L’étude histologique a étayé la nature anatomo pathologique de la pièce opératoire.

Hypertension in childhood cancer: a frequent complication of certain tumor sites

The clinical features and management of severe hypertension (HT) (blood pressure > 99th percentile + 5 mm Hg) have been rarely described in pediatric oncology.

OBJECTIVES

Retrospective descriptive study of the case files of 31 patients followed in the Institut Curie Department of Pediatric Oncology between 1999 and 2004 and presenting severe HT at the time of diagnosis of their tumor.

RESULTS

The median age was 2 years 1 month (range: 3 mo to 6 y 8 mo). Median blood pressure was 99th percentile + 30 mm Hg (range: 99th percentile + 7 mm Hg to 99th percentile + 62 mm Hg). The tumors presented by these children were: Wilms tumor (n=17, ie, 20% of all Wilms tumors treated during this period), neuroblastoma (n=12, ie, 10% of all neuroblastomas treated during this period) or other tumors (n=2). HT was asymptomatic in all children. Initial management consisted of etiologic treatment by primary chemotherapy and/or surgical resection of the tumor, associated with antihypertensive therapy, initially administered by intravenous injection for 12 children (nicardipine, labetalol) and then orally in all children (calcium channel blockers, n=23; angiotensin-converting enzyme inhibitor, n=16; beta-blockers, n=4; alpha/beta-blockers, n=2; diuretics, n=1). Dual therapy was necessary in 7 cases and triple therapy was necessary in 1 case. The median duration of antihypertensive therapy was 40 days (range: 9 to 195). No child developed a serious complication of HT.

CONCLUSIONS

Initial HT is a frequent complication of Wilms tumor and neuroblastoma and affects young children (< 2.5 y). It is often severe, asymptomatic, but needs specific treatment and resolves after treatment of the tumor.

[Anaesthetic particularities for children with tumours]

OBJECTIVES

To present the more frequent solid tumors, that require a general anaesthesia and to describe the particularities of the anaesthetic management.

DATA SOURCES AND EXTRACTION

The PUBMED database was searched for articles (1990 - 2005) combined with references analysis of major articles on the topics.

DATA SYNTHESIS

Neoplasma is the first cause of paediatric death. In children less than 5 years of age, neuroblastoma and nephroblastoma are the more frequent of the tumour. The incidence of each pathology is low. However a general anaesthesia is required in numerous situations: bone marrow aspiration and biopsy, central venous catheter insertion, various biopsies under computed tomography, ultrasound, thoracoscopy or laparoscopy, MRI scan, surgery and body radiation. The key points of successful anaesthetic management include complete preoperative evaluation together with the oncology paediatric team. Particularly, cardiotoxicity may result from chemotherapy and hypertension is frequently associated with neuroblastoma and nephroblastoma. Mediastinal location of lymphomas induced a significant risk of cardiopulmonary complications during induction of general anaesthesia. A peak expiratory flow rate or a tracheal cross-section area less than 50% of predicted values are contraindication to general anaesthesia. Cephalic rhabdomyosarcoma may be responsible of difficult airway management. Specific guidelines are available for platelet and red cell transfusion in paediatric oncology patients. Surgical antibioprophylaxis are adapted in immunodepressed children to a potential increased risk of postoperative infectious complications, according personal previous history, microbiological ecology and body bacterial flora. Dosage of anaesthetic agents takes into account denutrition, hydroelectrolytic disturbances and hypovolemia.

Hypertension and adrenal disorders

Adrenal disorders causing hypertension can be related to the dysfunction of either the adrenal cortex or the adrenal medulla. These disorders, including congenital adrenal hyperplasia (CAH), owing to 11B-hydroxylase deficiency and to 17alpha-hydroxylase deficiency; apparent mineralocorticoid excess; familial hyperaldosteronism type I; primary aldosteronism; Cushing's syndrome; and familial glucocorticoid resistance, primarily affect the adrenal cortex and cause low-renin hypertension. The classic disorder of the adrenal medulla resulting in hypertension is pheochromocytoma, although hypertension in obesity might also be associated with catecholamine secretion. In this review, we discuss these etiologies and the most recent advances in our knowledge of their pathophysiology, diagnosis, and treatment.

[Pheochromocytoma in children. Two case reports]

Severe sustained hypertension occurs in only 0.1% of the pediatric population and only about 2% of these patients will have an underlying endocrine cause. Pheochromocytoma as a catecholamine secreting tumour causing severe hypertension is exceedingly rare in children. A high index of suspicion and an awareness of the clinical spectrum are therefore necessary to make the diagnosis. We report two cases of pheochromocytoma occurring in two a 12 year-old boys who's presented with sustained hypertension, headache, sweating, and visual blurring. Measurement of 24 hour urinary catecholamines showed a marked increase and localization of adrenal unilateral pheochromocytoma was determined by ultrasonography and computed tomography. The approaches to the adrenal gland were transverse transperitoneal and the excision of the tumors was followed of return to the normal of tensional numbers.

Molecular characterization of a pediatric pheochromocytoma with suspected bilateral disease

An 11-year-old boy with hypertension was suspected of having bilateral adrenal pheochromocytomas and hyperplasia. Molecular analysis of specific tumor suppressor genes and oncogenes excluded the familial syndromes, von Hippel-Lindau (VHL) disease and multiple endocrine neoplasia (MEN) type 2A. Further evaluation identified a unilateral adrenal pheochromocytoma with a VHL heterozygous somatic mutation (G695A) and loss of the maternal allele at 11p15.5-11p14 exclusively in the tumor tissue. Both reverse-transcriptase polymerase chain reaction and immunohistochemistry confirmed increased expression of IGF2 within the tumoral tissue, relative to a normal control adrenal gland. These results ruled out familial syndromes and suggested that the VHL mutation and the loss of maternal allele on chromosome 11 could have contributed to tumor development.