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Early detection of a pheochromocytoma is necessary to avoid the cardiovascular complications of hypertension and to recognize the 10% of malignant neoplasms. Hypertensive changes, particularly hypertensive spikes and stable hypertension are the most common clinical features. A pheochromocytoma must be suspected in presence of various symptoms of which cephalea, tachycardia, diaphoresis are the most frequently encountered. Plasma catecholamines and 24-hours urine metabolites measurements have 60-100% and 72-99% sensitivity respectively. Radiologic procedures commonly used to locate a pheochromocytoma include CT and RM: they achieve 100% sensitivity for unilateral adrenal lesions and respectively 64% and 88% sensitivity for extra-adrenal lesions. Scintigraphic localization with MIBG provides functional informations and is recommended for follow-up of the recurrent or metastatic pheochromocytoma. Preoperative medical treatment using alpha and beta blocking agents or calcium channel blockers has contributed to reduce perioperative morbidity and mortality. Anterior transabdominal approach is advocated as the standard operative procedure; this approach allows ready access to any site where tumors are obviously present and permits thorough exploration of the abdominal cavity for additional contralateral adrenal or extra-adrenal lesions. An accurate preoperative localization of a sporadic, unilateral, of less than 7-10 cm, benign neoplasm constitutes the indication for the laparoscopic adrenalectomy. Pheochromocytoma-free survival were 92% and 80% at 5 and 10 years respectively; in living patients without recurrence, hypertension-free survival was 74% and 45% at 5 and 10 years respectively. Extra-adrenal pheochromocytomas are frequently malignant (36%) and are associated with a high incidence of persistent or recurrent disease (32%).

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PURPOSE: Although it has been widely accepted as the evidence supporting prophylactic carotid endarterectomy, aspects of the Asymptomatic Carotid Atherosclerosis Study have left unease among clinicians who must decide which individuals without symptoms should undergo surgery. Additional confusion has been created by the fact that the several large randomized trials investigating the efficacy of carotid endarterectomy have classified and analyzed different categories of carotid stenosis. In an effort to provide more information on the natural history of asymptomatic, moderate carotid artery stenosis (50% to 79%), we have reviewed data on approximately 500 arteries. METHODS: Records of our vascular laboratory from 1990 to 1992 were reviewed. We identified 425 patients with asymptomatic, moderate carotid artery stenosis; 71 patients had bilateral stenoses in this category, resulting in 496 arteries for study. RESULTS: The mean length of follow-up was 38 +/- 18 months. New ipsilateral strokes occurred in 16 (3.8%) patients. New ipsilateral transient ischemic attacks occurred in 25 (5.9%) patients. Documented progression of stenosis occurred in 48 (17%) of the 282 arteries for which a repeat duplex examination was available. Arteries that progressed to > 80% stenosis were significantly more likely to have caused strokes than those that remained in the 50% to 79% range (10.4% vs 2.1%, p < 0.02). Conversely, arteries that remained stable in the degree of stenosis were significantly more likely to have remained asymptomatic than those that progressed (92.7% vs 62.5%, p < 0.001). With life-table analysis the estimated cumulative ipsilateral stroke rate was 0.85% at 1 year, 3.6% at 3 years, and 5.4% at 5 years. The respective estimated cumulative transient ischemic attack rates were 1.9%, 5.5%, and 6.3%. The respective estimated cumulative rates for progression of stenosis were 4.9%, 16.7%, and 26.5%. Life-table comparison of ipsilateral stroke revealed a significantly higher cumulative rate among arteries that progressed in the degree of stenosis than among those that remained stable (p < 0.001). CONCLUSIONS: Based on the low rate of permanent neurologic events in these cases, prophylactic carotid endarterectomy for the asymptomatic, moderately stenotic internal carotid artery cannot currently be recommended. The only factor that appears to predict increased risk for future stroke is progression of stenosis. Careful follow-up with serial repeat duplex examinations must be performed in these patients. Until there are widely accepted duplex parameters that can provide all clinicians with accurate identification of arteries with narrowing corresponding to 60% stenosis as defined by the Asymptomatic Carotid Atherosclerosis Study, all surgeons will need to be aware of specifically how their noninvasive laboratories are deriving their results. For the many laboratories that continue to use the University of Washington criteria, 80% should remain the level above which prophylactic carotid endarterectomy is warranted.

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