OBJECTIVE: Phaeochromocytomas (PCCs) are widely known for their clinical
unpredictability. This study intends to define predictive plasma markers
for their variable postoperative behaviour. Furthermore, the diagnostic
accuracy of these plasma tests was determined. DESIGN AND METHODS: A
retrospective correlative study was performed in a series of 83 operated
and four autopsied patients in order to correlate preoperative
catecholamine (CAT) levels of 103 PCCs with their clinical behaviour. In a
subset of cases, chromogranin-A (Chr-A) and enzymes/precursors of the CAT
biosynthesis were studied for their predictive value. RESULTS: Basal CAT
levels were elevated in 81/87 instances (sensitivity: 93%). Four of six
cases with normal measurements showed only medullary hyperplasia. Larger
PCCs, particularly those showing necrosis, capsular and vascular invasion,
secreted higher CAT levels. Bilateral, hereditary tumours were less
productive than their unilateral counterparts. Extra-adrenal PCCs secreted
significantly lower levels of epinephrine (EPI) than intra-adrenal
tumours. Fourteen patients developed metastases. According to Kaplan-Meier
estimations, patients with higher levels of dopamine, norepinephrine (NE)
and aromatic l-amino acid decarboxylase as well as lower ratios of
EPI/EPI+NE, had significantly shorter metastases-free intervals. Existence
of preoperative hypertension, left ventricular hypertrophy and measured
blood pressures showed significant positive relationships with CAT levels,
but not with Chr-A. CONCLUSIONS: These data showed that plasma CAT
measurement is a sensitive method in the diagnostic work-up of PCCs. Those
tumours producing normal levels are commonly small and asymptomatic.
Furthermore, certain secretion patterns are indicative of the presence of
metastases as well as the size and site of spor
