Properties of Incidentaloma in Adrenal and Renal Tumors

Kim, Jae Hyoun; Kwon, Tae Gyun; Chang, Sae Kook

Abstract

PURPOSE: Recent advances and wider application of imaging diagnostic techniques, especially ultrasonography(USG) and computed tomography(CT), account for the increasing incidentaloma in adrenal and renal tumors. We have studied these incidentalomas to investigate the incidences, occasions of detection, pathological findings, prognosis and other clinical properties.
MATERIALS AND METHODS
The 186 cases of adrenal and renal tumors, treated surgically in Kyoungpook National University Hospital between 1987 and 1997 were reviewed and compared incidentally detected group(59cases) to symptomatically suspected group(127cases).
RESULTS
The analysis of 186 cases demonstrated a marked increase in the frequency of incidentaloma from 15.6%(1987?1992) to 43.1%(1993?1997). The proportions of incidentaloma in adrenal and renal tumors were 20.4% in adrenal tumor, 36.4% in renal tumor and 31.7% in total. The chief method of detection was USG(57.6%), followed by CT(33.9%) and IVP(6.8%). The main reasons for examination leading to the diagnosis in incidentaloma were evaluation of unrelated symptoms(44.1%), follow up of other diseases(35.6%), general health check(18.6%) and during other operation(1.7%). In case of adrenal incidentaloma, the mean tumor diameter was larger than in suspected group(4.8+/-3.4cm vs 3.1+/-2.3cm). The main histologic diagnosis of adrenal incidentaloma was adrenal adenoma and hormonally functional tumors were less than suspected group (63.6% vs 88.4%). In case of renal incidentaloma, the mean tumor diameter was smaller than in suspected group(5.3+/-2.1cm vs 8.7+/-2.2cm) and paraneoplastic syndromes were less than in suspected group(20.8% vs 57.1%). The grade and stage of renal incidentaloma were lower and survival rate was higher than suspected group(5 year survival rate, 83.3% vs 64.3%).
CONCLUSIONS
These results indicated that abdominal USG or CT should be performed with special attention to adrenal and renal lesions, where at a health examination or evaluation to unrelated disease.