The natural history of incidentally discovered adrenocortical adenomas: A retrospective evaluation

Abstract

Adrenal adenoma is the most frequent lesion among adrenal incidentalomas. The present retrospective study was undertaken to investigate medium-term evolution of supposed or ascertained adrenocortical adenomas in a group of 53 subjects (16 males and 37 females, aged 31-83 yr), with bilateral (no.=8) or monolateral (no.=45) incidentally discovered adrenal masses (size 10-50 mm, median 25 mm), who were followed-up for 6-78 months (median 24 months). Diagnosis of adenoma was based on size and morphovolumetric aspect of the lesion at computed tomography (CT), scintigraphic pattern using NP59 as a tracer, and it was histologically confirmed in 7 patients. After an extensive hormonal investigation including morning (no.=53) and midnight (no.=28) serum cortisol, plasma ACTH (no.=50), serum DHEAS (no.=51), daily urinary free cortisol excretion (no.=52), post-dexamethasone (1 mg) cortisol (no.=42) and ACTH stimulation test for 17-hydroxyprogesterone (17-OHP) response (no.=48) at the time of diagnosis, patients were periodically re-evaluated for hormonal function and radiological aspect of the lesion(s) by CT. Seven patients underwent surgery 6-42 months after incidentaloma demonstration, with histological diagnosis of adrenal adenoma. During follow-up an increase in the size of the lesion was demonstrated in 22 patients (41.5%); the increase was greater than 10 mm in 8 cases. In 3 patients with unilateral mass, a contralateral lesion appeared 10-52 months after first demonstration. Six patients (11.3%) showed reduction or disappearance of the lesions. On the basis of the hormonal evaluation 3 patients were considered to have subclinical Cushing's syndrome and 10 patients exhibited 17-OHP hyperresponse to ACTH test consistent with partial 21 -hydroxylase deficiency. A significant difference in the size of the lesions was observed between patients with or without 17-OHP hyperresponse to ACTH test (31.1 1.9 vs 24.1 +/- 1.2 mm; p<0.01). No significant changes in the hormonal parameters were observed in the patients, when retested. In conclusion, although none of the patients of the present series exhibited evolution to hypersecretion or to aberrant growth, in more than 40% of patients an increase in the size of the mass was observed, even after a long period of "quiescence". This suggests that a radiological re-evaluation of lesions should be periodically undertaken.

Long-term follow-up study of patients with adrenal incidentalomas

“…Newly diagnosed subtle endocrine alterations appeared in 28% of the patients, most of them featuring a decrease in DHEA-S and ACTH levels, as previously reported (14,15). Similar small changes in hormonal function have been reported by Barzon et al (14) and Grossrubatscher et al (15).…”

Prevalence and natural history of adrenal incidentalomas

“…Terzolo et al (87) reported a spontaneous endocrine normalization in 50% of patients with subclinical hypercortisolism, whereas no patient developed clinical Cushing's syndrome. At variance, in other reports subclinical hypercortisolism persisted throughout follow-up or became clinically evident in some patients (62,67,83,90,104,116). In our experience, one out of eight patients with subclinical Cushing's syndrome at diagnosis developed overt Cushing's syndrome during follow-up (53).…”

“…Whether these features, which are typical of the metabolic syndrome, will have an impact on the long-term morbidity of patients with subclinical Cushing's syndrome remains to be determined. Long-term perspective studies are lacking; however, an amelioration of clinical or biochemical abnormalities in patients with subclinical hypercortisolism after surgery has been reported (42,51,53,66,67,(88)(89)(90). Improvement of blood pressure, obesity, metabolic abnomalities, collagen and bone turnover markers was observed after adrenalectomy in patients with subclinical Cushing's syndrome (51,66,67).…”

Long-term morphological and hormonal follow-up in a single unit on 115 patients with adrenal incidentalomas

“…Barzon et al (1999) reported that incidentalomas tend to undergo a period of increase in mass size but thereafter remain unchanged, suggesting the possible existence of a programmed end point of growth of adrenal masses. In contrast, Grossrubatscher et al (2001) found that adrenal mass enlargement may occur unpredictably at any time, sometimes after a long period of 'quiescence'. In the present study we noted frequent increments but also reductions in mass size, although such variations consistently proved to be small.…”

“…Other authors have similarly reported the development of overt hypersecretion of the mass over time and even occasional malignant transformation of adrenal incidentalomas (Hensen et al, 1990;Jockenhovel et al, 1992). In contrast, no shift toward malignancy or functional hyperactivity was observed in several other studies (Osella et al, 1994;Barry et al, 1998;Terzolo et al, 1998;Rossi et al, 2000;Siren et al, 2000;Grossrubatscher et al, 2001). Thus, the natural course of adrenal incidentalomas still requires further clarification.…”