Massas adrenais clinicamente silenciosas, diagnosticadas ao acaso ("incidentalomas"), são frequentemente encontradas em avaliações radiológicas devido ao constante progresso dos métodos de imagem. Na revisão das principais fontes científicas até 2004, analisado o grau de evidência concluiu-se: a maioria dos "incidentalomas" são não hipersecretores, mas a avaliação endócrina demonstrou que é comum o achado de hiperfunção hormonal discreto; "incidentaloma" acima de 6cm sugerem malignidade e entre 4-6cm devem ser analisadas por suas características de imagem; adrenalectomia deve ser indicada em massas adrenais funcionantes; massas adrenais não operadas devem ser acompanhadas pelo prazo de 2 anos

Introduction: Clinically silent adrenal masses, incidentally diagnosed during imaging methods performed for other clinical conditions (“incidentalomas") have been more frequently detected due to the constant improvement in imaging methods. There are several causes, diagnoses and treatments for these masses. Thus, whenever a physician comes across such lesion, it is necessary to define whether this mass is hormonally active and whether there is a risk of being malignant. Nevertheless, the methods for clarifying these issues have yet to be defined. Objective: To evaluate the best diagnosis, treatment and follow up of the incidental adrenal lesion. Methods: The main scientific literature available until October 2004 was reviewed, taking evidence into account. Results: Two studies which selected and reviewed articles until September 2003 were found. Fourty-three other studies included in a systematic review until October 2004 were added to this study. Conclusions: In general, “incidentalomas" are non-functioning, but endocrinological evaluation has shown that subclinical hormonal hyperfunction is not unusual, thus stressing the need for measuring substances such as with metanephrine assay, dexamethasone suppression test in low dosage and establishing the upright plasma aldosterone/plasma renin activity ratio. Non-functioning “incidentalomas" smaller than 4 cm should be followed carefully; those between 4 and 6 cm should be analyzed for its imaging characteristics; for those greater than 6 cm adrenalectomy is indicated. Functioning “incidentalomas" must undergo adrenalectomy. Nonoperated adrenal masses must be followed for two years through imaging and function testing.