Background: Adrenal incidentalomas are becoming increasingly common due to the improvements in imaging techniques, increasing numbers of radiological investigations and an aging population. The current follow-up protocols are designed to avoid missing clinically relevant lesions (e.g. malignancy or hormone hypersecretion) by recommending repeated radiological and biochemical investigations. Large amounts of money are spent on patients who as it seems mostly have benign and non-functioning lesions that warrant no further treatment.
Objectives: The aim of this study is to assess how frequently these tumours cause problems in terms of tumour growth, malignancy and/or hypersecretion of hormones.
Methods: The design of the study is a retrospective study based on patient records. Eighty-one patients (42 females and 39 males) were investigated. General data (age, sex, etc), imaging characteristics, hormone work-up and diagnoses were collected and analysed. The number of operations has also been included.
Results: The median age at discovery of the adrenal incidentalomas was 63 years old (range 2084). The prevalence of NFAs was highest in the age group from 60 to 70 years old. The median size of the adrenal incidentalomas when discovered was 2.3 cm (range 0.722 cm). During the follow-up only one mass (1%) showed a significant increase in size, all the other masses remained stable. None of the incidentalomas became functional (excessive hormone production) during the follow-up period. Four (5%) patients were diagnosed with adrenal cortical carcinoma, 56 (69%) with NFA, two (3%) with Cushings, 5 (6%) with Subclinical Cushings, 5 (6%) with pheochromocytoma, 1 (1%) with Conns and 8 (10%) were diagnosed otherwise. There were no metastases. Seventeen patients underwent adrenalectomy. The difference in prevalence between males and females was statistically not significant (P value: 0.345). The CT scan was the most used diagnostic technique.
Discussion: The majority of the incidentalomas were benign and non-functioning. However, a considerate number of functional and malignant tumours was found. Only one mass progressed during the follow-up period. A cost-effectiveness evaluation is necessary to assess how the expenses that are currently spent on the follow-up of benign tumours can be minimised.