Endocrine Abstracts

Background: Current guidelines suggest against further imaging follow-up (FU) of patients with non-functioning adrenal masses with clear benign features on imaging studies.

Aim: To analyse the data of patients with non-functioning adrenal masses who had FU at Vilnius University Hospital Santariskiu Klinikos (VUHSK) from 2010 to 2016.

Methods: Cases coded as D35.0; D44.1; C74.1; C74.9; E26.0; E27,8; E24,8 according to ICD-10 classification were retrieved from database. Electronic data capture system was used to extract CT scans and biochemical testing data retrospectively.

Results: There were 714 subjects assessed for adrenal masses from 2010 to 2016 at VUHSK. At least one FU and non-functioning adrenal masses with obvious benign features on CT scan had 216 subjects and thus were included into further analysis. They were 61.6±11.2 years of age (184 female) with tumour size at baseline of 22.8±12.8 mm. Average FU time was 4.1±1.4 years (from 2 to 7), during which tumour size increased in 84 (39%), decreased in 48 (22%), did not change in 84 (39%) cases. Significant increase (by > 20% in addition to at least 5 mm increase in maximum diameter) was observed in 19 (8.8%) cases. Average size of 19 significantly enlarged tumours changed from 19.37±7.60 mm to 30.58±13.68 mm in 2.7±1.4 years. All these tumours were associated with female gender. Despite tumour size enlargement, none of them became functioning during observation time.

Conclusions: Our study showed, that the significant enlargement of non-secreting initially benign adrenal masses during follow up of about 2.7 years occurred in 8.8% of cases and was associated with female gender. Further larger studies with longer follow up are needed to suggest time-frame for imaging follow up in order not to miss the enlargement of the adrenal masses that could require surgery and also to estimate possible enlargement prediction factors.