Risk of adrenocortical carcinoma in adrenal tumours greater than 8 cm.

BACKGROUND: Adrenocortical cancer (ACC) is a rare malignancy. In the absence of metastatic disease, the suspicion of ACC is based on size and radiological appearance. The aim of this study was to analyse the long-term outcome of patients with large adrenal cortical tumours (>8 cm).

METHODS: A prospective database recorded clinical, biochemical, operative and histological data on patients operated for cortical adrenal tumours between January 2000 and February 2013. Out of 130 patients operated for cortical adrenal tumours, analysis was restricted to 37 cortical tumours >8 cm.

RESULTS: There were 31 (84 %) ACCs and 6 (16 %) benign adenomas (p < 0.01). The most common presentation was that of an abdominal mass [17 (55 %) vs. 3 (50 %), ACC vs. benign, respectively]. There was no difference in size between stage II and stage III-IV tumours; however, there was a trend for tumours to be heavier in advanced stages (920 ± 756 vs. 1,435 ± 1,022 g, p = 0.08, stage II vs. stage III-IV, respectively). No mortality was observed in patients with benign tumours during a median follow-up of 70 months (range 36-99 months). Mortality in the ACC group occurred in 17/31 (55 %) patients. Mitotane was administered in 12 (71 %) patients with stage III-IV ACCs with a 5-year survival rate 25 % compared to 20 % in patients who did not receive Mitotane. In stage II ACC, eight (57 %) patients received Mitotane with a 50 % mortality at 5 years.

CONCLUSIONS: The high incidence of ACC in cortical tumours >8 cm underlines the need for adequate surgical resection via open surgery aiming to avoid local recurrence. Beyond surgery, the impact of other therapies is not fully characterised and the efficacy of adjuvant Mitotane treatment is yet to be proven.