Adrenal Tumors Found During Staging and Surveillance for Colorectal Cancer: Benign Incidentalomas or Metastatic Disease?

Abstract

To evaluate the incidence of adrenal metastases in patient with colorectal cancer (CRC) and determine the clinical and radiographic features associated metastatic CRC to the adrenal glands. The review of consecutive adults with newly diagnosed CRC found to have adrenal tumors > 1cm in size on staging or surveillance CT scans with at least two scans to evaluate progression or stability of disease. Fifty-eight of 856 (6.8%) CRC patients had an adrenal tumor. Forty-three patients (74%) with 46 adrenal tumors had benign adrenal tumors, and 15 (26%) patients with 17 adrenal tumors had metastatic disease. On univariate analysis, patients with metastatic CRC had larger adrenal tumors (26.7mm vs 12.4mm, p < 0.01), a higher mean CEA (239ng/mL vs 14.2ng/mL, p = 0.03), and were more likely to have other sites of metastatic disease seen on imaging 8/43 (19%) vs 14/15 (93%), p < 0.01. On multivariable analysis, adrenal tumor size > 1.8cm (OR 49.6 CI 8-306), CEA > 2.5ng/mL (OR 15.8 CI 1.7-144) and other metastatic disease seen on imaging (OR 68.1 CI 7-661) were independently associated with adrenal metastases. CRC patients with small adrenal tumors, normal CEA levels and no evidence of other metastatic disease are unlikely to have spread to the adrenal glands. Adrenal tumors found during staging and surveillance of CRC patients should be evaluated with appropriate imaging and biochemical analysis.