A clinicopathological analysis of adrenal tumors in patients with history of extra-adrenal cancers

Adrenal tumors in patients with previous/synchronous extra-adrenal malignancy are diverse and are a dilemma in clinical practice. This study investigated the differentiation of adrenal malignant and benign tumors in these patients. Data from patients with a pathological diagnosis of adrenal tumors were retrospectively retrieved from April 1991 to November 2015. Patients without extra-adrenal malignancy were excluded. Clinical and imaging characteristics, including sex, age, tumor size, tumor location, isolated lesion, time interval between the diagnosis of the two tumors and retrieved imaging diagnosis, were collected and analyzed. The selected patients were divided into 2 groups: those with primary or secondary malignancies (PSM) and those with primary benign tumors (PB). Chi-squared tests were used to evaluate differences between the two groups. Logistic regression was performed to explore potential risk factors related to the differentiation of PSM and PB, and a receiver operating characteristic (ROC) curve was used to evaluate their diagnostic values. Ninety-one patients were selected; 54 were male, and the median age was 56 years old. Between the groups of PSM and PB, sex (p = 0.004), age (p = 0.029), tumor size (p < 0.001), isolated lesion (p < 0.001) and imaging diagnosis (p < 0.001) were significantly different, while tumor size (p = 0.001), sex (p = 0.047) and imaging diagnosis (p = 0.002) were independent predictors of PSM. With ROC curve analysis, risk factors ≥2 was the optimal cutoff to differentiate these adrenal tumors, and their sensitivity and specificity were 73 and 77%, respectively. With a median follow-up of 32 months, only 4 of 32 patients with PB died from cancer, and 24 of 47 patients with PSM died from cancer, although aggressive treatment was performed. Tumor size, sex and imaging diagnosis were independent predictors of adrenal primary or secondary malignancies. These predictors might be helpful for differentiation of adrenal tumors in patients with previous/synchronous extra-adrenal cancers.