An Adrenocortical Carcinoma Evolving After Nine Years of Latency From a Small Adrenal Incidentaloma

Abstract

Adrenal incidentalomas (AIs) are common incidental findings in medical practice with clinical significance. Although most AIs are nonsecretory and nonmalignant, they require a short course of follow-up over one to two years to rule out malignancy or hormonal secretion according to clinical practice guidelines. However, this can result in some adrenocortical carcinomas (ACCs) being missed if they transform at a later stage or evolve slowly. Here, we report one such case of an AI, which although remained indolent, eventually transformed into an ACC many years after the initial detection.

Transformation of a Benign Adrenocortical Adenoma to a Metastatic Adrenocortical Carcinoma Is Rare But It Happens

“…The transformation of an initially denoted ACA to ACC has been described not only with respect to imaging characteristics but also their hormonal profile. Five tumors initially characterized as nonfunctioning ACAs transformed to cortisol-secreting ACCs similar to our case ( 6 , 7 , 10 , 12 , 13 ).…”

“…In contrast to a previous retrospective study ( 17 ), ACCs found incidentally were less aggressive, presenting also better prognosis compared with the symptomatic ones ( 25 ). The clinical history of the 10 cases initially diagnosed as benign ACAs showed that only half were completely asymptomatic and could be characterized as “true AI.” In 3 patients ( 7 , 9 , 12 ) as in our case, a pre-existing atypical abdominal symptom led to the performance of further imaging, whereas in 1 case, this information was not available ( 11 ).…”

“…All cases were initially evaluated with a CT scan, and in 3 cases an MRI was additionally performed ( 6 , 11 , 13 ). Six cases had typical characteristics of ACAs on CT scan exhibiting low unenhanced attenuation values of <10 HU ( 5 , 7 , 8 , 9 , 10 , 11 ) whereas in the remaining 3 ( 6 , 12 , 13 ), the findings were ambiguous ( Table 2 ).…”

“…Recently, it was shown that a growth rate of 3 mm/year could distinguish ACA from malignant lesions with 100% sensitivity and specificity ( 18 ). However, 7 cases in the literature presenting initially with ACAs that remained stable in size for the first 5 to 7 years were diagnosed as ACCs after 7 to 10 years from the initial diagnosis of ACAs ( 5 , 7 , 8 , 10 , 11 , 12 , 13 ). Thus, surveillance with imaging during only the first 5 years from initial diagnosis would have missed the malignant transformation of these ACAs to ACCs.…”

Exploratory Circular RNA Profiling in Adrenocortical Tumors

“…According to our study, it might thus be hypothesized that circPHC3 could be associated with adrenal tumor formation irrespective of its benign or malignant behavior, and its altered expression could represent a common phenomenon in both benign and malignant adrenocortical tumors [ 20 ]. However, based on epidemiological observations, benign-to-malignant progression in the adrenal cortex could be a very rare event, and it is unlikely to account for the vast majority of ACC [ 50 , 51 , 52 , 53 ]. Thus, the biological relevance of our observation is unclear.…”