Case 12
History:
45 year old female with Cushing's syndrome
Findings:
Axial T2WI demonstrate a heterogenously bright right adrenal lesion, showing heterogenous enhancement after contrast administration.
Diagnosis:
Adrenal carcinoma (Pathologically proven)
Discussion:
Adrenal carcinoma (AC) are rare, highly malignant tumors with a poor prognosis.
- 20% non functioning. 50% hyperfunctioning.
- Size usually >5 cm
- Frequently heterogenous with irregular margins
- Occasionally calcified
- Tendency to IVC invasion
- Metastases to regional nodes, kidneys, liver, lung, bone, brain
- Mets are the only reliable sign of malignancy.
- Large size and calcifications are suggestive of it.
MRI shows heterogenous hyperintense lesion with heterogenous enhancement. According to early studies, high glucose uptake on FDG-PET scans suggests malignancy.
With regard to CT and adrenal masses, unenhanced density values of >10 HU are characteristic of adenomas with a high lipid content and this threshold has a sensitivity of 71% and a specificity of 98% in diagnosing such lesions. Adrenal lesions with a density of >10 HU in an unenhanced CT scan or an enhancement washout of <50% and a delayed attenuation of >35 HU are suspicious for malignancy.
References:
- Allolio B, Fassnacht M (2006). "Clinical review: Adrenocortical carcinoma: clinical update". J Clin Endocrinol Metab 91 (6): 2027–37
- Wajchenberg BL et al. (2000) Adrenocortical carcinoma: clinical and laboratory observations. Cancer 88: 711-736.
