A 13-year old pre-menarchal girl, with features of excess acne and hirsuitism

A 13-year old pre-menarchal girl, with features of excess acne and hirsuitism

A 13-year old pre-menarchal girl, with features of excess acne and hirsuitism

  • Ultrasound demonstrates a uniformly hypoechoic right suprarenal mass.
  • CECT Abdomen and Pelvis coronal image demonstrates a well-defined homogeneously enhancing mass lesion (~7 cm in size) arising from the right adrenal gland and indenting the right kidney and liver with no infiltration into adjacent structures.
  • Non-contrast axial images demonstrate increased attenuation of adrenal lesion measuring 45 HU with further axial arterial, venous, and 15-minute delayed images demonstrating Absolute Percentage Washout (APW) of 75 % and Relative Percentage Washout (RPW) of 43 %.
  • On MRI, In and Out of phase images, no significant chemical shift artifact was observed.
  • Gross pathology post-operative specimen shows a smooth encapsulated mass.
  • HPE – The tumor is composed of cells with pink cytoplasm and focal cells with clear cytoplasm. The cells are arranged in nests and show significant nuclear pleomorphism with a few cells showing large bizarre nuclei and prominent nucleoli. Apoptosis and occasional mitoses were seen. There is no capsular/ vascular invasion. No necrosis was seen.


Lipid poor functioning right adrenal cortical adenoma.


  • Most adrenal lesions are non-functional and benign, and are usually incidentally diagnosed. Only a small number of adrenal tumors are functional and even smaller number are malignant lesions.
  • Functioning adrenal lesions can be:
  1. Adrenal cortex – Adrenal cortical hyperplasia, Adrenal adenoma, Aldosteronoma or Adrenal cortical carcinoma.
  2. Adrenal medulla – Phaeochromocytoma.
  • In this case, blood parameters demonstrated increased cortisol levels and increased male hormonal levels (androgen) suggesting a dual hormone secreting adrenal lesion.
  • No cushingoid features or abnormal blood pressure.

Lipid Poor Functioning Adrenal Adenoma:

  • Characterisation of adrenal adenomas can be based on anatomical features i.e, increased intracellular lipid content (Average < 10 HU) and physiologic vascular enhancement pattern using dynamic contrast protocol demonstrating an APW > 60%, which has a sensitivity of 88 % and specificity of 96 %, and RPW > 40 %, which has a sensitivity of 83 % and specificity of 93 %.
  • Nearly 30 % of adenomas lack sufficient intracellular lipid content and if non contrast CT demonstrates a HU value of > 20 -30 HU, chemical shift MR imaging may be less useful in arriving to a diagnosis of an adenoma.
  • Delayed (15 min) enhanced CT can help characterize hyperattenuating adrenal masses that cannot be characterized with chemical shift MR imaging.

Differential diagnosis:

  1. Adrenal cortical carcinoma: Large irregular heterogenous mass with necrosis and infiltration adjacent structures.
  2. Phaeochromocytoma: Intense enhancement in arterial phase, demonstrates washout pattern similar to adenoma and appears as T2 hyperintense lesion (lightbulb sign) on MRI.
  3. Adrenal metastases.



  1. Albano D, Agnello F, Midiri F, et al. Imaging features of adrenal masses. Insights Imaging. 2019;10(1):1. Published 2019 Jan 25. doi:10.1186/s13244-019-0688-8
  2. Caoili EM, Korobkin M, Francis IR, Cohan RH, Dunnick NR. Delayed enhanced CT of lipid-poor adrenal adenomas. AJR Am J Roentgenol 2000;175:1411–1415.
  3. Park, B. K., Kim, C. K., Kim, B., & Lee, J. H. (2007). Comparison of Delayed Enhanced CT and Chemical Shift MR for Evaluating Hyperattenuating Incidental Adrenal Masses1. Radiology, 243(3), 760–765. doi:10.1148/radiol.2433051978

Dr. Diwakar C
Radiology Resident,
Manipal Hospitals Radiology Group.

Dr. Vivek Jirankali MD,
Senior Resident and Cross-Sectional Fellow,
Manipal Hospitals Radiology Group.