Lessons from Natural Progression of an Adrenocortical Carcinoma Early Radiological Clues & Limitations of Biopsy

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: MON 1-36-Adrenal Incidentaloma & Carcinoma
Clinical
Monday, June 17, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board MON-32
Subramanian Kannan*1, Ankita Satra2, Kevin Parrack2, Eren Berber3, Christopher Przybycin2, Allan E Siperstein4 and Amir Hekmat Hamrahian1
1Cleveland Clinic Foundation, Cleveland, OH, 2Cleveland Clinic Foundation, 3Cleveland Clinic, Cleveland, OH, 4Cleveland Clinic Fndtn, Cleveland, OH
Background: Adrenocortical carcinoma (ACC) comprises of <5% of all adrenal incidentalomas (AI) (1). Most radiological features of ACC are described in large tumors with median size >6cm. The typical features of ACC include irregular shape and border, heterogeneous lipid poor mass, < 60% absolute (< 40% relative) delayed contrast washout) and it may contain areas of necrosis, hemorrhage and calcification. Needle biopsy is not recommended given the possibility of sampling error and the risk of needle track seeding (2, 3). We present a case of ACC, presenting as a small AI and highlight the early radiological clues and limitation of needle biopsy. 

Clinical case: A 54 year old woman underwent emergent appendectomy in Jan 2008. Pre-operative CT abdomen revealed a well defined, 2.6 cm irregularly shaped, right adrenal incidentaloma with a non-contrast CT attenuation of 35 HU and a focal speck of calcification. A follow up CT scan six months later showed stable size of the mass along with a 58% absolute and 41% relative delayed washout percentage. Work up for pheochromocytoma and Cushing syndrome was negative. In April 2009, she underwent a laparoscopic right adrenalectomy. Surgical pathology reported a normal adrenal gland with an adjacent area of mature adipose tissue consistent with a lipoma but did not recognize any adrenocortical tumors. A repeat CT abdomen performed in Oct 2012 for abdominal pain showed a 11 X 9 cm heterogeneously enhancing mass arising from the right adrenal bed with splaying the aorta and IVC with areas of necrosis. A CT guided core biopsy could not differentiate between benign and malignant adrenal neoplasm. Immunohistochemical stains of the tissue fragment was positive for inhibin, calretinin, vimentin and Melan-A, and negative for smooth muscle antigen or CD99 confirming the adreno-cortical origin of the tumor. On subsequent referral to our institution, surgical resection of the adrenal mass was aborted intra-operatively as the mass had invaded into the aorta and vertebrae. Patient is currently undergoing chemotherapy.

Clinical lessons: High pre-contrast attenuation value (>30 HU), focal calcification and irregular shape may be clues for an early underlying ACC. A lack of tumor growth during a short follow up period should not be used as an absolute evidence against an underlying ACC. CT guided biopsy may not differentiate between benign adenoma and ACC.

1. Barzon L, Sonino N, Fallo F, Palu G, Boscaro M. Prevalence and natural history of adrenal incidentalomas. Eur J Endocrinol. 2003 Oct;149(4):273-85. 2. Erozen YS. Fine needle aspiration cytology. In: Sidawy MK AS, editor. Kidney and Adrenal Gland. 1st ed. Philadelphia PA: Churchill Livingstone Elsevier; 2007. p. 299. 3. Lack EE WJ. Adrenal glands. In: Bostwick DG CL, editor. Urologic Surgical Pathology. 2nd ed. Mosby Elsevier; 2008. p. 952. 

Nothing to Disclose: SK, AS, KP, EB, CP, AES, AHH

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm