Early radiological clues in diagnosis of adrenocortical carcinoma: lessons from a missed opportunity
Subramanian Kannan · Allan Siperstein · Amir H. Hamrahian
Received: 27 April 2013 / Accepted: 4 May 2013 @ Springer Science+Business Media New York 2013
Case presentation
A 54-year-old woman found to have a 2.6-cm irregularly shaped, right adrenal incidentaloma (AI) during work up for appendicitis. The mass had a non-contrast CT attenu- ation of 35 HU and a focal speck of calcification (Fig. 1a). A follow-up CT scan 6 months later showed a stable size adrenal mass with a delayed absolute and relative washout of 58 and 41 %, respectively. Work up was negative for hormonal hypersecretion. Patient underwent right adre- nalectomy. Unfortunately the mass was not resected along with the right adrenal gland. The surgical pathology reported a normal adrenal gland with an adjacent area of mature adipose tissue consistent with a lipoma. This lipo- matous tissue was assumed to be the visualized adreno- cortical tumor and patient was discharged from clinical care. A repeat CT abdomen, 4 years later for unrelated reasons, showed 11 cm x 9 cm heterogeneously enhanc- ing mass arising from the right adrenal bed with areas of necrosis (Fig. 1a) and patient was referred to our institu- tion. The surgical resection of this mass was aborted intra- operatively as it had invaded the aorta and vertebrae. Core biopsies confirmed the adrenocortical neoplasm (Fig. 1b) and given its clinical behavior is consistent with adreno- cortical carcinoma. Pathology slides from the previous institution were reviewed and it was confirmed that the original specimen did not contain the tumor.
Discussion
AI offers a rare opportunity to diagnose adrenocortical carcinoma (ACC) at an earlier stage amenable to curative resection. Radiological features of early (small) ACC are rarely reported in literature [1]. There are several important points about this case which may help clinicians appro- priately refer AI to the surgeon even if it does not meet the size criteria. High pre-contrast attenuation value (>30 HU), focal calcification and irregular shape, and ill-defined borders may be clues for early diagnosis of ACC. A lack of tumor growth during a relatively short follow-up period may not rule out an underlying ACC [2]. Absolute and relative wash out greater than 60 and 40 % at 15 min are reported to differentiate between adenomas and non-ade- nomas [3], however, these criteria may overlap between benign adenomas and early stages of ACC as described in this case. Finally, it is important to review the pathology information with respect to the pre-operative radiological information. While the pre-operative imaging suggested a lipid poor mass, the pathology suggested a lipoma. This could have been the tip-off for the treating team to re- image the patient post-operatively and remove the actual tumor.
S. Kannan () . A. Siperstein . A. H. Hamrahian ☒ Endocrinology and Metabolism Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Desk F20, Cleveland, OH 44195, USA
e-mail: kannans@ccf.org
a
Initial non- contrast CT scan
MPORT -NBNR 4
Contrast enhanced CT scan 6 mon later
IVC
A
Aorta
Contrast enhanced CT scan 4 years later
b
Acknowledgments The authors thank Dr. Christopher Przybycin from Department of Anatomic Pathology, Cleveland Clinic for pro- viding the pathology images.
Disclosures The authors have nothing to disclose and no conflict of interest. This case has been accepted as an abstract for poster pre- sentation at the Endocrine Society Meeting 2013.
References
1. C.C. Barnett Jr., D.G. Varma, A.K. El-Naggar, A.P. Dackiw, G.A. Porter, A.S. Pearson et al., Limitations of size as a criterion in the
IVC. b Core biopsy of the tumor performed intra-operatively: H&E stain magnification ×20 shows round to oval cells, with scant eosinophilic cytoplasm and inset showing positive immunostains [Calretinin (top) and Inhibin (bottom)] confirming the adrenal origin of the tumor
evaluation of adrenal tumors. Surgery 128(6), 973-982 (2000). discussion 982-983
2. K.M. Pantalone, T. Gopan, E.M. Remer, C. Faiman, A.G. Ioachimescu, H.S. Levin et al., Change in adrenal mass size as a predictor of a malignant tumor. Endocr. Pract. 16(4), 577-587 (2010)
3. E.M. Caoili, M. Korobkin, I.R. Francis, R.H. Cohan, J.F. Platt, N.R. Dunnick et al., Adrenal masses: characterization with combined unenhanced and delayed enhanced CT. Radiology 222(3), 629-633 (2002)