Whole-Body Positron Emission Tomographic Scanning in Patients with Adrenal Cortical Carcinoma Comparison with Conventional Imaging Procedures
MOHAMMED AHMED, F.A.C.P.,* ABDULAZIZ AL-SUGAIR, M.D.,t
ABDULLAH ALARIFI, F.R.C.P.,* ABDULRAOF ALMAHFOUZ, M.D.,* AND SAIF AL-SOBHI, F.R.C.S.#
Two patients with histologically documented adrenal
cortical carcinoma (ACC) underwent whole-body fluoro-
deoxyglucose (FDG) positron emission tomographic
(PET) imaging. Results were compared with those of
computed tomography (CT), magnetic resonance imag-
ing (MRI), ultrasound, bone scanning, and octreotide im-
aging to evaluate the role of PET and to determine any
additional advantage PET may provide over conven-
tional imaging in the management of ACC. Both patients
were 26-year-old men. One patient was found to have
Cushing’s syndrome, and the other had a clinically silent
recurrent ACC. These findings indicate that PET can
accurately localize ACC before operation and reliably
detect its recurrence after operation. It can serve as an
adjuvant imaging method in the detection of metastases
and monitor the clinical course of ACC with findings that
complement those of conventional imaging. It can yield
additional information in defining tumor metabolic activ-
ity, necrosis, and in the earlier detection of metastases
compared with CT.
The authors thank Precy Manahan-Vidonia for secretarial support.
Received for publication July 1, 2002. Revision accepted November
18, 2002.
Reprint requests: Mohammed Ahmed, Department of Medicine
(MBC-46), King Faisal Specialist Hospital & Research Centre, P. O.
Box 3354, Riyadh 11211, Saudi Arabia. E-mail: ahmed@kfshrc.edu.sa
References
1. Huvos AG, Hadju SI, Brasfield RD, et al: Adrenal cortical carci-
noma: clinicopathologic study of 34 cases. Cancer 25:354, 1970.
2. Hajjar RA, Hickey RC, Samaan NA: Adrenal cortical carcinoma.
Cancer 35:549, 1975.
3. Schteinghart DE: Cushing syndrome. In: Becker KL, ed. Principles
and Practice of Endocrinology and Metabolism. Philadelphia:
JB Lippincott, 2001, pp 723-37.
4. Lee MJ, Hahn PF, Papanicolaou N, et al: Benign and malignant
adrenal masses: CT distinction with attenuation coefficients,
size, and observer analysis. Radiology 179:415, 1991.
5. Schlund JF, Kenney PJ, Brown ED, et al: Adrenocortical carci-
noma: MR imaging appearance with current techniques. J
Magn Reson Imaging 5:171, 1995.
6. Kunishima S, Taniguchi H, Yamaguchi A, et al: Evaluation of
abdominal tumors with [F- 18] fluorodeoxyglucose positron
emission tomography. Clin Pos Imag 3:91, 2000.
7. Strauss LG, Conti PS: The applications of PET in clinical oncol-
ogy. J Nucl Med 32:623, 1991.
8. Mijin Y, Woojin K, Naheel A, et al: F-FDG PET in characterizing
adrenal lesions detected on CT or MRI. J Nucl Med 42:1795,
2001.
9. Maurea S, Mainolfi C, Bazzicalupo L, et al: Imaging of adrenal
tumors using FDG PET: comparison of benign and malignant
lesions. AJR Am J Roentgenol 173:25, 1999.
10. Boland GW, Goldberg MA, Lee MJ, et al: Indeterminate adrenal
mass in patients with cancer: evaluation at PET with 2-[F-18]-
fluoro-2-deoxy-D-glucose. Radiology 194:131, 1995.
From the Departments of Medicine,* Radiology,t and
Surgery,# King Faisal Specialist Hospital and Research
Centre, Riyadh, Saudi Arabia
Fig. 1. ACC generally presents as a large abdominal tumor with metastases characterized by a progressive course and poor prognosis (1-3). The disease can be hormonally active or clinically silent. Patients' clinical course and response to treatment are monitored by hormonal evaluation and different imaging methods, the latter being most relevant for clinically silent tumors (1-3). Imaging techniques that have been used to localize the primary tumor and its metastases include CT, MRI, and ultrasonography. Adrenal scintigraphy using 6-ß I-131 iodomethyl-19-norcholesterol has also been used for the differential diagnosis of adrenal tumors (3). MRI and CT scanning are important imaging methods in the evaluation of adrenal tumors (4,5) (A) In patient A, MRI of the abdomen (coronal image) shows a large (17.5 x 11.5 cm), oval-shaped, well-defined right retroperitoneal mass. It is mainly of solid texture with multiple areas of central necrosis (hyperintense in this T2 weighted image; hypointense in a T1 weighted image that is not shown).
A
B
(B) A CT scan of the abdomen (axial view, contrast enhanced) shows a large right adrenal mass with a maximal diameter of 17 x 12 cm
and a craniocaudal extension of 18 cm indenting the right lobe of the liver, but the latter shows no parenchymal lesion.
Fig. 2. A CT scan of the chest (axial view, contrast enhanced) in patient A shows a right posterior lung nodule (arrow).
R
Fig. 3. Abdominal ultrasound in patient A. (A) Sagittal and (B) transverse views show a large right upper quadrant mass indenting the right lobe of the liver (arrows). The arrowhead indicates a hyperechoic, oval-shaped (3 x 1.3 cm) lesion in the liver surrounded by a hypoechoic rim.
A
B
Fig. 4. PET was performed in patient A after administration of FDG, which is useful in de- tecting a wide variety of tumors (6,7). Many malignant tumors actively take up FDG, which is evidence of enhanced glycolysis compared with the surrounding benign tissue (7). ACCs are metabolically active tumors, and it would be of interest to determine the ability of these tumors and their metastases to concentrate FDG. Indeed, FDG PET can be valuable in characterizing adrenal lesions detected on CT or MRI (8,9) and in evaluating indeterminate adrenal masses in persons with cancer (10). (A) A whole-body FDG-PET scan (coronal view) shows an intensely hypermetabolic tu- A B mor of the right adrenal with central necrosis, corresponding to the findings on MRI and the CT scan. The arrow indicates a focus of FDG uptake in the right lobe of the liver that failed to be seen on CT but was seen on the US in Figure 3A. (B) An FDG-PET scan (transaxial view) again shows the hypermetabolic focus in the right lobe of the liver (arrowhead) that corresponded to the lesion seen on the ultrasound image in Figure 3A but was not seen on the CT scan. The arrow shows the lesion in the right lower lung field corresponding to that seen on the CT scan in Figure 2.Fig. 5. A CT scan (axial views: noncontrast enhanced) in patient B shows a 2.5-cm nodular density (arrow) medial to the atrophic left kidney and another 6-x-2-cm mass lesion (arrowheads) abutting the left kidney behind the stomach, representing recurrent adrenal cortical carcinoma.
A
B
Fig. 6. A CT scan of the chest (lung window, without contrast enhancement) in patient B shows a 9-mm nodule (encircled) in the left posterior lung field.
R
1
RK
LK
A
Fig. 7. (A) A whole-body FDG-PET scan in patient B. A coronal view shows a hyper- metabolic focus of FDG uptake (arrow) in the left upper abdomen corresponding to the nodular lesion of the recurrent adrenal carci- noma seen in Figure 5 and relatively faint up- take in the left lung field (arrowhead) corre- sponding to the lesion seen on the CT scan in Figure 6. RK, right kidney; LK, atrophic left kidney. (B) An FDG-PET scan (axial view) shows two intensely hypermetabolic foci of recurrent adrenal carcinoma (the arrow corre- sponds to the nodular lesion and the arrow- head corresponds to the left juxtarenal lesion seen in Fig. 5.
RK
LK
B
Fig. 8. A whole-body FDG-PET scan (sagittal view) in patient B shows intensely hypermetabolic foci (arrows) in the spine (T9 and T10 vertebral bodies, likely representing metastases) that were not evident on octreotide and CT images.