Abdom Imaging 18:95-96 (1993) Abdominal Imaging

�9 Springer-Verlag New York Inc. 1993

MR Imaging of Adrenal Lymphoma

F r e d T. L e e , J r . , J ohn R. T h o r n b u r y , T h o m a s M. Gr is t , and F r e d e r i c k K e l c z Department of Radiology, University of Wisconsin Hospital and Clinics, Madison, Wisconsin, USA

Abstract. A case o f l y m p h o m a of the ad r ena l g lands is p r e s e n t e d . B o t h c o m p u t e d t o m o g r a p h y (CT) and m a g n e t i c r e s o n a n c e imag ing (MRI) d e m o n s t r a t e d large b i l a t e ra l a d r e n a l m a s s e s wi th no o t h e r assoc i - a t ed a b d o m i n a l a b n o r m a l i t i e s . M R was b e t t e r ab le to d e m o n s t r a t e in fe r io r v e n a cava l p a t e n c y than CT, and e f f ec t ive ly e x c l u d e p h e o c h r o m o c y t o m a as a dif- f e ren t i a l d i a g n o s t i c c o n s i d e r a t i o n due to signal char - ac t e r i s t i c s o f the m a s s e s .

Key words: A d r e n a l l y m p h o m a , d i agnos i s - - A b d o - men , M R imaging.

M a g n e t i c r e s o n a n c e imaging (MRI) of the ad rena l g lands has p r o v e n usefu l for the c h a r a c t e r i z a t i o n o f a wide range o f a d r e n a l m a s s e s , inc lud ing p r i m a r y and m e t a s t a t i c n e o p l a s m s [1, 2]. A l t h o u g h the com- p u t e d t o m o g r a p h i c (CT) a p p e a r a n c e o f ad r ena l lym- p h o m a has b e e n d e s c r i b e d , w e have b e e n unab le to find a p e e r - r e v i e w e d l i t e r a tu re r e f e r e n c e de sc r i b ing the M R c h a r a c t e r i s t i c s . W e r e p o r t a c a se o f a d r e na l l y m p h o m a i m a g e d b y C T and M R I , and sugges t tha t l y m p h o m a shou ld be c o n s i d e r e d in the d i f fe ren t ia l d i agnos i s o f b i l a t e r a l a d r e n a l m a s s e s , e v e n in the a b s e n c e o f o t h e r s i tes o f l y m p h a d e n o p a t h y .

Case Report

A 55-year old man presented to his local physician complaining of worsening lower back pain. The patient had no significant past medical history with the exception of a 40-pack year smoking history. Conservative treatment was undertaken with no relief of pain over the following 2 months. The patient then returned to the hospital complaining of vomiting accompanied by abdominal pain radiating into the chest. ACT scan of the abdomen (Fig. 1A) was obtained (Somatom HiQ, Siemens Medical Systems, Inc., Iselin, NJ), which revealed large bilateral adrenal masses, and was fol-

Address offprint requests to: Fred T. Lee Jr., M.D., Department of Radiology, University Hospital and Clinics, 600 Highland Ave- nue, Madison, WI 53792-3252, USA

lowed by an MRI of the abdomen (0.5T GE Max, General Elec- tric, Milwaukee, WI) (Fig. 1B and C). The masses were of low signal intensity on Tl-weighted images, and high signal intensity compared to liver on T2-weighted images. The patient's wife had started to notice slurring of the speech and foregetfulness, and a CT scan of the head revealed findings consistent with an ependy- mal inflammatory process, suggesting carcinomatosis. The pa- tient was subsequently transferred to a tertiary care center for further evaluation.

Upon admission, the patient was found to be confused, with neurologic findings suggestive of midbrain and pontine lesions. No abdominal masses or peripheral adenopathy were detected by physical examination. MRI scan of the head revealed diffuse ep- endymal and meningeal enhancement as well as high signal in the midbrain consistent with diffuse metastatic involvement. Cere- bral spinal fluid was positive for malignant cells, type unknown, and a bone marrow biopsy was negative. The patient underwent percutaneous fine needle biopsy of the left adrenal gland under CT guidance, which was nondiagnostic. Core biopsy was deferred due to a grossly bloody aspirate from the fine needle aspiration, and the patient was referred for open surgical biopsy.

At surgery, there was no evidence of abdominal metastic dis- ease. A large right adrenal mass was excised, and noted to con- tain necrotic areas. The mass was found to extend under, but not invade, the inferior vena cava. A large mass was palpated involv- ing the left adrenal gland but was not biopsied. Histopathologic examination revealed a malignant lymphoma of follicular center cell origin.

The patient recovered from surgery, and was treated with intrathecal methotrexate and radiation therapy. During treat- ment, a progressive deterioration in neurologic and respiratory status culminated in respiratory collapse. The patient expired shortly thereafter, and autopsy was not permitted.

Discussion

Ima g ing o f the a d r e n a l g land is r o u t i n e l y p e r f o r m e d b y CT, u l t r a s o u n d , and o c c a s i o n a l l y nuc l e a r medi - c ine e x a m i n a t i o n [3, 4]. R e c e n t l y , M R I has been in- c r e a s ing ly u t i l i zed in a d r e n a l imaging and in some cases , such as p h e o c h r o m o c y t o m a , he lps to in- c r e a s e imag ing a c c u r a c y [5]. A l t h o u g h M R I images o f a d r e n a l l y m p h o m a h a v e b e e n p r e s e n t e d in tex t - b o o k s [6, 7], w e h a v e b e e n u n a b l e to f ind a r e p o r t in the p e e r - r e v i e w e d l i t e r a tu re , and thus p r e s e n t a re- cen t case .

96 F.T, Lee, Jr. et al.: Adrenal Lymphoma

Fig. 1, A C T scan through midabdomen shows large bilateral adrenal masses (*), upper pole of kidneys (arrow), and narrowed inferior vena cava (arrow- heads). B MR at approximately the same level with T1 weighting (TR-700, TE-25) demonstrates similar findings. Note flow void in the inferior vena cava (arrowheads). C T2-weighted MR image (TR-2500, TE-100). Again, note flow void in inferior vena cava (arrowheads) and increased signal inten- sity of adrenal tumors (*) compared to the adjacent liver.

This case had several unusual features which demonstrated the difficulty of distinguishing adrenal lymphoma from metastatic disease. No other ab- dominal lymphadenopathy was present which would have suggested the diagnosis of lymphoma [2], though adenopathy can certainly be present in meta- static disease. The signal characteristics of the masses were also nonspecific, although focal high- signal areas on T2-weighted images likely corre- sponded to necrotic tissue found at surgery. The predominant signal characteristics of the masses were low on T1 and moderately high signal on T2 in relation to liver, similar to that expected for meta- static disease [8]. The T2 signal intensity was higher than that of fat, contrary to other experience [6].

A second feature in this case bears note. CT im- ages demonstrated anterior displacement and nar- rowing of the vena cava by the right adrenal mass. Despite an excellent contrast bolus, it is difficult to assess caval patency with confidence by CT alone (Fig. IA). MR images demonstrate flow void in the vena cava on all slices, assuring vascular patency.

The presented case highlights the fact that the differential diagnosis of bilateral adrenal masses should include lymphoma, even in the absence of other adenopathy. Although no specific signs of lyre-

phoma by MR imaging were encountered in this case or have been reported, MR can still prove useful in the evaluation of bilateral adrenal masses, specifi- cally to help exclude pheochromocytoma, and to as- sess regional vascular patency.

References

1. Moon KL, Hricak H, Crooks LE. Nuclear magnetic resonance imaging of the adrenal gland: a preliminary report. Radiology 1983;147:155-160

2. Dnnnick NR. Adrenal imaging: current status. A JR 1990; 154:927-936

3. Glazer GM, Francis IR, Quint LE. Imaging of the adrenal glands. Invest Radiol 1988;23:3-11

4. Yeh HC. Ultrasonography of the adrenals. Semin Roentgenol 1988;23:250

5. Reinig JW, Doppman JL, Dwyer AJ, et al. Adrenal masses differentiated by MR. Radiology 1986;158:81-84

6. Lee JKT, Sagel SS, Stanley RJ. Computed body tomography with MRI correlation (2nd ed.). New York: Raven Press, 1989, p 844

7. Stark DD, Bradley WG. Magnetic resonance imaging. St. Louis: C.V. Mosby Company, 1988, p 1183

8. Glazer GM. MR imaging of the liver, kidneys, and adrenal glands. Radiology 1988;166:303-312

Received: August 22, 1992; accepted: September 15, 1992