Skeletal Radiol. 2, 254-257 (1978) Skeletal Radiology

Case Report 56

R i c h a r d G o r d o n , M . D . , A k b a r B o n a k d a r p o u r , M . D . * , R e n a t e Sou len , M . D . , a n d R o b e r t O. Pe te r sen , M . D .

Departments of Radiology and Pathology, Temple University School of Medicine and Hospital, Philadelphia, Pennsylvania, USA

Fig. 1. A An anteroposterior film of the lumbar spine shows a poorly-defined, expanding, lytic area involving the body of L4, more prominent on the left (stereoscopic studies in the AP plane aided in the delineation of the lyric lesion). Degenerative changes of the lumbar spine are present. B An anteroposterior laminagram illustrates strikingly the expanding, lytic lesion of the body of the 4th lumbar vertebra

* Presented by Dr. Akbar Bonakdarpour at the 2nd Annual Meeting of the International Skeletal Society in London, England, April 25th-27th, 1975

Address reprint requests to." A. Bonakdarpour, M.D., Department of Radiology, Temple University School of Medicine and Hospital, 3401 North Broad Street, Philadelphia, PA 19140, USA

0364-2348/78/0002-0254 $01.00 �9 1978 I n t e r n a t i o n a l Ske le ta l Soc ie ty

R. Gordon et al.: Case Report 56 255

History

A 49-year-old white man had compla ined of inter-

mi t tent back pain since chi ldhood. Three weeks pr ior

to admiss ion the pain recurred, but became more

severe and persistent and was localized to the left

side of the back between the L 2 and L 4 vertebrae.

Physical examina t ion showed approx imate ly 50 per-

cent l imi ta t ion of flexion and extension of the spine.

All l abora to ry findings were normal . A rad ionucl ide

scan was normal . Plain film radiological studies, as

well as t o m o g r a p h y and angiography, were obtained.

A needle biopsy of the 4th lumbar ver tebral body was performed.

Fig. 1 C. A lateral roentgenogram of the lumbar spine shows the lyric area in the body of L4, but not as dearly as in the frontal plane films. Incidentally observed is a defect in the anterosuperior surface of the body of L 3 which is probably a Schm6rl's node and not related to the abnormality of L4

Figs.2A and B. The arterial and capillary phases in these antero- posterior angiograms show no abnormal or increased vascularity in the area of L4. A bone scan using Tc 99m pyrophosphate was within normal iimits

256 R. Gordon et al. : Case Report 56

Histological Section

Fig. 3. A high-power photomicrograph from the specimen obtained on the needle biopsy of the fourth lumbar vertebral body (H and E stain x 680) shows numerous plasma cells evidencing variable differentiation characterized by variations in nuclear size and the amount of cytoplasm

Diagnosis: Plasmacytoma of L 4

The differential diagnosis must include a metastatic lesion, chordoma, reticulum cell sarcoma, and several less likely benign disorders, e.g. aneurysmal bone cyst, osteoblastoma and even fibrous dysplasia. An infec- tive lesion is highly unlikely.

Discussion

Plasmacytoma is not infrequently the initial mani- festation of multiple myeloma, although to be sure, a large number of individuals present with the full- blown disorder with multicentric lesions. Myeloma is a malignant neoplastic disorder, arising in the prim- itive marrow and tending as a rule to remain confined to the skeleton, but, on occasion, affecting extraskele-

tal structures. Most plasmacytomas affect the spine, innominate bones and ribs, not infrequently remain- ing as isolated lesions for months and even years. Ultimately, however, in virtually all instances, the patient will develop generalized manifestations of multiple myeloma.

The age of predilection is from the fifth to the seventh decades, with very few cases being en- countered below the age of 40 years. Men are affected somewhat more frequently than women in the propor- tion of about 3 to 2. Pain in the back is a very common initial complaint, although weakness, loss of weight and anemia may be presenting features.

Pathologically, the marrow in the area of the skele- tal lesion is replaced by sheets of myelomatous tissue which thin and actually destroy bone trabeculae. Thinning of the cortices, with considerable destruc- tion of the cortical and periosteal layers in the later stage, is characteristic. Discrete hemorrhagic and cys- tic tumor masses, particularly in plasmacytoma, may be encountered.

The myeloma tissue itself is generally highly cellu- lar with a fairly uniform pattern of spheroid cells, which, on occasion, vary in size and infrequently con- tain eccentric nuclei. Tumor giant cells may be pres- ent. New bone formation, although very rare, may occur even in plasmacytoma.

Laboratory findings are generally specific. The blood serum protein is often elevated, with the albu- min-globulin ratio frequently reversed. Hypercalce- mia is often present. Bence-Jones protein in the urine may be detected in about 60 percent of patients with myelomatosis, but less often in plasmacytoma. A characteristic " M " spot is usually identified in the electrophoretic pattern of the serum. Sixty percent of patients with myeloma will show a monoclonal IgG spike in the serum. The next most common ab- n o r m a l i t y - a n IgA sp ike-occurs in more than 20 percent of the cases. Increase in IgD, IgE and IgM is rare in myeloma. In approximately 10 to 15 percent of cases an abnormal accumulation of im- munoglobulin will be absent.

Plasmacytoma (and myeloma) occur when an ab- normal clone of plasma cells (which are specialists of the B cell system) proliferates. Plasma cells, both in myeloma and the solitary phase of plasmacytoma, will comprise more than fifteen percent of nucleated cells on needle aspiration biopsy. Myeloma cells themselves may be morphologically indistinguishable from normal plasma cells, but pleomorphism, in- creased mitotic activity and immaturity are commonly observed. Osteoclastic activity is associated with nests of plasma cells which produce an osteoclast-stimulat- ing factor contributing to the destruction of bone.

R. Gordon et al. : Case Report 56 257

The radiological features of plasmacytoma are usually those of an expanding, aggressive, lytic lesion, with a wide zone of transition around its margins, An accompanying soft tissue mass may be large, par- ticularly when associated with a plasmacytoma of the rib. In this connection, the commonest cause of an extrapleural mass in the chest, past the age of 40 years, is plasmacytoma or one of the lesions of generalized myeloma. Plasmacytoma of the spine usually affects the vertebral body, but an appendage may also be involved. Compression fractures are com- mon and paraspinal masses are frequently en- countered. On myelography, extradural defects and even complete extradural blocks are not unusual.

This case demonstrates several interesting fea- tures. In the first instance, the lesion was best identified by stereoscopic anteroposterior views of the lumbar spine. Also of interest is the fact that a radionu- clide scan was normal. The angiographic findings in this case are interesting. The lesion was avascular, with no tumor vessels demonstrated. This feature en- abled the physician-in-charge to perform a needle biopsy rather than an open biopsy, since the possibil- ity of excessive bleeding was feared.

The place of angiography in the work-up of neo- plasms of bone is controversial; this procedure has not gained widespread acceptance. A total of 16 cases of plasmacytoma studied with angiography has been reported in the English literature. Of these, 13 affected bone and 3 were extra-osseous. Eleven lesions involved the calvarium and five cases were extracra- nial. All extracranial lesions were avascular, except for one which was previously treated by radiation therapy.

The debate over the use of angiography in the diagnosis of bone tumors centers over its intended purpose. Many investigators have found angiography valuable, because a large majority of malignant tu- mors studied with angiography proved to be highly vascular, with tumor vessels frequently identified.

However, other workers have reported that the ra- diological features on angiography are variable and inconstant and that some malignant lesions on occa- sion show a benign appearance arteriographically and benign lesions may actually show hypervascularity and even suggestive tumor vessels. Another problem lies in the fact that histologically different tumors at times have similar angiographic characteristics and that the same neoplasm may show different an- giographic patterns in different patients.

Halpern and Freiberger believe that arteriography can be helpful for certain limited purposes. These authors and Voegeli and Uehlinger are of the opinion that arteriography may be important in demonstrat- ing the optimal area for biopsy, the extent of the tumor both in bone and in soft tissues, the demonstra- tion of recurrence and even in preparing plans for radiotherapy.

In this case, angiography was helpful in determin- ing the type of bone biopsy to perform. Because the lesion proved to be avascular on angiography, it was not necessary to perform an open biopsy, so that a less traumatic needle biopsy could be utilized.

References

1. Halpern, M., Freiberger, R.: Arteriography as a diagnostic procedure in bone disease. Radiol. Clin. North Am. (1970)

2. Kutcher, R., Shatak, N.R., Leeds, N.E.: Plasmacytoma of the calvaria. Radiology 113, 111 (1974)

3. Sayre, R., Costellino, R.: Extramedullary plasmacytoma: an- giographic findings. Radiology 99, 329 (1971)

4. Steinbach, H.: Angiography of Bones and Joints. In: Abrams, H. : Angiography, VoI. II, p. 1306. Boston: Little, Brown & Co. 1971

5. Voegeli, E., Uehlinger, E. : Arteriography in bone tumors. Skele- tal Radiol. 1, 3 (1976)

6. Yaghmai, I., Shamsa, Az., Shariat, S., Afshari, R.: Value of arteriography in the diagnosis of benign and malignant bone lesions. Cancer 27, 1134 (I971)