Primary leiomyosarcoma of the abdominal aorta

CASE REPORTS

Primary leiomyosarcoma of the abdominal aorta Michael D. Malone, MD, Karolyn Kerr, MD, Maureen Kavanah, MD, and J a m e s O . M e n z o i a n , M D , Boston, Mass. Primary malignancies o f the aorta are extremely rare. A review o f the literature indicates t h a t 35 d o c u m e n t e d cases o f primary t u m o r s o f the aorta have been r e p o r t e d over the past 120 years. The histologic and m o r p h o l o g i c characteristics o f these lesions may be variable. I n this case, progressive claudication o f the left leg and buttocks w i t h absent femoral pulses in a middle-aged w o m a n was f o u n d to be a primary leiomyosarcoma o f the a b d o m i n a l aorta. A magnetic resonance imaging study defined a retroperitoneal space-occupying mass o n the left side o f the a o r t a at the level o f the f o u r t h l u m b a r vertebrae. A magnetic resonance angiographic scan o f the a b d o m i n a l aorta and an a o r t o g r a m revealed total occlusion o f the distal a b d o m i n a l a o r t a with reconstitution at the level o f the c o m m o n femoral arteries bilaterally, w i t h n o r m a l vessels m o r e distal to t h a t region. The patient u n d e r w e n t surgical exploration and resection o f the retroperitoneal, infrarenal, occluding aortic mass. The mass was f o u n d to be a high-grade sarcoma displaying s m o o t h muscle cell differentiation. The resection o f this lesion, perioperative management, and pathologic characteristics o f a rare primary neoplasm o f the a o r t a are discussed in this review. (J Vase Surg 1996;24:487-93.)

CASE R E P O R T A 51-year-old woman from India with no significant medical history had had claudication of the left leg and buttock for 6 months. The patient's symptoms had been worsening, actually awakening her from sleep at times because of a dull, chronic ache in the left buttock. The patient's initial work-up consisted of an abdominal ultrasound scan, which showed a hypoechoic mass (2.4 x 2.6 cm) on the left lateral side of the aorta. The patient then underwent magnetic resonance imaging (MR/) of the abdomen, which showed at the level ofT1 weighted images, an ill defined isodense to hypodense retroperitoneal spaceoccupying lesion on the left side of the aorta at the level of the third and fourth lumbar vertebrae, above the level of the aortic bifiarcation. The initial interpretation of these data was suggestive of an abdominal aortic aneurysm with slow flow and the possibility of dissection. The patient then was referred for further evaluation to From the Department of Surgery, Sections of VascularSurgery and Section of Surgical Oncology (Dr. Kavanah), Boston University School of Medicine. Reprint requests: James O. Menzoian, MD, Department of Surgery, Boston University Medical Center, 88 East Newton St., Boston, MA 02118. Copyright © 1996 by The Society for Vascular Surgery and International Society for Cardiovascular Surgery, North American Chapter. 0741-5214/96/$5.00 + 0 2 4 / 4 / 7 1 9 3 9

the vascular clinic at Boston University Medical Center. At the initial physical examination, the patient was noted to be a well-nourished, middle-aged woman who appeared her stated age and appeared to be in no acute distress, Her vital signs included a blood pressure of 1 2 4 / 7 6 mm H g that was symmetrical in both arms, with a pulse of 72 beats per minute. No carotid bruits or abdominal bruits were noted. The examination of the patient's abdomen revealed no abnormal pulsations or masses, normal active bowel sounds, and mild tenderness in the left lower quadrant. No rebound tenderness, guarding, or other signs of peritoneal irritation were found. Examination of the arms showed normal pulses on both sides. All pulses were absent in both legs. The patient showed no stigmata of chronic peripheral vascular disease. The patient then underwent noninvasive vascular studies. Her anlde-brachial indexes were 0.30 on the left side and 0.46 on the right. Pulse-volume recordings indicated severe obstructive arterial disease of the right and left legs. The pulsatile wave forms were markedly decreased throughout both legs and flat in the feet. These noninvasive studies were consistent with severe obstructive bilateral aortoiliac disease. The complete blood cell count and electrolyte and liver function tests wcre within normal limits; however, the patient had an elevated sedimentation rate of 129. Radiographic studies then were performed to confirm the physical 487

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Fig. 1. MRI shows lobulated mass in rctroperitoneum above aortic bifurcation (arrow).

Fig. 2. Abdominal aortogram shows total aortic occlusion.

findings. An MRI scan showed the presence of a lobulated mass (3 x 3.5 cm) in the retroperitoneum just above the aortic bifurcation (Fig. 1). The mass demonstrated low T1 signal intensity with areas of low as well as high T2 signal intensity. There was no communication with the aorta. No lymphadenopathy was noted, and the liver, spleen, pancreas, and lddneys were found to be normal in appearance. The low and high T2 signal intensity on the MRI scan suggested a histologically complex mass with areas of high fluid content and necrosis (high signal) and fibrosis (low signal).

The patient then underwent magnetic resonance angiography of the abdominal aorta, which showed occlusion of the distal abdominal aorta with no demonstrable flow. These findings were confirmed by an aortogram, which showed total occlusion of the abdominal aorta just below the renal arteries (Fig. 2). The celiac artery, both renal arteries, and the superior and inferior mesenteric arteries were patent. Extensive collateral flow was present with reconstitution of the common femoral arteries on both sides and patent superficial femoral arteries to the level of the knees. No evidence of tumor ncovascularity was noted on these studies. The remainder of the aorta was free of any atherosclerotic changes. The differential diagnosis at the time of this evaluation included: (1) aortitis (elevated sedimentation rate); (2) atypical retroperitoneal fibrosis; (3) lymphadenopathy from lymphoma or metastatic disease; and (4) primary aortic tumor. The patient was subsequently taken to the operating room for exploration. The intraoperative findings confirmed the radiographic findings. A large mass (4 × 2.5 × 2.5 cm) was indistinct from the left lateral wall of the aorta. The distal aorta and both iliac arteries were completely occluded. There was no involvement of the inferior vena cava or ureters. No liver lesions, tumor implants, or ascites were found. The aorta was clamped below the renal arteries, and the common iliac arteries were clamped; the aorta and both common iliac arteries were resected en bloc. A portion of the specimen was sent for frozen section, and the preliminary diagnosis of sarcoma, probably leiomyosarcoma, was made. An aortobifemoral grafting procedure was not performed at the time of surgery because the patient was going to receive high-dose radiation immediately after surgery, and we were concerned that the graft would be in the radiation field. We had no experience with anastomotic healing with this level of radiation treat-

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Fig. 3. Microscopicsectionoftumormassshowsitsorigininaorticwall(hematoxylinandeosin; original magnification x60).

Fig. 4, Microscopic section of tumor mass shows spindle cells in fascicular arrangement. Also noted are nuclear atypia and frequent mitotic figures (hematoxylin and eosin; original magnification x100). ment. During surgery, a member ofthc radiation oncology staff was consulted to visualize the tumor bed and mark the boundaries for radiation treatmcnt with surgical clips. The gross spccimen consisted ofa 6-cm segment of the

aorta and its bifurcation. A large, pale, tan, well-circumscribed mass appeared to arise from the outer wall of the aorta. This mass measured 4 x 2.5 x 2.3 cm. The lumen of the aorta was hemorrhagic, and central necrosis was present.

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T a b l e I. Clinical, p a t h o l o g i c , a n d r a d i o l o g i c features o f p r i m a r y aortic t u m o r s

Reference

Sex~age (years)

Browdowski 18731

M/52

Miura, 1891 n

M/38

Aufferman, 191212 Nencld, 1946 is

M/38 M/46

Karhoft; 195214

M/55

Kovaleva and Press, 1959 is Detrie, 196016; Kattus et al., 19602 Zeitlhofer et al., 196317

M/65 F/22

Symptoms and signs Weight loss, abdominal pain, parasthesiae of hands and feet Pathologic fracture of right femur; thoracic and sacral pain Abdominal pain, weight loss Abdominal pain suggesting appendicitis or cholecystitis Headache, abdominal pain, hypertension

Abdominal pain radiating into right leg, hypertension, osseous metastases Angiography: occlusion of left renal artery Hypertension, diminished femoral pulses

Kaigorodova and Berezovskaya, 1963 TM Sladden, 196419 Sladden, 196419

Dyspnea, tachycardia M/3 months Headache, weight loss, fever, absent pulses F/62 in fight arm M/64 Lumbago and sciatica, swelling of right leg M/59 Bilateral leg pain, absent pulses in fight leg

Smeloffet al., 19652°

F/65

Stevenson et al., 197121

M/60

Winkelman et al., 197122 M/65 Silverman and Wexler, 19722s F/62 Salm, 197224 Kimbrell and Kasa, 19732s Stefelaar et al., 197526

F/60

Crum et al., 197527 Hernandez et al., 1979 is

F/58 M/42

Weinberg and Maini, 19809

M/48

Mifili et al., 198129

M/64

Fehrenbacher et al., 19813°

M/67

Mason et al., 198231

M/70

Schmid et al., 198432

M/75

Hermanek et al., 198533

F/47

Wright et al., 1985 l° Becquermin et al., 1988 s4

F/46 M/67

Josen et al., 19893

M/75

Schipper et al., 19892

W/74

Higgins et al., 1991 ss

M/65

Weiss et al., 19916

M/63

Steinberg et at., 199336

M/48

Present case, 1994

F/51

F/58 M/70

Radiologic findings

m

Angiography: filling defect in lower aorta

Hypertension, dizziness, upper body edema Angiography: blockage of arch at left subclavian artery Low back pain, abdominal pain, hypertension Pain in both legs, cutaneous metastases Angiography: filling defect Headache, dizzy spells, hypertension Angiography: filling defect Backache, pathologic fracture of right hip Headache, chest pain, hypertension Angiography: filling defect, obstruction Claudication, diminished pulses in both above bifurcation legs Pleuritic pain Back pain, testicular pain, pulsatile abdomi- Angiography: aneurysm nal mass Angiography: extensive atherosclerosis, anHypertension, abdominal aneurysm eurysm, occlusion of several arteries Angiography: complete occlusion 3 cm disSevere pain and diminished pulses in both tal to renal arteries legs Angiography: filling defect, stenosis of right Pain and absent distal pulses in right leg superficial femoral artery Angiography: filling defect. CT: intralumiAbdominal pain, anorexia, weight loss nal tumor Angiography: filling defect, descending Symptoms of bilateral femoral arterial aorta femoral arterial occlusion occlusion Angiography: aneurysm, pathologic vessels. Back pain, abdominal pain CT: aneurysm, liver rnestastases. Ultrasound: same Symptoms of bowel infarction Claudication, metastatic cutaneous nodules, Angiography: occlusion at aortic bifurcation. CT: intraluminal mass decreased right leg pulses Angiography: filling defect. CT: intralumiAcute arterial occlusion of left leg, nal mass claudication Angiography: dilation of aorta. CT: mass in Back pain, acute chest pain contact with aorta. Angiography: intraluminal tumor. CT: mulAcute abdominal pain tiple filling defects. MR: increased signal mass in aora, filling defect Angiography: Dilation of graft. CT: thickAbdominal pain, back pain, sciatica ened aortic wall. MR: no ancurysm Acute substernal, epigastric, and back pain, CXR: ancurysm. Angiography: saecular aneurysm. CT: saccular aneurysm weight loss Claudication, absent lower extremity pulses Angiography: aortic occlusion. MR: periaortic mass. US: periaortic mass

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Site

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Size (cm)

Type

11 x 8

I

Fibrosarcoma

9

I

Spindle and giant cell sarcoma

4.5 3.5 x 3.5 x 2

M M

Spindle and giant cell sarcoma Fibrosarcoma

3,5 x 2.5

I

Primitive mesenchymal cell t u m o r

?

I

Fibrosarcoma

30

I

Fibromyxoma

6.5 x 2 x 0.5 i3

I I

Fibromyxosarcoma Fibrosarcoma

2.5 x 2.5 x 0.5 ?

I I

Intimal sarcoma Intimal sarcoma

20 x 1

I

Fihromyxosarcoma

4 x 2

I

Fibromyxosarcoma

Abdominal, level o f bifurcation

?

I

Angiosarcoma

Thoracic, arch extension in fight subclavian and left carotid artery Thoracic Abdominal and thoracic, arch to renal arteries Abdominal, level o f bifurcation

?

I

Myxoma

3.5 x 2 x 2 18 x 2 4

M I I

Fibrosarcoma Myxoma Undifferentiated malignant t u m o r

Thoracic, distal to left subclavian artery Abdominal

6 x4 x 4 12 x 7.5 x 5

M M

Fibroxanthosarcoma Leiomyosarcoma

Thoracic

7.5 x 1.5 x 2

M

Malignant fibrous hystiocytoma

Abdominal

4 x 5x 3

M

Leiomyosarcoma

Abdominal

6x 2

I

Angiosarcoma

Abdominal, coeliac axis to below renal arteries

5x 4

I

Angiosarcoma

8 x 4.5

I

Endothelioma

Abdominal

?

I

Histiocytoma

Abdominal

5x4

I

Intimal sarcoma

Abdominal

I

Angiosarcoma

Thoracic and abdominal

I

Histiocytoma

Thoracic Thoracic, 7 cm below left subclavian artery to 6 cm above celiac axis Abdominal, 1.5 cm above celiac axis to iliac arteries Abdominal Thoracic and abdominal, 4 cm below isthmus to belove renal arteries Abdominal, level o f renal arteries to 2 cm above bifurcation Thoracic and abdominal cast-like turnor Thoracic and abdominal, extension into celiac artery Thoracic, extension into fight subclavian artery Abdominal, 3 to 5 cm above bifurcation Abdominal at bifurcation, extension into both iliac arteries Thoracic and abdominal, extension into left subclavian and left renal artery Abdominal, level o f renal arteries

Thoracic

Thoracic

Histology

Leiomyosarcoma

Thoracic

I

Undifferentiated Sarcoma

Abdominal

Angiosarcoma

Thoracic

Leiomyosarcoma

Abdominal

4x2.5x2.3

I

Leiomyosarcoma

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Microscopically, the tumor originated in the aortic wall. The tumor consisted of spindle cells in a fascicular arrangement. Hypercellularity, nuclear atypia, and frequent mitotic figures were noted (Figs. 3 and 4). Results ofimmunoperoxidase stains were positive for desmin, muscle specific actin, and vimentin, confirming the smooth muscle origin of the tumor cells. The electron microscopic ultrastructural studies revealed pleomorphic tumor cells with smooth muscle differentiation. Thc final pathologic diagnosis was high-grade sarcoma displaying smooth muscle differentiation. The precise cell lineage is uncertain because the tumor was so poorly differentiated, but the presence of desmin and muscle-specific actin would suggest smooth muscle origin, making this a primary leiomyosarcoma of the abdominal aorta. After surgery, the patient did well and was discharged in good condition on the eighth day after surgery. The patient's postoperative metastatic workup included a computed tomographic (CT) scan of the chest and abdomen. The results of all of these studies were normal, with no evidence of metastasis or lymphadenopathy. This patient was treated with a primary surgical resection. After surgery, she received 63.6 Gy in 34 fractions, using 18 MeV photons in a shrinking field technique. Although the claudication initially improved, the patient returned 6 months later with pain that was localized to the left ilium and femur. A technetium bone scan and correlative CT scan indicated two large lytic lesions involving the sacrum and left femur, respectively. Because of a pending pathologic fracture, an urgent internal fixation with placement of an intramedullary rod was performed. On pathologic examination, the patient was found to have a highgrade leiomyosarcoma that was identical to her primary tumor. The patient then received 30 Gy in 10 fractions to the ilium and left femur. At this time, CT scans indicate multiple pulmonary metastases. The patient is currently ambulatory and has achieved palliative relief of her pain at 18 months from her original surgical resection.

DISCUSSION Primary tumors o f the aorta are rare. Since the initial report by Brodowsld in 1873,1. a search o f the literature has produced a series o f 36 cases: 33 malignant and three benign (Table I). Brodowski's case involved a 52-year-old man who had back pain, cachexia, and parcsthesias and was diagnosed with a thoracic fibrosarcoma at autopsy. This patient was also found to have metastases to peritoneum, spleen, liver, kidneys, and pancreas. Kattus et al.2 in 1960 are credited with the only other antemortem diagnosis o f a primary aortic t u m o r in addition to our present case. All other cases have been diagnosed only at the time o f p o s t m o r t e m examination.3 In the case reported by Kattus et al., the patient was a 22-year-old w o m a n in w h o m a t u m o r o f

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mesenchymal origin occluded the aorta just beyond the arch, producing physical signs o f coarctation o f the aorta. The t u m o r also extended into the renal arteries, resulting in malignant hypertension o f the Goldblatt kidney type. 4 Vascular lciomyosarcomas, although rare, usually arise in the inferior vena cava or other large vcins. 2 These locations are five times more frequent than in arteries. The pulmonary artery is affected twice as often as other systemic arteries. Kcvorldan and Ccntros 5 tabulated the occurrence o f vascular leiomyosarcomas over morc than a century and found the sites o f occurrcncc, in order o f decreasing frequency, to be: (1) the inferior vena cava; (2) other large veins; (3) pulmonary artery; and (4) large systemic arteries. In a report by Weiss et al., four cases ofangiosarcoma were described at the site of a Dacron vascular prosthesis, suggesting a possible association between Dacron graft material and malignant aortic tumors .6-8 Oppenheimer et al. 7 demonstrated in animal studies that plastic films including Dacron embedded subcutaneously in the abdominal wall o f murine species would result in sarcoma. The latency period was found to vary from 7 months to 21/2 years, with most tumors occurring 1 to 2 years after implantation. It also was found that the physical form o f the plastic influenced carcinogenicity. Films without pores were more carcinogenic than films with pores, and an invcrse relationship between pore size and the develo p m e n t of t u m o r was noted. H u m a n studies to date have failcd to demonstrate this association. 9 Wright et al.10 have classified these tumors according to their site o f origin within the aortic wall: T u m o r s p r i m a r i l y involving the intima. These tumors grow into the aortic lumen, extending along the intima or growing as polypoid masses. The clinical presentation is caused by the level o f obstruction o f the lumen. For example, there could be severe hypertension if the renal arteries are involved; gastrointestinal ischemia if the celiac, superior, or inferior mesenteric arteries are involved; or decreased peripheral pulses if the c o m m o n iliac arteries or their branches are involved. T h r o m b o e m b o l i c metastases may occur with intimal tumors. These metastases can mimic athcrosclerosis and may bc overlooked at surgery. T u m o r s arising in the m e d i a o r adventitia. This type of t u m o r forms mass lesions with intramural or extramural extension. These lesions may have more vague signs: back or abdominal pain, systemic symptoms o f fever or anorexia, or as aneurysmns. These lesions only produce vascular symptoms if there is compression or invasion o f the lumen or secondary

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thrombosis o f the aorta. The case presented here is o f the second type. The tumor arose from the aortic wall, and the obstructive arterial symptoms resulted from compression o f the aortic lumen and subsequent thrombosis. Histologically, this tumor was o f muscle origin. The radiologic appearance of aortic tumors may suggest their site o f origin. Tumors o f the intima may appear as filling defects and obstructions on arteriography, as well as intraluminal masses on CT scan or MRI. The mural type o f aortic tumor may appear like an aneurysm or obstruction on arteriogram, as a periaortic mass, or as an aneurysm on CT scan or MRI. Because these tumors are usually noticed late when a cure is n o t possible, management is based on presenting symptoms. En bloc resection and adjuvant radiation therapy can be administered for local pain control and to try to reduce local recurrence o f the tumor. Local regional control for soft tissue tumors is best achieved by surgical resection followed by radiation therapy. At this time, no available data supports the use o f adjuvant chemotherapy, is The mean survival time o f patients with vascular sarcoma is between a few months and 3 years, with an average o f 1.5 years. 14 REFERENCES

1. Brodowski W. Primares Sarkom der Aorta Thoracica mit Verbreitung des Neugeebildes in der unteren Korperhalfte. Jahnesbuch Leistungen Gesellschaft Medizin 1873;8:243-6. 2. Kattus A, Longmire W, Cannon J, Webb R, Johnston C. Primary intraluminal tumor of aorta producing malignant hypertension. N Engl J Med 1960;262:694-700. 3. Schipper J, van Oostayen J, den Hollander J, van Seyen A. Aortic tumours: report of a case and review of the literature. Br J Radiol 1989;62:35-40. 4. Iosen A, Khine M. Primary malignant tumors of the aorta. J Vasc Surg 1989;9:493-8. 5. Kevorkian J, Cento DP. Leiomyosarcoma of large arteries and veins. Surgery 1973;73:390-400. 6. Weiss WM' Riles TS' G°uge T H ' Mizrachi HH" Angi°sarc°ma at the site of a Dacron vascular prosthesis: a case report and literature review. J Vasc Surg 1991;14:87-91. 7. Oppenheimer B, Oppenheimer E, Stout A. Sarcomas induced in rats by implanting cellophane. Proc Soc Exp Biol Med 1948;,67:33-4. 8. Fehrenbacher J' B°wers W' Strate R' Pittman J' Angi°sarc°ma of the aorta associated with a Dacron graft. Ann Thorac Surg 1981;32:297-301. 9. Weinberg D, Maini B. Primary sarcoma of aorta associated with a vascular prosthesis. Cancer 1980;46:398-402. 10. Wright E, GlickA, Virmani R, Page D. Aortic intimaI sarcoma with embolic metastases. Am J Surg Pathol 1985;9:890-7. 11. Miura M. Das primare Risenzellen sarcom der Aorta Thoracica. Internationale Beitrage Wisserchaftliche Medizinische Fortschrilte RudolfVirchow, 1891;2:249-55.

Malone et al.

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12. Aufferman H. Primare Aortengeschwulst mit eigentumlichen Risenzellen. Zeitschrift far Krebsforschung 1912;lh294301. 13. Nencki L. Zur Kenntuis der Primartumoren der grossen Ge£assamme. Ueber einen fall von primaren Sarcom der Aorta abdominalis. Cardioiogia (Basel) 1946;10:1-24. 14. Karhoff B. Primartumor der Aorta. Zentralblatt far Allgemeine Pathologie und Pathologische Anatomie. 1952;89:46. 15. Kovaleva AN, Press BO. A case of primary sarcoma of the intima of the aorta. Arkh Patol 1959;21:62-5. 16. Detrie R Tumeur primitive intravasculaire de l'aorte. J Chir (Paris) 1960;80:666-8. 17. Zeitlhofer J, Holzner JH, Krepler P. Primates Fibrmyosarkom der Aorta. Krebsarzt 1963;18:259-69. 18. Kaigorodova P, Berezovskaya E. Endothelioma of the thoracic aorta. Grudnaya Khirurgiya 1963;4:88-90. 19. Sladden R~ Neoplasia of the aortic intima. I Clin Pathol

1964;17:602-7. 20. SmeloffE, Reece J, Masters J. Primary intraluminal malignant tumor of the aorta. Am J Cardiol 1965;15:107-10. 21. Stevenson 1, Burkhead H, Trueheart R, McLaren J. Primary malignant tumor of the aorta. Am J Med 1971;5h553-9. 22. Winkelmann R, van Heerden J, Bernatz P. Malignant vascular endothelial tumor with distal embolization. Am J Med 1971; 51:692-4. 23. Silverman J, Wexler L. Primary intraluminal tumor of the aorta: case report with preoperative angiographic diagnosis. Radiology 1972;102:581-2. 24. Salm R. Primary fibrosarcoma of the aorta. Cancer 1972;29: 73-83. 25. Kimbrell O, Kaasa L. Primary intraluminal aortic myxoma with involvement of several vertebrae. JAMA 1973;226:459-60. 26. Stefelaar JW, Van der Heul RO, Blackstone E, Vos A. Primary sarcoma of the aorta. Arch Pathol Lab Med 1975;99:139-42. 27. Crum C, Feldman P, Nolan S. Primary fibroxanthosarcoma of the thoracic aorta. Virchows Arch 1978;379:351-8. 28. Hernandez F, Stanley T, Raganath K, Rubinstein A. Primary leiomyosarcoma of the aorta. Am J Surg Patho11979;3:251-6. 29. Milili J, La FlareA, Nemir P. Leiomyosarcoma ofthe abdominal aorta: a case report. Surgery 1981;89:631-4. 30. Fehrenbacher J, Bowers W, Strate R, Pittman J. Angiosarcoma of the aorta associated with a Dacron graft. Ann Thorac Surg 1981;32:297-301. 31. Mason M, Wheeler J, Gregory R. Primary tumours of the aorta: report of a case and review of the literature. Oncology 1982;39:167-72. 32. Schmid E, Port S, Carroll R, Friedman N. Primary metastasizing aortic endothelioma. Cancer 1984;54:1407-11. 33. Hermanek P, Gentsch H, Scheele J. Maligne Tumoren der grossen Gefasse. Zwei Fall Berichte Chirurg 1985;56:I20-2. 34. Bequermin J, Lebbe C, Saada F, Avril M. Sarcoma of the aorta: report of a case and a review of the literature. Ann Vasc Surg 1988;2:225-30. 35. Higgins R, Posner M, Moosa H, Staley C, Pataki K. Mesenteric infarction secondary to tumor emboli from primary aortic sarcoma. Cancer 1991;68:1622-7. 36. Steinberg J, Johnson E, Benda J, Lanza L. Primary leiomyosarcoma of the thoracic aorta presenting as a contained rupture. Ann Thorac Surg 1993;56:1387-9.

Submitted Sep. 8, 1995; Jan. 17, 1996.