Ann Thorac Surg 2005;80:1502-1504
© 2005 The Society of Thoracic Surgeons
Case report
Primary Lymphoma of the Aorta Presenting as a Descending Thoracic Aortic Aneurysm
Anthony L. Estrera, MD,
Eyal E. Porat, MD,
Rashad Aboul-Nasr, MD,
Ken Y. Sin, MD,
L. Maximilian Buja, MD,
Hazim J. Safi, MD
*
Department of Cardiothoracic and Vascular Surgery, The University of Texas at Houston Medical School, Memorial Hermann Hospital, Houston, Texas
Accepted for publication March 30, 2004.
* Address reprint requests to Dr Safi, Department of Cardiothoracic and Vascular Surgery, 6410 Fannin, Ste 450, Houston, TX77030 (Email: hazim.j.safi{at}uth.tmc.edu).
 |
Abstract
|
|---|
We describe a case of primary lymphoma of the thoracic aorta that presented as an aneurysm of the descending thoracic aorta. The aortic tumor was successfully resected with 2-year disease-free survival.
|
Introduction
|
|---|
Primary tumors of the aorta remain rare. Since the first primary aortic malignancy was reported in 1873 by Brodowski [1], fewer than 100 cases have been reported [2]. The majority of cases have been subtypes of sarcoma with some reports of angiosarcoma, malignant fibrous histiocytoma, and myxoma [2, 3]. Lymphomas associated with the aorta have been noted primarily to involve the abdominal aorta as either lymphoma associated with an abdominal aortic aneurysm [4], lymphoma eroding into the vasculature [5], or perivascular lymphoma leading to a vascular complication [6]. We describe a case of primary lymphoma of the thoracic aorta that presented as an aneurysm of the descending thoracic aorta.
A 63-year-old nonhypertensive woman presented for evaluation of a widened mediastinum on routine chest roentgenogram. She denied chest or back pain, fever, night sweats, or constitutional symptoms. Computed tomography of the chest revealed a descending thoracic aortic aneurysm with no mediastinal lymphadenopathy or pulmonary nodules (Fig 1). Preoperative evaluation that included pulmonary function tests and a cardiac evaluation were completed and noted to be normal. The patient underwent exploration through a modified left thoracoabdominal incision. The spinal cord protective adjuncts of distal aortic perfusion and cerebrospinal fluid drainage were used. Exploration of the left thorax revealed no obviously enlarged mediastinal lymphadenopathy or pulmonary nodules. However, the appearance of the lower descending thoracic aorta was abnormal. This segment of the aorta was thickened with a marked fibrous capsule surrounding the aorta. Distal aortic perfusion was begun and the descending thoracic aorta was cross clamped distally at the 12th intercostal level and proximally at the fourth intercostal level. The aorta was opened longitudinally and examined. Inspection of the aortic wall revealed a thickened fibrous wall with only mild atheromatous disease. No significant thrombus was noted. A portion of the aortic wall was excised and sent for preliminary frozen pathology, which revealed a poorly differentiated tumor. The entire descending thoracic aorta from T6 to T12 was completely excised en bloc including the periaortic tissue and pleura. The repair was completed in an end-to-end fashion using a 24-mm woven polyester tube graft. The intercostal arteries in this segment of the aorta were not patent and therefore were not reattached.
View larger version (124K):
[in this window]
[in a new window]
|
Fig 1. Chest computed tomographic scan revealing the enlarged segment of the descending thoracic aorta.
|
|
The specimen received in surgical pathology consisted of an aortic segment encased by a fleshy mass that was tightly adherent to the adventitial surface (Fig 2). The intimal surface of the opened aortic segment exhibited mild arteriosclerosis. Histologically the mass had features of a cellular neoplasm that completely replaced the adventitia of the aorta and adjacent soft tissue. The aortic media and intima were generally spared, although focal small infiltrates of neoplastic cells were identified within the aortic wall. The neoplasm had features of a lymphoid proliferation that had a predominantly diffuse pattern but showed focal nodular areas. The nodular areas were interpreted as neoplastic follicles. The follicles were composed predominantly of follicular small cleaved cells; however, there was a mixture of small cleaved and larger lymphoid cells in the diffuse areas. Histologically the neoplasm was classified as a grade II follicular lymphoma.
View larger version (142K):
[in this window]
[in a new window]
|
Fig 2. Excised segment of the descending thoracic aorta that was sectioned. The intimal surface of the opened aortic segment exhibits only mild arteriosclerosis. The majority of the aortic wall thickness is represented by the large fleshy mass that is adherent to the adventitial surface of the aorta.
|
|
Immunophenotyping was performed using flow cytometry and showed strong kappa light chain restriction on lymphoid cells that coexpressed the B cell marker, CD10, and were negative for the T cell marker, CD5. Immunohistochemical results correlated with the flow cytometric findings. By immunohistochemistry, many of the cells in the mass expressed the B cell marker, CD20, and were negative for the T cell marker, CD5; several cells in the neoplastic follicles expressed BCL-2. The negative staining for CD5 together with the focal positive staining of cells with BCL-2 in the neoplastic follicles were consistent with a B-cell lymphoma of follicle center cell derivation.
The patient's postoperative course was complicated by atrial fibrillation, requiring chemical conversion and anticoagulation. Further evaluation, including a bone marrow biopsy and computed tomographic scan of the abdomen and pelvis, showed no evidence of metastatic disease. No further treatment was administered. She was discharged in good condition on postoperative day 14. Follow-up evaluation at 30 months revealed no evidence of recurrent disease.
|
Comment
|
|---|
Non-Hodgkin's lymphoma is the sixth most common cause of death in the United States, but is nearly unknown in association with aortic disease [7]. Non-Hodgkin's lymphomas can start in lymph nodes, in a specialized lymphatic organ such as the spleen, or in lymph tissue found in organs such as the stomach or the intestines. However, because lymphocytes can circulate through the lymphatic vessels and bloodstream, abnormal lymphocytes can reach any part of the body and are prone to spread throughout. Low-grade lymphomas (diffuse, small lymphocytic; follicular, small cleaved cell; follicular mixed, small and large cell) such as those found in our patient, occur in 38% of all lymphoma patients [7]. Non-Hodgkin's lymphoma typically affects middle-aged and older adults. Non-Hodgkin's lymphoma in our patient was localized and she was without symptoms. Local disease is apparent in some patients, but most have multiple areas of involvement [7]. Weight loss, fever, night sweats, and asthenia typically characterize disseminated disease [7].
The incidence of lymphoma is believed to be on the rise. It has been associated with the Epstein-Barr virus and immune deficiency [8]. One of the few reported cases of malignant lymphoma infiltrating the abdominal aorta was a T-cell lymphoma with evidence of the Epstein-Barr virus in atypical T-lymphoid cells [6]. In diagnoses, non-Hodgkin's lymphoma must be differentiated from Hodgkin's disease, acute and chronic leukemia, metastatic carcinoma, infectious mononucleosis, tuberculosis, and other causes of lymphadenopathy, including pseudo lymphoma caused by phenytoin [8].
Computed tomography, magnetic resonance imaging, and transesophageal echocardiography may alert the physician to the possibility of non-Hodgkin's lymphoma, but a definitive diagnosis can only be made by histologic study of excised tissue. The radiographic findings in this case were initially considered to be thoracic aortic aneurysm. The computed tomographic features as seen in Figure 1 can be associated with either intramural hematoma or organized thrombus in an aneurysm. A differentiating feature that should be considered in cases of primary vascular malignancies is the symmetric circumferential thickening involving a localized segment of aorta. Commonly, organized thrombus or hematoma is associated with an asymmetric radiographic appearance of the aortic wall.
Tumors that masquerade as aneurysms usually go undiagnosed until surgical resection. At exploration abnormal appearance of aortic tissue may lead to a suspicion of an aortic malignancy. Frozen section pathologic evaluation should be performed to confirm a malignancy. If this evaluation reveals a malignancy that may be treated by adjuvant chemotherapy alone (eg, lymphoma), we still recommend complete excision, because a theoretical concern for an aortic wall rupture remains after the administration of chemotherapy, due to tumor necrosis. In addition, a definitive diagnosis often can not be made at frozen section evaluation.
In the case that a primary malignancy is suspected before surgical intervention, a radiographic guided tissue biopsy may be considered. Although fine needle aspiration may identify a specific malignancy like lymphoma, definitive diagnosis often still requires open biopsy and excision. Although the standard treatment for hematological malignancies remains to be chemotherapy, the treatment strategy for primary vascular malignancies is still unknown.
Although most primary tumors of the aorta are associated with poor long-term survival, resection with graft replacement can provide adequate treatment for localized aortic tumors as reported in this case.
|
References
|
|---|
- Brodowski W. Primäres Sarkom der. Aorta thoracica mit Verbreitung des Neugebildes in der unteren Köperhälfte [in German] Jahresb Leistung Fortschr ges Med 1873;8:243-246.
- Seelig MH, Oldenburg WA. Regarding primary aortic intimal sarcoma of the endothelial cell type with long-term survival J Vasc Surg 1998;28(4):756.[Medline]
- Greenberg SC, Khaja S, Klonaris CN, Weibaecher D, Safi HJ. Surgery for chondrosarcoma of the descending thoracic aorta Contemp Surg 2000;12(56):716-722.
- Kreel L, Bydder G. Associated lymphoma, and abdominal aortic aneurysm demonstrated by computed tomography J Comput Tomogr 1980;4(3):209-214.[Medline]
- Williamson AE, et al. Endovascular repair of a ruptured abdominal aortic and iliac artery aneurysm with an acute iliocaval fistula secondary to lymphoma Ann Vasc Surg 2002;16(2):145-149.[Medline]
- Kazerooni EA, Williams DM, Deeb GM. Thoracic periaortic lymphoma mimicking aortic dissection AJR Am J Roentgenol 1992;159(4):705-707.[Free Full Text]
- National Cancer Institute (U.S.) What you need to know about non-Hodgkin's lymphoma. 33. Bethesda, MD: U.S. Department of Health and Human Services Public Health Service National Institutes of Health; 1999Rev Aug ed. DHEW (NIH) Publication No. 99-1567.
- Knowles DM. Etiology and pathogenesis of AIDS-related non-Hodgkin's lymphoma Hematol Oncol Clin North Am 2003;17(3):785-820.[Medline]
Top
Abstract
Introduction
