Pulmonary Artery Obstruction due to Malignant Fibrous Histiocytoma

present case appears to be unique in the sense that twodimensional echocardiography permitted direct dynamic visualization of small emboli moving freely in the right-sided chambers, toward the pulmonary artery. Clinical and postmortem evidence was thereafter obtained to corroborate the diagnosis raised by echocardiography. We ruled out a hypothesis of microcavitations created by intravenous therapy because the infusion was very slow to produce images with the intensity observed in this case. We have recently infused peripherally normal subjects as well as patients with overt heart failure, at rates of up to 3 ml/min, without seeing any images like those documented in this case. Only when the infusion was done through catheters placed in the superior vena cava have we been able to detect microcavitations during slower infusion rates. In the same way, the echodense images visualized in this case appear to be more intense than the microbubbles observed in tricuspid regurgitation. Although it is difficult to ascertain the diagnostic value of two-dimensional echocardiography, in the clinical context of suspected thromboembolism, we believe that the specificity and sensitivity of such noninvasive methods should be measured by further studies. It is possible that the finding of mobile emboli in the right cardiac chambers can be useful for immediate assessment of the need of emergency surgery for embolectomy or interruption of the inferior vena cava, in selected critically ill patients, thus avoiding the risks of invasive approaches such as angiography.

REFERENCES 1 Covarrubias EA, Sheik MU, Fox LM . Echocardiography and pulmonary embolism. Ann Intern Med 1977; 87:720 2 Kasper W, 'Ii-eese N, Bechtold H, Pop T, Meinertz T. Diagnosis of acute pulmonary embolism and thrombosis by echocardiography.

Lancet 1981; 2:202 3 Lim SP, Hakim SZ, van der Bel-Kahn JM. Two-dimensional echocardiography for detection of primary right atrial thrombus in pulmonary embolism. Am Heart J 1984; 108:1546 4 Manno BV, Panidis IP, Kotler MN, Mintz GS, Ross J. Twodimensional echocardiographic detection of right atrial thrombi. Am J Cardiol 1983; 51:615 5 Quinn TJ, Plehn JF, Liebson PR. Echocardiographic diagnosis of mobile right atrial thrombus: early recognition and treatment. Am Heart J 1984; 108:1548

6 Rosenzweig MS, Nanda NC. 'IWo-dimensional echocardiographic detection of circulating right atrial thrombi. Am Heart J 1982; 103:435 7 Starkey IR, de Bono DP. Echocardiographic identification of right

cardiac intracavitary thromboembolus in massive pulmonary embolism. Circulation 1982; 66:1322

Pulmonary Artery Obstruction due to Malignant Fibrous Histiocytoma* Brian W. Carlin, M.D.;t and Kenneth M. Ma&er, M.D ., F.C.C.P.

Obstruction of the pulmonary artery can be due to a variety of conditions, including chronic thromboembolic disease, neoplasia, and 8brosing mediastinitis. Differentiation can be difficult. We report a ease of malignant 8brous histiocytoma causing intravascular obstruction and include a review of the literature.

T

he differential diagnosis of chronic thromboemlx>'ic obstruction of major pulmonary arteries includes ro.;-e instances of neoplasms originating in these arteries. u Most such tumors are diagnosed post mortem. 3 We report herein the findings in a patient who presented with total obstruction of the left main pulmonary artery, in whom the diagnosis was made ante mortem and in whom resection was performed. CASE REPORT

A 68-yelll'-Old man was well until September 1985, when dyspnea on exertion developed. In October a paroxysmal nonproductive cough and daily evening temperature elevations appeared. Symptoms briefly resolved with antibiotic therapy and then recurred. A chest x-ray film in December 1985 demonstrated fullness in the aortopulmonary window and left hemidiaphragmatic elevation. Pulmonary function tests revealed the following: forced expiratory volume in one second (FEVJ, 1.51 L (43 percent of predicted); forced vital capacity, 3.01 L (60 percent of predicted); and carbon monoxide diffusing capacity (Dsb), 14.6 ml/min/mm Hg (46 percent of predicted). Bronchoscopic findings were unremarlcable; brushings and washings revealed only atypical cells. A computerized tomogram of the chest suggested a filling defect in the left main pulmonary artery. A gallium scan showed abnormal uptalce in the left perihilar region. A perfusion scan (Fig I) showed no perfusion to the left lung and several subsegmental defects in the right lung. A digital-subtraction pulmonary angiogram showed complete occlusion of the left main pulmonary artery, with a normal right main pulmonary artery. An echOOu-diogram was normal. When the patient was referred to our institution in early January, his symptoms included shortness of breath, a nonproductive cough, and an 11.3-kg (25-lb) loss ofweight since September. He was afebrile on admission and remained so. The findings from physical examination were unremarkable. The patient was mildly anemic (hematocrit reading, 32 percent). A chest x-ray film and perfusion scans were unchanged. Arterial blood gas analysis disclosed the following values: pH, 7.45; arterial oxygen pressure, 62 mm Hg; and arterial carbon dioxide tension, 41 mm Hg. An electrocardiogram showed left anterior fascicular block. Pulmonary function tests showed the following: FEV" 1.66 Usee (50 percent of predicted); ratio of residual volume over total lung capacity, 57 percent; and Dsb, 11.9 ml/minlmm Hg (49 percent of predicted). Oxygen saturation did not decline with exercise at 2 mph for six minutes. The results of impedance plethysmography of the legs were normal. Cardiac catheterization disclosed pulmonary arterial pressure of 34120 mm Hg (mean 26 mm Hg), a pulmonary arterial wedge pressure ofl8 mm

sided

8 van Kuryk M, Mols P, Englert M. Right atrial thrombus leading to pulmonary embolism. Br Heart J 1984; 51:462

*From the Department of Pulmonary and Critical Care Medicine, University of CalifOrnia School of Medicine, San Diego. tFellow of the American Lung Association of CalifOrnia. Reprint~: Dr. Carlin, 225 DtckWon Snwt, San DWgo 92103 CHEST I 82 I 1 I JULY, 1987

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FIGURE 1. Perfusion scan (anterior view) showing no perfusion to left lung and several subsegmental defects in right lung. Hg, and a cardiac index of 3.0 Umin/sq m. Bilateral pulmonary angiography (Fig 2) revealed total obstruction of the left pulmonary artery shortly beyond its origin; there was no evidence of thromboembolic disease of the right pulmonary artery or its branches. C~ronary angiography revealed a 90 percent stenosis of the right coronary artery. Fluoroscopic examination demonstrated normal diaphragmatic

FIGURE 2. Angiogram of left pulmonary artery showing total obstruction distal to bifurcation.

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movement. Chest and abdominal computerized tomographic scans disclosed no evidence of metastatic disease. A left mediastinotomy was negative. We elected to explore the patient's pulmonary arteries through a median sternotomy. On opening the left main pulmonary artery, we encountered thrombotic material obstructing it; however, as dissection was extended, whitish quite friable material was encountered which extended into the left upper lobe artery and its segmental branches. The left descending pulmonary artery was occluded with what appeared to be organized thrombus. The right main pulmonary artery and its lobar and segmental branches were normal. Asaphenous venous bypass of the right coronary artery was performed. Pathologic examination of the material removed disclosed proximal organized thrombus distal to which was a highly pleomorphic spindled neoplasm with frequent atypical mitoses and scattered multinucleate cells. The diagnosis of intravascular malignant fibrous histiocytoma was made. There was no evidence of invasion into the left pulmonary arterial wall, a small portion ofwhich Oust beyond the origin of the occlusion) was biopsied. The material removed from the left descending pulmonary artery was organized thrombus. Some weeks later, after a further detailed evaluation fur metastatic disease was negative, the patient underwent a left pneumonectomy. Pathologic examination of the lung removed revealed an intravascular tumor in the left upper lobe segmental branches, with a single area of invasion through a segmental pulmonary artery into the pulmonary parenchyma. Mediastinal lymph nodes were, as at the first operation, normal. Ten months after surgery, the patient was doing well, without evidence of recurrence. DISCUSSION

This patient presented with many of the historical, physical, and laboratory features associated with chronic thrombotic obstruction of major pulmonary arteries;• however, he was round to have a unique cause of pulmonary artery obstruction, an intravascular malignant fibrous histiocytoma. Organized thrombus had developed proximal (left main pulmonary artery) and distal (left descending pulmonary artery) to the tumor. Shortness of breath, progressive dyspnea on exertion, a nonproductive cough, and the lack of a clear-cut history of venous thromboembolism are presentations common to both thromboembolic and neoplastic obstruction of the pulmonary artery;1 however, our patients history of loss of weight and fever was atypical fur patients with chronic thromboembolism. Roentgenographically, decreased pulmonary vascular markings or volume loss can be seen in both diseases, but the presence of a hilar mass, infiltrate, or parenchymal nodules suggests tumor involvement. 5 Filling defects on the perfusion scan are universally present in both states. Many patients with neoplastic obstruction of the pulmonary artery are treated fur venous thromboembolism, e. 7 and the diagnosis of a pulmonary artery tumor is rarely considered ante mortem. At surgery the two diseases can resemble each other, 8 and only histologic examination can provide the diagnosis. In many cases, as in ours, thrombus fOrmation occurs in concert with the tumor itself. Malignant fibrous histiocytoma was initially characterized by O'Brien and Stoufl as a group of tumors with a common origin from tissue histiocytes. The diagnosis has achieved greater frequency in recent years, and many cases previously diagnosed as pleomorphic rhabdomyosarcoma or undifferentiated fibrosarcoma are now classified as malignant fibrous Pulmonary Artery Obetructlon (Carlin, Moser)

Table 1-CUnicoptJthologic Obaerootiona in 20 lbtienU with MaligntJnt Fibroua Hiftiocrltomo if the Lung

Reference Kern et al

11

Bedrossian et al 13 Chowdhury et al 14 Misra et al 10 Sajjad et al 16 Mills et al 17 Lee et al 11

Year 1977 1979 1980 1981 1981 1982 1984

Ros et al 1~

1984

Case repo~ Venn et al11

1985 1986

Patient, Sex, Age (yr) 1, M, 53 2, F, 25 3, M, 51 4, F, 52 5, M, 45 6, F, 65 7, F, 60 8, M, 62 9, M, 54 10, M, 69 11, F, 62 12, M, 67 13, 14, 15, F, 46 16, F, 32 17, M, 62 18, M, 33 19, M, 62 20, F, 61

Duration of Life Surgery

Radiation Therapy

+ +* +t +t +*§ + + + + + +

+* + + + + +

Chemotherapy

+

Metastases

Alive

Cerebral Cerebral

5mo

Liver Cerebral; renal Cerebral Sternum

3 mo

Dead lOmo 14 mo 5 mo 5 mo

18 mo 12 mo

Liver; pericardium

+

6mo 8 mo 120 mo 60 mofl

6mo 18 mo 60mo

+ Atrium Intraoral

11 mo 2mo 15 mo

*Involvement of pulmonary artery found. tPatient had bilateral nodules, one of which was resected. tResection not performed; only biopsy of pulmonary mass. §Thmor first found at embolectomy; subsequent surgery revealed extent. IIPatient died of congestive heart failure without evidence of tumor recurrence. ,Neither characteristics of patients nor therapy discussed in article. 7 Myerson PJ, Myerson DA, Katz R, Lawson JP. Gallium imaging histiocytoma. This tumor is believed to be the most common in pulmonary artery sarcoma mimicking pulmonary embolism: soft tissue sarcoma of adult life. While primarily found in the case report. J Nucl Med 1976; 17:893-95 extremities, abdominal cavity, and retroperitoneal re8 Shoenfeld Y, Avidor I, Liban E, Levy MJ, Pinkhaus J. Primary gion, 10.u 20 cases of malignant fibrous histiocytoma involving leiomyosarcoma of the pulmonary artery. Respiration 1981; the pulmonary parenchyma primarily have been described 41:208-13 9 O'Brien JE, Stout AP. Malignant fibrous xanthomas. Cancer (Table 111-11). In 15 cases, surgical resection was performed. 1964; 17:1445-55 Survival ranged from three months to ten years, with two 10 Weiss SW, Enzinger FM. Malignant fibrous histiocytoma: an long-term survivors (five years and ten years) in the group analysis of 200 cases. Cancer 1978; 41:2250-66 with resection. In no prior case did the tumor appear to arise 11 Kearney MM, Soule EH, Ivins JC. Malignant fibrous hiswithin the pulmonary artery. tiocytoma: a retrospective study of 167 cases. Cancer 1980; 45:This case illustrates several points. First, pulmonary 167-78 artery tumors can mimic many of the signs, symptoms, and 12 Kern WH, Hughes RK, Meyer BW, Harley DP. Malignant findings associated with chronic thrombotic obstruction of fibrous histiocytoma of the lung. Cancer 1979; 44:1793-801 the pulmonary artery. Secondly, a high index of suspicion can 13 Bedrossian CWM, Verani R, Unger KM, Salman J. Pulmonary lead to early surgery and, hopefully, an improved outcome. malignant fibrous histiocytoma. Chest 1979; 75:186-89 14 Chowdhury LN, Swerdlow MA, Jao W, Kathpalia S, Desser RK; ACKNOWLEDGMENT: We thank Dr. Ben Bridges of the UniverPostirradiation malignant fibrous histiocytoma of the lung. Am J sity of Texas Tyler Medical Center for his kindness in providing Clin Patholl980; 74:820-26 follow-up data about this patient. 15 Misra DP, Sunderrajan EV, Rosenholtz MJ, Hurst DJ. Malignant REFERENCES fibrous histiocytoma in the lung masquerading as recurrent pulmonary thromboembolism. Cancer 1983; 51:538-41 1 Bleisch VR, Kraus FT. Polypoid sarcoma of the pulmonary trunk. 16 Sajjad SM, Begin LR, Dail DH, Lukeman JM . Fibrous hisCancer 1980; 46:314-24 tiocytoma of the lung: a clinicopathological study of two cases. 2 Shmookler BM, Marsh HB, Roberts WC. Primary sarcoma of Histopatholl981; 5:325-34 . the pulmonary trunk and/or right or left main pulmonary artery: 17 Mills SA, Breyer RH, Johnston FR, Hudspeth AS, Marshall RB, a rare cause of obstruction to right ventricular outflow. Am J Med Choplin RH, et al. Malignant fibrous histiocytoma of the medi1977; 63:263-72 astinum and lung. J Thorac Cardiovasc Surg 1982; 84:367-72 3 Baker PB, Goodwin RA. Pulmonary artery sarcomas. Arch 18 Lee .J1: Shelburne KD, Linder J. Primary malignant fibrous Pathol Lab Med 1985; 109:35-9 histiocytoma of the lung. Cancer 1984; 53:1124-30 4 Moser KM, Spragg RG, Utley J, Daily PO. Chronic thrombotic 19 Ros PR, Viamonte M, Rywlin AM. Malignant fibrous hisobstruction of major pulmonary arteries. Ann Intern Med 1983; tiocytoma. Am J Roentgenoll984; 142:753-59 99:299-305. 20 Case records of the Massachusetts General Hospital (case 5 Moffitt RE, Chang CH, Slaven JE. Roentgen consideration in primary pulmonary artery sarcoma. Radiology 1972; 104:283-88 19-1985). N Eng! J Med 1985; 312:1242-52 6 Olsson HE, Spitzer RM, Erston WF. Primary and secondary 21 Venn GE, Gellister J, DaCosta PE, Goldstraw P. Malignant pulmonary artery neoplasia mimicking acute pulmonary embofibrous histiocytoma in thoracic surgical practice. J Thorac Cardiovasc Surg 1986; 91:234-37 lism. Radiology 1976; 118:49-53 CHEST I 92 I 1 I JULY, 1987

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