ClinicalRadiology(1990) 41, 92-94
Primary Pulmonary Artery Sarcoma A Report of Two Cases, with Special Emphasis on the Diagnostic Problems P. D . B R I T T O N
Department of Radiology, Papworth Hospital, Cambridge Two cases of primary sarcoma of the pulmonary artery are presented. The variable clinical and radiographic features of this rare tumour are described with particular emphasis on its ability to mimic pulmonary thrombo-embolic disease.
P r i m a r y p u l m o n a r y a r t e r y s a r c o m a is a n u n c o m m o n t u m o u r a n d s i n c e its first d e s c r i p t i o n b y M a n d e l s t a m m (1923) o n l y 105 c a s e s h a v e b e e n r e p o r t e d i n t h e l i t e r a t u r e . Although histologically the tumours are very variable, w i t h o v e r 25 d i f f e r e n t t y p e s d e s c r i b e d , g r o s s a p p e a r a n c e s and behaviour are remarkably similar. The tumour almost invariably arises in the main pulmonary artery and spreads peripherally; retrograde spread involving the p u l m o n a r y v a l v e a n d r i g h t v e n t r i c l e is less c o m m o n . T u m o u r is u s u a l l y c o n f i n e d t o t h e t h o r a x a l t h o u g h d i s t a n t spread to the brain and abdomen has been reported. P r e s e n t a t i o n is u s u a l l y d u e t o o c c l u s i o n o f t h e p u l m o n a r y vasculature and right ventricular outflow obstruction.
Fig. 1-Case 1. Anterior view of perfusion lung scintigram showing marked reduction in perfusion throughout the left lung and further perfusion defects in the right lower lobel
CASE REPORTS
Case 1. A 34-year-old female presented with acute haemoptysis and a recent history of shortness of breath. The chest radiograph on admission showed some consolidation in the left mid zone but was otherwise normal. At bronchoscopy, a dark red mass was seen in the left main bronchus. This was thought to represent a tumour but a biopsy revealed normal bronchial mucosa and subsequent examinations of the bronchial tree were normal. It was therefore concluded that the mass was a blood clot. Scintigraphy revealed bilateral perfusion defects (Fig. 1) with normal ventilation and a diagnosis of pulmonary embolism was made. The patient was anti-coagulated and discharged from hospital. Three months later she was readmitted with a further haemoptysis. On examination, there was a loud second heart sound and an ejection systolic murmur in the pulmonary area. A right heart catheter study revealed a systolic pulmonary artery pressure of 70 mmHg. A diagnosis of pulmonary hypertension secondary to thrombo-embolic disease was made and she was referred to Papworth Hospital for further assessment. A pulmonary'arteriogram revealed a filling defect in a branch of the left basal pulmonary artery with almost complete occlusion of the remaining branches of the left pulmonary artery. The right basal pulmonary artery was also occluded (Figs 2 and 3). A limited contrast enhanced CT scan revealed a soft tissue mass occluding the left main pulmonary artery (Fig. 4). Both investigations were interpreted as showing proximal pulmonary artery occlusion due to thrombus and a thoracotomy was performed with a view to undertaking a pulmofiary endarterectomy. At surgery, a mass was present at the left hilum and the left pulmonary artery was virtually occluded by tumour arising from within. The tumour was deemed unreseetable and a biopsy taken prior to closure. The biopsy revealed a sarcoma of smooth muscle origin. Only then, in the light of the histological, angiographic and surgical appearances was. the correct diagnosis of a pulmonary artery leiomyosarcoma made. As local excision was clearly impossible, the patient was offered heart/lung transplantation. This was subsequently performed as further CT scans of the head, thorax and abdomen showed no evidence of metastases. After initial encouraging progress, the patient died 4 months following the operation from overwhelming cytomegalovirus and aspergillus infection. Just prior to death, a repeat CT scan revealed evidence of Correspondence to: P.D. Britton, Department of Radiology, Papworth Hospital, Papworth Everard, Cambridge.
Fig. 2-Case 1. Pulmonary arteriogram showing a filling defect in a branch of the left basal pulmonary artery with almost complete occlusion of the remaining branches of the left pulmonary artery. The right basal pulmonary artery is also occluded.
recurrent tumour in the posterior mediastinum. This was confirmed at post-mortem. Case 2. A 27-year-old female was admitted as an emergency following an episode of loss of consciousness lasting 15 minutes. She had a cough of six weeks duration and more recently had noticed some right sided pleuritic chest pain. A chest radiograph on admission revealed multiple pulmonary nodules in the right lung (Fig. 5). On auscultation, there was
PRIMARY PULMONARY ARTERY SARCOMA
93
Fig. 5-Case 2. Chest radiograph taken on admission to hospital showing multiple pulmonary nodules in the right lung (arrows).
Fig. 3-Case 1. An enlarged view of the left hilum showing the filling defect in a branch of the left basal pulmonary artery. a loud pulmonary ejection murmur and an echocardiogram demonstrated an echogenic mass attached to the underside of the pulmonary valve. A percutaneous Trucut lung biopsy of one of the nodules revealed a spindle cell sarcoma and monoclonal antibodies indicated a smooth muscle origin. The histological and echocardiographic appearances
'Fig. 6 Case 2. Pulmonary arteriogram. There are large filling defects in both proximal pulmonary arteries.
Fig. 4-Case 1. Contrast enhanced CT scan just below the level of the carina. The left pulmonary artery is occluded by a soft tissue mass (arrows).
were felt to be in keeping with a diagnosis of pulmonary artery sarcoma. The patient was referred to Papworth Hospital for assessment and possible surgery. A pulmonary arteriogram showed large filling defects in both main pulmonary arteries (Fig. 6). As her presentation was prior to the institution of the heart/lung transplantation programme, surgery was not deemed feasible in view of the degree of tumour spread. The patient was discharged and subsequently died.
94
CLINICAL RADIOLOGY
DISCUSSION Patients with primary pulmonary artery sarcoma vary widely in age with a mean of 52 years. There is a slight female preponderance of 1.3:1. Presenting symptoms usually consist of cough, chest pain and dyspnoea. Haemoptysis, as in Case one, and syncope, Case two, are less common, occurring in 39% and 20% of patients respectively. Auscultation commonly reveals a systolic m u r m u r (68%). The chest radiograph m a y be normal but usually exhibits one or more abnormalities, the commonest being either solitary or multiple pulmonary nodules (59%). Other changes include proximal pulmonary artery enlargement (28%), areas of oligaemia (24%) or cardiomegaly (35%) (Van D a m m e et al., 1986; Lyerly et al., 1986; de Smet et al., 1986; Berg et al., 1987;Schermoly et al., 1987; Verhaert et al., 1987; Promisloff et al., 1988). Ventilation/perfusion lung scintigrams usually show multiple perfusion defects indistinguishable from pulmonary thromboembolic disease. The defects tend to remain unchanged on serial scans, which is not customary with most examples of pulmonary thrombo-embolic disease. Two dimensional echocardiography commonly indicates right ventricular strain only and positive identification of the tumour as an echogenic mass in the pulmonary outflow tract has only once been previously described (Wright et al., 1983). A variety of appearances have been described at pulmonary arteriography; the commonest being one or more obstructing intraluminal filling defects in the proximal pulmonary arteries. This, however may be identical to the appearance seen with thrombo-embolic disease. Arteriographic appearances more specific to the diagnosis include lobulation of the intraluminal filling defects or even pedunculation with a 'to and fro' motion of the tumour which is best seen using cineangiography (Hynes et al., 1982). A smooth tapering of the pulmonary artery with distal pruning has been described due to a plaque-like, rather than polypoid, tumour growing along the intima (Schermoly et al., 1987). The CT appearances, described in seven patients, are those of a soft tissue mass filling the proximal pulmonary arteries (Van D a m m e et al., 1986). The appearances are indistinguishable from occlusion due to thrombus, unless there is evidence of tumour spread elsewhere, such as the presence of pulmonary nodules, pleural deposits or lymphadenopathy. The difficulty in making the diagnosis is illustrated by the fact that in 60% of the cases reported the diagnosis was only made at post-mortem and at thoracotomy in the majority of the remainder. Prognosis is usually very p o o r with a mean survival after the onset of symptoms of one year. A variety of
treatment has been instituted; mainly local surgical excision, with or without pneumonectomy, either alone or in combination with chemotherapy or radiotherapy. However of the 42 patients diagnosed ante-mortem just under three quarters died within the first year following treatment. Treatment with chemotherapy or radiotherapy alone carries an even worse prognosis and the few longer term survivors have all been treated surgically with or without adjuvant therapy. There have been no previously reported cases of treatment with heart/lung transplantation, although it offers the possibility of cure for patients whose tumour is localised to the pulmonary arteries. This is, however, dependent on early correct diagnosis, for which the major obstacle is the extreme rariety of the condition, and this will only be overcome with greater clinical and radiological awareness. Acknowledgements.I would like to thank Dr C. D. R. Flower for his advice in the preparation o f this paper. I would also like to thank Mr T. English and M r J. Wallwork for their permission to report these cases and Dr T. W. Higgenbottom under whose care the first patient was referred. REFERENCES Berg, G A , Hamid, BNA, Kenyon, W E & Drakely, M J (1987). Primary
pulmonary artery sarcoma: intra-operative similarityto pulmonary embolus. Postgraduate Medical Journal, 63, 389-391. Hynes, JK, Smith, HC, Holmes, DR, Edwards, WD, Evans, WD, Evans, TC & Orszulak, TA (1982). Preoperative angiographic diagnosis of primary sarcoma of the pulmonary artery. Circulation, 66, 672-674. Lyerly, HK, Reeves, JG & Sabiston, DC (1986). Management of primary sarcomas of the pulmonary artery and reperfusion intrabronchial haemorrhage. Surgery Gynaecology & Obstetrics, 163, 291-301. Mandelstamm, M (1923). Uber primare Neubildungen des Herzens. Virchows Archiv. A Pathological Anatomy and Histology, 245, 43 54. Promisloff, RA, Segal, SL, Lenehner, GS, Cichelli, AV, Wendell, G & Aaronsen, G (1988). Sarcoma of the pulmonary artery. Chest, 92, 207 208. Schermoly, M, Overman, J & Pingelton, SK (1987). Pulmonary artery sarcoma-unusual pulmonary angiographic findings-A case report. Angiology, 38, 617-621. de Smet, JM, Dieudonne, P, Contu, E, Le Clerc, JL, Goffin, Y & de Boelpape, C (1986). Pulmonary artery leiomyosarcoma treated surgically. Thoracic & Cardiovascular Surgeon, 34, 98-99. Van Damme, H, Vaneerdeweg, W & Schoofs, E (1986). Malignant fibrous histiocytoma of the pulmonary artery. Annals of Surgery, 205, 203-207. Verhaert, J, Van Meerbeeck, J, Vander Sande, J, Dion, R, Bourgois, N Ceelen, T & Minette, A (1987). Malignant fibrous histioeytoma of the pulmonary artery. European Journal of Respiratory Disease, 71, 321-323. Wright, EC, Wellons, HA & Martin, RP (1983). Primary pulmonary artery sarcoma diagnosed non invasivelyby two-dimensionalechocardiography. Circulation, 67, 459-462.
Primary Pulmonary Artery Sarcoma A Report of Two Cases, with Special Emphasis on the Diagnostic Problems P. D . B R I T T O N
Department of Radiology, Papworth Hospital, Cambridge Two cases of primary sarcoma of the pulmonary artery are presented. The variable clinical and radiographic features of this rare tumour are described with particular emphasis on its ability to mimic pulmonary thrombo-embolic disease.
P r i m a r y p u l m o n a r y a r t e r y s a r c o m a is a n u n c o m m o n t u m o u r a n d s i n c e its first d e s c r i p t i o n b y M a n d e l s t a m m (1923) o n l y 105 c a s e s h a v e b e e n r e p o r t e d i n t h e l i t e r a t u r e . Although histologically the tumours are very variable, w i t h o v e r 25 d i f f e r e n t t y p e s d e s c r i b e d , g r o s s a p p e a r a n c e s and behaviour are remarkably similar. The tumour almost invariably arises in the main pulmonary artery and spreads peripherally; retrograde spread involving the p u l m o n a r y v a l v e a n d r i g h t v e n t r i c l e is less c o m m o n . T u m o u r is u s u a l l y c o n f i n e d t o t h e t h o r a x a l t h o u g h d i s t a n t spread to the brain and abdomen has been reported. P r e s e n t a t i o n is u s u a l l y d u e t o o c c l u s i o n o f t h e p u l m o n a r y vasculature and right ventricular outflow obstruction.
Fig. 1-Case 1. Anterior view of perfusion lung scintigram showing marked reduction in perfusion throughout the left lung and further perfusion defects in the right lower lobel
CASE REPORTS
Case 1. A 34-year-old female presented with acute haemoptysis and a recent history of shortness of breath. The chest radiograph on admission showed some consolidation in the left mid zone but was otherwise normal. At bronchoscopy, a dark red mass was seen in the left main bronchus. This was thought to represent a tumour but a biopsy revealed normal bronchial mucosa and subsequent examinations of the bronchial tree were normal. It was therefore concluded that the mass was a blood clot. Scintigraphy revealed bilateral perfusion defects (Fig. 1) with normal ventilation and a diagnosis of pulmonary embolism was made. The patient was anti-coagulated and discharged from hospital. Three months later she was readmitted with a further haemoptysis. On examination, there was a loud second heart sound and an ejection systolic murmur in the pulmonary area. A right heart catheter study revealed a systolic pulmonary artery pressure of 70 mmHg. A diagnosis of pulmonary hypertension secondary to thrombo-embolic disease was made and she was referred to Papworth Hospital for further assessment. A pulmonary'arteriogram revealed a filling defect in a branch of the left basal pulmonary artery with almost complete occlusion of the remaining branches of the left pulmonary artery. The right basal pulmonary artery was also occluded (Figs 2 and 3). A limited contrast enhanced CT scan revealed a soft tissue mass occluding the left main pulmonary artery (Fig. 4). Both investigations were interpreted as showing proximal pulmonary artery occlusion due to thrombus and a thoracotomy was performed with a view to undertaking a pulmofiary endarterectomy. At surgery, a mass was present at the left hilum and the left pulmonary artery was virtually occluded by tumour arising from within. The tumour was deemed unreseetable and a biopsy taken prior to closure. The biopsy revealed a sarcoma of smooth muscle origin. Only then, in the light of the histological, angiographic and surgical appearances was. the correct diagnosis of a pulmonary artery leiomyosarcoma made. As local excision was clearly impossible, the patient was offered heart/lung transplantation. This was subsequently performed as further CT scans of the head, thorax and abdomen showed no evidence of metastases. After initial encouraging progress, the patient died 4 months following the operation from overwhelming cytomegalovirus and aspergillus infection. Just prior to death, a repeat CT scan revealed evidence of Correspondence to: P.D. Britton, Department of Radiology, Papworth Hospital, Papworth Everard, Cambridge.
Fig. 2-Case 1. Pulmonary arteriogram showing a filling defect in a branch of the left basal pulmonary artery with almost complete occlusion of the remaining branches of the left pulmonary artery. The right basal pulmonary artery is also occluded.
recurrent tumour in the posterior mediastinum. This was confirmed at post-mortem. Case 2. A 27-year-old female was admitted as an emergency following an episode of loss of consciousness lasting 15 minutes. She had a cough of six weeks duration and more recently had noticed some right sided pleuritic chest pain. A chest radiograph on admission revealed multiple pulmonary nodules in the right lung (Fig. 5). On auscultation, there was
PRIMARY PULMONARY ARTERY SARCOMA
93
Fig. 5-Case 2. Chest radiograph taken on admission to hospital showing multiple pulmonary nodules in the right lung (arrows).
Fig. 3-Case 1. An enlarged view of the left hilum showing the filling defect in a branch of the left basal pulmonary artery. a loud pulmonary ejection murmur and an echocardiogram demonstrated an echogenic mass attached to the underside of the pulmonary valve. A percutaneous Trucut lung biopsy of one of the nodules revealed a spindle cell sarcoma and monoclonal antibodies indicated a smooth muscle origin. The histological and echocardiographic appearances
'Fig. 6 Case 2. Pulmonary arteriogram. There are large filling defects in both proximal pulmonary arteries.
Fig. 4-Case 1. Contrast enhanced CT scan just below the level of the carina. The left pulmonary artery is occluded by a soft tissue mass (arrows).
were felt to be in keeping with a diagnosis of pulmonary artery sarcoma. The patient was referred to Papworth Hospital for assessment and possible surgery. A pulmonary arteriogram showed large filling defects in both main pulmonary arteries (Fig. 6). As her presentation was prior to the institution of the heart/lung transplantation programme, surgery was not deemed feasible in view of the degree of tumour spread. The patient was discharged and subsequently died.
94
CLINICAL RADIOLOGY
DISCUSSION Patients with primary pulmonary artery sarcoma vary widely in age with a mean of 52 years. There is a slight female preponderance of 1.3:1. Presenting symptoms usually consist of cough, chest pain and dyspnoea. Haemoptysis, as in Case one, and syncope, Case two, are less common, occurring in 39% and 20% of patients respectively. Auscultation commonly reveals a systolic m u r m u r (68%). The chest radiograph m a y be normal but usually exhibits one or more abnormalities, the commonest being either solitary or multiple pulmonary nodules (59%). Other changes include proximal pulmonary artery enlargement (28%), areas of oligaemia (24%) or cardiomegaly (35%) (Van D a m m e et al., 1986; Lyerly et al., 1986; de Smet et al., 1986; Berg et al., 1987;Schermoly et al., 1987; Verhaert et al., 1987; Promisloff et al., 1988). Ventilation/perfusion lung scintigrams usually show multiple perfusion defects indistinguishable from pulmonary thromboembolic disease. The defects tend to remain unchanged on serial scans, which is not customary with most examples of pulmonary thrombo-embolic disease. Two dimensional echocardiography commonly indicates right ventricular strain only and positive identification of the tumour as an echogenic mass in the pulmonary outflow tract has only once been previously described (Wright et al., 1983). A variety of appearances have been described at pulmonary arteriography; the commonest being one or more obstructing intraluminal filling defects in the proximal pulmonary arteries. This, however may be identical to the appearance seen with thrombo-embolic disease. Arteriographic appearances more specific to the diagnosis include lobulation of the intraluminal filling defects or even pedunculation with a 'to and fro' motion of the tumour which is best seen using cineangiography (Hynes et al., 1982). A smooth tapering of the pulmonary artery with distal pruning has been described due to a plaque-like, rather than polypoid, tumour growing along the intima (Schermoly et al., 1987). The CT appearances, described in seven patients, are those of a soft tissue mass filling the proximal pulmonary arteries (Van D a m m e et al., 1986). The appearances are indistinguishable from occlusion due to thrombus, unless there is evidence of tumour spread elsewhere, such as the presence of pulmonary nodules, pleural deposits or lymphadenopathy. The difficulty in making the diagnosis is illustrated by the fact that in 60% of the cases reported the diagnosis was only made at post-mortem and at thoracotomy in the majority of the remainder. Prognosis is usually very p o o r with a mean survival after the onset of symptoms of one year. A variety of
treatment has been instituted; mainly local surgical excision, with or without pneumonectomy, either alone or in combination with chemotherapy or radiotherapy. However of the 42 patients diagnosed ante-mortem just under three quarters died within the first year following treatment. Treatment with chemotherapy or radiotherapy alone carries an even worse prognosis and the few longer term survivors have all been treated surgically with or without adjuvant therapy. There have been no previously reported cases of treatment with heart/lung transplantation, although it offers the possibility of cure for patients whose tumour is localised to the pulmonary arteries. This is, however, dependent on early correct diagnosis, for which the major obstacle is the extreme rariety of the condition, and this will only be overcome with greater clinical and radiological awareness. Acknowledgements.I would like to thank Dr C. D. R. Flower for his advice in the preparation o f this paper. I would also like to thank Mr T. English and M r J. Wallwork for their permission to report these cases and Dr T. W. Higgenbottom under whose care the first patient was referred. REFERENCES Berg, G A , Hamid, BNA, Kenyon, W E & Drakely, M J (1987). Primary
pulmonary artery sarcoma: intra-operative similarityto pulmonary embolus. Postgraduate Medical Journal, 63, 389-391. Hynes, JK, Smith, HC, Holmes, DR, Edwards, WD, Evans, WD, Evans, TC & Orszulak, TA (1982). Preoperative angiographic diagnosis of primary sarcoma of the pulmonary artery. Circulation, 66, 672-674. Lyerly, HK, Reeves, JG & Sabiston, DC (1986). Management of primary sarcomas of the pulmonary artery and reperfusion intrabronchial haemorrhage. Surgery Gynaecology & Obstetrics, 163, 291-301. Mandelstamm, M (1923). Uber primare Neubildungen des Herzens. Virchows Archiv. A Pathological Anatomy and Histology, 245, 43 54. Promisloff, RA, Segal, SL, Lenehner, GS, Cichelli, AV, Wendell, G & Aaronsen, G (1988). Sarcoma of the pulmonary artery. Chest, 92, 207 208. Schermoly, M, Overman, J & Pingelton, SK (1987). Pulmonary artery sarcoma-unusual pulmonary angiographic findings-A case report. Angiology, 38, 617-621. de Smet, JM, Dieudonne, P, Contu, E, Le Clerc, JL, Goffin, Y & de Boelpape, C (1986). Pulmonary artery leiomyosarcoma treated surgically. Thoracic & Cardiovascular Surgeon, 34, 98-99. Van Damme, H, Vaneerdeweg, W & Schoofs, E (1986). Malignant fibrous histiocytoma of the pulmonary artery. Annals of Surgery, 205, 203-207. Verhaert, J, Van Meerbeeck, J, Vander Sande, J, Dion, R, Bourgois, N Ceelen, T & Minette, A (1987). Malignant fibrous histioeytoma of the pulmonary artery. European Journal of Respiratory Disease, 71, 321-323. Wright, EC, Wellons, HA & Martin, RP (1983). Primary pulmonary artery sarcoma diagnosed non invasivelyby two-dimensionalechocardiography. Circulation, 67, 459-462.
