Horseshoe kidney

INTRODUCTION: Pulmonary artery sarcoma is a rare vascular tumor. The diagnosis is rarely made antemortem. We present an unusual case of a pulmonary artery mass in a patient with a horseshoe kidney that was diagnosed via an endovascular biopsy procedure.

CASE PRESENTATION: A 37-year-old healthy man developed chest discomfort, worsening shortness of breath, and palpitations over a ten month period. He was treated for recurrent episodes of bronchitis. With progressive dyspnea on exertion to the point he was unable to walk across the room without significant shortness of breath, a repeat echocardiogram now showed a large solid mass (5 cm by 3 cm) in the main pulmonary artery and right ventricular dysfunction. A computed tomography scan revealed a large filling defect in the main pulmonary artery and was felt to be a saddle embolus. Additionally, a horseshoe kidney was noted. Upon transfer to our institution, a cardiac MRI scan confirmed the irregularly shaped mass in the pulmonary artery. Due to the chronicity of his symptoms, a tumor of the pulmonary artery was suspected. A pulmonary artery angiogram revealed the mass obstructing 80% of the lumen of the main pulmonary artery. An endovascular biopsy was performed then using myocardial biopsy forceps. Surgical pathology and cytology revealed a high grade sarcoma. No metastatic disease was detected. He underwent surgical excision with reconstruction of the pulmonary artery two weeks later and is alive one year later.

DISCUSSIONS: Antemorem diagnosis of a pulmonary artery sarcoma is unusual. In such instances, the diagnosis is usually suspected and confirmed only at the time of surgical excision. We describe a case in which the diagnosis was suspected and confirmed via an endovascular biopsy. Pulmonary artery sarcomas are rare malignant tumors with about 138 cases reported in the literature. The clinical presentation may include chest pain, cough, hemoptysis, or dyspnea. Various laboratory studies will assist with the diagnosis. An echocardiogram may show the lesion in the pulmonary artery and right ventricular strain and a computed tomography scan may also show a filling defect in the pulmonary artery. In many instances a pulmonary embolism is suspected. Cardiac MRI has rarely been used in the diagnosis of]pulmonary artery tumors but characteristics showing signals consistent with tissue compared to thromboembolism are noted. Pulmonary angiography will help to define the extent of the lesion. Unfortunately none of the imaging studies can confirm the diagnosis. A biopsy can be difficult to obtain unless obtained by surgical intervention. While chronic thromboembolism was considered, the progressive nature of the dyspnea over a ten month period in conjunction with the MRI findings led us to suspect a pulmonary artery tumor as the cause for the patient's symptoms. During the pulmonary angiography, a sample of the mass was obtained using myocardial biopsy forceps using fluoroscopic guidance without complications. Interestingly, a horseshoe kidney was found in this patient. Various anomalies of other body systems (e.g. Wilms' tumor, Renal cell carcinoma, Renal sarcoma, and Carcinoid tumor) have been reported and in this young patient, a relationship between these two diseases could be suspected.

CONCLUSION: We present an unusual case of a pulmonary artery sarcoma (associated with a horseshoe kidney) that was diagnosed prior to surgery via an endovascular biopsy procedure. This procedure was performed safely and afforded the diagnosis with minimal morbidity. Surgical intervention could then be performed with knowledge of the diagnosis prior to the intervention 'allowing for appropriate therapy to be afforded.

REFERENCES:

(1) JM Parish et al. Pulmonary artery sarcoma:Clinical features Chest 1996 110: 1480-1488.

(2) Joseph E. Cox et al. Pulmonary artery sarcomas: A review of clinical and radiological features. Journal of Computer Assisted Tomography 1997 21(5):750-755

DISCLOSURE: Rajashekar Adurty, None.

Rajashekar Adurty MD * Brian Carlin MD Sanjay Godara MD Gustav Eles MD Donald Fisher MD Division of Pulmonary and Critical Care Medicine, Allegheny General Hospital, Pittsburgh, PA

COPYRIGHT 2005 American College of Chest Physicians
COPYRIGHT 2005 Gale Group