A 76-year-old man was seen for evaluation of abnormal findings on a chest x-ray film revealing pleura-based densities. He had a medical history of Hodgkin disease dating back to 1961, at which time he had received a 6-week course of radiation therapy. He had mild aortic stenosis and hypertension.
Three months before the current evaluation, this patient began to have dyspnea, fatigue, cough, and wheezing. His dyspnea was initially associated with vigorous exertion, but within a few months, it occurred with mild exertion. In addition, he had rib pain on the lower right side and anorexia along with a 25-pound weight loss. He had no fever, hemoptysis, or leg edema.
The patient's daily medications included hydrocodone for pain plus a β-blocker, aspirin, and triamterene. He had no known allergies. His social history was notable for smoking one pack of cigarettes per day for 45 years. He had worked as a sales technician for an aluminum manufacturing company and was unaware of having been exposed to asbestos. He denied doing vehicular brake work or engaging in any activity that might have put him at risk for asbestos exposure. He had no family history of lung disease.
On physical examination, the patient appeared chronically ill but in no acute distress. His systolic blood pressure was 125 mm Hg and diastolic blood pressure, 80 mm Hg; pulse rate, 90/min and regular; and respirations, 22/min. The findings from the head, eyes, ears, nose, and throat examination were unremarkable. His sinuses were nontender and his neck, supple. His trachea was midline, and he had restricted chest wall movement on the right side. He had decreased breath sounds and dullness to percussion at the base of the right lung. Cardiac rhythm was regular, with an aortic stenosis systolic murmur noted. Examination of the extremities revealed no clubbing, cyanosis, or lower leg edema.
Baseline spirometry revealed a forced vital capacity (FVC) of 1500 mL (41% of predicted), forced expiratory volume in 1 second (FEV1) of 1180 mL (49% of predicted), and FEV1/FVC of 78%, findings that are consistent with a restrictive ventilatory process.
Chest x-ray film revealed an apparent pleural effusion on the right side (
Figure 1); however, thoracentesis failed to obtain pleural fluid. A chest computed tomography (CT) scan was ordered and revealed a nodular pleura-based mass on the right side (
Figure 2).
The patient then underwent an open thoracoscopy with visualization of the pleural space and a pleural biopsy (
Figure 3). The biopsy revealed a malignant spindle-shaped cell neoplasm with mixed hypercellular and hypocellular areas that had collagenized foci. Nuclear atypia and mitotic figures were prominent, and a patchy lymphocytic infiltrate was present. The tumor was diffusely positive only for vimentin immunohistochemical stain. Tumor cells were negative for other immunohistochemical stains, including cytokeratin cocktail (high- and low-molecular-weight cytokeratin), calretinin, S100 stain, CD34, and cytokeratin 5/6. Outside pathologic consultation was required. The consultant's opinion was that in concert with a high clinical suspicion of mesothelioma, these patterns were consistent with a mixture of the desmoplastic and lymphohistiocytoid variants of sarcomatoid mesothelioma. It is hypothesized that the tumor was undifferentiated to the degree of losing expression of calretinin and cytokeratin, two usual components of mesothelial cells.
The patient was referred to the thoracic surgical and oncology division. Because of the advanced stage of his disease and the aggressive nature of this variant of malignant mesothelioma, his clinical course rapidly deteriorated and he died 3 months after diagnosis. He had not received surgical or chemotherapeutic treatment.