INTRODUCTION: Patients with Pulmonary Hyalinizing Granuloma (PHG) usually present with lung masses diagnosed incidentally on chest radiographs (CXR). However, their appearance on a 18-FDG Positron Emission Tomography (PET) scan in adults is not known and is reported here along with the association with deep venous thrombosis (DVT) in the absence of any pro-coagulant risk factors.
CASE PRESENTATION: An 83 year old obese female with a sixty pack-year smoking history was referred for evaluation of an incidental finding on chest radiograph. Her only respiratory complaint was an occasional non-productive cough. Her past medical history was significant for recurrent deep venous thrombosis (DVT) without any predisposing factors. She retired from an office job and denied any hazardous environmental exposure.Physical examination did not reveal any evidence of clubbing, pallor, cyanosis or any pulmonary abnormality. Pulmonary function testing revealed mild restriction, explained by her obesity.Chest x-ray (CXR) showed a large mass in the right mid lung and another mass at the right apex highly suspicious for a neoplastic process. These were not present on a CXR from two years ago. Computed Tomography (CT) scan of the chest showed a large pulmonary mass within the anterior segment of the right upper lobe measuring 6.3 × 3.8 × 5.3 cm with peripheral spiculation and extension to the pleura. Two additional spiculated nodules in the right upper lobe and one in the left upper lobe were also found. A PET scan revealed that all lung masses were strongly FDG-avid, consistent with malignancy and probably multi-centric pulmonary malignancy. The patient underwent two non-diagnostic flexible bronchoscopy procedures along with multiple transbronchial biopsies and transbronchial needle aspiration of the two right sided masses. Six CT guided core-needle lung biopsies were then obtained and all contained dense, lamellar or “ropy” keloid-like collagen bundles arranged in a haphazard pattern. The biopsies lacked significant necrosis, necrotizing granulomas or epithelioid granulomas. Congo red stain with polarization was also negative for amyloid. The diagnosis of PHG was made. A complete hypercoagualable workup was done but no underlying abnormalities were found including a negative lupus anticoagulant. The patient was maintained on warfarin and followed clinically and with serial CT scans for one year after the initial presentation. She remained totally asymptomatic and had no change in the lung masses.
DISCUSSIONS: PHG was coined by Engleman et al. to describe the specific histological appearances observed in a series of pulmonary nodules with unknown etiology.1 Nodules with spiculated margins and cavitation have been reported, but their appearance on a PET scan has not been described in adults.1 The strongly avid appearance of PHG on a PET scan may lead to multiple and un-necessary invasive procedures in the pursuit of a diagnosis of malignancy. Although a case of PHG associated with DVT in the presence of lupus anticoagulant has been reported,2 our patient developed DVT without any underlying coagulation abnormalities. This may point towards a direct association of DVT with PHG, something that needs to be confirmed in future reports.
CONCLUSION: PHG may present as strongly avid (hot) lesions on a PET scan. It can be associated with DVT even in the absence of lupus anticoagulant and other coagulation abnormalities.
DISCLOSURE: Hamed Mataria, No Financial Disclosure Information; No Product/Research Disclosure Information