Pulmonary nodule caused by an alveolar adenoma of the lung

Abstract

Alveolar adenomas of the lung may be a rare cause of solitary coin lesions on chest radiographs. We report a case of this neoplasm, describe its morphological and immunohistochemical characteristics and give further evidence that alveolar adenomas of the lung represent a benign proliferation of both the alveolar epithelium and the septal mesenchyme.

Alveolar adenoma of the lung: a clinicopathological description of a case of this very unusual tumour

“…Using strict criteria of histology, histochemistry, and immunohistochemical studies, as defined by Burke et al in 1999, less than 25 cases of true alveolar adenoma have been reported. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] These tumours have been reported in all major geographical areas of the world and have been found in all races. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Most patients are middle aged to elderly, with a slight female predominance.…”

“…Transbronchial biopsies, bronchial washings, and fine needle transcutaneous CT guided biopsies have been non-diagnostic in these cases. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] In most instances, these tumours have been surgically excised using a simple wedge resection of the lung. Frozen sections, when reported, have either been inconclusive or suspicious of alveolar adenoma, without being diagnostic.…”

“…1 Macroscopic findings of previously reported cases have been consistent and similar to our own. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] In contrast, the histopathology is quite variable with the exception of being well demarcated and multicystic. Microscopically, the cystic spaces dominate the picture, with the larger cysts usually concentrated in the middle of the tumour.…”

“…From the microscopic appearance and immunohistochemical studies, most authors agree that the epithelial component of this tumour is derived from type 2 pneumocytes. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] The interstitial component varies from sparse to exuberant. It usually contains collagen fibrils and prominent spindle or oval shaped cells.…”

“…1-3 Some authors have suggested that alveolar adenomas of the lung may represent the benign counterpart of bronchioloalveolar carcinoma. 4 Our case study adds to the current literature a patient with a full clinical evaluationincluding for the first time to our knowledge a preoperative positron emission tomography (PET) scan-the description of gross, histological, histochemical, and immunohistochemical findings, and a one and a half year follow up after resection.…”