Pulmonary sclerosing pneumocytoma - approaching a solitary pulmonary nodule and the limitations of risk prediction models.

Our case is an asymptomatic, non-smoking, East Asian woman in her 40s presenting with a solitary pulmonary nodule (SPN). On imaging, the 1.7 cm solid SPN located in the left upper lobe, was rounded in morphology and moderately fluorodeoxyglucose avid. The clinical pretest probability of malignancy assessed by risk prediction models such as Brock (19.1%), Mayo Clinic (56.2%) and Herder (51.4%) was discordant. She underwent a percutaneous CT-guided needle biopsy, establishing a diagnosis of pulmonary sclerosing pneumocytoma (PSP). PSP is a rare benign lung neoplasm with indolent growth characteristics that has been described predominantly in non-smoking women. Our case illustrates the limitations of applying existing risk prediction models in Asia where the epidemiology and biology of lung cancer differ significantly from the Caucasian derivation cohorts. Additionally, the risk models do not account for tuberculosis, which is endemic in Asia and can mimic malignancy. Non-surgical lung biopsy remains useful in minimising unnecessary thoracotomy.

A Case of Mesenchymal Hamartoma of the Chest Wall in a 4-Month-Old Infant.

BACKGROUND Mesenchymal hamartoma of the chest wall is a rare benign lesion that typically presents in early infancy. However, the clinical presentation can be atypical, with imaging features that mimic infection or malignancy. Imaging combined with histopathology is essential in the diagnosis. A case of mesenchymal hamartoma of the chest wall in a 4-month-old infant is presented. CASE REPORT A 4-month-old infant had an incidental finding of a large right-sided chest wall mass. Initial imaging included thoracoabdominal ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). Histology of an initial open biopsy was inconclusive. The diagnosis of mesenchymal hamartoma was confirmed by histology of the resection specimen, which showed a benign, mixed, chondroid, mesenchymal, and cystic hamartoma with areas of calcification and ossification. CONCLUSIONS This case showed that the diagnosis of mesenchymal hamartoma of the chest wall, which is characterized by heterogeneous components, may require a combined approach for the diagnosis that includes imaging and histology. Increased clinical awareness of mesenchymal hamartoma in infants may help to guide the approach to the correct diagnosis and prevent unnecessarily radical treatment for this benign condition.