Desquamation Interstitial Pneumonia Presenting as a Solid Mass in the Lung: a Case Report.

Background: Desquamation interstitial pneumonia (DIP) is a rare type of idiopathic interstitial pneumonia. High resolution computed tomography (HRCT) shows ground glass opacities without the peripheral reticular opacities characteristic of usual interstitial pneumonia (UIP). Here we report a case of DIP presenting as a solid mass in the lung, which is rarely described in the literature.Case presentation: A 77-year-old man presented with dry cough and dyspnea on exertion for one month was admitted to our hospital. The lung CT scan showed there was a pulmonary mass in right lower lung and the patient was scheduled for surgery. He was a sculpture artist, non-smoker and the previous medical history included only mandatory spondylitis without other connective tissue diseases. Nine days post-last CT, the FDG PET/CT demonstrated the mass in the right lower lung was significantly hypermetabolic (SUV value=8.9) but inflammatory exudate could be observed around the mass. We gave antibiotics and performed CT-guided percutaneous lung biopsy. The result showed that there were a large number of macrophages in the alveolar cavity, alveolar epithelial type II cells hyperplasia in some areas and chronic inflammation was noted in the interstitium. Then the desquamative interstitial pneumonia was diagnosed. We gave the patient glucocorticoid therapy, then the patient's symptoms disappeared gradually and the lung CT showed that the pulmonary mass was disappeared.Conclusions: Our report illustrates the rare presentation of DIP. Furthermore, for the pulmonary mass, even if appeared hypermetabolic on PET/CT, it is still necessary to make a definite pathological diagnosis before operation, so as to reduce the damage to patients.

SMARCA4-deficient thoracic sarcoma revealed by metastasis to the small intestine: a diagnostic dilemma

SMARCA4-deficient thoracic sarcoma (SMARCA4-DTS) is a recently identified aggressive subtype of sarcoma. We present the case of a 44-year-old man who underwent a surgery for a perforated small intestine. Compued tomography scan revealed a tissular mediastino–pulmonary mass.Histopathological examination of the intestinal mass shown a malignant tumour with a typical epithelioid and rhabdoid cells, numerous mitoses and large necrosis. A large panel of immunohistochemistry revealed loss of SMARCA4 and SMARCA2 and allowed the diagnosis of SMARCA4-DTS. It is important to consider SMARCA4-deficient thoracic sarcoma in the differential diagnosis of tumours showing suggestive morphologic features in patients of all ages, especially in the case of metastasis associated with thoracic mass.