Spontaneous Regression of Non-Small Cell Lung Cancer in a Patient with Idiopathic Pulmonary Fibrosis: A Case Report
A 62-year-old man complaining of dyspnea was referred to our hospital in November 2011. He had a 70 pack-year history of smoking, and a history of diabetes mellitus. Chest computed tomography (CT) revealed a diffuse subpleural reticular pattern and honeycombing in both lungs without mass-like lesions, suggesting IPF ().\nA follow-up chest CT was performed in May 2012. The image revealed a newly developed, 3.2×2.3 cm, irregular mass widely abutting pleura in the left upper lobe (). The CT also revealed multiple enlarged lymph nodes in the paratracheal, subcarinal, prevascular, subaortic, hilar and supraclavicular areas (). Similarly, 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) showed multiple lymph node enlargements with increased FDG uptake in the hilar, subcarinal, paratracheal, subaortic, prevascular and supraclavicular areas (). Carcinoembryonic antigen was 2.41 ng/mL (normal range, <5.0) and cytokeratin 19 fragment was 7.58 ng/mL (normal, <3.3). Endobronchial ultrasound-guided transbronchial needle aspiration and CT-guided fine needle biopsy in June 2012 revealed no malignancy in the left upper lobe tumor, but metastatic NSCLC in a subcarinal lymph node, a right lower paratracheal lymph node, and a left lower paratracheal lymph node (). Other metastatic work-up including brain magnetic resonance imaging and whole body bone scan was negative. Consequently, the patient was diagnosed with NSCLC (T2N3M0, stage IIIC). The patient declined palliative chemotherapy, and was discharged from the hospital without treatment.\nA follow-up outpatient chest CT was performed in October 2012. This image revealed the disappearance of the primary tumor in the subpleural area of the left upper lobe, and a marked decrease in the size of the multiple metastatic lymph nodes in the hilar, subcarinal, paratracheal, subaortic, prevascular and supraclavicular areas (). Follow-up chest CT in January 2013 showed no significant change in primary tumor or metastatic lymph nodes.