Placental Transmogrification of the Lung
A 31-year-old female patient presented with cough and mild dyspnea to the outpatient department. She had a history of being diagnosed with pulmonary tuberculosis 7 years ago, which she had completely recovered after 6 months of antituberculosis drug regimen. There was no other notable history. Dullness and decreased breathing sound at the left side was noted after auscultation. Complete blood count revealed no abnormal finding, and no acid-fast bacilli was discovered on the sputum culture test. Plain chest radiography showed giant bulla in the left lung and subsegmental consolidation in the left lower lung field. Chest computed tomography (CT) scan revealed the left upper lobe of the lung being replaced by bullae of various sizes, and subsegmental consolidation had broad contacted with bullae at the lingular segment of the left upper lobe (). The right lung showed no abnormality. The patient's pulmonary function test signified moderate obstructive respiratory failure. Wedge resection of the left lung using video-assisted thoracoscopy was performed under the preoperative diagnoses of giant bullae and pulmonary emphysema. During operation, the left lower lobe was found to be severely compressed by the bullae. Gross examination of the wedge resected lung was 15 × 9 × 4 cm in size with dilated giant bullae (). Spongiform emphysema was observed at the cut surface, and there were partial solid changes and fibrotic progression. Examination of the solidified sites by light microscope indicated general emphysematous changes with destruction of the alveolar wall in addition to numerous tissues replaced by structures similar to the chorionic villi. The villous structure was adjacent to, or in some cases adhered to, the destroyed alveolar wall and interlobular septa. Immunohistochemical staining of the epithelium lining the villous structure was partly positive for thyroid transcription factor-1, and the interstitial cells at the core was positive for CD-10, D2-40 and vimentin (). There was no human chorionic gonadotropin positive cell.\nThe chest tube was removed 8 days after surgery. Pathologic examination of the surgical specimen reported placental transmogrification of the lung. Chest CT scan was taken to rule out the possibility of remnant bullae or transmogrified tissue. The giant bullae at the left upper lobe were removed, but some fibrotic tissue still remained. Additional left upper lobectomy was planned to remove the remaining tissue in order to minimize recurrence. However, the patient did not complain of any symptoms and refused further operation. She was explained about the possibility of recurrence and scheduled visits to the outpatient clinic on a regular basis for follow-ups.