Placental Lung Transmogrification presenting as voluminous symptomatic lobar emphysema

Hintergrund: Placental lung transmogrification (PLT) is a rare pathological entity which describes the occurrence of a placental histologic pattern within the lung. Treatment recommendations are scarce due to only few cases described up to now. Clinical signs range from asymptomatic to acute pneumothorax, but classically, patients present with cough and progressive dyspnea. The disease induces bullous emphysema and cystic transformation of the lung. Surgical removal is the treatment of choice, but treatment modalities are differently reported. We here describe a rare case of PLT in the light of the current literature.

Ergebnis: A 63 year old man presented with progressive worsening of dyspnea. Spirometry tests showed impaired pulmonary function. A CT confirmed increasing hyperinflation of the right lower lobe as well as bullae that had increased in size and number over time and displaced the upper lobe and the mediastinum. A right lower lobectomy was performed. The specimen showed cystic malformations and multiple subpleural bullae. Histopathological exam revealed interstitial cysts as well as papillar and villous structures. Immunohistochemical staining showed positive CD10 and positive Cimentin but negative SMA, Desmin, HBM-45, Melan-A and MITF. These lesions were found consistent with a bullous placental malformation.

Schlussfolgerung: Differential diagnoses for pulmonary cystic lesions include tuberous sclerosis, lymphangioleiomyomatosis (LAM), alpha-1-antitrypsin deficiency and congenital cyst adenomatoid malformation (CCAM). Performing a pneumonectomy is unnecessarily compromising normal lung tissue. Bullectomy only is not eliminating the potential trigger focus of infection and does not necessarely improve lung function. As PLT is usually restricted to one lobe, lobectomy is the treatment of choice and the receptor CD10 seems to be specific as a marker to identify PLT.