Mid-term outcomes of a bio-artificial pleura composed of autologous dermal fibroblasts used to close intraoperative pulmonary air leaks caused by intraoperative pleural injury: A case report.

Introduction: The visceral pleura is a thin, serous membrane that closely covers the surface of the lung. The pleura is injured or ruptured, causing air to accumulate in the thoracic cavity and the lung to collapse. Increased pleural pressure due to lung air leaks (LALs) from the lung can have serious effects. LALs are frequently observed due to pleural injury caused by lung resection. Postoperative LALs prolongs hospital stay and has a significant impact on patients' postoperative quality of life. Based on the above background, we developed and reported the effectiveness of dermal fibroblast sheet (DFS) as a bio-artificial pleura for closing LALs caused by intraoperative pleural injury in humans for the first time in a clinical study. There are no mid-term reports of bio-artificial pleura created using tissue engineering. In this study, we report the safety of bio-artificial pleural transplantation using cultured autologous DFS for pleural injury in two cases. Previous study and case presentation: Two of the five patients who met the criteria and underwent LAL closure using a bio-artificial pleura between May 2016 and March 2018 were followed up mid-term. Although the criteria included a 6-month monitoring period after LAL closure, these two patients continued to visit our hospital beyond the monitoring period for treatment of other comorbid conditions. Case 1. A male in his 40s who was receiving long-term steroid therapy for Takayasu's disease and underwent thoracoscopic lung wedge resection for a benign lung tumor in the left anteromedial basal segment. During surgery, the minor LALs from the resection margins with an automatic stapler were closed with a bio-artificial pleura, specifically, a total of three DFSs. During the patient's 51-month follow-up, no LAL recurrence, tumor development, infiltration, and fibrogenesis were observed. Case 2. A female patient in her 70s had bullae associated with combined pulmonary fibrosis and emphysema (CPFE). Thoracoscopic bullectomy of the left lower lobe was performed, and the major LALs were closed intraoperatively with a bio-artificial pleura consisting of a total of eight DFSs. She was readmitted for contralateral pneumonia 2 months after surgery. During a follow-up period of 82 months, no LAL recurrence and tumor development was observed in the operated left lung. However, chest CT revealed slowly progressing CPFE lesions. Conclusions: This report of two cases demonstrated the mid-term safety of bio-artificial pleural transplantation using cultured autologous DFS for pleural injury.