Commentary: Pneumonectomy for resection of pulmonary mucormycosis: Enough is never too much.

Robert E. Merritt, MD

Pulmonary mucormycosis is a locally invasive fungal infection that can be fatal. Optimal management includes systemic antifungal therapy and aggressive surgical debridement of involved lung tissue.

See Article page 81.

Pulmonary mucormycosis (PM) is a relatively rare and fatal fungal infection that occurs primarily in immunocompromised patients with underlying medical conditions, such as diabetes, malignancy, and solid-organ transplantation., Pulmonary infection with mucormycosis is caused by inhalation of spores resulting in fungal pneumonia and resultant necrosis and infarction of lung tissue. PM can spread directly or hematogenously to surrounding thoracic structures in the mediastinum. Despite improved treatments, the mortality rate for PM is 96% for disseminated disease and 76% for pulmonary disease., The diagnosis of PM requires a high degree of clinical suspicion, and clinical, radiographic, bronchoscopic, and microbiologic data should be used to arrive at a timely diagnosis. Effective management of PM remains difficult and challenging due to the local invasiveness of mucormycosis and the paucity of evidence-based data to guide the optimal clinical management and decision-making. Because PM is relatively rare, most published reports describing the clinical outcomes for PM consist of primarily small clinical series and case reports.

The current cornerstone of treatment for PM is typically amphotericin B and aggressive surgical debridement of the fungal mass. The current clinical evidence on treatment outcomes indicate that patients treated with combined medical and surgical therapies have demonstrated better outcomes compared with patients who did not undergo surgical resection., In their case report, Van Octhen and colleagues described a case of PM that was managed with a right pneumonectomy due to extensive infiltration of PM into the right hilum. This case report perfectly highlights the aggressive local invasiveness of PM and the importance of timely and aggressive surgical resection. Although most reported surgical resections for PM involve lobectomy, there are reported cases that required pneumonectomy. Regardless of the extent of surgical resection required for PM, the postoperative complications, hospital length of stay, intraoperative blood loss, and mortality are relatively high in reported series., The presence of tissue necrosis, inflammation, and active infection associated with PM will certainly increase the risk of bronchial stump dehiscence and subsequent bronchopleural fistula. As described by Van Octhen and colleagues, coverage of the bronchial closure with a vascularized muscle flap, such as intercostal muscle, serratus anterior, or latissimus dorsi muscle, should always be considered with lobectomy or pneumonectomy for surgical resection of PM to mitigate the greater risk of postoperative bronchopleural fistula. As previously described, vascular invasion, tissue necrosis, active inflammation, and adhesions are typically encountered during surgical resection for PM, which contribute to longer operative times and more frequent intraoperative transfusions. In-hospital mortality for patients undergoing surgical resection for PM is as high as 14.5% to 16.7%., Apart from small case series and case reports, there is minimal evidence-based data to guide surgeons on appropriate patient selection and surgical approach for the management of PM. Based on what is currently known regarding PM, there some established clinical guidelines for the management of PM, which include correction of the underlying predisposing medical condition, rapid diagnosis with imaging and tissue diagnosis, systemic antifungal therapy, and early aggressive surgical debridement with either lobectomy or pneumonectomy.