Development of pulmonary Langerhans cell histiocytosis in a patient with established adenocarcinoma of the lung.

Newly-appearing lung nodules on surveillance imaging in patients with pre-existing lung cancer can present a diagnostic dilemma when attempting to differentiate between metastatic disease, infection, and other inflammatory conditions. Here we report a case of an EGFR-/ALK-/BRAF+ metastatic adenocarcinoma patient who underwent lung biopsy for evaluation of upper-lobe predominant lung nodules revealed to represent pulmonary Langerhans cell histiocytosis (PLCH). The patient was a heavy smoker and admitted to increase her smoking habit after initially learning about her diagnosis with lung cancer. Interestingly, despite the association of both lung adenocarcinoma and PLCH with the BRAFV600E mutation in smokers, pyrosequencing of the patient's PLCH lesions was negative for this mutation. Co-occurrence of PLCH with lung cancer is extremely rare. While most reported cases of PLCH tend to precede the occurrence of lung cancer, a minority of cases appear after a diagnosis of lung cancer has already been established and are thought to represent a local immunologic reaction to the tumor. It is therefore postulated that the appearance of PLCH lesions in this patient's lungs is a result of her increase in cigarette smoking, possibly augmented by co-existence of adenocarcinoma.

Ten-year Single Center Experience of Pulmonary Carcinoid Tumors and Diagnostic Yield of Bronchoscopic Biopsy.

PURPOSE: Bronchoscopic biopsy of pulmonary carcinoid tumors has been controversial, and no study to date is dedicated to investigate diagnostic yield or safety. We reviewed our single center experience with pulmonary carcinoid tumors over a 10-year time period and assessed the diagnostic yield and safety of bronchoscopic biopsy of these tumors. METHODS: A retrospective analysis was conducted of all bronchopulmonary carcinoid tumors from January 2003 through January 2014 for patients treated at or referred to our tertiary care facility, including patient and tumor characteristics, diagnostic yield, and complications of bronchoscopy. RESULTS: Forty-nine patients with bronchopulmonary carcinoid tumors were identified. 75.5 % of our patients were female, and the median age was 60.7 years. 85.7 % patients were white, and 53.1 % were smokers. 83.7 % had typical carcinoid tumors or tumorlets, and 85.7 % had centrally located tumors. The median tumor size was 2.0 cm. Thirty patients underwent bronchoscopy for diagnostic evaluation. 76.7 % were diagnosed via bronchoscopic biopsy. Bronchoscopic yield was calculated at 65.7 % yield, and two complications of moderate to severe bleeding occurred with no emergent thoracotomies, transfusions, or deaths. No other complications occurred from bronchoscopy. CONCLUSION: The diagnosis of pulmonary carcinoid tumors via bronchoscopic biopsy is safe and effective, and bronchoscopy is recommended as the initial diagnostic modality for these tumors.