View Abstract

A4035 - Atypical Carcinoid Successfully Treated with Endobronchial Therapy
Author Block: K. Kongpakpaisarn1, S. Suchartlikitwong2, A. J. Schwalk3, W. Vitthikraivit4, R. Alalawi5; 1Internal Medicine, University of South Florida, Tampa, FL, United States, 2Texas Tech University Health Sciences Center, lubbock, TX, United States, 3Internal medicine/Pulmonary and critical care, Texas Tech University Health Sciences Center, Lubbock, TX, United States, 4Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States, 5BUMCP Lung Institute, Phoenix, AZ, United States.
Introduction: Bronchial neuroendocrine tumors (carcinoids or NETs) are a rare group of lung neoplasms in adults. These tumors arise from neuroendocrine cells in the bronchial mucosa. Lung NETs account for 1 to 2 percent of all lung tumors, are slow-growing and rarely produce neuropeptides. Patients are usually asymptomatic and often misdiagnosed.
Case description: A 61-year-old Caucasian male presented with a chronic productive cough. He had a 15 pack-year tobacco history. High-resolution chest CT showed left lower lobe airspace consolidation and dilated airways. He was diagnosed with localized bronchiectasis and was treated with rotating antibiotics. His symptoms improved but never resolved. He had no flushing, diarrhea, shortness of breath or wheezing. Five years later he developed hemoptysis and a bronchoscopy was performed. Bronchoscopy revealed a fungating endobronchial mass in the left mainstem bronchus near the origin of the left lower lobe. Endobronchial ultrasound was performed which showed no lymph node involvement. The mass was resected using endoscopic electrosurgery and the base treated with Neodymium yttrium-aluminium-garnet laser. Tumor histology revealed an atypical neuroendocrine tumor. Cells were positive for synaptophysin and chromogranin. Ki-67 was present in 25%. Octreotide scintigraphy showed localized disease activity in the left perihilar region. Further imaging showed no evidence of metastasis. He was diagnosed with stage 1 atypical lung neuroendocrine tumor. His symptoms were greatly improved after tumor removal. He was offered a pneumonectomy in view of the tumor location which he declined and opted for watchful management.
Discussion: Lung NETs are more common in Caucasians and usually present in the fourth to sixth decades of life . Poorly-differentiated lung NETs, also known as small cell carcinoma (SCLC), are more prevalent and aggressive. Low and intermediate grade lung NETs, known as typical and atypical carcinoids respectively, are slow-growing and rare. Smoking seems to be most strongly associated with SCLC but not significantly with atypical or typical carcinoids. Carcinoid tumors can be centrally or peripherally located. Patients with central carcinoid tumors usually have symptoms related to airway obstruction such as coughing, wheezing, and recurrent infections. These symptoms can delay accurate diagnosis, as seen in our patient. Surgical resection is currently the only proven curative option for bronchial carcinoids. Endobronchoscopic resection can be safely used in select cases with good long-term outcomes.