[Pulmonary neuroendocrine neoplasms]. / Neuroendokrine Neoplasien der Lunge.

The pulmonary neuroendocrine neoplasms originate from the enterochromaffin cells which are diffusely distributed in the body. The incidence of these tumors has increased significantly in recent decades due to the available diagnostics. They make up about 1-2% of all lung tumors and 20-30% of all neuroendocrine neoplasms. The current WHO classification from 2004 divides them into typical carcinoids (TC), atypical carcinoids (AC), large cell neuroendocrine carcinomas (LCNEC) and small cell carcinomas (SCLC). The major neuroendocrine biomarkers are chromogranin A, synaptophysin and CD56. TC have a low mitotic rate of <2 mitoses/2mm(2) (10 HPF), whereas the mitotic rate of the AC is 2-10 mitoses/2 mm(2) (10 HPF). The Ki-67 staining is helpful to distinguish typical and atypical carcinoids from the highly malignant LCNEC and SCLC. Clinically, the patient presents usually with cough, hemoptysis or bronchial obstruction. The occurrence of a carcinoid or Cushing's syndrome and a tumor-associated acromegaly are rare. Surgical resection with radical lymph node dissection is the treatment of choice for achieving long-term survival. Endoscopic resection of the endobronchial tumor growth is a good alternative for inoperable endobronchially localized tumors. Peptide receptor radionuclide therapy (PRRT) is a promising treatment option for patients with metastatic or unresectable pulmonary neuroendocrine tumors. New targeted therapies using angiogenesis inhibitors, mTOR inhibitors, and tyrosine kinase inhibitors are being tested for their effectiveness in many previous studies. Typical carcinoid tumors metastasize less frequently than AC, the 5-year survival rate of patients with TC being over 90%. Patients with AC have a 5-year survival rate between 35% and 87%. The highly malignant LCNEC and SCLC, on the other hand, have a 5-year survival rate between 15% and 57%, and <5% respectively. The increasing number of therapeutic options and diagnostic procedures requires a multidisciplinary approach and decision-making in multidisciplinary tumor conferences to ensure a personalized treatment approach. Therefore patients with a neuroendocrine neoplasm of the lung should be treated in specialized centers.

[Expert dialogue: neuroendocrine tumours of the lungs and gastroenteropancreatic system]. / Expertendialog: Neuroendokrine Tumore der Lunge und des gastroenteropankreatischen Systems.

BACKGROUND: Neuroendocrine tumours of the lung exhibit an increasing incidence and prevalence. However, data on the diagnosis of and therapy for these tumours are sparse compared to neuroendocrine tumours of the gastroenteropancreatic system. METHODS: The present article reflects a dialogue between experts on neuroendocrine tumors of the lung and the gastroenteropancreatic system held on February 25th and 26th in Weimar, Germany. RESULTS: Many similarities exist between neuroendocrine tumours of the lung and the gastroenteropancreatic system but there are also significant differences. Similarities exist mainly concerning pathology, diagnosis and therapy. Differences exist regarding the systemic therapy and the significantly lower incidence of paraneoplastic syndromes. Somatostatin receptor PET/CT with gallium-68 labelled somatostatin analogues and peptide receptor radiotherapy are innovative methods for the diagnosis of and therapy for neuroendocrine tumours of the lung. The first treatment option remains complete resection of the tumour. Small molecules like everolimus (Afinitor®) have been tested in clinical trials and have been shown to prolong progression-free survival. CONCLUSIONS: Additional studies are necessary and efforts should be undertaken to establish a registry to increase data on methods suitable for he diagnosis of and therapy for neuroendocrine tumours of the lung.