A 50-year-old male complains of episodic flushing and tachycardia over the past few months. X-rays revealed a pulmonary mass. Shown is an H&E from the lung. 

Click here for the comparative pathology.

Primary pulmonary neuroendocrine tumors represent about 20% of all lung cancers. They are classified into four categories:

The atypical carcinoids, such as the current example, have been the most difficult to classify. The presence of Chromogranin A or Synaptophysin identifies the tumor as neuroendocrine. Current recommendations suggest that mitotic rate (Ki-67) and 

 mutations are useful prognostic indicators.

 Gustafsson BI, Kidd M, Chan A, et al. Bronchopulmonary neuroendocrine tumors. Cancer. 2008;113:5-21. PubMed PMID: 

 Przygodzki RM, Finkelstein SD, Langer JC, et al. Analysis of p53, K-ras-2, and C-raf-1 in pulmonary neuroendocrine tumors. Correlation with histological subtype and clinical outcome. Am J Pathol. 1996;148:1531-1541. PubMed PMID: 

 Kobayashi Y, Tokuchi Y, Hashimoto T, et al. Molecular markers for reinforcement of histological subclassification of neuroendocrine lung tumors. Cancer Sci. 2004;95:334-341. PubMed PMID: 

 Rekhtman N. Neuroendocrine tumors of the lung: an update. Arch Pathol Lab Med. 2010;134:1628-1638. Review. PubMed PMID: 

Pulmonary Mass in 50-Year-Old Male

Pulmonary Mass in 50-Year-Old Male