Answer 1: D (Atypical carcinoid tumor)
Answer 2: D (All of the above)
Comment: Primary pulmonary neuroendocrine tumors represent about 20% of all lung cancers. They are classified into four categories:
1. Typical carcinoid tumor
2. Atypical carcinoid tumor
3. Large-cell neuroendocrine tumor
4. Small-cell neuroendocrine tumor
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 p53 and ras mutations are useful prognostic indicators.
This Image IQ has been provided by the Center for Genomic Pathology
1. Gustafsson BI, Kidd M, Chan A, et al. Bronchopulmonary neuroendocrine tumors. Cancer. 2008 Jul 1;113(1):5-21. PubMed PMID: 18473355.
2. 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 May;148(5):1531-1541. PubMed PMID: 8623922.
3. Kobayashi Y, Tokuchi Y, Hashimoto T, et al. Molecular markers for reinforcement of histological subclassification of neuroendocrine lung tumors. Cancer Sci. 2004 Apr;95(4):334-341. PubMed PMID: 15072592.
4. Rekhtman N. Neuroendocrine tumors of the lung: an update. Arch Pathol Lab Med. 2010 Nov;134(11):1628-38. Review. PubMed PMID: 21043816.