AIMS: The histopathological features of some thymic neoplasms overlap with those of pulmonary squamous and large-cell undifferentiated carcinomas, and identification of the primary site may be difficult on routine staining. We have assessed a panel of antibodies that may help to distinguish between neoplasms from these two sites. METHODS AND RESULTS: Antibodies identifying cytokeratin 7 (CK7), CD5, CD10, CD1a and thyroid transcription factor-1 (TTF-1) were applied to a series of 20 thymic neoplasms (thymic carcinomas, atypical thymomas and thymomas), 10 primary squamous cell carcinomas of the lung and 10 large-cell undifferentiated carcinomas of the lung. Staining for TTF-1 was positive in 3/10 large-cell undifferentiated carcinomas, but negative in all other tumours. CD5 showed strong membranous staining in 3/6 thymic carcinomas and 1/14 thymomas, but only focal staining in 1/20 pulmonary carcinomas. CD1a was consistently positive in thymic lymphocytes in both typical and atypical thymomas, but only focally in 1/6 thymic carcinomas. CD1a stained dendritic cells in 7/20 pulmonary carcinomas, but did not stain lymphocytes. Staining for CK7 and CD10 did not aid in differentiating between a pulmonary or thymic origin of the tumour. CONCLUSION: Staining for TTF-1, CD5 and CD1a have potential use in distinguishing between pulmonary and thymic neoplasms.
AIMS: The histopathological features of some thymic neoplasms overlap with those of pulmonary squamous and large-cell undifferentiated carcinomas, and identification of the primary site may be difficult on routine staining. We have assessed a panel of antibodies that may help to distinguish between neoplasms from these two sites. METHODS AND RESULTS: Antibodies identifying cytokeratin 7 (CK7), CD5, CD10, CD1a and thyroid transcription factor-1 (TTF-1) were applied to a series of 20 thymic neoplasms (thymic carcinomas, atypical thymomas and thymomas), 10 primary squamous cell carcinomas of the lung and 10 large-cell undifferentiated carcinomas of the lung. Staining for TTF-1 was positive in 3/10 large-cell undifferentiated carcinomas, but negative in all other tumours. CD5 showed strong membranous staining in 3/6 thymic carcinomas and 1/14 thymomas, but only focal staining in 1/20 pulmonary carcinomas. CD1a was consistently positive in thymic lymphocytes in both typical and atypical thymomas, but only focally in 1/6 thymic carcinomas. CD1a stained dendritic cells in 7/20 pulmonary carcinomas, but did not stain lymphocytes. Staining for CK7 and CD10 did not aid in differentiating between a pulmonary or thymic origin of the tumour. CONCLUSION: Staining for TTF-1, CD5 and CD1a have potential use in distinguishing between pulmonary and thymic neoplasms.
Authors: M E Callister; A Burke-Gaffney; G J Quinlan; A G Nicholson; R Florio; H Nakamura; J Yodoi; T W Evans Journal: Thorax Date: 2006-04-06 Impact factor: 9.139
Authors: Mark Kriegsmann; Thomas Muley; Alexander Harms; Luca Tavernar; Torsten Goldmann; Hendrik Dienemann; Esther Herpel; Arne Warth Journal: Diagn Pathol Date: 2015-12-08 Impact factor: 2.644