Unusual expression of thyroid transcription factor 1 and napsin A in metastatic adenoid cystic carcinoma of extrapulmonary origin in the lung.

Abstract

OBJECTIVES:

Our study examines thyroid transcription factor 1 (TTF-1) expression in 40 primary adenoid cystic carcinomas (ACCs) arising in various sites and compares TTF-1 expression between primary and metastatic ACCs in 12 cases with distant metastases.

METHODS:

Forty patients with ACCs, including 12 pairs of primary and metastatic ACCs, were evaluated for the immunohistochemical expression of TTF-1 (clone SPT24). In addition, 10 metastatic ACCs to the lung were tested on napsin A and a different TTF-1 antibody (clone 8G7G3) for further evaluation.

RESULTS:

No primary ACCs showed TTF-1 immunoreactivity (clone SPT24). TTF-1 was positive in five (41.7%) of 12 metastatic ACCs; all five cases were found only in the lung and comprised five (50.0%) of 10 cases. In all positive cases, staining was focal and detected only in the cribriform histologic subtype. Staining patterns using both antibodies (both SPT24 and 8G7G3) were very similar, and TTF-1-positive tumor cells were also positive for napsin A. Extrapulmonary ACCs were all negative for TTF-1 regardless of origination and metastasis.

CONCLUSIONS:

TTF-1- and napsin A-positive ACCs in the lung should not be considered primary ACCs because TTF-1 and napsin A can be expressed in metastatic ACCs of the lung.

• Authors: Jungsuk An, Sanghui Park, Sun Hee Sung, Min-Sun Cho, Seung Cheol Kim
• Journal: American journal of clinical pathology (Am J Clin Pathol) Vol. 141 Issue 5 Pg. 712-7 (May 2014) ISSN: 1943-7722 [Electronic] England
• PMID: 24713744 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers, Tumor
• NKX2-1 protein, human
• Nuclear Proteins
• Thyroid Nuclear Factor 1
• Transcription Factors
• Aspartic Acid Endopeptidases
• NAPSA protein, human

Topics

• Adult
• Aged
• Aspartic Acid Endopeptidases (metabolism)
• Biomarkers, Tumor (metabolism)
• Carcinoma, Adenoid Cystic (metabolism, pathology)
• Female
• Humans
• Lung Neoplasms (metabolism, pathology, secondary)
• Male
• Middle Aged
• Nuclear Proteins (metabolism)
• Thyroid Nuclear Factor 1
• Transcription Factors (metabolism)
• Young Adult