The diagnostic utility of the triple markers Napsin A, TTF-1, and PAX8 in differentiating between primary and metastatic lung carcinomas

Abstract

Napsin A and thyroid transcription factor-1 (TTF-1) are useful biomarkers for differentiating lung adenocarcinoma from squamous cell carcinoma and also for differentiating primary lung adenocarcinoma from metastatic lung carcinoma. Pair-boxed 8 (PAX8) can help in distinguishing primary lung carcinoma from metastatic carcinomas and help to determine the primary sites of metastatic carcinomas. Immunohistochemistry for Napsin A, TTF-1, and PAX8 were performed on 193 cases of carcinoma: 50 primary lung carcinoma and 143 carcinomas from other sites. Napsin A and TTF-1 were positive in 54, 52 % of lung carcinomas cases, respectively. While in adenocarcinoma cases, their expressions were 86.7 and 83.3 %, respectively. PAX8 was negative in all lung carcinomas. TTF-1 and PAX8 were positive in 93.3 and 96.7 % of thyroid carcinoma cases and in 87.5 and 93.8 % of papillary carcinoma respectively, and both were positive in 100 % of follicular carcinoma. Napsin A was negative in all thyroid carcinomas. Napsin A and PAX8 were positive in 50 and 93.3 % of renal carcinoma cases and in 81.8 and 100 % of papillary carcinoma, 38.5 and 92.3 % of clear cell carcinoma, and 16.7 and 83.3 % of chromophobe carcinoma respectively. TTF-1 was negative in all renal carcinomas. PAX8 was positive in 80 % of ovarian carcinoma cases; 100 and 60 % of serous mucinous carcinomas, respectively. It was also positive in 100 % of endometrial carcinoma. Napsin A and TTF-1 were negative in both ovarian and endometrial carcinomas. Our data demonstrated that combined use of Napsin A, TTF-1, and PAX8 may help in differentiating between primary lung adenocarcinoma and metastatic lung carcinomas.

Surfactant Protein A and Napsin A in the Immunohistochemical Characterization of Canine Pulmonary Carcinomas: Comparison With Thyroid Transcription Factor-1

“…23,25 Napsin A reactivity in renal tissue has also been documented in humans, with expression in approximately 40% of clear cell renal carcinomas and in more than 80% of papillary renal carcinoma subtypes. 9,43 In dogs, both of these renal tumor subtypes commonly metastasize to the lung. 8 The majority of tumors expressed all 3 markers.…”

Bilateral breast adenocarcinomas with EML4—ALK fusion in a patient with multiple metastases successfully treated with crizotinib: is lung the primary site?

“… 8 As useful markers, Napsin A and TTF-1 are positive in 86.7% and 83.3% of lung adenocarcinomas, respectively. 9 We also note that TTF-1 positivity is rare but does occur in primary breast cancer, being reported in 2.4% of cases. 10 The case reported here was Napsin A-, ER-, PR-, and Her-2 negative but TTF-1 positive.…”

Occult ovarian clear-cell carcinoma diagnosed as primary adenocarcinoma of the lung: A case report of a diagnostic pitfall for clinicians and pathologists

“…Positive staining for PAX8 in the nucleus is a useful IHC marker implying renal, thyroid, or Müllerian carcinoma including ovarian CCC [ 8 ]. By contrast, lung adenocarcinoma should not express PAX8 [ 9 , 10 ]. Although PAX8 may not be usually investigated when tumoral lesions are only identified in the lung and liver, it is important to keep in mind the necessity of PAX8 for excluding carcinoma of Müllerian, renal, or thyroid origin.…”