Role Of Thyroid Transcription Factor 1 Expression In Metastatic Lymph Node Carcinoma Of Pulmonary Adenocarcinoma Origin

Objective:To investigate the value of thyroid transcription factor 1 expression in metastatic lymph node adenocarcinoma in the differential diagnosis of primary pulmonary carcinoma and extra-pulmonary adenocarcinoma except thyroid adenocarcinoma and its prognostic implication.Methods: The immunohistochemical staining for thyroid transcription factor 1,including 43 cases of metastatic lymph node adenocarcinoma of pulmonary adenocarcinoma origin and 43 cases of metastatic lymph node adenocarcinoma of extra-pulmonary origin except thyroid origin , was performed , and the immunohistochemical staining for Ki-67 and p53 proteins in 43 cases of metastatic lymph node adenocarcinoma of pulmonary origin was also peformed,and TTF-1'S relationship with Ki-67 and P53 protein was analyzed,and several clinicopathologic variables were obtained.Results: (1)TTF-1 immunoreactivity was found in 32 (74.4%) in 43 cases of metastatic lymph node adenocarcinoma of pulmonary origin and The 43 cases of metastatic lymph node adenocarcinoma of extra-pulmonary origin except thyroid origin were completely devoid of TTF-1 immunoreactivity (0%).The sensitivity in the differential diagnosis of primary pulmonary adenocarcinoma and extra-pulmonary adenocarcinoma except thyroid carcinoma was 74.4%,specificity 100%,positive predictive value 100%,negative predictive value 79.6%. (2)TTF-1 expression in metastatic lymph node adenocarcinoma of pulmonary origin was not associated with patient's age, general type,quantity of smoke,differentiation and TNM stage,however, TTF-1 expression in metastatic lymph node adenocarcinoma of pulmonary origin in this study was significantly higher in the female than in male(P=0.002).(3)Significant positive correlation was found between TTF-1 expression and Ki-67 protein (R=0.409,P=0.001);And there was also significant positive correlation between TTF-1 expression and P53 protein (R=0.298,P=0.014).Conclusions: TTF-1 expression in metastatic lymph node adenocarcinoma of pulmonary origin play a important role in the differential diagnosis of primary pulmonary adenocarcinoma and extra-pulmonary adenocarcinoma except thyroid carcinoma; TTF-1 expression was significant positive correlation with cell proliferative activity and may be used as bad prognostic marker of pulmonary adenocarcinoma.