Clinical significance of the frequency of regulatory T cells in regional lymph node lymphocytes as a prognostic factor for non-small-cell lung cancer.

BACKGROUND: Regulatory T cells (Tregs) are potent immunosuppressive cells that play a crucial role in tumor immune escape. The purpose of the present study was to evaluate the prognostic significance of the frequency of CD4+CD25+Foxp3+ Tregs in the regional lymph node lymphocytes (RLNL) and peripheral blood lymphocytes (PBL) in patients who underwent surgical resection of non-small cell lung cancer (NSCLC). METHODS: The RLNL and PBL in 158 NSCLC patients who underwent complete surgical resection were collected at the time of surgery. The proportions of CD4+CD25+Foxp3+ cells in the RLNL and PBL were determined by flow cytometry. RESULTS: The average proportions of Tregs in the RLNL and PBL were 1.28% and 0.76%, respectively. The proportion of Tregs in the RLNL was significantly higher than that in the PBL (p < 0.0001). The 5-year overall survival rates of the patients according to the proportion of Tregs in the RLNL were 84.4% and 63.5% in the lower and higher groups, respectively. A significant difference was observed in the survival rate between the higher and lower groups (p = 0.0056). Among the patients with stage I disease, the 5-year survival rate (91.4%) was significantly higher in patients with the lower proportion of Tregs in RLNL that in the higher group (72.1%) (p = 0.0147). CONCLUSIONS: The higher proportion of Tregs in the RLNL was a significant unfavorable prognostic factor, even in patients with node-negative NSCLC. The information about the proportion of Tregs in the RLNL might improve the discriminatory power for assessing the risk of the recurrence of NSCLC.

Clinical significance of expression of cancer/testis antigen and down-regulation of HLA class-I in patients with stage I non-small cell lung cancer.

AIM: The purpose of this study was to investigate the clinical significance of expression of cancer/testis (CT) antigen and down-regulation of HLA class-I in patients with stage I non-small cell lung cancer (NSCLC), which underwent complete surgical resection. PATIENTS AND METHODS: The expression of HLA class-I molecules was evaluated in 136 resected NSCLC specimens by immunohistochemistry. The results were scored as the percentage of stained tumor cells and categorized into two groups: 0-79%, reduced expression; and >80%, normal expression. The expression of CT antigen was performed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The expression of HLA class-I was normal in 49 tumors (36%), and there was reduced expression in 87 tumors (64%). The expression of Melanoma antigen (MAGE)-A3, MAGE-A4, and Kita-Kyushu lung cancer antigen-1 (KK-LC-1) was positive in 34 (25.0%), 22 (16.2%), and 42 (30.9%) patients, respectively. There was no significant difference in the proportion of HLA class-I expression associated with the expression of any of the CT antigens. Among the patients with positive expression of at least one of the CT antigens, the 5-year survival rate of the patients with the normal expression of HLA class-I was 87.5%; however, it was 63.4% in patients with the reduced expression of HLA class-I (p=0.0477). CONCLUSION: Reduced expression of HLA class-I was an unfavorable prognostic factor in patients with positive expression of CT antigen, and represents an important hurdle to antigen-based cancer immunotherapy.

Preoperative CYFRA 21-1 and CEA as prognostic factors in patients with stage I non-small cell lung cancer.

PURPOSE: This study investigated the preoperative serum levels of CYFRA 21-1 and CEA as prognostic factors in patients with stage I non-small cell lung cancer. SUBJECTS: This study evaluated 341 patients who had undergone a complete resection for stage I NSCLC between 2002 and 2008. RESULTS: The patients included 193 males and 148 females. The mean age of the patients was 69.2 years (range: 19-88). The histological types included 264 adenocarcinomas, 56 squamous cell carcinomas, 11 large cell carcinomas, and 10 other types of carcinoma. A pneumonectomy was performed in 2 patients, a bilobectomy in 7, a lobectomy in 255, a segmentectomy in 46, and partial resection of the lung in 31 patients. The positive rates for CYFRA 21-1 in the adenocarcinoma and squamous cell carcinoma patients were 33.3% and 76.8%, respectively. The positive rates for CEA in adenocarcinoma and squamous cell carcinoma patients were 23.8% and 26.8%, respectively. The 5-year survival rate after surgery in the normal CYFRA 21-1 group and the high CYFRA 21-1 groups were 92.8% and 75.4%, respectively, in the patients with stage I NSCLC. There was a significant difference between the 2 groups (p<0.0001). The 5-year survival rate according to the serum level of CEA in the patients with stage I NSCLC were 88.3% for the normal group and 76.3% for the high group. In a multivariate analysis using the variables found to be significant prognostic factors in univariate analysis, a high CYFRA 21-1 level was found to be a significant independent prognostic factor (95% confidence interval 1.213-5.442, p=0.014). CONCLUSION: A high preoperative CYFRA 21-1 level was a significant independent prognostic factor in patients with stage I NSCLC. The patients with a high CYFRA 21-1 level should carefully followed-up to rule out occult metastasis. Further clinical studies will be necessary to evaluate the efficacy of adjuvant therapy for the patients selected according to this criterion.