Intermediate-term oncologic outcomes after video-assisted thoracoscopic thymectomy for early-stage thymoma.

OBJECTIVE: To evaluate the impact on patient survival of video-assisted thoracoscopic surgery (VATS) thymectomy for the treatment of early-stage thymoma, by comparing the intermediate-term oncologic outcomes with outcomes after open thymectomy. METHODS: Eighty-two patients who underwent complete resection of a Masaoka stage I or II thymoma between November 1998 and December 2011 were reviewed. RESULTS: The patients included 32 men and 50 women (median age, 57 years; range, 20-90 years), of whom 44 had stage I thymoma and 38 had stage II thymoma. Seventy-one patients underwent VATS, of whom 4 (5.6%) underwent conversion to open thymectomy; the remaining 11 patients underwent planned open thymectomy. Thirty-six patients underwent total thymectomy and 46 underwent partial thymectomy. Operative mortality was nil. The tumor stage, tumor size, and proportion of patients who underwent total thymectomy were not significantly different between the open and VATS thymectomy groups. The median follow-up period was 49 months (VATS, 48 months; open, 52 months). There was a significant difference between the 2 groups for the estimated 5-year overall survival (VATS, 97.0%; open, 79.5%; P=.041) but not in the estimated 5-year recurrence-free survival. CONCLUSIONS: Our findings indicate that the intermediate-term oncologic outcomes after VATS thymectomy for early-stage thymoma are as favorable as outcomes after open thymectomy. Further follow-up is still required to evaluate the long-term outcomes after VATS thymectomy.

Tumorigenic role of orphan nuclear receptor NR0B1 in lung adenocarcinoma.

Cancer stem cells are a limited population of tumor cells that are thought to reconstitute whole tumors. The Hoechst dye exclusion assay revealed that tumors are composed of both a main population and a side population of cells, which are rich in cancer stem cells. NR0B1 is an orphan nuclear receptor that is expressed to a greater extent in the side population, as compared with the main population, of a lung adenocarcinoma cell line. In this study, we investigated the role of NR0B1 in lung adenocarcinoma cells. Reduction of NR0B1 expression levels in lung adenocarcinoma cell lines resulted in vulnerability to anti-cancer drugs and decreased abilities for invasion, in vitro colony formation, and tumorigenicity in non-obese diabetic/severe compromised immunodeficient mice. When 193 cases of lung adenocarcinoma were immunohistochemically examined, higher levels of NR0B1 expression correlated with higher rates of lymph node metastasis and recurrence. Multivariate analysis revealed high NR0B1 expression levels, stage of the disease, and size of tumor to be independent unfavorable prognostic factors for overall and disease-free survival rates. In clinical samples, NR0B1 expression levels inversely correlated to the proportion of methylated CpG sequences around the transcription initiation site of the NR0B1 gene, suggesting the epigenetic control of NR0B1 transcription in lung adenocarcinoma. In conclusion, NR0B1 might play a role in the malignant potential of lung adenocarcinoma.

Expression of CUB domain containing protein (CDCP1) is correlated with prognosis and survival of patients with adenocarcinoma of lung.

CUB domain containing protein (CDCP1), a transmembrane protein with intracellular tyrosine residues which are phosphorylated upon activation, is supposed to be engaged in proliferative activities and resistance to apoptosis of cancer cells. Expression level of CDCP1 was examined in lung adenocarcinoma, and its clinical implications were evaluated. CDCP1 expression was immunohistochemically examined in lung adenocarcinoma from 200 patients. Staining intensity of cancer cells was categorized as low and high in cases with tumor cells showing no or weak and strong membrane staining, respectively. MIB-1 labeling index was also examined. There were 113 males and 87 females with median age of 63 years. Stage of disease was stage I in 144 cases (72.0%), II in 19 (9.5%), and III in 37 (18.5%). Sixty of 200 cases (30.0%) were categorized as CDCP1-high, and the remaining as CDCP1-low. Significant positive correlation was observed between CDCP1-high expression and relapse rate (P < 0.0001), poor prognosis (P < 0.0001), MIB-1 labeling index (P < 0.0001), and occurrence of lymph node metastasis (P = 0.0086). There was a statistically significant difference in disease-free survival (DFS) (P < 0.0001) and overall survival (OS) rates (P < 0.0001) between patients with CDCP1-high and CDCP1-low tumors. Univariate analysis showed that lymph node status, tumor stage, and CDCP1 expression were significant factors for both OS and DFS. Multivariate analysis revealed that only CDCP1 expression was an independent prognostic factor for both OS and DFS. CDCP1 expression level is a useful marker for prediction of patients with lung adenocarcinoma

Prognostic significance of heat shock protein 105 in lung adenocarcinoma.

Heat shock protein 105 (HSP105) is overexpressed in various tumors and is known to protect cells from cytotoxic stimuli. The prognostic significance of HSP105 expression in cancer has not been fully evaluated. Here, HSP105 expression in lung adenocarcinoma was immunohistochemically examined in 116 patients: 68 males and 48 females with ages ranging from 38-81 (median 63) years. Tumor stage was I in 64, II in 16 and III in 36 patients. In non-cancerous tissues, HSP105 was expressed in the ciliated cells of bronchi. Tumor cells were constantly positive for HSP105, with varying intensities. The HSP105 score in each case was determined based on the staining intensity of the tumor cells occupying the widest area of cancerous tissue as follows: cases with tumor cells showing an intensity weaker than, comparable to and stronger than the bronchial epithelium were assigned a score of 1, 2 and 3, and numbered 84, 19 and 13 cases, respectively. HSP105 score was significantly correlated with the rate of recurrence and the stage of the disease. Univariate analysis showed that lymph node metastasis, disease stage and HSP105 score were unfavorable prognostic factors. Multivariate analysis revealed that lymph node metastasis and HSP105 score were independent prognostic factors for overall and disease-free survival. HSP105 expression is useful for the prediction of prognosis in patients with lung adenocarcinoma.