Effect of Postoperative Radiotherapy in Thymoma Patients: A SEER-Based Study.

INTRODUCTION: The role of postoperative radiation therapy (PORT) for thymoma is under debate, especially in patients aged ≥60 years with an advanced stage (Masaoka stages III and IV). We aimed to evaluate the efficacy of PORT for thymoma in a population-based registry. METHODS: A retrospective analysis of the Surveillance, Epidemiology, and End Results (SEER) database was conducted to compare the outcomes of thymoma patients with or without PORT. The primary outcomes were overall survival (OS) and cancer-specific survival (CSS). Conditional inference tree analyses were performed for risk classification according to the study variables. Cox regression was performed to evaluate the prognostic effect of PORT in the specific subgroups. RESULTS: A total of 2,236 patients were included. The conditional inference tree analysis identified that an age ≥60, a Masaoka stage ≥3, and the year of diagnosis were important factors when classifying patients into prognostic subgroups. PORT was found to be a protective predictor of OS in patients aged ≥60 years, those with a Masaoka stage III-IV, and those diagnosed after 2005. Further subgroup analyses revealed that PORT was significantly associated with a better OS (HR = 0.77) in patients aged ≥60 years, whereas it was not significantly associated with CSS. CONCLUSIONS: An older age (≥60 years) is critical for predicting survival outcomes in thymoma patients. Moreover, patients aged ≥60 years could benefit from PORT in terms of OS.

Outcomes of surgery for gastric cancer with distant metastases: a retrospective study from the SEER database.

BACKGROUND: The role of surgical therapy in gastric cancer patients with distant metastases remains controversial. This retrospective analysis was performed to identify whether gastric cancer patients with distant metastases might benefit from surgery. PATIENTS AND METHODS: A total of 5185 patients from the SEER database who were initially diagnosed with histologically confirmed gastric cancer with distant metastases from 2004 to 2009 were included. Patients were divided into the following three groups: patients who underwent resection of both the primary tumor and distant metastatic tumors ('PMTR' group), patients who only underwent resection of the primary tumor ('PTR' group) and patients who did not undergo any surgery ('No surgery' group). We employed the Kaplan-Meier analysis, the log-rank test and multivariate Cox proportional hazards regression models to estimate the survival time of the different groups. RESULTS: A total of 5185 patients had a median survival time (MST) of 9.0 months. The improvement in survival of the 'PMTR' and 'PTR' groups was significantly different compared with that of the 'No surgery' group (MST, 12.0 vs 12.0 vs 9.0 months, respectively, P<0.001; 1-year survival rate, 49.6% vs 49.1% vs 30.1%, respectively, P<0.001; 3-year survival rate, 12.5% vs 15.1% vs 5.8%, respectively, P<0.001), whereas no significant difference was found between the 'PMTR' group and 'PTR' group (P=0.642). Multivariate Cox proportional analysis showed that surgery was an independent prognostic factor ('PMTR', hazard ratio (HR) =0.648, 95% confidence interval (CI) 0.574-0.733, P<0.001; 'PTR', HR=0.631, 95% CI 0.583-0.684, P<0.001). CONCLUSIONS: This retrospective analysis demonstrated that combined PTR and metastasectomy or PTR alone were independent prognostic factors for survival improvement in gastric cancer patients with distant metastases. Because no statistically significant difference in survival was observed between the 'PMTR' group and 'PTR' group, PTR, which is a more minor surgery, might be more appropriate than PMTR in clinical practice for gastric cancer patients with distant metastases.

The clinicopathological features and prognostic factors of gastric squamous cell carcinoma.

Primary gastric squamous cell carcinoma (SCC) is an exceedingly rare disease. We increased the understanding of gastric SCC and evaluated prognostic factors of gastric SCC.In this large-population cohort study, we retrospectively collected 163 primary gastric SCC and 66,209 primary gastric adenocarcinoma cases from the surveillance, epidemiology, and end results program (SEER) database from 1988 to 2012. The Chi-squared test demonstrated the distributed differences. Cox proportional hazards regression model was used to evaluate the prognostic factors.Gastric SCC accounted for 0.2% of all the primary gastric cancer cases. The mean age of patients with gastric SCC was 69.6 years old, and the man-to-woman ratio was 2.3:1. The proportion of black was higher in gastric SCC than gastric adenocarcinoma (P < 0.001). Almost half of the gastric SCCs were diagnosed in stage IV and more than half were poorly differentiated. In gastric SCC, the median survival was 8.0 months and the 5-year overall survival (OS) was 32.7%; in gastric adenocarcinoma the median survival rate was 19.0 months and the 5-year OS was 35.4%. The multivariate analysis showed that number of primary lesions, tumor location, grade, and stage were independent prognostic factors in gastric SCC. The tumor stage was the most important prognostic factor.Primary gastric SCC is exceedingly rare. Compared with gastric adenocarcinoma, gastric SCC was more frequent in black patients and was usually diagnosed when it was poorly differentiated and at a later stage. On the whole, gastric SCC has a poorer outcome. Disease stage is likely a key determinant in survival.

Surgical Intervention Improves Survival for Metastatic Non-Small Cell Lung Cancer Patients.

Surgical intervention for stage IV non-small cell lung cancer (NSCLC) is still controversial. This study sought to evaluate the clinical effects of surgical intervention on survival in patients with stage IV NSCLCs and to identify the cohort benefitting the most from surgery.A retrospective study from the Surveillance, Epidemiology, and End Results database was performed to compare the survival of stage IV NSCLC patients who had undergone surgery with those who did not undergo surgery. Overall survival (OS) was evaluated using the Kaplan-Meier method and the log-rank test. The Cox proportional hazards model was used for multivariate analysis.The total number of eligible patients was 43,538, including 16.8% in the M1a stage and 83.2% in the M1b stage. The percentages of patients with no surgery (NONE), only metastatic tumor resection (MTR), only primary tumor resection (PTR), and both primary and metastatic tumor resection (PMTR) were 89.0%, 6.7%, 3.5%, and 0.8%, respectively; the corresponding 5-year survival rates were 2.0%, 4.0%, 13.0%, and 20.0%, respectively (P < 0.001); and the corresponding OS rates were 11.1 months, 14.7 months, 29.4 months, and 34.9 months, respectively (P < 0.001). Notably, the pairwise comparisons of 5-year survival rate and OS among the subgroups were all statistically significant. The multivariate analysis showed that surgical intervention was correlated with longer survival in patients with stage IV NSCLC. The stratified analysis showed significant differences in the OS on strata of the M1a stage and strata of the M1b stage. In the M1a stage, patients with PTR had significantly better OS than those with NONE (P < 0.001) or MTR (P < 0.001) but showed no significant differences compared with those with PMTR (P = 0.174); patients with MTR did not have prolonged survival compared with patients with NONE (P = 0.185), and they also did not have prolonged survival compared with patients with PMTR (P = 0.052). In the M1b stage, pairwise comparisons of OS were all statistically significant among the subgroups (P < 0.001).Surgical intervention can prolong survival to different degrees according to the modalities of surgery in stage IV NSCLC.