Browsing by Author "Mao, Rui"

Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Adjuvant Chemotherapy Versus Observation Following Resection for Patients With Nonmetastatic Poorly Differentiated Colorectal Neuroendocrine Carcinomas.
    (Annals of surgery, 2019-08-30) Mao, Rui; Li, Kan; Cai, Jian-Qiang; Luo, Sheng; Turner, Megan; Blazer, Dan; Zhao, Hong
    OBJECTIVE:The aim of this study was to determine whether adjuvant chemotherapy (AC) provides a survival benefit in patients with nonmetastatic poorly differentiated colorectal neuroendocrine carcinomas (CRNECs) following resection. BACKGROUND:There is little evidence to support the association between use of AC and improved overall survival (OS) in patients with CRNECs. METHODS:Patients with resected non-metastatic CRNECs were identified in the National Cancer Database (2004-2014). Inverse probability of treatment weighting (IPTW) method was used to reduce the selection bias. IPTW-adjusted Kaplan-Meier curves and Cox proportional hazards models were used to compare OS of patients in different treatment groups. RESULTS:A total of 806 patients diagnosed between 2004 and 2014 met the study entry criteria. Of these, 394 patients (48.9%) received AC. IPTW-adjusted Kaplan-Meier curves showed that median OS was significantly longer for AC versus observation [57.4 (interquartile range, IQR, 14.8-153.8) vs 38.2 (IQR, 10.4-125.4) months; P = 0.007]. In IPTW-adjusted Cox proportional hazards regression analysis, AC was associated with a significant OS benefit [hazard ratio (HR) = 0.73, 95% confidence interval (CI) 0.64-0.84; P < 0.001]. The results were consistent across subgroups stratified by pathologic T stage, pathologic N stage, and surgical margin status. Subgroup analysis according to tumor location demonstrated improved OS in the adjuvant therapy cohort among patients with left-sided neuroendocrine carcinomas (HR, 0.55; 95% CI, 0.44-0.68), but not in those with right-sided disease (HR, 0.89; 95% CI, 0.74-1.07). CONCLUSIONS:Patients with nonmetastatic CRNECs may derive survival benefit from AC. These findings support current guidelines recommending AC in patients with poorly differentiated neuroendocrine carcinomas in the colon and rectum. Efforts in education and adherence to national guidelines for NECs are needed.
  • Thumbnail Image
    ItemOpen Access
    Outcomes of Lymph Node Dissection for Non-metastatic Pancreatic Neuroendocrine Tumors: A Propensity Score-Weighted Analysis of the National Cancer Database.
    (Annals of surgical oncology, 2019-06-17) Mao, Rui; Zhao, Hong; Li, Kan; Luo, Sheng; Turner, Megan; Cai, Jian-Qiang; Blazer, Dan
    BACKGROUND:Although the National Comprehensive Cancer Network (NCCN) guidelines recommend use of lymph node dissection (LND) in patients with pancreatic neuroendocrine tumors (pNETs) > 2 cm, there is limited evidence to support the association between use of LND and overall survival (OS). METHODS:Patients with resected pNETs were identified in the National Cancer Database (2004-2014). The inverse probability of treatment weighting (IPTW) method was used to reduce the selection bias. IPTW-adjusted Kaplan-Meier curves and Cox proportional hazards models were used to compare OS of patients in different treatment groups. RESULTS:A total of 2664 patients diagnosed met the study entry criteria. Of these, 2132 patients (80.6%) received LND, with a median of nine nodes removed. Positive nodes were identified in 28.0% of patients who underwent LND. IPTW-adjusted Kaplan-Meier analysis showed that median OS was similar between the LND and LND-omitted groups (152.8 vs. 147.3 months; p = 0.61). In IPTW-adjusted Cox proportional hazards regression analysis, LND was not associated with an OS benefit (hazard ratio [HR] 1.15, 95% confidence interval [CI] 0.94-1.42; p = 0.18). The results were consistent across subgroups stratified by clinical T and N stages. Among patients with lymph node metastasis, the number of removed nodes (NRN) above the median was not associated with an improved OS (HR 0.82, 95% CI 0.60-1.13; p = 0.22). CONCLUSIONS:LND had no additional therapeutic benefit among patients undergoing resection for pNETs. The present findings should be considered when managing patients with resectable pNETs.