RESUMO
BACKGROUND: Studies demonstrate higher mortality rates from colon cancer in American Indian/Alaskan Native (AI/AN) patients compared to non-Hispanic White (nHW). We aim to identify factors that contribute to survival disparities. METHODS: We used the National Cancer Database to identify AI/AN (n = 2127) and nHW (n = 527,045) patients with stage I-IV colon cancer from 2004 to 2016. Overall survival among stage I-IV colon cancer patients was estimated by Kaplan-Meier analysis; Cox proportional hazard ratios were used to identify independent predictors of survival. RESULTS: AI/AN patients with stage I-III disease had significantly shorter median survival than nHW (73 vs 77 months, respectively; p < 0.001); there were no differences in survival for stage IV. Adjusted analyses demonstrated that AI/AN race was an independent predictor of higher overall mortality compared to nHW (HR 1.19, 95% CI 1.01-1.33, p = 0.002). Importantly, compared to nHW, AI/AN were younger, had more comorbidities, had greater rurality, had more left-sided colon cancers, had higher stage but lower grade tumors, were less frequently treated at an academic facility, were more likely to experience a delay in initiation of chemotherapy, and were less likely to receive adjuvant chemotherapy for stage III disease. We found no differences in sex, receipt of surgery, or adequacy of lymph node dissection. CONCLUSION: We found patient, tumor, and treatment factors that potentially contribute to worse survival rates observed in AI/AN colon cancer patients. Limitations include the heterogeneity of AI/AN patients and the use of overall survival as an endpoint. Additional studies are needed to implement strategies to eliminate disparities.
RESUMO
BACKGROUND: Infection with the human T-cell lymphotropic virus, type 1 (HTLV-1) has been associated with an increased Th1 response. Interestingly, a higher prevalence of helminthic coinfection has been observed among infected individuals, and subsequent modulation of the immune response typically associated with helminths may influence clinical outcomes among HTLV-1 coinfected individuals. OBJECTIVE: This study was conducted to elucidate the association between helminthic coinfection and the development of clinically characterized neurologic disease that occurs in HTLV-1 infection. STUDY DESIGN: In a cohort analysis, incidence of HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP) was recorded. Incidence of clinical outcomes and disease-free survival of several neurologic outcomes associated with HTLV-1 were estimated using the Kaplan-Meier method with log-rank tests. The relationships between helminthic infection and risk of HTLV-1 neurologic outcomes were assessed by Cox proportional hazard modeling. RESULTS: Seventy-four coinfected and 79 non-coinfected patients were followed, with 92 helminthic infections observed in the coinfected group. One patient per group developed HAM/TSP and the risk of progression to neurologic disease outcomes did not differ among those with and without helminthic coinfection (p>0.45). A significant difference was noted in the prevalence of neurologic disease outcomes among all patients at the conclusion of the study (p<0.01). CONCLUSIONS: These data suggest that treated helminthic infection does not affect risk of development of neurologic disease in HTLV-1 infection, and reinforce that treatment of helminths does not adversely affect patients with HTLV-1. Importantly, among all patients, an overall progression of neurologic disease was observed.