RESUMO
Background Gastric cancer is one of the most prevalent cancers in the world and the third most common cause of death from cancer. The diagnosis and treatment are often complex and require a multifaceted approach. Hence, appropriate and timely management is essential for better patient outcomes. Our aim was to determine if rural inhabitation affects the mortality of patients with gastric adenocarcinoma. If such an association exists, we propose to ascertain whether this is related to delayed diagnosis, differing tumor characteristics, or treatment inequalities. Methods The Cox model was applied to gastric adenocarcinoma cases diagnosed during 2004-2011 in American residents aged 20+ years in the Surveillance, Epidemiology, and End Results (SEER) program to determine the impact of rurality on mortality. Binary logistic regression was used to compare the odds of not receiving surgical treatment for localized tumors between rural and urban areas. It was also used to measure the association of rurality with stage at diagnosis (non-metastatic vs. metastatic). Results There was a significant association of rurality on 5-year mortality [HR 1.14 (1.09-1.20), p < 0.01]. No significant association was observed between rural-urban residency and stage at diagnosis, with an odds ratio (OR) of 0.95 (0.87-1.03), p = 0.21. The median time from diagnosis to any first-course treatment was one month for both rural and urban counties. Rural residents were far more likely not to receive surgical treatment for localized tumors than their urban counterparts [OR 1.70 (1.41-2.05), p < 0.01]. A greater percentage of rural inhabitants had cardia tumors as compared to urban ones, 39.8% vs. 33.8% respectively. Non-cardia tumors were far less likely not to receive surgical treatment (i.e., more likely to receive surgical treatment) than cardia tumors [OR 0.35 (0.30-0.41), p < 0.01]. Conclusions Rurality is associated with worse gastric adenocarcinoma mortality. This may be due to a lesser probability of receiving surgical treatment for early-stage disease and differences in the primary site of the tumor between rural and urban counties, but not due to differences in stage at presentation. Future research should focus on improving health care access in rural communities.
RESUMO
Background Appendiceal carcinoma has an insidious clinical presentation, and these tumors are rarely suspected prior to surgery, potentially leading to late diagnosis. The aim of this study is to investigate the prevalence of metastatic disease at initial presentation and potentially associated sociodemographic characteristics. Methods Patients were identified from the Surveillance, Epidemiology, and End Results (SEER) program using the International Classification of Diseases for Oncology-3 (ICD-O-3) histology/behavior codes between 2010 and 2015. Firth logistic regression was performed to determine the association of metastasis at presentation with tumor subtype, adjusted for age, race, sex, insurance and marital status, tumor grade, and tumor and nodal stage using the 7th edition of the American Joint Committee on Cancer (AJCC) staging system. Results We identified a total of 3,447 patients with known metastatic status. A total of 38.4% had metastatic disease at diagnosis. Compared to colonic-type adenocarcinoma (CA), mucinous adenocarcinoma (MA) and signet ring cell carcinoma (SC) were more likely to present with metastasis at diagnosis (OR: 2.34; 95% CI [1.80- 3.06]; OR: 1.93 [1.29-2.89], respectively), however, goblet cell carcinoma (GC) was less likely (OR: 0.59 [0.36-0.93]). Compared to tumors invading the submucosa (T1 stage), tumors invading deeper through the visceral peritoneum or nearby organs (T4 stage) were significantly more likely to present with metastatic disease (OR: 3.46 [2.24-5.51]). Tumors invading the muscularis propria (T2 stage) or deeper into the subserosa, or the mesoappendix (T3 stage) were less likely to present with metastatic disease (OR: 0.34 [0.16-0.71]); OR: 0.55 [0.34-0.91], respectively). Compared to no regional lymph node spread, four or more regional lymph node involvement (N2 stage) was more likely to present with metastatic disease (OR: 2.19 [1.53-3.16]). Men were less likely to present with metastatic disease (OR: 0.60 [0.48-0.73]). A total of 90.1% of CA, 84.2% of GC, 42.2% of MA, and 78.5% of SC patients with metastasis at diagnosis had extraperitoneal distant metastasis (M1b). Conclusions A significant proportion of patients with newly diagnosed appendiceal carcinoma presented with metastatic disease, concerning substantial diagnostic delay and potentiating the need for aggressive treatments. Predictors of metastatic disease included female sex, histologic subtype, and significant regional lymph node involvement. Future research should focus on earlier detection and explore tumor biology.