Treatment and outcomes of gastric cancer among United States-born and foreign-born Asians and Pacific Islanders

Disaggregating Data on Pacific Islander Gastric Cancer Patients Reveals Survival Disparity

PURPOSE

The incidence and prognosis of Pacific Islanders with gastric cancer is not well documented as previous studies have often aggregated this population with Asians. The purpose of our study was to describe patient and tumor characteristics, as well as prognostic factors of Pacific Islanders with gastric cancer.

METHODS

Patients diagnosed with gastroesophageal junction or gastric adenocarcinoma between 2000 and 2014 were identified in the tumor registry of the largest hospital in Hawaii. Overall survival of Asians, Whites, and Pacific Islanders were calculated using the Kaplan-Meier method and log-rank test. Cox proportional hazards regression models were constructed to assess predictors of survival adjusting for clinical and pathological factors.

RESULTS

A total of 615 patients were included in the final analysis. Pacific Islanders were found to present at a younger age, were more often uninsured or had Medicaid insurance, and were diagnosed with a higher stage of cancer compared to their Asian and White counterparts. Pacific Islanders were less likely to undergo surgery even after adjusting for stage. Race was a prognostic factor and survival was lowest among Pacific Islanders, but only if the model was unadjusted for treatment.

CONCLUSIONS

We present an analysis of the largest cohort of Pacific Islander gastric cancer patients. Pacific Islanders have different sociodemographic characteristics and inferior survival compared to Asian patients and should be independently studied.

The Asian Immigrant Cancer Survivor Experience in the United States: A Scoping Review of the Literature

BACKGROUND

Cancer is the leading cause of death for Asian Americans, a growing population in the United States. While cancer survivors often experience complex issues after diagnosis, being an immigrant and having cancer pose additional challenges.

OBJECTIVE

This scoping review analyzed research about immigrant cancer survivors of Asian ethnicity in the United States and provided a structured method to understand an area of research and evidence. Aims focused on immigrants' experiences and how findings could tailor evidence-based interventions, programs, and resources.

METHODS

The PubMed, CINAHL, and Scopus databases were searched to identify studies in English (2009-2018) targeting Asian immigrant cancer survivors in the United States. While 385 records were initially identified, 32 studies met the inclusion criteria.

RESULTS

Thematic analysis of charted study elements revealed 4 themes with subthemes: (1) survival patterns, (2) barriers, (3) culturally informed care, and (4) quality of life (QOL). While qualitative studies provided insight about the cancer experience from immigrants' perspectives, quantitative designs posed descriptions and associations among QOL concepts.

CONCLUSIONS

Study results illustrate the need for survival research that explores outcomes by Asian ethnic subgroups and tracks the influence of acculturation. Future research should test culturally informed interventions that minimize barriers and foster QOL across the cancer continuum. Culturally tailored instruments can expedite larger-scaled studies that allow generalization.

IMPLICATIONS FOR PRACTICE

Asian immigrants comprise an underserved, vulnerable, and growing group with various cancers. Nurses who care for immigrants and their families should be cognizant of cultural beliefs, values, practices, and issues related to communication, care access, and socioeconomics.

Socio-Demographic Disparities in Gastric Adenocarcinoma: A Population-Based Study

Background: Gastric cancer is one of the leading causes of cancer-related mortality worldwide, accounting for 8.2% of cancer-related deaths. The purpose of this study was to investigate the geographic and sociodemographic disparities in gastric adenocarcinoma patients.

METHODS

We conducted a retrospective study in gastric adenocarcinoma patients between 2004 and 2013. Data were obtained from the National Cancer Data Base (NCDB). Univariate and multivariable analyses were performed to evaluate overall survival (OS). Socio-demographic factors, including the location of residence [metro area (MA) or rural area (RA)], gender, race, insurance status, and marital status, were analyzed.

RESULTS

A total of 88,246 [RA, N = 12,365; MA, N = 75,881] patients were included. Univariate and multivariable analysis showed that RA had worse OS (univariate HR = 1.08, p < 0.01; multivariate HR = 1.04; p < 0.01) compared to MA. When comparing different racial backgrounds, Native American and African American populations had poorer OS when compared to the white population; however, Asian patients had a better OS (multivariable HR = 0.68, p < 0.01). From a quality of care standpoint, MA patients had fewer median days to surgery (28 vs. 33; p < 0.01) with fewer positive margins (6.3% vs. 6.9%; p < 0.01) when compared to RA patients. When comparing the extent of lymph node dissection, 19.6% of MA patients underwent an extensive dissection (more than or equal to 15 lymph nodes) in comparison to 18.7% patients in RA (p = 0.03).

DISCUSSION

This study identifies socio-demographic disparities in gastric adenocarcinoma. Future health policy initiatives should focus on equitable allocation of resources to improve the outcomes.

Nature versus nurture: the impact of nativity and site of treatment on survival for gastric cancer

BACKGROUND

The prognosis of gastric cancer patients is better in Asia than in the West. Genetic, environmental, and treatment factors have all been implicated. We sought to explore the extent to which the place of birth and the place of treatment influences survival outcomes in Korean and US patients with localized gastric cancer.

METHODS

Patients with localized gastric adenocarcinoma undergoing potentially curative gastrectomy from 1989 to 2010 were identified from the SEER registry and two single institution databases from the US and Korea. Patients were categorized into three groups: Koreans born/treated in Korea (KK), Koreans born in Korea/treated in the US (KUS), and White Americans born/treated in the US (W), and disease-specific survival rates compared.

RESULTS

We identified 16,622 patients: 3,984 (24.0%) KK, 1,046 (6.3%) KUS, and 11,592 (69.7%) W patients. KK patients had longer unadjusted median (not reached) and 5-year disease-specific survival (81.6%) rates than KUS (87 months, 55.9%) and W (35 months, 39.2%; p < 0.001 for all comparisons) patients. This finding persisted on subset analyses of patients with stage IA tumors, without cardia/GEJ tumors, with > 15 examined lymph nodes, and treated at a US center of excellence. On multivariable analysis, KUS (HR 2.80, p < 0.001) and W (HR 5.79, p < 0.001) patients had an increased risk of mortality compared to KK patients.

CONCLUSIONS

Both the place of birth and the place of treatment significantly contribute to the improved prognosis of patients with gastric cancer in Korea relative to those in the US, implicating both nature and nurture in this phenomenon.

Toward a Positive Psychology of Immigrants

The vast majority of immigration-focused research in psychology is rooted in deficit models that center on negative health outcomes (e.g., depression, acculturative stress, anxiety, substance use), resulting in a widely held assumption that immigrants are at greater risk for pathology and poor well-being compared with native-born individuals. Moreover, current political discourse often portrays immigrants as more prone to crime compared with native-born individuals. From a positive-psychology perspective, we argue that, despite numerous migration-related challenges, many immigrant populations report positive patterns of psychological health. We also provide evidence that immigrants are, in fact, less prone to crime than their native-born counterparts. We conclude by discussing several contributing factors that account for positive immigrant well-being across the range of destination countries. Ultimately, the field should address questions regarding (a) immigrants’ strategies for coping with the challenges involved in adapting to new homelands and (b) asset-based factors that help immigrants to thrive during difficult life challenges.

Can a gastric cancer risk survey identify high-risk patients for endoscopic screening? A pilot study

BACKGROUND

A questionnaire that distinguishes how variability in gastric cancer prevalence is associated with ethnicity/birth country/immigration/cultural diet along with known risk factors may improve targeting populations for gastric cancer screening in the United States.

METHODS

Existing literature was used to identify the item pool. Cluster analysis, focus groups, and cognitive interviewing were used to reduce collinear items and refine the questionnaire. Logistic regression analysis was used to determine which items distinguished gastric cancer cases from the primary care and community controls.

RESULTS

The results of analysis of data from 40 cases and 100 controls (primary care = 47; community = 53) were used to reduce the 227 item pool to 12 items. After ranking these variables using model bootstrapping, a logistic regression model using the highest ranked eight variables was chosen as the final model. Older age, foreign nativity, daily consumption of cultural food at ages 15-18, less than high-school education, and greater acculturation were significantly associated with being a gastric cancer case compared with the controls.

CONCLUSIONS

An eight-item survey that addresses gastric cancer risk factors, ethnicity, cultural habits, and immigration patterns has potential to identify high-risk persons from multicultural areas within the US, who might benefit from endoscopic screening for gastric cancer.

Selective survival advantage associated with primary tumor resection for metastatic gastric cancer in a Western population

BACKGROUND

The prognosis of metastatic gastric cancer (GC) remains dismal, with a median survival of 10 months. Historically, primary tumor resection was not thought to confer any survival benefit. Although high-level data exist guiding treatment of metastatic GC for patients in the East, no such data exist for Western patients despite inherent ethnic differences in GC biology.

METHODS

The 2006-2012 National Cancer Database was queried for adult patients with metastatic gastric adenocarcinoma. Patients were classified into those who underwent primary tumor resection and chemotherapy (PTRaC) and those who received chemotherapy only. Groups were propensity score matched, and survival was compared using advanced statistical modeling.

RESULTS

A total of 7026 patients met the inclusion criteria: 6129 (87%) patients were treated with chemotherapy alone and 897 (13%) patients were treated with PTRaC. After multivariable adjustment, patients who underwent PTRaC had a significantly better overall survival (OS) than patients who received systemic therapy only (HR, 0.60; 95% CI, 0.56-0.64; p < 0.001). Following full bipartite propensity score-adjusted analysis, 2-year OS for patients who received chemotherapy only was 12.6% (95% CI, 11.7-13.5%), whereas it was 34.2% (95% CI, 31.3-37.5%) for patients who underwent PTRaC (HR for resection: 0.52; 95% CI, 0.47-0.57; p < 0.001).

CONCLUSION

Our data suggest that there exists a subset of patients with metastatic GC for which PTRaC may improve OS. As significant uncertainty still remains, our results support the need for further prospective trials investigating the influence of palliative gastrectomy on survival among Western patients.

Molecular classification of gastric cancer

INTRODUCTION

Gastric cancer is among the most common cancers worldwide. Despite declining incidences, the prognosis remains dismal in Western countries and is better in Asian countries with national cancer screening programs. Complete endoscopic or surgical resection of the primary tumor with or without lymphadenectomy offers the only chance of cure in the early stage of the disease. Survival of more locally advanced gastric cancers was improved by the introduction of perioperative, adjuvant and palliative chemotherapy. However, the identification and usage of novel predictive and diagnostic targets is urgently needed. Areas covered: Recent comprehensive molecular profiling of gastric cancer proposed four molecular subtypes, i.e. Epstein-Barr virus-associated, microsatellite instable, chromosomal instable and genomically stable carcinomas. The new molecular classification will spur clinical trials exploring novel targeted therapeutics. This review summarizes recent advancements of the molecular classification, and based on that, putative pitfalls for the development of tissue-based companion diagnostics, i.e. prevalence of actionable targets and therapeutic efficacy, tumor heterogeneity and tumor evolution, impact of ethnicity on gastric cancer biology, and standards of care in the East and West. Expert commentary: The overall low prevalence of actionable targets and tumor heterogeneity are the two main obstacles of precision medicine for gastric cancer.

Overall Survival Is Impacted by Birthplace and Not Extent of Surgery in Asian Americans with Resectable Gastric Cancer

Survival from gastric cancer in the USA still lags behind Asia. Genetic, environmental, and tumor biology differences, along with extent of surgery have been implicated. Our aim was to evaluate survival outcomes in Asian-American gastric cancer patients undergoing surgical resection by comparing place of birth and clinicopathologic characteristics (including evaluation of 15 lymph nodes).The Surveillance, Epidemiology, and End Results database was queried to identify patients treated surgically for gastric cancer with curative intent in the USA (2000-2010). US-born versus foreign-born Asian-American patients were analyzed for survival. Secondary comparison was made to non-Asian patients. Stage IV and non-surgical patients were excluded. Of 10,089 patients identified, 1467 patients were Asian: 271 were born in the USA, and 1196 were born outside the USA. Median survival was 32 months for non-Asians and 29 months for US-born Asians versus 61 months for Asian immigrants (p < 0.001). On multivariable analysis of overall survival in Asian patients, only US birthplace, older age, and higher stage yielded a significantly poorer outcome. Asian-American patients have a worse prognosis if born in the USA. Anatomic and surgical differences do not explain this disparity; environmental factors may be responsible.

Asian gastric cancer patients show superior survival: the experiences of a single Australian center

BACKGROUND

Survival after curative gastrectomy for gastric cancer varies depending on region. The 5-year survival rates in Western trials reach 36-47% compared with 40-60% in Japanese studies. We analyzed the outcomes of Asian and non-Asian patients at a single Australian institution.

METHODS

We analyzed a prospectively kept database of patients following gastric resection between 1994 and 2010 at a tertiary Australian hospital. Overall survival was the primary endpoint.

RESULTS

A total of 160 patients underwent a R0 gastrectomy with curative intent, of whom 26 (16%) were of Asian descent. Asian patients had a significantly younger age at diagnosis (60 ± 16 vs. 70 ± 11, p < 0.05) and longer overall survival (log-rank p = 0.018). Poor prognostic factors common to both groups included increased tumor length, higher T-score, higher LN ratio, poor tumor differentiation, and the presence of perineural or perivascular invasion. Multivariate analysis showed that non-Asian patients, higher T-score, higher N-score, and perivascular involvement were all independent predictors of poorer outcome.

CONCLUSIONS

This study shows superior overall survival in Asian patients despite similar clinicopathological and treatment data. The younger age at diagnosis in Asian patients may suggest a different disease process between ethnicities. Targeted therapies based on population-specific tumor biology may potentially be beneficial.

Race Influences Stage-specific Survival in Gastric Cancer

Gastric adenocarcinoma studies show improved survival for Asians but have not reported stage-specific overall survival (OS) or disease-specific survival (DSS) by race. The Surveillance, Epidemiology and End Results database was queried for cases of gastric adenocarcinoma between 1998 and 2008. We evaluated OS and DSS by race and stage. Number of assessed lymph nodes was compared among surgical patients. Of 49,058 patients with complete staging data, 35,300 were white, 7709 were Asian, and 6049 were black. Asians had significantly better OS for all stages ( P < 0.001) and significantly better DSS for Stages I ( P < 0.0001) and II ( P = 0.0006). As compared with blacks, whites had significantly better DSS for Stages I ( P < 0.0001), II ( P = 0.0055), III ( P = 0.0165), and IV ( P < 0.0001). Among the 28,133 (57%) surgical patients, average number of evaluated lymph nodes was highest for Asians ( P < 0.0001). Among surgical patients with 15 or more nodes evaluated, DSS was worse in blacks with Stage I disease ( P < 0.05). Blacks with gastric adenocarcinoma have a worse DSS, which disappears when surgical treatment includes adequate lymphadenectomy. Race-associated survival differences for gastric adenocarcinoma might simply reflect variations in surgical staging techniques and socioeconomic factors.

Validating the prognostic and discriminating value of the TNM-classification for gastric cancer - a critical appraisal

AIM

We investigated the effect of the new tumour-, node-, metastasis- (TNM) classification on predicting and discriminating gastric cancer patient prognosis using the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program.

PATIENTS AND METHODS

From the SEER-database we retrieved gastric cancer patients with a primary adenocarcinoma, of Caucasian or Asian ethnicity and without distant metastases (M0). The pTNM-stage was determined according to the 7th edition of the union internationale contre le cancer (UICC) guidelines.

RESULTS

Spanning the period 2004-2010, 6136 patients fulfilled all inclusion criteria including 3424 (55.8%) men, 2712 (44.2%) women, 4629 (75.4%) Caucasian and 1507 (24.6%) Asian patients. 1524 (24.8%) patients underwent total gastrectomy and 4612 (75.2%) non-total gastrectomy. Only in 41.2% of the patients were >15 lymph nodes resected. 1857 (31.0%) patients received radiotherapy. Patient survival depended on ethnicity, type of surgery and radiotherapy. The discriminating value of the UICC-stage grouping could not be validated for Caucasian patients with >15 lymph nodes resected and who had not received radiotherapy: stage groups IIB, IIIA, IIIB and IIIC showed substantial overlap in survival ranges. In addition, the tumour specific survival of the different T-/N-combinations was significantly different in stage groups IIIB and IIIC, respectively.

CONCLUSIONS

Our retrospective analysis of the SEER-database does not validate the discriminating value of stage grouping of the 7th edition of the UICC-stage grouping. A revision should be considered and more reliable prognostic biomarkers are urgently needed.

Conducting high-value secondary dataset analysis: an introductory guide and resources

Secondary analyses of large datasets provide a mechanism for researchers to address high impact questions that would otherwise be prohibitively expensive and time-consuming to study. This paper presents a guide to assist investigators interested in conducting secondary data analysis, including advice on the process of successful secondary data analysis as well as a brief summary of high-value datasets and online resources for researchers, including the SGIM dataset compendium ( www.sgim.org/go/datasets ). The same basic research principles that apply to primary data analysis apply to secondary data analysis, including the development of a clear and clinically relevant research question, study sample, appropriate measures, and a thoughtful analytic approach. A real-world case description illustrates key steps: (1) define your research topic and question; (2) select a dataset; (3) get to know your dataset; and (4) structure your analysis and presentation of findings in a way that is clinically meaningful. Secondary dataset analysis is a well-established methodology. Secondary analysis is particularly valuable for junior investigators, who have limited time and resources to demonstrate expertise and productivity.

The prognostic effect of ethnicity for gastric and esophageal cancer: the population-based experience in British Columbia, Canada

Background

Gastric and esophageal cancers are among the most lethal human malignancies. Their epidemiology is geographically diverse. This study compares the survival of gastric and esophageal cancer patients among several ethnic groups including Chinese, South Asians, Iranians and Others in British Columbia (BC), Canada.

Methods

Data were obtained from the population-based BC Cancer Registry for patients diagnosed with invasive esophageal and gastric cancer between 1984 and 2006. The ethnicity of patients was estimated according to their names and categorized as Chinese, South Asian, Iranian or Other. Cox proportional hazards regression analysis was used to estimate the effect of ethnicity adjusted for patient sex and age, disease histology, tumor location, disease stage and treatment.

Results

The survival of gastric cancer patients was significantly different among ethnic groups. Chinese patients showed better survival compared to others in univariate and multivariate analysis. The survival of esophageal cancer patients was significantly different among ethnic groups when the data was analyzed by a univariate test (p = 0.029), but not in the Cox multivariate model adjusted for other patient and prognostic factors.

Conclusions

Ethnicity may represent underlying genetic factors. Such factors could influence host-tumor interactions by altering the tumor's etiology and therefore its chance of spreading. Alternatively, genetic factors may determine response to treatments. Finally, ethnicity may represent non-genetic factors that affect survival. Differences in survival by ethnicity support the importance of ethnicity as a prognostic factor, and may provide clues for the future identification of genetic or lifestyle factors that underlie these observations.

A prognostic model in patients who receive chemotherapy for metastatic or recurrent gastric cancer: validation and comparison with previous models

PURPOSE

To make up for the limitations of previous prognostic models, we developed and validated a model in patients with metastatic or recurrent gastric adenocarcinoma (AGC), and to compare with previous models.

METHODS

A total of 2,805 patients received chemotherapy for AGC in Asan Medical Center between January 2000 and December 2008 and were randomly split into training and validation sets of 1,870 and 935 patients, respectively. A prognostic model was developed from the training set.

RESULTS

The median follow-up duration was 26.5 months (range, 10.8-116.3), during which time 2,495 patients (88.9%) died. Eight factors associated with poor prognosis were identified by multivariate analysis: ECOG performance status ≥2 (2 points), no gastrectomy, peritoneal metastasis, bone metastasis (2 points), lung metastasis, alkaline phosphatase > 120 IU/l, albumin < 3.3 g/dL, and total bilirubin > 1.2 mg/dL. A prognostic model was developed by dividing patients into good (0-1 points), moderate (2-3), and poor (≥4) risk groups. The overall survival (OS) curves for three risk groups differed significantly for both the training and the validation sets (P < 0.001 each). In the training set, the median OS for the three risk groups was 14.0, 9.4, and 5.1 months, respectively. Application of three previous prognostic models to our validation set showed that the four models, including ours, had similar ability to predict survival outcomes (c-statistics, 0.5520-0.5836).

CONCLUSION

Validation and comparison of prognostic models indicated that our model was as effective as the previous models to stratify the patients with AGC.

Quality of cancer care among foreign-born and US-born patients with lung or colorectal cancer

BACKGROUND

Disparities in care have been documented for foreign-born cancer patients in the United States. However, few data are available regarding patients with lung and colorectal cancer. In the current study, the authors assessed whether patient-reported quality and receipt of recommended care differed between US-born and foreign-born cancer patients.

METHODS

The authors collected surveys and medical records for a population-based cohort including white, Hispanic, and Asian adults (2205 US-born and 890 foreign-born individuals) with lung or colorectal cancer diagnosed in California from 2003 through 2005. Logistic regression was used to assess the association between nativity and patient-reported quality of care and receipt of recommended treatments (adjuvant chemotherapy for stage III colon cancer, adjuvant chemotherapy and radiotherapy for stage II/III rectal cancer, and curative surgery for stage I/II nonsmall cell lung cancer). The authors also assessed whether language explained any differences in care by nativity.

RESULTS

Overall, 46% of patients reported excellent care, but foreign-born patients were less likely than US-born patients to report excellent quality of care (adjusted odds ratio [AOR], 0.80; 95% confidence interval [95% CI], 0.65-1.00), a difference partly explained by the language of the survey, an indicator of English proficiency. Rates of recommended therapies ranged from 64% to 85%; foreign-born patients were less likely to receive chemotherapy and radiotherapy for stage II/III rectal cancer (AOR, 0.35; 95% CI, 0.12-0.99). Rates of other treatments did not differ significantly by nativity.

CONCLUSIONS

Foreign-born cancer patients reported lower quality of care and were less likely to receive some cancer therapies than patients born in the Unites States. Better coordination of care and communication regarding cancer treatments and expanded use of interpreters may lessen these disparities.