E-Newsletter - August 2018

disparities corner

The Alliance Health Disparities Committee, led by Electra D. Paskett, PhD, periodically reviews inclusion of patients involved in Alliance trials to improve best practices for outreach. In upcoming e-newsletters, the committee will share these so Alliance members can benefit from some of the great activities going on throughout our Group and incorporate those that best fit the populations we serve.

In this column, Haejin In, MD, MBA, MPH, FACS, shares the outcomes of a pilot study she conducted on cancer disparities in gastric cancer.

Identifying Gastric Cancer Risk Through Cancer Disparities

IDENTIFYING GASTRIC CANCER RISK THROUGH CANCER DISPARITIES

By Haejin In, MD, MBA, MPH, FACS
Surgical Oncologist, Department of Surgery, Montefiore Medical Center
Assistant Professor of Surgery and Assistant Professor of Epidemiology and Population Health, Albert Einstein College of Medicine

Gastric cancer is highly lethal in the United States with overall five-year survival of only 31 percent. In high prevalence countries, population-wide screening for gastric cancer among middle aged and older adults has resulted in 30 to 60 percent decrease in gastric cancer mortality. Yet, population-wide gastric cancer screening is not feasible in the U.S. due to low incidence in the general population. However, gastric cancer disproportionately affects lower-socioeconomic status ethnic minority groups.

U.S.-born blacks have nearly double the incidence of whites.1-3 Gastric cancer is a top five cancer for certain ethnic groups in the U.S. such as Koreans, Chinese, Japanese, Laotian and Vietnamese,4 as well as for Native Hawaiians and other Pacific Islanders.5 Being from lower socioeconomic status , such as having lower income, lower education and less skilled occupations are also known risk factors.6 Bringing these risk factors together to stratify a person’s risk has the potential to be used for the identification of individuals who should undergo targeted gastric cancer screening. Given that gastric cancer disproportionately affects ethnic minority populations, such a targeted gastric cancer screening program would have great potential to reduce ethnic and SES related disparity for gastric cancer.

As one of the recipients of the 2015 Alliance Cancer Control Program Junior Faculty Award, I proposed a pilot study to investigate this possibility. The study was entitled "Development of a Gastric Cancer Brief Screener to Identify Persons for Screening Endoscopy Referral." Under the mentorship of Bruce Rapkin, PhD, it was conducted in three phases. First, a systematic review was performed to identify gastric cancer risk factors that were used to develop an exhaustive item pool from 16 existing survey instruments. Second, focus groups (including 30 patients) were conducted for wording, layout, clarity and relevance of the items. Third, the items were translated and cognitive interviews (including 60 patients) were conducted on the English, Spanish, Korean and Mandarin-Chinese translated versions to ensure comprehension and interpretation. Finally, the resulting pool of 227 items was then used to conduct a pilot case-control study that enrolled 30 participants with gastric cancer and 60 participants without cancer from two sites, including Montefiore Medical Center in Bronx, NY and Queens Medical Center in Queens, NY.

The results of this pilot study showed that ethnic and immigration items were highly predictive. While this study was conducted in a small number of participants and the magnitude of the effect needs to be further investigated, in particular, being foreign born had 15 times higher odds, (odds ratio [OR]=15.8, 95% concordance interval [CI] 95%CI 2.0-123.1) and reporting daily consumption of cultural foods had 25 times higher odds of having gastric cancer.  (OR=25.1, 95%CI 2.0-308.2) were highly predictive of gastric cancer. In addition, the study showed promise that a parsimonious model with as few as five to seven items had potential to identify a cohort with seven to 10 times higher gastric cancer risk than the general population.7 These factors are not well investigated for gastric cancer risk, but show potential to be used to identify persons that would benefit from screening. The results of this study were recently published as the feature article and the cover of the July 2018 edition of the Journal of Surgical Research.

With appropriate targeting, gastric cancer screening can be feasible in the U.S. A tool to identify persons at high risk, by necessity, must be easy and inexpensive to use in both clinical and community settings, so that it can draw in high-risk individuals into the healthcare system for further testing. Such a short prescreening questionnaire has the potential to become a handy non-invasive tool that can be used to identify persons at high risk during a usual wellness visit in a hospital setting or in a community setting. The high-risk persons can thereafter undergo a screening endoscopy. Identification of individuals at higher risk and subsequent endoscopy screening would make the screening of gastric cancer feasible and cost-effective in a low-incidence population as in the U.S. These exciting results were recently used as preliminary data for a National Institutes of Health grant proposal to conduct a large-scale, case-control study to develop a stable risk prediction model for gastric cancer using demographics, diet and lifestyle factors. If accepted, participants will be recruited from the Alliance for Clinical Trials in Oncology academic centers and the NCI Community Oncology Research Program community sites.

 

References

1. Siegel RL, Fedewa SA, Miller KD, et al. Cancer statistics for Hispanics/Latinos, 2015. CA: a cancer journal for clinicians. 2015;65(6):457-480.
2. Lui FH, Tuan B, Swenson SL, Wong RJ. Ethnic disparities in gastric cancer incidence and survival in the USA: an updated analysis of 1992-2009 SEER data. Digestive diseases and sciences. 2014;59(12):3027-3034.
3. Haile RW, John EM, Levine AJ, et al. A review of cancer in U.S. Hispanic populations. Cancer prevention research (Philadelphia, Pa). 2012;5(2):150-163.
4. Gomez SL. Cancer incidence trends among Asian American populations in the United States, 1990-2008. Journal of the National Cancer Institute. 2013;105(15):1096-1110.
5. Liu L, Noone AM, Gomez SL, et al. Cancer incidence trends among native Hawaiians and other Pacific Islanders in the United States, 1990-2008. J Natl Cancer Inst. 2013;105(15):1086-1095.
6. Uthman O, Jadidi E, Moradi T. Socioeconomic position and incidence of gastric cancer: a systematic review and meta-analysis. J Epidemiol Community Health. 2013;67(10):854-860.
7. In H, Langdon-Embry M, Gordon L, et al. Can a gastric cancer risk survey identify high-risk patients for endoscopic screening? A pilot study. The Journal of surgical research. 2018;227:246-256.

 

 

For other articles in this issue of the Alliance E-News newsletter, see below.