Gender, racial, and stage-specific trends in esophageal cancer: Insights from longitudinal population data

Abstract

BACKGROUND

Esophageal cancer is a significant global health concern, characterized by high mortality rates and diverse histological types, primarily adenocarcinoma and squamous cell carcinoma.

AIM

To analyze trends in esophageal cancer using Surveillance, Epidemiology, and End Results (SEER) data, focusing on patient characteristics, stage at diagnosis, treatment modalities, and survival outcomes, to provide insights that may guide clinical practice and public health initiatives.

METHODS

Age-adjusted incidence and mortality rates for esophageal cancer, 2004-2021, were obtained from SEER rate sessions using SEER*Stat version 8.4.4. Average percent changes (APC) over time in age-adjusted incidence and mortality rates relative to gender, race/ethnicity, and stage at diagnosis were assessed using Joinpoint’s log-linear regression. Finally, Poisson regression was used to ascertain incidence and mortality rate ratios to ascertain associations between age, gender, race/ethnicity, and staging with incidence and mortality rates. All analyses were further stratified by gender to assess interactions between gender and the other demographic and clinical characteristics.

RESULTS

Overall, the data reveals significant trends in both the incidence and mortality rates of esophageal cancer, with notable variations across gender, race, and stage at diagnosis. Age-adjusted incidence and mortality rates were higher in males compared to females (incidence: 4.1 per 100000 vs 0.9 per 100000, mortality: 3.4 per 100000 vs 0.7 per 100000), P < 0.001. Furthermore, the APC among males decreased more significantly over time [APC (95%CI): -1.14 (-1.52 to -0.78); P < 0.001]. Both non-Hispanic (NH) Blacks and NH Whites showed significant decreases in cancer incidence, with NH Blacks observing a 3.27% decline and NH Whites a 0.51% decline. Patients with distant staging had a 5% APC increase in mortality rates over time (P = 0.003). Additionally, mortality rates increased with age, and all minority groups showed declines in incidence and mortality compared to NH Whites. Cancer diagnosed at a distant stage had a mortality rate 4.16 times higher than in situ cases.

CONCLUSION

The analysis reveals clear disparities in both the incidence and mortality of esophageal cancer, with males, particularly NH Whites, experiencing significantly higher rates than females. Despite a general decline in incidence rates over time, the upward trend in mortality for certain subgroups warrants further investigation into potential contributing factors such as healthcare access, treatment efficacy, and underlying socio-economic disparities.

Key Words: Esophageal cancer; Incidence; Mortality; Surveillance, Epidemiology, and End Results; Epidemiology

Core Tip: This population-based study uses Surveillance, Epidemiology, and End Results data (2004-2021) to assess trends in esophageal cancer incidence and mortality by demographic and clinical characteristics. While overall incidence is declining - particularly among males and non-Hispanic Black individuals - mortality remains disproportionately high in older adults, males, and those with distant-stage disease. Notably, non-Hispanic Whites show a concerning upward trend in mortality. These findings highlight persistent disparities and underscore the need for targeted prevention, early detection, and improved treatment strategies.

INTRODUCTION

Esophageal cancer remains a public health concern worldwide due to its poor prognosis and aggressive nature of the disease. The esophagus, a vital organ responsible for transporting food and liquids from the mouth to the stomach, becomes a battleground when infiltrated by cancerous cells. Esophageal cancer is the seventh leading cause of cancer mortality worldwide[1]. Two major pathological subtypes exist: (1) Esophageal squamous cell carcinoma; and (2) Esophageal adenocarcinoma[2]. Epidemiological studies in the last decade have shown a gradual increase in the incidence of esophageal adenocarcinoma worldwide[3]. Esophageal cancer remains an integral cause of cancer-related death and has shown a drastic increase of more than 6-fold in incidence rates (IRs) worldwide as per the year 2020[4]. With a spiked increase in incidence being observed in certain Western countries, 5-year survival rates (SRs) have been shown at rates of 10%-15%[5]. Despite advances in treatment modalities, the five-year SR remains dismally low.

The Surveillance, Epidemiology, and End Results (SEER) database provides a comprehensive and large-scale dataset that allows for the examination of the trends with a high degree of statistical power. Analyzing updated data ensures that public health strategies are informed by the most current and accurate information, guiding efforts to reduce disparities and improve outcomes for all populations affected by esophageal cancer. An updated analysis helps assess whether recent shifts in healthcare access, early detection practices, or treatment protocols have influenced staging trends and patient outcomes over time. It has been reported that there is an increased risk of esophageal adenocarcinoma diagnosis for people older than 50 years[6]. Various risk factors, including chronic gastroesophageal reflux disease, tobacco, obesity and dietary habits with diet low in vegetables and fruits is associated with esophageal adenocarcinoma. Smoking and alcohol consumption contribute to esophageal squamous cell carcinoma[7]. Moreover, the complex interplay of genetic predisposition, environmental factors, and epigenetic modifications adds layers of complexity to its pathophysiology.

Early detection of esophageal cancer is challenging due to the absence of specific symptoms in the early stages of the disease. Current diagnostic modalities include endoscopy, imaging techniques (such as computed tomography, magnetic resonance imaging, and positron emission tomography scans), and minimally invasive procedures such as endoscopic ultrasound and endoscopic mucosal resection[8]. Despite advances in treatment options, the management of esophageal cancer remains complex and often involves a multimodal approach, including surgery, chemotherapy, radiation therapy, and targeted therapies. Continued research efforts and collaborative initiatives are needed to address the challenges posed by this devastating disease. Esophageal cancer is relatively rare; however, the incidence appears to be on the rise in the developed countries. The aim of this study is to evaluate the racial differences in esophageal cancer trends of IR, disease staging at diagnosis, and SR. This health care disparity needs to be studied further and addressed. This study highlights the importance of racial disparities and trends due to social determinants of health playing a role, health literacy and access to care.

MATERIALS AND METHODS

Data and population

Age-adjusted incidence and incidence-based mortality rates for esophageal cancer were derived from the SEER rate sessions using SEER*Stat version 8.4.4[9]. SEER is a national cancer database supported by the United States National Cancer Institute, providing publicly available and authoritative cancer statistics. It is a well-recognized and robust source of population-based cancer statistics, ensuring a high-quality data foundation for analysis. The rates were obtained from SEER research data spanning from 1992 to 2021, which includes information from 12 registries across the United States[10,11]. The dataset incorporated variables such as age, gender (male vs female), race/ethnicity [non-Hispanic (NH) White, NH Black, NH Asian/Pacific Islander (PI), NH American Indian/Alaskan Native (AI/AN), Hispanic of all races], and staging at diagnosis (in situ, localized, regional, distant). However, records were excluded from the analysis if the race/ethnicity status or staging at diagnosis was missing or unknown. Consequently, the data from 2004 served as the initial year for both diagnosis and mortality.

Statistical analysis

Age-adjusted incidence and incidence-based mortality rates per 100000 people were calculated separately based on gender status, race/ethnicity, and staging at diagnosis. These rates were further stratified by gender to assess gender as a potential effect modifier. Second, trend analysis using log-linear regression modeling was implemented to calculate average percent changes (APC) in incidence and mortality rates relative to gender, race/ethnicity, and stage at diagnosis. Furthermore, APCs were further stratified by gender to assess whether trends within racial/ethnic and stage at diagnosis subgroups were modified by gender status. Finally, multivariable Poisson regression was used to ascertain incidence and mortality rate ratios (MRRs) relative to patient demographics. All APCs were calculated using the Joinpoint program[12], while Poisson regression was conducted using STATA version 18 (StataCorp; College Station, TX, United States).

RESULTS

Incidence and mortality rates

Overall, the trends reveal significant increase in both the incidence and mortality rates of esophageal cancer, with notable variations across gender, race, and stage at diagnosis. Table 1 reports the esophageal cancer age-adjusted incidence and mortality rates relative to demographic covariates. Data indicate a higher IR of esophageal cancer among males compared to females, with rates of 4.1 cases per 100000 vs 0.9 cases per 100000 individuals, respectively. Additionally, NH Whites exhibit the highest rates across all racial and ethnic categories, reporting 2.7 cases per 100000. In contrast, NH Asian/PI have the lowest rates, at 1.5 cases per 100000. Notably, no cases of esophageal cancer were diagnosed as in situ. The highest rates of diagnosed esophageal cancer were classified as distant staging, with an incidence of 1.0 case per 100000. Stratification by gender reveals that NH white males continue to show the highest cancer rates compared to other racial and ethnic groups, at 4.6 cases per 100000. The male NH AI/AN population follows as having the second highest rates. Among females, the NH AI/AN group reported the highest cancer rates, while NH Asian and Hispanic females had the lowest rates, at 0.6 cases per 100000. In the male population, distant and regional staging exhibited the highest IRs of esophageal cancer, at 1.8 cases per 100000 and 1.4 cases per 100000, respectively. Conversely, among females, regional staging demonstrated the highest rates, followed by distant staging.

Table 1 Age-adjusted rates.

Variables	Overall	Male	Female
Incidence [age-adjusted rate (95%CI) per 100000 people]
Sex
Male	4.1 (4.0-4.1)	N/A	N/A
Female	0.9 (0.9-1.0)	N/A	N/A
Race/ethnicity
NH White	2.7 (2.6-2.7)	4.6 (4.5-4.7)	1.0 (1.0-1.0)
NH Black	2.2 (2.1-2.3)	3.6 (3.4-3.8)	1.2 (1.4-1.4)
NH AI/AN	1.9 (2.6-3.3)	4.4 (3.8-5.1)	1.6 (1.3-2.0)
NH Asian/PI	1.5 (1.4-1.5)	2.6 (2.4-2.7)	0.6 (0.5-0.7)
Hispanic	1.7 (1.6-1.8)	3.1 (2.9-3.2)	0.6 (0.5-0.7)
Staging
In situ	0.0 (0.0-0.0)	0.0 (0.0-0.0)	0.0 (0.0-0.0)
Localized	0.5 (0.5-0.5)	0.9 (0.9-0.9)	0.2 (0.2-0.3)
Regional	0.8 (0.8-0.8)	1.4 (1.4-1.4)	0.4 (0.3-0.4)
Distant	1.0 (1.0-1.0)	1.8 (1.7-1.8)	0.3 (0.3-0.4)
Mortality [age-adjusted rate (95%CI) per 100000 people]
Sex
Male	3.4 (3.4-3.5)	N/A	N/A
Female	0.7 (0.7-0.8)	N/A	N/A
Race/ethnicity
NH White	2.1 (2.1-2.2)	3.8 (3.7-3.9)	0.8 (0.8-0.8)
NH Black	2.0 (1.9-2.1)	3.3 (3.1-3.5)	1.1 (1.0-1.2)
NH AI/AN	2.5 (2.2-2.8)	3.8 (3.2-4.5)	1.4 (1.1-1.8)
NH Asian/PI	1.2 (1.1-1.2)	2.1 (2.0-2.2)	0.4 (0.4-0.5)
Hispanic	1.4 (1.3-1.5)	2.6 (2.5-2.8)	0.5 (0.4-0.5)
Staging
In situ	0.0 (0.0-0.0)	0.0 (0.0-0.0)	0.0 (0.0-0.0)
Localized	0.4 (0.3-0.4)	0.6 (0.6-0.7)	0.2 (0.2-0.2)
Regional	0.6 (0.6-0.7)	1.1 (1.1-1.2)	0.3 (0.2-0.3)
Distant	0.9 (0.9-0.9)	1.6 (1.6-1.7)	0.3 (0.3-0.3)

AI/AN: American Indian/Alaskan Native; N/A: Not applicable; NH: Non-Hispanic; PI: Pacific Islander; CI: Confidence interval.

In terms of mortality rates, males exhibit significantly higher rates compared to females, with 3.4 cases per 100000 vs 0.7 cases per 100000, respectively (Table 1). Unlike cancer incidence, NH AI/AN individuals show the highest mortality rates among all racial and ethnic groups, followed by NH Whites. Mortality rates associated with staging at diagnosis reflect similar trends to those observed in cancer incidence; more severe staging correlates with higher mortality rates, ranging from 0 case per 100000 to 0.9 cases per 100000. After stratification by gender, NH Whites and NH AI/AN individuals exhibit equal mortality rates within the male subgroup, while NH Asian/PI report the lowest rates among males. In the female population, NH AI/AN individuals continue to show the highest mortality rates at 1.4 cases per 100000, whereas Hispanic and NH Asian/PI report the lowest mortality rates. Consistent with trends observed in the overall population, an increase in mortality rates is evident as the severity of cancer staging rises among males. Among females, regional and distant staging demonstrate equal mortality rates.

Incidence and mortality rate trends

The annual percent change indicated a statistically significant decrease in cancer incidence over time for both males and females (Figure 1A). However, the reduction was slightly more pronounced in the male subgroup [APC (95%CI): -1.14 (-1.52 to -0.78); P < 0.001]. NH Blacks and NH Whites both exhibited statistically significant decreases in cancer incidence over time. Specifically, NH Blacks experienced a 3.27% decrease in incidence [APC (95%CI): -3.27 (-4.18 to -2.39); P < 0.001], while NH Whites showed a more modest decline of 0.51% [APC (95%CI): -0.51 (-0.93 to -0.09); P = 0.022]. Among the stages at diagnosis, only patients diagnosed with localized staging demonstrated a statistically significant decrease in cancer incidence over time, with rates ranging from 1% to 0.75% [APC (95%CI): -2.29 (-3.73 to -1.11); P = 0.002]. Male NH Blacks exhibited a decreasing APC [APC (95%CI): -3.54 (-4.74 to -2.33); P < 0.001], similarly female NH Blacks individuals showed a decreasing APC [APC (95%CI): -3.40 (-5.29 to -1.41); P = 0.003]. In contrast, male NH Whites exhibited a decreasing APC [APC (95%CI): -0.75 (-1.13 to -0.28); P = 0.004], while female NH AI/AN individuals showed an annual decrease of 1.88% [APC (95%CI): -1.88 (-3.41 to -0.077); P = 0.039; Table 2].

Figure 1 Annual percent change in age-adjusted rates of esophageal cancer by sex, race/ethnicity and stage at diagnosis. A: Incidence rates; B: Mortality rates. AI/AN: American Indian/Alaskan Native; APC: Average percent changes; PI: Pacific Islander.

Table 2 Annual percent change in age-adjusted incidence rates of esophageal cancer by race/ethnicity and stage at diagnosis stratified by sex.

	Male	P value	Female	P value
Incidence [annual % change (95%CI)]
Race/ethnicity
NH White	-0.75 (-1.13 to -0.28)	0.004	-0.11 (-1.17 to 0.92)	0.79
NH Black	-3.54 (-4.74 to -2.33)	< 0.001	-3.40 (-5.29 to -1.41)	0.003
NH AI/AN	-0.62 (-2.28 to 1.40)	0.56	-1.88 (-3.41 to -0.077)	0.039
NH Asian/PI	1.67 (-2.06 to 6.52)	0.31	-2.67 (-6.80 to 2.17)	0.27
Hispanic	-0.97 (-2.71 to 1.07)	0.35	-0.064 (-2.27 to 2.60)	0.95
Staging
In situ	N/A		N/A
Localized	-2.76 (-4.24 to -1.58)	< 0.001	-1.98 (-4.48 to 0.12)	0.059
Regional	-0.73 (-1.81 to 0.32)	0.14	-0.40 (-1.39 to 0.56)	0.39
Distant	-0.43 (-1.00 to 0.13)	0.12	-14.096 (-2.54 to 0.35)	0.12
Mortality [annual % change (95%CI)]
Race/ethnicity
NH White	1.03 (-0.22 to 2.39)	0.11	0.65 (-0.60 to 2.01)	0.32
NH Black	-1.98 (-4.36 to 0.67)	0.14	-0.78 (-2.97 to 1.53)	0.51
NH AI/AN	3.09 (-0.53 to 8.28)	0.091	-0.091 (-4.68 to 6.73)	0.83
NH Asian/PI	-0.14 (-1.64 to 1.65)	0.95	-0.67 (-3.02 to 2.52)	0.76
Hispanic	0.50 (-0.63 to 1.81)	0.36	2.24 (0.42-4.99)	0.021
Staging
In situ	N/A		N/A
Localized	0.71 (-0.82 to 2.39)	0.35	0.23 (-1.62 to 2.30)	0.82
Regional	0.92 (-0.39 to 2.42)	0.17	0.86 (-0.50 to 2.36)	0.22
Distant	0.22 (-1.00 to 1.47)	0.68	-0.051 (-1.39 to 1.49)	0.93

AI/AN: American Indian/Alaskan Native; N/A: Not applicable; NH: Non-Hispanic; PI: Pacific Islander; CI: Confidence interval.

Statistically significant trends in mortality rates were not observed in relation to gender. Patients with distant staging exhibited a fivefold increase in mortality rates (P = 0.003; Figure 1B). Upon stratification by gender, male NH AI/AN populations demonstrated a trending increase in mortality rates [APC (95%CI): 3.09 (-0.53 to 8.28); P = 0.091] which is not statistically significant. Among females, Hispanic individuals experienced a 2.24% increase in mortality rates over time (P = 0.021). No statistically significant changes in mortality rates were seen within any staging subgroups in males or females.

Incidence and MRRs

Table 3 presents the IR ratios (IRRs) for esophageal cancer concerning age categories, gender, race/ethnicity, and year of diagnosis. In the overall population, the IRRs for age categories exhibit a positive trend relative to the reference group of individuals aged < 20 years. Notably, patients aged 40-49 years observed a five-fold increase in cancer rates compared to the reference group. This rate escalates significantly to a 16-fold increase for individuals aged 50 years or older [IRR (95%CI): 16.6 (14.8-18.6); P < 0.001]. Furthermore, the IR for females is 68% lower than that for males (P < 0.001). Additionally, cancer rates among NH minority groups and the Hispanic group are statistically lower than those of NH Whites, with reductions ranging from 85% to 96%. Regarding cancer staging at diagnosis, a higher IR correlates with more severe stages. For example, cancer diagnosed at a distant stage has a 4.5-fold higher incidence compared to the in situ category. Among the male cohort, the increase in cancer rates with age results in higher rate ratios than in females. Both genders exhibit a marked increase in cancer incidence upon reaching 50 years of age; however, the IR for males aged 50-59 years is 26.2-fold higher than the reference group, whereas the same age group for females shows only a 6.8-fold increase (P < 0.001). In both NH minority and Hispanic groups, cancer rates are statistically lower compared to NH Whites. The decline in cancer rates is more significant among males, with reductions between 86% and 97%, while the decrease for females ranges from 83% to 91%. Like age-related trends, IRs for males show a higher prevalence of regional and distant staging at diagnosis (P < 0.001) compared to females.

Table 3 Incidence rate ratios to associate the rate of esophageal cancer incidence with age, sex, race and stage at diagnosis.

Variables	Overall [IRR (95%CI)]	P value	Males [IRR (95%CI)]	P value	Females [IRR (95%CI)]	P value
Age
< 20	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001
20-29	1.13 (0.97-1.32)		1.21 (0.97-1.49)		1.06 (0.84-1.32)
30-39	1.71 (1.48-1.97)		2.21 (1.82-2.68)		1.21 (0.97-1.50)
40-49	4.98 (4.40-5.64)		7.61 (6.42-9.02)		2.34 (1.93-2.83)
50-59	16.6 (14.8-18.6)		26.2 (22.3-31.8)		6.88 (5.79-8.16)
60-69	28.5 (25.4-31.9)		45.8 (39.0-53.8)		11.1 (9.38-13.1)
70-79	25.2 (22.4-28.3)		37.9 (32.3-44.6)		12.3 (10.4-14.5)
80 +	15.4 (13.7-17.3)		20.8 (17.7-24.5)		9.88 (8.35-11.7)
Sex
Male	Reference	< 0.001	N/A		N/A
Female	0.32 (0.31-0.33)		N/A		N/A
Race
NH White	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001
NH Black	0.12 (0.11-0.12)		0.096 (0.091-0.10)		0.19 (0.18-0.21)
NH American Indian/Alaskan Native	0.04 (0.036-0.042)		0.028 (0.026-0.031)		0.077 (0.068-0.086)
NH Asian/Pacific Islander	0.13 (0.13-0.14)		0.12 (0.11-0.13)		0.17 (0.15-0.18)
Hispanic	0.15 (0.14-0.15)		0.14 (0.14-0.15)		0.16 (0.14-0.18)
Staging
In situ	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001
Localized	2.47 (2.35-2.58)		3.68 (3.46-3.93)		1.24 (1.15-1.34)
Regional	3.81 (3.64-3.98)		5.85 (5.50-6.22)		1.76 (1.64-1.89)
Distant	4.57 (4.37-4.78)		7.43 (6.99-7.89)		1.71 (1.59-1.84)
Year of diagnosis	1.09 (1.08-1.09)	< 0.001	1.09 (1.09-1.10)	< 0.001	1.08 (1.08-1.08)	< 0.001

Poisson regression adjusting for all other variables. IRR: Incidence rate ratio; N/A: Not applicable; NH: Non-Hispanic; CI: Confidence interval.

MRRs for age categories observed an increasing trend relative to the reference group of individuals aged < 20 years. Similar to cancer incidence, patients aged 40-49 years observed a 3.5-fold increase in cancer mortality rates compared to the reference group. This rate increases significantly to an 11-fold increase for patients aged 50 years or older [IRR (95%CI): 11.4 (10.1-12.8)); P < 0.001]. Additionally, the mortality rate showed a 68% decrease in females compared to males (P < 0.001). Mortality rates for NH minority groups and the Hispanic population are statistically lower than those of NH Whites, with reductions between 85% and 95%. In terms of cancer staging at diagnosis, higher mortality rates were associated with more advanced stages. Specifically, cancer diagnosed at a distant stage had a mortality rate that is 4.16 times higher than that of in situ cases. After stratifying by gender, the increase in cancer mortality rates with age led to higher rate ratios for males compared to females. Both sexes experience a significant increase in mortality after turning 50 years of age; however, the mortality rate for males aged 50-59 was 18.1 times greater than that of the reference group, while the same age group for females showed only a 4.64-fold increase (P < 0.001). In both NH minority and Hispanic groups, mortality rates are statistically lower than those of NH Whites. The decline in cancer rates is more significant among males, with reductions between 86% and 97%, while the decrease for females ranges from 83% to 91%. Like age-related trends, IRs for males show a higher prevalence of regional and distant staging at diagnosis (P < 0.001) compared to females (Tables 3 and 4).

Table 4 Incidence rate ratios to associate the rate of esophageal cancer mortality with age, sex, race and stage at diagnosis.

Variables	Overall [IRR (95%CI)]	P value	Males [IRR (95%CI)]	P value	Females [IRR (95%CI)]	P value
Age
< 20	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001
20-29	1.06 (0.90-1.24)		1.09 (0.88-1.37)		1.03 (0.81-1.28)
30-39	1.42 (1.22-1.65)		1.70 (1.39-2.09)		1.14 (0.92-1.41)
40-49	3.42 (3.01-3.89)		5.17 (4.34-6.15)		1.66 (1.36-2.04)
50-59	11.4 (10.1-12.8)		18.1 (15.4-21.4)		4.64 (3.88-5.53)
60-69	20.9 (18.7-23.5)		33.9 (28.9-39.8)		7.89 (6.66-9.35)
70-79	21.1 (18.8-23.7)		32.2 (27.4-37.9)		9.98 (8.43-11.8)
80 +	16.6 (14.9-18.9)		23.3 (19.8-27.4)		10.3 (8.70-12.2)
Sex
Male	Reference	< 0.001	N/A		N/A
Female	0.32 (0.31-0.33)		N/A		N/A
Race
NH White	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001
NH Black	0.13 (0.12-0.14)		0.11 (0.10-0.11)		0.21 (0.19-0.23)
NH American Indian/Alaskan Native	0.045 (0.042-0.049)		0.032 (0.029-0.036)		0.091 (0.081-0.10)
NH Asian/Pacific Islander	0.13 (0.13-0.14)		0.12 (0.12-0.13)		0.17 (0.15-0.18)
Hispanic	0.15 (0.15-0.16)		0.15 (0.14-0.15)		0.17 (0.16-0.19)
Staging
In situ	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001
Localized	1.60 (1.52-1.68)		2.36 (2.21-2.53)		0.84 (0.77-0.91)
Regional	2.91 (2.78-3.05)		4.53 (4.25-4.82)		1.30 (1.20-1.40)
Distant	4.16 (3.98-4.35)		6.76 (6.37-7.19)		1.56 (1.45-1.67)
Year of diagnosis	1.10 (1.09-1.10)	-	1.10 (1.10-1.11)	-	-	-

Poisson regression adjusting for all other variables. IRR: Incidence rate ratio; N/A: Not applicable; NH: Non-Hispanic; CI: Confidence interval.

DISCUSSION

This study aimed to analyze the incidence and survival trends in esophageal cancer over a 20-year period using data from the SEER database. The results highlighted substantial disparities based on age, gender, race, and stage at diagnosis, with males exhibiting significantly higher rates of incidence and mortality compared to females. Moreover, NH White individuals showed the highest rates of incidence among racial groups, while NH AI/AN populations had the highest mortality rates. These findings emphasize the importance of targeted public health initiatives, such as improved early detection strategies and tailored interventions for high-risk groups, including older males and certain racial/ethnic populations. This research provides critical insights that could shape future clinical practices and policies, offering a pathway to reduce the global burden of esophageal cancer[12-14].

The results are aligned with similar studies published in high-impact journals such as the Journal of Clinical Oncology and Cancer Epidemiology, which have also reported gender and racial disparities in esophageal cancer outcomes[15-17]. For instance, a study in Cancer Causes and Control corroborates the observed reduction in incidence among males over time and the significant influence of age on cancer outcomes[18]. By leveraging a comprehensive dataset and aligning its methodology with established literature, this study provides credible and reproducible conclusions that resonate with the broader academic consensus[19].

The observed trends in incidence and mortality could be influenced by several factors beyond the studied variables. Lifestyle factors, such as smoking and alcohol consumption, are well-documented contributors to esophageal cancer risk and may account for the higher rates observed in males[20-22]. Additionally, disparities in access to healthcare, socioeconomic status, and comorbidities likely play a significant role, particularly in the disparities noted among racial and ethnic groups[23]. Geographic variations and differences in dietary patterns, as suggested by studies in Gastroenterology and Annals of Oncology, could also have contributed to the results[24,25]. Future studies integrating these factors are necessary to further elucidate their impact on esophageal cancer trends.

The overarching conclusion of this study is that esophageal cancer exhibits pronounced disparities in incidence and SRs based on demographic factors such as gender, age, and race. The declining IRs over time, particularly among males, represent a positive trend potentially attributable to reduced smoking rates and improved public health measures[26,27]. However, the persistently high mortality rates, especially among older populations and specific racial groups like NH AI/AN individuals, underscore the need for enhanced early detection strategies and equitable healthcare delivery to address these disparities effectively[28].

Despite its strengths, the study has limitations that should be acknowledged. The reliance on the SEER database, while comprehensive, may not capture data from all geographic regions or reflect national heterogeneity in cancer incidence and SRs[29]. Additionally, the analysis did not account for potentially influential variables such as lifestyle factors, environmental exposures, and genetic predispositions[30]. The lack of granular data on treatment modalities and their outcomes further limits the study’s capacity to assess the impact of evolving therapeutic approaches. Future research incorporating these elements would provide a more nuanced understanding of the observed trends.

Building on the findings, future investigations should prioritize the integration of individual-level data on lifestyle, genetic, and environmental risk factors to deepen our understanding of esophageal cancer etiology. Expanding the scope to include international datasets could provide a global perspective on the trends and disparities identified[31]. Moreover, studies exploring the effectiveness of targeted screening and prevention programs in high-risk populations could pave the way for more effective public health interventions. Advancements in molecular and genomic profiling also hold promise for identifying novel biomarkers and therapeutic targets, potentially transforming the clinical management of esophageal cancer[32].

CONCLUSION

The data presented highlight significant disparities in the incidence and mortality rates of esophageal cancer based on gender, race/ethnicity, and cancer staging. Males consistently exhibit higher incidence and mortality rates compared to females, with NH Whites showing the highest cancer rates across racial and ethnic groups. Age is a key factor, with a marked increase in both incidence and mortality rates after the age of 40, especially in those over 50. More advanced cancer stages, such as distant staging, are associated with higher rates of both incidence and mortality. Additionally, NH minorities, particularly AI/AN individuals, exhibit higher mortality rates compared to other groups. The findings also reveal a significant decrease in cancer incidence over time, particularly among NH Black populations. However, trends in mortality rates showed only minor changes, with some groups experiencing slight increases, particularly in more severe cancer stages. Overall, the study highlights targeted interventions addressing high-risk groups and more research into the causes and prevention of esophageal cancer, especially in males and certain racial/ethnic groups.