Literature on Cancer Disparities in the LGBTQ Population

A Review of the Scholarly Literature on Cancer Disparities in the LGBTQ Population

Abstract:

The LGBTQ population represents an unfocused group of individuals that are known to be at an increased risk for many medical complications. Most notably, this population has higher rates of anal, cervical and endometrial cancer than compared to their heterosexual counterpart. The selected articles in this review contain the cancer outcomes of interest and their prevalence in the LGBTQ community. These findings demonstrate the medical training and skills that are needed for more effective LGBTQ healthcare.

Introduction:

The lesbian, gay, bisexual, transgender, and queer (LGBTQ) population, often termed ‘sexual minorities’, are estimated to represent 23% of the American population. Sexual minorities represent a group of people from all races, religion, ethnicities, ages and socioeconomic status in the United States of America. While the LGBTQ population represents an increasingly larger section today, they are also disproportionately at an increased risk for many health complications when compared to their heterosexual counterparts. This review will focus on the heightened cancer disparities that the LGBTQ population is posed with. Along with increased risk, such a population often refrains from the utilization of healthcare services due to stigma that comes with being part of the LGBTQ community. Advancements in LGBTQ health were made to ammeloriate and buffer these health disparities; however, this population still requires more focus in medicine. Eliminating LGBTQ health disparities and enhancing efforts to improve LGBTQ health are necessary to ensure that LGBTQ individuals can lead healthy lives.

When compared to their heterosexual counterparts, LGBTQ populations are at an increased risk for many mental and physical health disparities. LGBTQ youths are 2 to 3 times more likely to attempt suicide in their lifetime and are more likely to be homeless. Gay men have higher rates of HIV and STIs than heterosexual men. Lesbians and bisexual females tend to have a higher BMI thus increasing their risk of chronic diseases. The transgender population has the highest rates HIV/STDs, mental illnesses, rates of self-inflicted harm than any section of the LGBTQ population.This population has the highest rates of substance abuse ranging from tobacco, alcohol, and other drugs.

Cancer rates are rising even with the advancements in medicine. This rise in cancer rate is heavily seen in the LGBTQ population, as this group is at an increased risk for a variety of cancers. This cancer disparity can be attributed to many health needs that are unique to this population. For example, lack of training on providing anal pap smears to men who have sex with men (MSM) lead to many missed diagnoses of anal cancer. While the spread of HPV is considered to be lower in women who have sex with women (WSW), lesbian and bisexual women are an often-overlooked group at risk for HPV infection and are estimated to have lower vaccination rates against HPV, explaining their higher rates of cervical cancer compared to sexually active heterosexual women.

In addition to lack of training, the LGBTQ population lifestyle choice increases their chances of certain cancers. Sexual monitories abuse substances as a form of coping mechanism to the additional stressors they are posed with. Most notably, tobacco abuse is highest in the LGBTQ population, increasing their risk of lung cancer.

Along with the increased risk factors, LGBTQ individuals experience barriers in accessing health insurance, causing them to not seek routine care. Current health insurance policies may not be accommodating to the needs of this population— not covering mental health services, hormone therapy, or gender affirmation surgery.Transgendered individuals often face legal issues when selecting insurance policies causing them to abstain from getting health insurance. Most importantly, the stigma and discrimination these individuals experienced in past visits causes them to not follow up. LGBTQ patients often feel uncomfortable and unsafe causing them to forgo them forgo any healthcare.

Overall, the risk factors are related to lifestyle, risky behavior, lack of knowledge of medical conditions, and decreased access to health care. The articles in this review pertain to the selected cancers and were also compared with previous information to see any trend changes; however, the representation of the LGBTQ community in research is low but manages to commence a field or research that is currently sparsed. Ultimately, addressing these diverse needs can further provide a better quality of life and prolong life expectancy in the LGBTQ population.

Methods:

Articles were generally selected based on the types of cancers believed to be significant such as:  anal, endometrial and cervical cancer.  These articles were also correlated to understand their impact on the LGBTQ community. Furthermore, they were cross-selected to emphasize prevalence of cancer in the LGBTQ community. Considering that data of this community is sparse, there was no specific exlcusion criteria as information from many journals were compiled into a comprehensive analysis that unfortunately were not LGBT oriented by their design.

Results:

Anal Cancer

While cancers of the anus and perianus are rare, there is some scientific literature highlighting the diagnosis rate of this cancer. Currently, it is suggested that cancer of the anus and perianus represent 0.4% of cancer in the United States and only 0.2% of individuals will be clinically diagnosed with such type of cancer. It is suggested that 1 out of 100,000 persons will die from anal cancer as this type of cancer has a low rate of metastasis.

Earlier studies have shown an increase risk of anal cancer in the gay population. As seen in a cohort study of individuals living in San Francisco; individuals were followed throughout the years of 1973 through 1999. It was found that when age, race, and county were adjusted— a higher incidence rate of anal cancer was noted in gay men living in San Francisco than compared to their heterosexual counterparts.  Such a study showed that the prevalence of anal cancer was highest for non-Hispanic White gay men with an incidence rate of 2%. These rates were most appreciated in the age group of 40-64 in this population showing an incidence rate of 3.7 cases per 100,000 in 1973–1978 to 8.6 cases per 100,000 in 1984–1990 and to 20 .6 cases per 100,000 in 1996–1999. This population had the greatest incidence rate of anal cancer than compared to their heterosexual counterparts.

A systematic review and meta-analysis of anal human papillomavirus (HPV) and its relation to anal neoplasm in the MSM population showed a positive linear relationship. In this cross-sectional study: these men were then reviewed and asked about screening techniques and denied ever getting screened for anal cancer via anal Pap smears, which detects the presence of the viral DNA in potential tumors of the anal canal. It showed that those men who assumed receptive roles in anal sex were at a higher risk for HPV infection and subsequently at a higher risk for anal cancer.

Effective health prevention is often missed when it comes to anal cancer in the MSM population. Most recently, a double blinded, placebo experimental controlled study of 602 MSM showed that rates of anal cancer was 13.0 percent in the experimental group that received the quadrivalent HPV vaccine that was protective to HPV strains 6, 11, 16, and 18. While for the group that received the placebo was 17.5 percent, showing a decrease of 54.2% in the experimental group as compared to the group that received the placebo. Along with testing, proper vaccination can help reduce the rates of HPV related anal cancer in the MSM population.

Endometrial Cancer

In 2017, approximately 61,380 new cases of endometrial cancer are predicted in the United States, as are approximately 10,920 endometrial cancer-related deaths. The estimated annual incidence of endometrial cancer is 25.1 cases per 100,000 women, and the annual mortality rate is approximately 4.4 cases per 100,000 women.When analyzing data from the Women’s Health Initiative, it reveals that older lesbian and bisexual women who never had sex with men had increased prevalence of endometrial cancer relative to heterosexual women. However, up until 2015, there was no published literature on the issue.

In order to fill this knowledge gap, a 2015 study utilized a sample of 370 lesbian-heterosexual sister pairs to investigate whether lesbians had a higher prevalence of endometrial cancer risk factors compared with their heterosexual sisters. The study utilized respondent-driven sampling which utilized data from 370 lesbian-heterosexual sister pairs aged 40 or older. The participants completed an anonymous survey about their health. For this project, the researchers explored the gynecological risk factors for cancer in these women.

The study yielded some interesting results. Compared with their sisters, lesbians had significantly more education, fewer pregnancies, less total months pregnant, fewer children, and fewer total months breast-feeding. Lesbians in this sample also tended to have higher BMI and with a trend towards exercising fewer times a week than their heterosexual sisters. Another risk factor that the study found was that use of oral contraception pills was lower among lesbians than their heterosexual sisters (40% vs. 60%). Other risk factors related to endometrial cancer, such as smoking and alcohol use were not significantly different.

Endometrial, or uterine, cancer is a prevalent gynecological malignancy that requires further investigation. Comparison data of U.S. women suggests that lesbians and bisexual women are significantly more likely to be obese, smoke cigarettes and abuse alcohol. All of these are notable cancer risk factors. Furthermore, they are significantly less likely than average to have ever used oral contraceptives and to have ever been pregnant or given birth to a live infant. Oral contraceptives, pregnancy and live births have been shown to be protective factors against endometrial cancer. Lesbians and bisexual women are also less likely than American women overall to have health insurance and to undergo cancer screenings. All these factors give insight into the fact that there is a generally increased risk of endometrial cancer in lesbian and bisexual women.

Cervical Cancer

Cancer of the uterine cervix is the third most common gynecologic cancer diagnosis and cause of death among gynecologic cancers in the United States. Almost 13,000 new cases of invasive cervical cancer and approximately 4100 cancer-related deaths occur each year. The annual incidence of uterine cervical cancer in the United States is approximately 7.7 cases per 100,000 women, and the mortality rate is 2.3 per 100,000 women per year. The California Health Interview Survey generated weighted prevalence estimates using 71,112 women where the data showed heterosexual women have a significantly lower prevalence of cervical cancer (14.0%) compared with lesbian women (16.5%) and bisexual women (41.2%). Although, these results may be generalized since sexual minority status are not obtained in national surveys and registries. In addition to the limiting factor just mentioned, there is no published data on cervical cancer incidence and mortality among lesbian and bisexual women.

The pathogenesis on cervical cancer involves the Human Papillomavirus (HPV), which is central to the development of cervical cancer; this makes HPV the most important and prevalent risk factor for cervical cancer. When HPV infection persists, the time from initial infection to cancer takes an average of 15 years, but some more rapid courses have been reported. Herpes simplex virus-2 (HSV-2) infection as a cofactor in cervical cancer pathogenesis has been reported in some studies. The risk of cervical cancer with co-infection of HSV-2 is being further investigated.

Previous studies have contributed to the misconception that sexually transmitted infections (STI’s) are rarely transmitted among lesbian women, but more recent studies have shown this is not true; STI’s are common among the lesbian population. Research reviewed by Waterman and Voss have shown many lesbians and their partners have had previous sexual contact with men and many lesbian woman may have higher rates of other cervical cancer risk factors and behaviors compared with heterosexual women due to higher body mass index scores, smoking, and involvement in high risk activities. Current data indicates additional risk factors for cervical cancer, which include early onset of sexual activity (younger than 18 years of age) which in this group risk is approximately 1.5-fold, multiple sex partners which in this group risk is approximately twofold with two partners and threefold with six or more partners, a high-risk sexual partner, history of STI’s, and immunosuppression.

The HVP vaccination, also known as Gardasil, plays a significant role in the prevention process. Although the vaccination has been proven to be effective, vaccination rates are low in the US and the vaccine is not recommended for women over the age of 27. Lesbian and bisexual women are an overlooked group at risk for HPV infection, this plays a huge role in the low numbers of vaccinations among lesbian and bisexual women. Studies have shown providers are not recommending the vaccine to this population due to misconception. To date, there are limited published data on HPV vaccination among lesbian and bisexual women. Bernat et al reported that 44.9% of lesbian and bisexual women ages 18 to 24 years received at least one dose of HPV vaccine compared to 51.1% of heterosexual women. A more recent study that surveyed a national sample of young adults ages 18 to 26 years who self-identified as LGBT found that 45% of respondents had initiated an HPV vaccine, and 70% of initiators reported completing the series. Studies have shown HPV vaccine initiation was higher among respondents who received a health care provider’s recommendation.

The “Pap Smear” is an effective method for screening to detect precancerous cervical abnormalities. Currently, cervical cancer guidelines do not include specific language or considerations for lesbian and bisexual women. Possibly due to misconceptions that lesbians and bisexual women are not at risk, these women may not be screened every 3 years as the general population. Cervical screening guidelines need to be changed to include sexual minority status. These guidelines may need to explicitly include language that lesbian and bisexual women may potentially be a vulnerable group.

Discussion:

Anal Cancer

Cancer of the anus and perianus represent a low number of cancer cases in the United States and often goes undiagnosed. Typical signs and symptoms tend to be nonspecific and unalarming. These signs and symptoms can often be falsely mistaken for other gastrointestinal complications; leaving the diagnosis of anal cancer as low in the differential rankings that are never worked up. It is suggested that anal cancer tends to be the last diagnosis to be worked up because of its low mortality rate and therefore not deemed as an immediate concern.

The cohort study conducted in San Francisco showed an increase in anal cancer diagnosis within the gay men population. However, its applicability to the general population is limited due to the study sample being a homogenous population. This study group was mainly composed of middle-aged non-Hispanic White who lived in San Francisco. While there is no strong relation between genetics and anal cancer, it is suggested that behavioral and environmental exposure may relate to this cancer. Therefore, the behavioral and environmental exposure that this specific population experiences may not be the same to other gay populations around the nation.

The LGBTQ population represent a growing sector in medicine that requires specific screening tests that is unknown to clinicians in primary care practices. Those diagnosed with anal cancer often denied ever getting an anal Pap smear simply because their provider was unaware of the test and its need to be part of routine health care prevention in the gay men population. In addition to Pap smears, vaccination against HPV has proven to lower the risk of anal cancer. The current recommendation is for both male and female individuals to be vaccinated against HPV for this very reason. This recommendation is often only stressesd in practice for females due to fear of cervical cancer and, unfortunately, left unoffered to men.

Endometrial Cancer

The 2010 Zaritsky study does have some limitations inherent to how it was conducted. The study had a small and homogeneous sample size, as the women were predominantly white, well-educated and from the same region. These factors make the results less generalizable to a larger and more diverse population. Furthermore, the participants were not selected through random sampling which results in a less diverse study group. This results in the study being susceptible to sample bias. Additionally, body measurements and medical and behavioral histories were self-reported which introduce another bias, especially as lesbian women are reported to have different perceptions regarding body image and weight relative to their heterosexual sisters. Further studies are necessary to examine if the increased risk factors result in an actual increased incidence of endometrial cancer within the lesbian community relative to the general population. Another point that could be further analyzed in future studies is whether lesbian and/or bisexual women are more or less likely to choose treatment options that are associated with reduced quality-of-life outcomes. A recent meta-analysis study suggests that obesity is associated with poorer quality of life in endometrial cancer survivors. This finding may be relevant for lesbian and bisexual women given the higher rates of obesity compared to heterosexual women.  Regardless of sexual orientation or gender identity, endometrial cancer screening is currently not recommended for asymptomatic women at average risk for this disease. In terms of clinical intervention, there are no direct implications for the care of lesbian women related to endometrial cancer screening. Regardless, this should not diminish the concern that lesbian and bisexual women may delay treatment or healthcare visits due to concerns about discrimination in the healthcare setting. It is essential that clinicians initiate the diagnostic process when patients present with symptoms that raise concern for endometrial cancer. It is of the utmost importance that health care providers create a welcoming environment that encourages patients to disclose their sexual health history, sexual orientation, gender identity, and all information that improves patient care and health outcomes. Furthermore, lesbian or bisexual patients may benefit from counseling regarding the use of oral contraceptives and diet control in order to reduce their risk factors. In conclusion, the lesbian and bisexual community is a unique population that requires a deep understanding on the part of the clinician to be treated optimally.

Cervical Cancer

Studies have proven that there is a clear correlation between lesbian and bisexual women and an increase in cervical cancer in this population. This is due to barriers to health care, screening, and vaccination among lesbian and bisexual women along with misconceptions that lesbian and bisexual women are not at risk for cervical cancer. Current data indicates the lesbian and bisexual woman population are more likely to have increased risk factors for cervical cancer as discussed in results. There are limited studies on cervical cancer that specifically focus on the lesbian/bisexual women group, therefore this group can be in a greater risk than what current studies have shown. Current studies do not discuss important factors that may put lesbians and bisexual women at an even greater risk. Such factors include race, age, socioeconomics, demographics, and genetics. The mean age at diagnosis of cervical cancer in the United States from 2000 to 2004 was 48 years. Women who are in their mid 40’s and identifies as lesbian or bisexual can be at an even higher risk. Cervical cancer estimates are higher for certain racial groups, Blacks and Hispanics are at an increased risk compared to Whites and Asians, this will put lesbians and bisexuals of a certain race at an even higher risk of cervical cancer. Low socioeconomic status is associated with an increased risk of cervical cancer. For women living in rural areas or in areas where differences in sexuality are not accepted, health care may not be easily accessible, and these women may be at an increased risk. Although there is no well-established model of a genetic basis for cervical cancer, population studies have shown an increased incidence of cervical cancer within families. Another important factor when discussing risk of cervical cancer that is not included in the above results is comorbidities, persons with an immunodeficient disease are at a greater risk of developing cervical cancer.

Conclusion:

When compared to their heterosexual counterparts, the LGBTQ population is disproportionately at a higher risk for many mental and physical illnesses. Prior research has only focused on mental illnesses and STI/HIV related infection. However, little is known about the rates of cancer in this population. In this review, it is shown that the LGBTQ population is at an increased risk for anal, breast, cervical, and endometrial cancer.

This relation is due to a multitude of reasons; as this population contains unique risk factors. These risk factors can be related to their lifestyle and inadequate knowledge of the unique stressors that pose this population. Most importantly, there is a lack of medical knowledge and training to provide effective care to this population. By increasing training and access to health to this population, it can significantly combat the increase risk of not only cancer rates, but also the other mental and physical conditions.

Appendix:

Table 1:  SEER Cancer Statistics Review, 1975-2014, National Cancer Institute

Table 2: SEER Cancer Statistics Review, 1975-2014, National Cancer Institute

Female Population, n=71,112	Heterosexual Women, n=69,078 (SE)	Lesbian Women, n=918 (SE)	Bisexual Women, n=1116 (SE)
Mean age, y [range, 18-85]	42.00 (0.02)	40.99 (0.62)	34.99 (0.61)
Race, %
White	50.32 (0.10)	70.30 (2.51)	56.43 (2.43)
Latino	26.14 (0.13)	14.44 (2.13)	18.26 (2.35)
Asian	12.82 (0.05)	3.69 (1.04)	11.21 (1.58)
African American	6.58 (0.04)	6.76 (1.37)	7.34 (1.05)
Other	4.14 (0.10)	4.81 (0.93)	6.76 (1.12)
Education, %
High school or lower	43.05 (0.20)	23.72 (2.31)	36.06 (2.27)
Some college/vocational school	18.80 (0.20)	17.95 (1.77)	20.94 (1.77)
Completed college	27.43 (0.22)	36.77 (2.41)	29.64 (2.25)
Greater than college	10.72 (0.14)	21.56 (1.73)	13.36 (1.18)
Household annual income, %
$0-30,000	37.23 (0.24)	27.83 (2.20)	39.24 (2.30)
$30,001-70,000	32.07 (0.25)	34.30 (2.22)	32.07 (2.01)
$70,001-100,000	15.43 (0.18)	14.15 (1.66)	13.33 (1.39)
$100,000	15.27 (0.17)	23.62 (1.77)	15.36 (2.07)
Insurance, %
Insured	84.33 (0.19)	82.72 (2.16)	82.30 (1.76)
Not insured	15.67 (0.19)	17.28 (2.16)	17.70 (1.76)
Nativity, %
US born	65.80 (0.21)	86.71 (1.87)	79.93 (1.87)
Foreign born	34.20 (0.21)	13.29 (1.87)	20.07 (1.87)

Table 3

:

Demographic Characteristics of the California Population by Sexual Orientation for the Years 2001, 2003, and 2005

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