Racial health disparities in ovarian cancer: not just black and white
Srivastava et al. Journal of Ovarian Research
Racial health disparities in ovarian cancer: not just black and white
Sanjeev K. Srivastava 0 1 3
Aamir Ahmad 0 1
Orlandric Miree 1
Girijesh Kumar Patel 1
Seema Singh 1 2
Rodney P. Rocconi
Ajay P. Singh 1 2
0 Equal contributors
1 Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama , 1660 Springhill Avenue, Mobile, AL 36604-1405 , USA
2 Department of Biochemistry and Molecular Biology, College of Medicine, University of South Alabama , USA
3 Division of Cell Biology and Genetics , Tatva Biosciences, Coastal Innovation Hub, 600 Clinic Drive, Mobile, AL 36688 , USA
Ovarian cancer (OC) is the most lethal gynecological malignancy, which disproportionately affects African American (AA) women. Lack of awareness and socioeconomic factors are considered important players in OC racial health disparity, while at the same time, some recent studies have brought focus on the genetic basis of disparity as well. Differential polymorphisms, mutations and expressions of genes have been reported in OC patients of diverse racial and ethnic backgrounds. Combined, it appears that neither genetic nor the socioeconomic factors alone might explain the observed racially disparate health outcomes among OC patients. Rather, a more logical explanation would be the one that takes into consideration the combination and/or the interplay of these factors, perhaps even including some environmental ones. Hence, in this article, we attempt to review the available information on OC racial health disparity, and provide an overview of socioeconomic, environmental and genetic factors, as well as the epigenetic changes that can act as a liaison between the three. A better understanding of these underlying causes will help further research on effective cancer management among diverse patient population and ultimately narrow health disparity gaps.
Ovarian cancer; Racial health disparity; Socioeconomic; Epigenetic
Background
Ovarian cancer (OC) is the most lethal of all
gynecologic malignancies [
1
]. Globally, OC is the 7th
most commonly diagnosed and the 8th leading cause
of cancer-related mortality among women [
2
].
According to estimates by the American Cancer
Society, 22,440 new OC cases and 14,080 associated
deaths will occur in 2017 [
1
]. It is a deadly disease
with no effective screening [
3
]. Approximately 70%
of patients with OC are diagnosed at an advanced
stage, with associated poor prognosis, even after
aggressive and immediate treatments [
4
]. Studies over
past several years have revealed that besides being
highly lethal, OC also disproportionately affects
some distinct racial populations, particularly the
black women of African American (AA) heritage, as
compared to the Caucasian Americans (CA) or white
women of European heritage. In fact, even with
higher incidence of OC in CA women in the United
States, the associated mortality is disproportionately
higher in AA women [
5
], and such disparities are
common worldwide [
6
]. Though the exact causes of
racial disparities in OC still remain unclear, they are
likely to be multifaceted and may include
sociocultural factors, acquired co-morbid conditions,
increased frequency of modifiable risk factors, access
to health care, diet and preventive health factors.
Emerging data suggests that several biological
factors, such as genetic, epigenetic etc., could be
more crucial than thought for health disparities in
OC incidence and outcome [
5, 7, 8
]. In this review
article, we have discussed, in-detail, various
biological and non-biological factors in racially disparate
clinical outcomes of OC.
Disparity in ovarian cancer incidence and mortality
While some progress has been made in OC treatment, it
has been observed that AA women with OC are not
reaping the same benefits of the advances as CA women.
Progress in management of OC patients has improved
over time but this progress has been relatively slow for
AAs [
9
]. The all-cause mortality of AA OC patients is
1.3 times higher, as compared to CA OC patients, even
when access to care is equal [
5
]. According to data from
SEER database, between the years 1992 and 2008, the
five-year survival rate for CA women rose from 40.7% to
45.0%, while the five-year survival for AA women fell
from 47.9% to 40.3%. For the years 2006 through 2012,
the reported 5 year survival of AA OC patients is
relatively poor, compared to CA OC patients, irrespective of
cancer stage at the time of diagnosis [
1
] (Table 1).
Although the overwhelming majority of all OC patients
are diagnosed at an advanced stage, it has been
suggested that AA women bear a greater burden in the late
diagnosis than CA women. Increased instances of late
diagnosis may be attributed to socio-economic factors
that will be discussed later in this article.
This disparity in survival may also be linked to observed
prevalence of comorbidities. Evidence shows that AA
women diagnosed wit (...truncated)