| Recently discovered mutations in
2 genes, BRCA1 and BRCA2, account
for most hereditary cases of breast cancer.
Individuals with mutations in either BRCA1
or BRCA2 carry an elevated lifetime risk
of breast or ovarian cancer. Genetic testing for
these mutations now allows individuals to learn
if they are at heightened cancer risk. This
genetic testing may have entered the health care
system without the development of adequate
notification protocols. This paper reviews the
psychological and behavioral sequelae of being at
increased risk for breast or ovarian cancer due
to personal or family history. Similar issues
relating to the BRCA1 and BRCA2
genetic screening and the notification process
also are discussed. |
reast cancer is a common illness
affecting approximately 1 in 8 women (1). Although most
breast cancers are sporadic, occurring in individuals
without a family cancer history, 5% to 10% of breast
cancer patients harbor an inherited mutation that
predisposes them to the development of breast and other
cancers (1, 2).
Recently
discovered mutations in 2 genes, BRCA1 and BRCA2,
are estimated to account for most hereditary breast
cancer cases. Inheritance is autosomal dominant; either
men or women may carry these genetic mutations. Incidence
rates of mutations found in BRCA1 and BRCA2
have varied from the initial linkage studies. These
incidence rates are lower in population-based studies.
Women who inherit a mutated form of either BRCA1
or BRCA2 have a 50% to 85% lifetime risk of
developing breast cancer (3, 4). Their lifetime chances
of developing ovarian cancer range from 15% to 45% for BRCA1
mutation carriers and from 10% to 20% for BRCA2
mutation carriers (4, 5). BRCA1 mutation
carriers also have an elevated risk of colon and prostate
cancer, whereas BRCA2 mutations are associated
with rare male breast cancer as well as other cancers (5,
6). Other genes may contribute to inherited breast
cancer, including p53 and PTEN (7, 8).
It is possible that additional cancer susceptibility
genes will be discovered in the future. Although
inherited mutations in other genes may play important
roles, BRCA1 and BRCA2 contribute to
most breast cancers with a hereditary cause.
BRCA1
and BRCA2 were identified and cloned in 1994 and
1995, respectively (6, 9). Genetic testing for these
breast cancer susceptibility genes is now commercially
available. This new technology has made it possible for
women in high-risk families and in the general population
to request genetic analysis. Lerman et al found that 91%
of first-degree relatives (FDRs) of breast cancer
patients intended to seek genetic evaluation when it
became available (10). Lerman believes that with
increasing medical and public interest and commercial
pressures, genetic testing will become an integral
component of routine medical care for this high-risk
population (11).
Technological
advances in molecular genetics presently are outpacing
research on the social and psychological effects of this
technology. Kodish and colleagues point out that the
recent identification of BRCA1 and BRCA2
breast cancer susceptibility genes has not allowed enough
time or experience to produce appropriate protocols for
distribution of this genetic status information (12).
Population-based clinical analysis of the effects of
these data on genetic mutation carriers is inadequate.
Multiple psychosocial concerns relate to the cancer
susceptibility risk notification process and potential
psychological sequelae that may affect those involved.
Examination of these issues has become more pressing, as
this technology makes its way from tightly controlled
research protocols to uncontrolled commercial
availability. An overview and understanding of the issues
associated with the risk notification process will enable
health care professionals to better serve the unique
needs of this high-risk population.
ASPECTS
OF GENETIC SCREENING
Pursuing
the discovery of disease-predisposing genes affords some
advantages (13). Individuals and society may benefit by
reducing the impact of disease, improving the health of
the population, and lowering the burden on the health
care system with the use of genetic information in
epidemiology, diagnosis, prognosis, and treatment.
Genetic screening provides new possibilities
(1315). Testing offers the ability to learn whether
one has a significantly heightened chance of developing
cancer or the potential to genetically transmit a
mutation to offspring. Individuals found to carry a
genetic mutation can be advised and encouraged to follow
breast cancer screening recommendations. Intensive
surveillance efforts may allow for earlier diagnosis in
these individuals and thereby culminate in decreased
morbidity and mortality. However, at present there is no
intervention proven effective for individuals who harbor
a mutation in either the BRCA1 or BRCA2
genes. The awareness of ones positive carrier
status can facilitate preventive medical decision-making
processes and enable health care providers to remain
vigilant for early indications of the disease. Carriers
can also practice preventive health behaviors that may
help avert the onset of the disease. Furthermore,
noncarriers have the opportunity to avoid taking
irrevocable actions such as prophylactic surgery (i.e.,
mastectomy or oophorectomy). Monitoring these patients
and continuing with this line of research may aid in the
discovery of improved cancer treatments or cures.
Concomitant
with the benefits of this recently accessible technology
come a variety of potential problems due to the multiple
unique aspects and limits involved in testing for breast
cancer genetic mutations (14, 16). It must be emphasized
that the information provided is qualitatively different
from the typical medical data provided to other patient
populations in several ways:
Unlike
most medical tests, positive genetic mutation
results provide information to individuals who
are typically healthy regarding potential future
risk. Therefore, these findings forecast events
that may transpire far into the future.
Test
results can predict where the cancer is likely to
occur and even provide some approximate time
frame.
There
is a large element of uncertainty in the meaning
of ones mutation carrier status, as genetic
susceptibility testing is probabilistic. Unlike a
definitive disease diagnosis, these mutated
susceptibility genes only confer an elevated
chance of developing these forms of cancers.
Thus, not everyone who harbors a mutation in a
breast cancer susceptibility gene will develop
the disease. The reality is more complex.
Additional genetic factors or environmental
events are necessary for the disease to be
expressed.
Inaccurate
or inconclusive genetic screening results are
plausible; therefore, breast cancer
susceptibility testing may not be reliable.
Genetic
test findings are pedigree sensitive. The
information can disclose the genetic status of
other family members. Issues related to
previously undisclosed nonpaternity may arise.
Test results are also likely to impact familial
dynamics. Lerman and Croyle believe it is
critical to discuss with these patients the
potential influence this information may have on
family relationships both before and after test
result notification (14).
There
are no guaranteed methods of primary breast
cancer prevention, and until the technology
exists to alter ones genome, harboring a
mutation in a breast cancer susceptibility gene
is permanent.
For those
identified to be BRCA1 or BRCA2
mutation carriers, treatment decisions must be reached
that may affect the rest of their lives. For example,
mutation carriers may consider whether to undergo
prophylactic mastectomy or oophorectomy (17). However,
this type of surgery does not completely eliminate the
risk of developing breast or ovarian cancer (1).
Moreover, prophylactic mastectomy patients must confront
issues regarding body image and sexuality. Some of these
patients may elect to undergo reconstructive surgery
following the mastectomy. Carriers may also choose to
enroll in clinical chemoprevention trials. Further, those
found to be mutation carriers must make reproductive
decisions. Issues related to prenatal genetic testing
have arisen and, concurrently, the question of whether to
continue the pregnancy if the fetus is identified as a
carrier (18). As can be surmised, genetic screening
information can be powerful; alterations in the course of
behaviors, plans, and even lives could result.
There
remain many unresolved questions regarding a range of
psychosocial issues (19). Confidentiality becomes a
matter of utmost importance, as uncertainty exists over
how to shield this genetic testing information and from
whom. Multiple concerns are being voiced regarding
predictive testing in healthy individuals, such as how to
prevent the possibility of quality of life
deterioration, social stigmatization, prejudice,
discrimination by employers and insurers (i.e., health,
life, disability), family stress, and psychological
stress (1, 17).
This new
ability to anticipate health threats can create auxiliary
factors that the individual and her family must address.
Ascertaining a womans motivation to seek genetic
screening will enable health care professionals to
respond more fully to her needs. In a population-based
screening program with high-risk women, Kash conducted
interviews with those being screened to determine their
interest in genetic evaluation (20). The most important
reason indicated was to obtain a degree of certainty,
preferring to hear bad news to none at all. Some believed
a positive status notification would help them increase
their breast cancer surveillance behaviors. Women also
sought genetic screening to assist them in their
decisions regarding marriage, future childbearing plans,
or the possibility of undergoing preventive procedures
such as prophylactic surgery. Others wished to learn the
genetic risk to their children or to inform family
members. Finally, some women believed learning their
genetic risk status would not assist them, but they
participated to further the research, thereby benefiting
others in the future.
The
reasons for not desiring to undergo genetic evaluation
are equally important to consider. A preference for
living with the uncertainty of not knowing the test
results is the overwhelming reason why high-risk women
decline genetic screening (20). Therefore, the decision
not to undergo genetic evaluation, in fact, may be the
most appropriate decision for some women. Breast cancer
surveillance behaviors have not yet proven to increase
survival from breast cancer in BRCA1 and BRCA2
mutation carriers. Neither is there a proven role for
surveillance and detection in ovarian cancer. Therefore,
some women prefer not to discover if they are at an
increased cancer risk. Others expressed concern regarding
the possible negative impact of a mutation carrier status
upon family members. Furthermore, many feel unable to
cope with positive results and do not want to deal with
the potential corresponding emotional consequences.
Desiring to avoid additional distress is not surprising
in light of evidence revealing that heightened levels of
psychological distress may be primary distinctions of
women having familial breast or ovarian cancer histories.
CHARACTERISTIC
FEATURES OF HIGH-RISK WOMEN
Characteristics
of BRCA1 and BRCA2 cancer expression
can manifest as increased disease incidence within these
high-risk families, and frequently with cancer onset at a
much younger age as compared with families not at high
risk. Disease expression may also include rare
phenotypes. The behavioral and psychological
ramifications associated with having a familial cancer
history can be far-reaching. Kash and associates contend
that these family cancer histories impact high-risk
womens lives because they live with fear, anxiety,
and uncertainty regarding their own and their loved
ones cancer risk every day (21). Compared with
normal controls, high-risk women experience significantly
more life events involving loss and illness such as
watching loved ones struggle with and sometimes succumb
to cancer. These adversities can have a psychological
impact, as Lerman and colleagues discovered (22). In
their population-based study of FDRs of breast cancer
patients, 53% reported intrusive thoughts about breast
cancer, 33% experienced daily functioning impairments due
to breast cancer worries, and 20% noted sleep
disturbances. Kash evidenced comparable findings in which
>50% of the high-risk women responding to a
self-report survey described psychological responses such
as anger, depression, guilt, sleep disturbance, and
emotional lability (20). Kash et al likewise found
increased levels of psychological distress in a
population of high-risk women (23). Twenty-seven percent
of these women manifested a level of psychological
distress consistent with a need for counseling. In a
follow-up study, Kash and colleagues documented similar
results, with their at-risk sample demonstrating
elevations in psychological distress one-half to 1
standard deviation above the mean, compared with women in
the general population (21). Such elevated levels are
directly attributable to the psychological impact these
disease characteristics have upon this population.
Furthermore, Lerman and Croyle reported that women with a
family history of ovarian cancer might be especially
vulnerable to psychological distress (14). The protracted
morbidity and high mortality rates associated with this
disease are believed to be the cause.
The
heightened psychological distress high-risk women
experience influences their willingness to engage in
breast cancer surveillance behaviors, such as
mammography, clinical breast examination (CBE), and
breast self-examination (BSE). These procedures are the
most recommended methods for breast cancer detection to
date for high-risk individuals (17). To be effective,
these techniques must be performed consistently.
Adherence to screening recommendations by high-risk women
is essential for detecting early signs of the disease,
for taking action, and for having a more positive
prognosis for survival. However, Kash and colleagues
documented that the higher the psychological distress
indexes, the lower the levels of adherence to guidelines
for CBE and BSE as well as general preventive health
behaviors practiced in their sample (23). Likewise, Kash
et al observed a negative relation between psychological
distress levels and the practice of CBE, BSE, and
mammography (21). Similarly, Lerman and Schwartz noted
that high-risk women attempted to alleviate their
anxiety, which was caused by intrusive thoughts about
breast cancer, by avoiding mammography adherence (24).
Therefore, it appears that some high-risk women may
attempt to allay distress by evading experiences related
to cancer, such as early detection screening measures.
Overestimation
of cancer risk is a major barrier to practicing early
detection methods and a primary contributor to heightened
levels of psychological distress (21). Kash et al assert
that a woman at risk for genetic breast cancer will
likely feel susceptible to the disease. This sense of
vulnerability leads to an overestimation of her cancer
risk which, in turn, serves to increase her subjective
certainty of developing the disease. In this study, 80%
of their high-risk sample overestimated their chances of
developing breast cancer by as much as 4 times the actual
rate. Consistent with these findings, an examination of
women at risk for developing ovarian cancer also
demonstrated that the higher their level of distress, the
greater their overestimation of their objective risk for
ovarian cancer (25).
A relation
between distorted cancer risk perceptions, heightened
distress indexes, and low levels of perceived control
over developing cancer are noted in high-risk subjects.
For example, Audrain and associates examined the
characterization of at-risk women self-referring for
genetic counseling and BRCA1 testing (26).
Results revealed that higher levels of general distress
are attributable to heightened breast cancer risk
perceptions, accompanied by low perceptions of control
over being afflicted with breast cancer. The
psychological distress that one may associate with the
development of cancer is referred to as cancer-specific
distress. These low perceptions of control significantly
contributed to higher levels of cancer-specific distress
as well. Moreover, cancer-specific distress can impact
the effectiveness of genetic counseling. The ability to
process information may be impaired by the
individuals emotional state at the time the
information is provided. For instance, Lerman et al
discovered that women experiencing heightened levels of
cancer-specific distress were more likely to continue to
overestimate their lifetime chances of developing breast
cancer following risk counseling versus women with lower
cancer-specific distress indexes (10).
Because
psychological distress can interfere with the
comprehension of risk information, Lerman and Croyle
raised important concerns regarding the medical
management of this population (14). Overestimation of
breast cancer risk may lead these patients to choose
preventive medical treatment options, such as
prophylactic surgeries, based upon erroneous beliefs
concerning personal risk.
Alterations
in psychological and behavioral functioning occur in some
high-risk women, who may be different from women in the
general population across a number of behaviors. Several
investigators have documented altered levels of
functioning in interpersonal relations and procreation
practices in their at-risk subjects. In comparison with
age-matched controls, Wellisch et al discovered
significant decrements in sexual satisfaction and in the
frequency of sexual activity in the daughters of breast
cancer patients they examined (27). Kash and associates
found that some at-risk women may have postponed marriage
or decided not to have children because they were certain
they would develop and ultimately die from breast cancer
(23). Recently, Croyle examined the variables of
fertility and the time at which at-risk women became
cognizant of their status (Croyle R: Genetic testing for
cancer susceptibility. Ann Behav Med: 18th
Annual Meeting 1997;19[suppl]:S036[SYM25]). Although the
women reported no awareness of their high-risk situation
having an impact upon their reproductive decisions, a
significant reduction in childbearing occurred relative
to the time of recognition of their at-risk profile. If
the FDR affected with breast cancer was the
patients mother, the effect did not manifest;
however, the consequence did occur when the
patients sister was afflicted.
POTENTIAL
PSYCHOLOGICAL REACTIONS TO GENETIC RESULTS
As members
of families with a cancer history, at-risk women
typically experience alterations in several areas of
life. Therefore, Lerman and Croyle voice an important
concern regarding the clinical application of this new
genetic technologythe potential adverse emotional
reaction of this population to genetic status results
(14). Not all sequelae to risk notification may be
negative, as disclosure of a noncarrier status can be a
time of great relief (28). However, researchers in this
field agree the amount of evidence to date does not
provide a clear understanding of the psychological impact
of ones mutation carrier status (14, 19, 29). At
present, possible emotional sequelae to the
susceptibility risk notification process remain largely
speculative. Nevertheless, certain psychological sequelae
to genetic test results may be anticipated (14).
Anxiety
may manifest in women found to be mutation carriers and
may take many forms, including hypervigilance, intrusive
thoughts, sleep disturbances, confusion, somatic
symptoms, and worry about the future. Recently, Croyle et
al investigated the short-term psychological responses of
high-risk patients tested for the BRCA1 gene
mutation (29). Results indicated that elevated baseline
levels of generalized anxiety predicted heightened
indexes of notification-related psychological distress.
In comparison with noncarriers, higher levels of general
as well as genetic test-specific distress occurred in
women identified as mutation carriers. The greatest
levels of distress pre- and postnotification manifested
in carriers and noncarriers who never personally
experienced cancer or cancer-related surgery. As
demonstrated, anxiety may be present in noncarriers as
well. Another study reported on a subset of noncarriers
who continued to manifest anxiety 6 weeks
postnotification (30). The distress experienced by these
noncarriers was understandable, especially for those who
had made irreversible life decisions (i.e., prior
prophylactic cancer surgery) based on an inaccurate
assumption of risk. The receipt of genetic status
findings, however, may have resulted in lowered distress
levels for both carriers and noncarriers (29). Croyle et
al documented an approximately 20% decrease in anxiety 2
weeks posttest across both groups, suggesting alleviation
of anxiety due to the provision of carrier status
information.
Lerman and
Croyle also identify guilt as a potential side effect of
genetic testing (14). For carriers, this may reflect
remorse regarding the possible transmission of a mutated
gene to ones offspring. In noncarriers,
survivor guilt may manifest. These
individuals may experience distress by virtue of being
spared while other family members are afflicted.
Depression,
another possible emotional response to notification of
genetic findings, may be exhibited. Lynch and associates
observed depressive symptoms in both carriers and
noncarriers 6 weeks postnotification (30). Lerman et al
reported the preliminary impact of BRCA1 test
notification on depression, functional health status, and
medical decision making for high-risk patients (31).
Contrary to the findings of Lynch et al, carriers in
Lermans study demonstrated no evidence of increases
in depressive symptoms and functional impairment
following disclosure of their test results at the 1-month
follow-up, whereas noncarriers evidenced significant
improvements in psychosocial functioning. Lerman and
colleagues further explored the relation between
psychological distress to BRCA1 genetic test
utilization and posttest depression in a group of
high-risk women (15). These findings suggested that
cancer-specific distress was significantly related to BRCA1
test use. Among individuals identified as gene mutation
carriers, those scoring highest on cancer-specific
distress prenotification exhibited significant increases
in depressive symptoms at 1 month following testing.
Adverse
psychological reactions also may be experienced by
high-risk family members who decline to undergo genetic
testing. Lerman et al recently investigated a sample of
high-risk women and men who elected not to participate in
genetic counseling and screening after they discovered
the positive carrier status of other family members (28).
Results revealed increases in psychological distress and
depressive symptoms among the decliners at the 1-month
follow-up in comparison with baseline levels. In
addition, heightened cancer-specific stress indexes upon
initial assessment predicted depression among the
decliners on follow-up. These findings suggested that
high-risk family members who decline genetic education
and evaluation might benefit from follow-up services
aimed at reducing psychological sequelae through genetic
counseling.
Because
heightened levels of psychological distress may manifest
in some at-risk individuals, and further alterations in
psychological functioning may occur after notification of
a positive carrier status, Kash emphatically states that
psychological assessment must be amalgamated into the
genetic evaluation and notification process (20). If a
woman has a familial cancer history, it is important to
determine its impact on her coping ability, role
functioning, and psychological distress. For a woman
already experiencing heightened distress levels, it might
be in her best interest to postpone testing until she is
able to handle the results. Additional stressors at the
time of testing may also preclude her ability to manage
news of positive test results successfully at that date.
Kash believes health care professionals must remain
sensitive to the psychological status of those being
screened throughout all stages of the risk notification
process, and they must ensure that adequate psychological
resources are available for referral as needed (20).
PSYCHOLOGICALLY
BASED NOTIFICATION PROTOCOLS NEEDED
Given that
psychological processes permeate the risk notification
process for breast and ovarian cancer susceptibility
testing, the behavioral sciences could provide the
necessary expertise to address the psychological and
emotional impact of this process on the individuals
involved. Historically, patient education has been the
method of anticipated behavior change used in other
health risk assessment settings. Many times, knowledge
has not translated into automatic behavior change,
regardless of risk level. Patient education alone,
although important, is likely to be ineffective in this
setting against the central concerns of reducing
psychological distress and increasing adherence to
surveillance behaviors for breast and ovarian cancer.
Because
the recent commercial availability of breast cancer
genetic screening is expected to generate a great demand
for these services, it is imperative that adequate
protocols be created to facilitate this technologys
transition to standard of care in medical practice. A
need for psychologically based notification protocols is
acknowledged, including psychological preparation for
genetic testing (14, 20). As previously detailed, testing
for cancer predisposition genes involves complex
psychosocial aspects. Therefore, education and counseling
related to this process are essential to fully inform
those undergoing presymptomatic testing of the potential
risks, limitations, and benefits (16). In addition,
high-risk women often fail to adhere to recommended
breast cancer surveillance practices. Because compliance
with breast cancer screening behaviors is important for
this at-risk population, the genetic evaluation process
should include an educational component aimed at
promoting surveillance behaviors (14). Kash and
associates advocate a psychoeducational group
intervention approach to the risk notification process
(21). Further, Mark and McGowan endorse uniting health
care professionals from fields such as genetics,
oncology, and psychology to provide services as part of a
standard cancer risk assessment program (32).
The
components recommended by these previous investigators
will be integrated into a pilot study for women
participating in the Baylor-Charles A. Sammons Cancer
CenterTexas Oncology, PA, Breast Cancer Risk
Evaluation Program. Participants will include patients
possessing a familial or personal history of breast or
ovarian cancer. These patients will receive genetic
counseling, with genetic testing being offered to
patients meeting Registry guidelines for these services.
Participants will be followed longitudinally for
approximately 1 year. Psychosocial questionnaires will be
administered at critical points in the risk notification
process and will include the Hopkins Symptom Checklist;
the Coping Responses Inventory; the Impact of Event
Scale; the Quality of Life, Enjoyment, and Satisfaction
Questionnaire; the Social Support Questionnaire; the
Multidimensional Health Locus of Control; and the Family
Environment Scale. Comparisons of these measures will be
made between women who are found to be mutation carriers,
women who are noncarriers, and a control group. Those
identified as BRCA1 or BRCA2 genetic
mutation carriers will be invited to participate in a
6-week psychoeducational group intervention. The women
who participate may benefit from this group intervention,
as it will provide them with education, skills training,
and group support after risk notification. Overall, the
investigation will expand our understanding of the
characteristics of this high-risk population. Health care
protocols may then be developed and implemented to
provide the best possible quality of care to women
throughout the genetic screening process.
CONCLUSIONS
Genetic
screening for breast-ovarian cancer predisposition genes
has recently emerged on our medical landscape. Positive
aspects of this new technology include the identification
of those having a significantly increased risk of
developing breast or ovarian cancer, the capability to
more actively practice preventive health behaviors that
may help avert cancer onset, and the ability to intensify
screening efforts that may allow for earlier diagnosis in
these individuals, resulting in a decrease in related
morbidity and mortality. Continuing to monitor these
patients may lead to advances in cancer treatments or
cures.
Because
genetic testing for breast cancer susceptibility genes is
relatively new, there has been limited opportunity to
address important ramifications connected with the risk
notification process. Among the most prominent concerns
are the potential psychological and social sequelae that
participants may experience postnotification. Harboring a
genetic mutation and anticipating the possibility of
developing a life-threatening disease may create
psychological consequences, such as fear, anxiety, guilt,
and depression, for those being screened and their family
members. Mutation carriers may be vulnerable to
discrimination, such as the loss of insurance or
employment, as a result of their altered risk status.
Despite
the current paucity of evidence regarding the
ramifications of the breast cancer genetic screening
process, genetic susceptibility testing has entered the
commercial marketplace. Market pressures felt elsewhere
in health careto provide services in a more
streamlined, profit-sensitive mannerappear, at
first glance, to be contrary to the need for greater
services to adequately assist the population of
individuals who will participate in this screening. The
provision of intervention programs and skills training
(e.g., coping and problem solving) could be done in a
relatively cost-efficient manner and could more
effectively counter negative psychological and emotional
sequelae of this process. Benefits would be seen more
immediately in the improved quality of life for the
patients involved, whereas reduced impact of these
diseases on our health care system would be seen in the
long run. Without the understanding of and attention to
psychological issues in this process, the potential for
genetic susceptibility testing to decrease morbidity and
mortality may go unrealized.
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