Critiquing a Breast Cancer Study

This assignment critiques a research study investigating the impact of tamoxifen on breast cancer prevention. The critique focuses on the study's methodology, particularly its reliance on case-control trials susceptible to selection bias and limited ability to determine absolute risk. Furthermore, the analysis points out shortcomings in data analysis techniques and the lack of clarity regarding long-term effectiveness of tamoxifen.

PROTOCOL STRATEGY

TABLE OF CONTENTS
Research Question and its importance.............................................................................................1
Keywords and Combination............................................................................................................2
Search Strategy................................................................................................................................3
Results..............................................................................................................................................4
Table of Articles..........................................................................................................................5
Discussion........................................................................................................................................7
References........................................................................................................................................9

RESEARCH QUESTION AND ITS IMPORTANCE
P
P stands for population. In the present research study, women with history of breast
cancer are being selected as the major population with the age group of 35-50. According to the
case, Mrs Jones is a 45 year old woman who has been treated for breast cancer and who is also
provided tamoxifen for 5 years. However, she did not take medicines for the prescribed time;
hence the health problem increased accordingly.
I
I stands for intervention and in the present research study, the intervention which is
selected is Tamoxifen. This has been selected for the purpose of minimizing the chances of
recurrence of breast cancer in women. Tamoxifen is the only hormonal therapy that is approved
for women who have DCIS and at the same time it also reduces a woman’s risk of developing
breast cancer. It is also a selective estrogen receptor modulator which helps in treating women
having breast cancer.
C
C stands for comparison; however this is not available for the present research.
O
O stands for outcomes; hence the research procedure is about preventing recurrence of
breast cancer in women. In terms of getting suitable outcomes, several articles will be researched
so as to specify the utility of Tamoxifen in minimizing issues related to breast cancer. In order to
get better outcomes, researcher has been emphasizing on varied research articles and journals
which depicts the importance of Tamoxifen in dealing with issues of breast cancer.
Research question
 Does Tamoxifen prevents the recurrence of cancer in women with a history of breast
cancer?
In the present research study, data has been included about Tamoxifen which is given to
women to prevent the recurrence of breast cancer. Women with breast cancer usually take
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tamoxifen for 10 years as a source of primary treatment which also leads to reduction of breast
cancer recurrences and deaths. This drug is usually provided for around 5 years after consulting
the doctors. The stated research question is important because it aims to describe the contribution
of tamoxifen in preventing the recurrence of breast cancer.
The present research study holds more importance for clinical practice as this can aid in
depicting how nursing practices can be improved for women experiencing breast cancer. The
present research is significant since it showcases the utility of Tamoxifen in minimizing the
possibilities of recurrence of breast cancer (Johansson 2016 p. 97–108). At the same time, the
research study seems to be beneficial since it aids in knowing all the aspects which are related to
breast cancer and which leads to diverse health impacts on women. In the same way, the study
seems to be beneficial because it describes about the Tamoxifen and how it helps women to
reduce the chances of further complications under breast cancer. Moreover, in this context it can
also be said that for women, proper therapies and treatment in required at the early stages in
breast cancer so that different health problems can be avoided accordingly.
Along with the same the content placed in the present research study seems to be useful
for promoting education regarding issues of breast cancer in women. Breast cancer is the major
issue that is prevailing in women; however most of the women still do not analyse the issue in
the initial stage (Jahanzeb 2007 p.1535-47). Therefore, the present research study seems to be
beneficial in informing people about strategies and therapies that are useful for treating people
with breast cancer. In addition to this, focus has also been laid on the education which needs to
be promoted for the purpose of reducing the number of cases of breast cancer.
KEYWORDS AND COMBINATION
P I C O
Women suffering
from breast cancer
Tamoxifen Reappearance of
breast cancer
Women with history
of breast cancer
Recurrence
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Under Boolean Operators, two main key words are being used such as ‘OR’ and ‘AND’
to enhance the scope of the research. For instance- search terms are being used through adding
AND so that specific studies about breast cancer and Tamoxifen can be researched. Further,
‘OR’ has been used so as to collect data about the specific research work. With the help of such
key terms, information about the subject matter can be identified and at the same time it can also
enhance the value of researching. With the help of Boolean operators, extensive research is
carried out and this has also helped in searching appropriate research articles. In this respect
women suffering from breast cancer are being ascertained as the major population and according
to the specific problem statement, research articles are being reviewed.
SEARCH STRATEGY
On the basis of generalized concept, search strategy is considered as a way of defining
diverse terms for the purpose of conducting the database. It shows how different terms are used
to get best results for the study. It improves the level of understanding; hence it is being selected
in the research work (Dube 2016 p.158). Therefore, multiple databases are being included in the
research work. At the same time, electronic data search is also used in the study wherein diverse
keywords are utilized to get data about the subject matter.
Database selected
Database selected Description
The Cochrane Library In the present research study, The Cochrane
Library has been selected because it includes
systematic review about medical research. On
the basis of bibliographic database, several
studies are being accessed (Mikkonen 2016
p.173-187).
BioMed Central It is a profit scientific publisher that is
specialised in open access journal publication.
It is selected because it aids in producing the
BMC journal sites which includes fields of
biology and medicine.
PsycINFO9.7 It is the most important database which
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comprises summary of literature in the field
of medicine (Lowe 2016 p.43).
Inclusion and Exclusion criteria
There are two basic criteria that have been selected under inclusion and exclusion
dimension and that are also useful for the purpose of meeting all the dimensions of the research
work. Under inclusion criteria, researcher has taken all those studies which are developed after
2008; at the same time studies made after 2008 have not been included in the research procedure.
Alongside, research done on usefulness of Tamoxifen are being included and rest are excluded
from the research work (Thielen et,al 2016 pp.705-721).
RESULTS
Several articles are being reviewed in the present study which describes the use of
Tamoxifen in minimizing the recurrence of breast cancer in women. This is especially useful for
those who have history of breast cancer. The study developed by Brentnall and et.al. (2007), is
also used in the research work which is a case control study taken from two randomized breast
cancer prevention trials of tamoxifen and raloxifene. In the study, further examination is also
made regarding collection of blood samples from 2 randomised tamoxifen prevention trails.
From the research work, it is being identified that healthy women also have increased risk of
breast cancer because of hereditary. Both the trails were double- blind with women randomised
who are receiving tamoxifen for around 5 years. In the research work, cases were ascertained
during conduction of treatment through clinical visits and also through making questionnaires.
The study has used case control studies which are less costly and less time consuming; therefore
they are considered as advantageous when large number of data is exposed.
Apart from this, researcher has also selected the study done by Hultsch and et.al., (2016),
which makes it clear that Tamoxifen is a standard treatment that aids in reducing breast cancer
mortality by 31%. In the study, it is discussed that 50% of patients have positive cancer and 40%
of patients are acquired with resistance that frequently evolves. In addition to the same, it can
also be said that endocrine therapy is also used that states that aids in reducing breast cancer. In
the research work, 7 Tamoxifen- resistant breast cancer cell line models are used which
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represents the luminal A subtype and which also expresses the HER 2 oncoprotein. In the same
study, drug sensitivity and resistance testing both are conducted so as to ascertain cancer cell
lines which determines the molecular and drug response profiles. These are also specific to
Tamoxifen resistance (Lilyfield 2016 p. A889–A890).
Furthermore, the research conducted by Johansson and et.al., (2016), is also utilized in
the research work wherein it is stated that decreased CYP2D6 activity is directly associated with
lower levels of active Tamoxifen metabolites. In the research study, four randomized breast
cancer prevention trials are conducted along with the dose of Tamoxifen. Apart from this, study
done by Vogel and et.al., (2010), is also included because it shows the detection and treatment of
breast cancer. Thus, in such respect it can be said that Tamoxifen has many well-known benefits
which aids ion treating invasive breast cancer. Moreover, it is also observed as a widely used
technique through which increased risk of endometrial cancer can be ascertained. In the study,
19,747 healthy postmenopausal women were selected who are at the risk of developing breast
cancer.
In the same study, 47 months of follow-up is being conducted and afterwards it is
analysed that there is no difference between the two trails which shows invasive breast cancer
(Vogel 2010). In terms of stating about the methods, it can be said that double blinded trail of
Tamoxifen is carried out with raloxifine for reducing the incidence of breast cancer. In the study,
it is being ascertained that only one woman who was postmenopausal (35 year old) had produced
breast cancer risk; thus she was eligible for further test. At the same time, eligible women were
also randomly assigned to receive 20 mg/d of Tamoxifen plus for around 5 years to maintain the
double blinding of treatment that is assigned to treat the issue of breast cancer.
Table of Articles
Qualitative study
Article Reference
(authors
and
publication
date)
Methodology
(ie:
ethnography,
phenomenology,
)
Population
(how many
participants
, age,
gender,
Issue
(what was
being
studied)
Context
(what was
the study
setting?)
Outcome
(what were the
main findings
in relation to
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disease, etc) the issue?)
1 Brentnall,
R. A. and
et.al., 2016
Through case
control study,
Randomised
trails are carried
out
A total of
1276
women
from both
trials were
initially
selected
It was
carried out
to identify
the
Relationship
of ZNF423
and CTSO
with breast
cancer risk
in two
randomised
tamoxifen
prevention
trials
The main
context of
the study
is to
analyse
how
increased
risk of
breast
cancer can
be
controlled
through
tamoxifen.
It is identified
that there exists
close
relationship
between single-
nucleotide
polymorphisms
and case
control trails of
breast cancer.
Experimental Quantitative study
Article Reference
(authors and
publication
date)
Study
Design
(ie: cohort,
RCT,)
Population
(how many
participants,
age, gender,
disease, etc)
Intervention
(what was
being
implemented)
Comparison
(what was the
intervention
compared
against?)
Outcome
(What are the
consequences
from the
intervention?)
1 Johansson,
H. and
et.al., 2016
Randomized
controlled
trials
Four
randomized
breast
cancer
prevention
trials
based on the
lower levels
of active
tamoxifen
metabolites
Tamoxifen
and
Raloxifen
were
compared
Afterwards,
conducting the
study it is
ascertained
that trials
investigating
tamoxifen
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dose are
adjusted
according to
women’s
hormonal
context and
genotype.
2 Hultsch, S.
and et.al.,
2016
Experimental Molecular
profiles of
the 7 drug
resistant
variants
Systematic
drug testing
and RNA
sequencing of
tamoxifen
resistant
breast cancer
cell lines.
Comparison
was made
with other
drugs in
breast cancer
The study
states that the
cell lines can
be grouped
into
categorised to
prevent the
degree of
cancer after
intake of
tamoxifen.
3 Vogel, G.
V. and
et.al., 2010
RCT 19747
women
Analysis was
conducted
about impacts
of tamoxifen
Randomized,
double-
blinded trial
of tamoxifen
versus
raloxifene
It is analysed
that all the
aspects of the
study are
based on the
intention to
treat principle
that is used to
treat breast
cancer.
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DISCUSSION
Women who have breast cancer are usually exposed to risk of relapse which also leads to
development of primary tumour and which requires radiotherapy. Earlier, varied studies are
being conducted demonstrates the benefits of adjuvant therapy; therefore only a few studies are
being determined which states about impacts of tamoxifen (Lilyfield 2016 p. A889–A890).
However, on the other hand it is also realised that long term exposure of tamoxifen shows
unfavourable risks due to decreasing deficiency and increasing harmful side effects. Nonetheless,
tamoxifen also has carry over effect which provides benefits related to treatment. This needs to
be provided after completing the therapies in the most effective manner.
In several cases of breast cancer, tumour cells have different receptors which also aids to
develop hormone estrogen and it may also depend on estrogen for growth. Hence, women having
such type of cancer are termed as estrogen receptor positive (Hultsch 2016). The main drug that
is used for the purpose of breast cancer at early stages are tamoxifen and aromatase inhibitors.
Out of these drugs, tamoxifen has been used for treating breast cancer; hence in this
consideration number of trails are being conducted to test early stage breast cancer. It is also
analysed that women who undertake hormone replacement therapy during the five years of
tamoxifen had a significant lower advantage as compared to those who do not have. In addition
to the same, it also analyses the known side effects of tamoxifen.
According to the above discussion in health care perspective, breast cancer is a typical
issue that usually arise at the time when women have sedentary life style. The research work also
denotes that adoption of specific method and specific medication aids in preventing the issues
related to breast cancer (Johansson 2016 p. 97–108). In the study, it is also essential for the
practitioners to ensure that along with suitable medication, practitioners’ needs to ensure that the
quantity of Tamoxifen is property provided to the patient. This is also suitable for the purpose of
avoiding different risks and issues which usually prevail in the case of breast cancer.
While using the research articles, it is being ascertained that tamoxifen is considered as
the standard treatment through which issues related to breast cancer can be treated (Jahanzeb
2007 p. 1535-47). However, at the same time, the use of endocrine therapy is also discussed in
the present study which helps in showcasing about the areas through which breast cancer can be
reduced. Afterwards, performing drug sensitivity and resistance testing, it can be said that all the
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cells became tamoxifen- resistant when they have clear sensitivity. There are varied genes and
pathways which are involved in providing avenues that identifies new drug vulnerability for the
tamoxifen resistant cancer cells. In terms of conclusion, it can be said that combination of drug
testing data with RNA sequencing results, there are several potential drugs that aids in planning
about the clinical trials for patients with tamoxifen- resistant breast cancer Cufer (2007).
Henceforth, it can be said that despite of having several improvements in the detection of
breast cancer, the ratio of disease has been increasing on higher extent. Therefore, considering
the same issue, the concept of prevention of breast cancer through tamoxifen seems to be an
interesting aspect. However, on the other hand, tamoxifen does not give positive impacts all the
time, still it is widely used in many cases of breast cancer. Thus, according to the entire
discussion, it can be said that the best research article for the present study is Vogel (2010) which
gives detailed information about the effectiveness of tamoxifen which is useful in treating
women with breast cancer. The methods used were also specific and accurate; hence they are
being considered as useful.
This study is regarded as best because it describes appropriate benefits of tamoxifen in
treating breast cancer at early stages. Women who are taking tamoxifen for around 5 years are
being accessed in the present research study for the purpose of ascertaining the overall benefits
of the medicine. However, the study also states that there were no significant mortality
differences. It has also defined how long term raloxifene retains the effectiveness of tamoxifen in
preventing invasive disease. At the same time, it also helps in identifying how much it contains
toxicity. The study have showed effective results which are important in defining public health
implications. It also clarifies that both raloxifene and tamoxifen are appropriate options in
preventing serious health issues in women.
The study is also best from methodology point of view as it includes randomized trail
between tamoxifen and raloxifene which also reduces the incidence of breast cancer. According
to Thielen and et,al (2016), randomized trials are effective because that helps in identifying all
the methods which can produce suitable outcomes. The study also focused on key secondary
endpoints which includes non-invasive breast cancer and endometrial cancer that usually occurs
together. Hence, combination of all such methods aids in getting appropriate outcomes about the
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aim of the research. Therefore, it is clearly identified in the study that tamoxifen reduces the risk
of contralateral breast cancer in women.
However, on the other hand, the study of Brentnall and et.al. (2007), seems to be worst
because it is based on a case control study from two randomized breast cancer prevention trials.
This was being conducted between raloxifene and tamoxifen. It has also conducted randomized
controlled trails; however still it do not depict feasible responses. In the study, a nested case-
control test was carried out to identity how the prevention of recurrence of breast cancer can be
facilitated. In the study, it was also mentioned that tamoxifen and raloxifene both are useful in
showing reduction in risk of breast cancer (Mikkonen and et,al 2016 pp 173-187).
Further, the study also depicts various inappropriate responses because a combined
analysis has been conducted of 84000 women in 9 trials. The study also states that tamoxifen is
highly useful in eliminating the risk of breast cancer; however it does not depict any sort of
improvement after certain years. In the research study, the section of data analysis was conducted
with genotyping module; therefore the use of critical model is not suitable in depicting exact
responses.
Further, the research work is also worst because it focuses on case control trails which are
also subjected to selection bias. According to Pocock, (2013), case control trails are not
ineffective for rare exposures and information collected on this exposure is sometimes also
regarded as observation bias. Hence, absolute risk cannot be identified in the same area because
it is not suitable in allowing calculation of different incidences (Thielen et,al 2016 pp.705-721).
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REFERENCES
Cufer, T, 2007, Reducing the risk of late recurrence in hormone-responsive breast cancer,
European Society for Medical Oncology.
Pocock, S.J., 2013. Clinical trials: a practical approach. John Wiley & Sons..
Dube and et,al 2016. Predictors of human immunodeficiency virus (HIV) infection in primary
care: a systematic review protocol. Systematic Reviews, 5(1), p.158.
Hultsch, S and et,al 2016, Abstract 2935: Systematic drug testing and RNA-sequencing of
tamoxifen resistant breast cancer cell lines, Cancer Research.
Brentnall, R. A. and et.al., 2016, Relationship of ZNF423 and CTSO with breast cancer risk in
tworandomised tamoxifen prevention trials, Breast Cancer Res Treat, 158: pp.591–596.
Johansson, H, 2016, A pooled analysis of CYP2D6 genotype in breast cancer prevention trials of
low-dose tamoxifen, Breast Cancer Research and Treatment, 159 Issue 1, pp, 97–108.
Lilyfield, O, 2016, Tamoxifen for the Primary Prevention of Breast Cancer: New Life for an Old
Drug, 19 Issue7, pp, A889–A890.
Lowe, S S and et,al 2016. Physical activity in advanced cancer patients: a systematic review
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Mikkonen, K and et,al 2016. Culturally and linguistically diverse healthcare students’
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studies, International journal of nursing studies, 54, pp.173-187.
Thielen, F W and et,al 2016. How to prepare a systematic review of economic evaluations for
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2/3), Expert Review of Pharmacoeconomics & Outcomes Research. 16(6). pp.705-721.
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Prevention Research.
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