Gender Differences in Lung Cancer

This assignment examines the influence of gender on lung cancer, specifically focusing on mutational burden and its correlation with survival rates. It analyzes how mutational difficulty differs between genders and its significance in diagnosis. The research aims to highlight the disparities in clinical outcomes based on gender in lung adenocarcinoma.

Running head: ASSOCIATION BETWEEN GENDER AND LUNG CANCER
Association between Gender and Lung Cancer Prevalence
Name of Student
Institution affiliation

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Introduction
Vavalà, Mariniello, Reale and Novello (2016), opined that in early 20th century, less than
a thousand cases of lung cancer were discovered. However, continued use of tobacco especially
in men caused an increase in lung cancer cases. Smoking makes it the leading cause of cancer in
both genders in developed nations. Vavala and colleagues suggest that the higher prevalence of
lung cancer in non-smoking women in comparison to non-smoking men in due to their different
biological attributes.
Currently, smoking of cigarettes makes up over ninety percent of lung cancer cases in
men and between seventy to eighty-five percent of women in the United States and European
countries (Torre, Bray, Siegel et al., 2015). Marshall and Christiani (2013) found that roughly
twenty percent of women suffering from lung cancer have never used cigarettes and they noted
that six percent of women have a risk of developing lung cancer in their lives irrespective of
whether they are smokers or non-smokers suggesting that lung cancer develops differently
between non-smoking women than non-smoking men.
Secretan, Straif and Baan et al. (2009) study revealed that roughly twenty percent of
cancer deaths globally are due to lung cancer. They found that due to its high rate of overall
fatality (overall mortality ratio of prevalence of 87%) and comparable lack of variance in
different global regions, the regional prevalence rate of mortality used the same prevalence data.
In the study they revealed that lung cancer was more prevalent in Australia and New Zealand
with men having a higher lung cancer death rate at 43 and women at fifteen. In Europe, mortality
rate stood at forty while women it was eleven. In America mortality rate for men was fifteen,
females was two. Examining Asian countries, lung cancer death rate was fourteen for males
while women were slightly above five. China had the highest rate (eighteen for every one
hundred thousand) a rate higher than some European countries regardless of a considerably low
smoking rate for women in China. They attributed this high prevalence rate of lung cancer in
women of China due to second hand smoke and poor ventilation of houses where they use coal
for cooking and heating.
Torre et al. (2015) postulated that lung cancer related deaths would increase from over
one million case and double to close to three million by 2035in both men and women. They
predicted the increase could be progressive globally but on different proportions with Europe

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recording the lowest at thirty-seven percent. In western Pacific areas at 97%, America at 91%
and Asia at ninety-five percent. The eastern Mediterranean and Africa would experience an
increase of over one hundred percent within the same period.
According to Society for Women’s Health Research (2016), lung cancer is the leading
killer of American women. In a study done in America, only 1% of women identified lung
cancer as a major concern. The important point is that prevalence of lung cancer is headed in
different directions among men and women. In the last three decades, lung cancer cases in men
have gone below thirty percent while on the other hand increased by ninety-six percent in
women. This is because the rate of smoking in men increased earlier in men than in women. For
women, the rate of smoking was much lower in the seventies until later when cigarette
companies started targeting women in their marketing campaigns. These campaigns caused the
increase in smoking for women. More importantly, however, it should be noted that lung cancer
could affect anyone. In deed roughly sixty percent of lung cancer cases are from people who
have either never smoked or have quit. This includes those exposed to second hand smoke and
other air pollutants.
Society for Women’s Health Research suggests that the major variance between male and
female prevalence of lung cancer has little to do with biology but more on awareness and
attitude. Inasmuch as more women are dying due to lung cancer very few women identify the
disease as a health risk. The society of women notes that in 1987 lung cancer overtook breast
cancer as the leading cause of death due to cancer in the United States alone. It was estimated in
2016 that twenty-five percent of cancer deaths in women would be from lung cancer.
Additionally, almost fifty percent of women diagnosed with lung cancer would not live for more
than a year.
Kiyohara and Ohno (2010) are of the view that in terms of numbers more males develop
and die from lung cancer. However, this does not imply that they are more vulnerable. Research
on molecular structures of lung cancer has shown that developing cancer in men and women to
identify whether women were more prone than men to lung cancer had positive results. The
general view from researchers is that although men have a higher death rate due to lung cancer
than women, women are at greater risk to develop it. The higher prevalence rate in men is
attributable to higher regularity of smoking (Ibid).

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The final project will have a number of variables. This will include the independent
variable (gender) and the dependent variable (lung cancer stage). This study will therefore
examine the association between gender and lung cancer.
Statement of the Problem
This paper set out to determine the association between gender (male and female) and
lung cancer prevalence (lung cancer stage). Past research postulate that distinction between men
and women in terms of clinical manifestation and biology of lung cancer. Most studies are of the
view that lung cancer ought to be viewed as a separate entity in females whereby
adenocarcinoma is the most prevalent histological subtype and diagnosis where treatment is
explained as different. In spite of these observations, no gender-specific prognostic
advancements are available in recent research. Knowledge improvement of lung cancer in
women allow identification of particular genetic modification or even hormonal set up that could
be aimed at therapeutic and enhancement of gender-based studies on lung cancer
This study therefore strives to unearth the association or relationship between gender and
the prevalence of lung cancer. The aim will be to generate data and suggest recommendations for
interventions in order to reduce morbidity and mortality of the disease and subsequently reduce
the economic cost of cancer.
The researcher question therefore will be: Is there an association between gender and
lung cancer prevalence? The independent variable for this study will be gender (male and
female) while the dependent variable will be lung cancer stage. The independent variable
(gender) is a dichotomous variable where each category does not affect the other. The dependent
variable is an ordinal variable where the number represents a rank of some sort.
Research Hypothesis
The research hypothesis for the study will be as below
H0 : There is no association between gender and lung cancer prevalence (null hypothesis)
HA : There is an association between gender and lung cancer prevalence (alternative
hypothesis)

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Statistical Tests
This study will seek to determine the association between gender and lung cancer from
the sample data. The null hypothesis will be the difference between the expected values and the
observed values could be zero. Put another way, there is no difference between prevalence rates
of lung cancer in terms of gender. The appropriate statistical test for the independent and
dependent variable therefore was the chi-square test for independence. This was done by testing
whether there was any significant relationship between gender and prevalence rate of lung
cancer. Chi-square test is a non-parametric test that does not have rigid assumptions to the type
of population under review. To perform the chi-square test of independence, the researcher will
make some assumptions. That there is some form of randomization of the sampled data, the
sample size is adequate and cell count is adequate.
Inferential Statistics
Having determined the descriptive statistics in relation to demographic data and the
prevalence rate of lung cancer, the researcher,will seek to investigate whether there was an
association between gender and prevalence rate of lung cancer.The statistical significance of less
than .05 alpha level will suggest that the differences between the observed values and the
expected values is not due to sampling errors of chance. This will be done by testing whether
there was any significant relationship between gender and prevalence rate of cancer. Inferential
statistics (Chi Square (2) will be used in making deduction and generalizations about the whole
population using the sample data.

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Annotated Bibliography
1. Chen et al (2015). Contrasting male and female trends in tobacco-attributed mortality in
China: evidence from successive nationwide prospective cohort studies. Lancet 2015; 386:
1447–56
Chen et al (2015) did a study on contrasting male and female trends in tobacco-attributed
mortality in China. They did two national studies fifteen years apart and recruited twenty-two
thousand men aged 40-79 years in the first study and two hundred and ten thousand men
including 300,000 women aged 35-74 years in the second study. They utilized Cox regression
analysis that achieved gender-specific adjusted mortality rate ratios (RRs) by comparison of
smokers including those who had quit smoking on the one hand and those who had never
smoked on the other. Findings revealed that over sixty percent of the males smoked. There was
no significant relationship between age of the male smokers and prevalence of lung cancer. The
study suggested that smoking is likely to cause one in five men deaths in China in the 2010s.
They attributed this observation to rising smoking proportions of men though at a low rate and
decrease in women. This study will assist to determine the connection between smoking and
prevalence of lung cancer.
2. Moura, M. A., Bergmann, A., Aguiar, S. S., & Thuler, L. C. (2014). The magnitude of the
association and the risk of developing cancer in Brazil: a multicenter study. BMJ Open,4 (2).
doi:10.1136/bmjopen-2013-003736
Moura et al (2014) in their Brazilian study on the magnitude of the association between smoking
and the risk of developing cancer while researching among other cancers the risk of development
of lung cancer according to gender revealed a bigger risk for women associated with cigarette
smoking. Secondary data was used as an observatory instrument derived from the Brazilian
Cancer Hospital Registries (CHR). This study will be used for comparison with the present study
outcomes to determine whether similar results will be achieved.
3. Paris, C., Clement-Duchene, C., Vignaud, J., Gislard, A., Stoufflet, A., Bertrand, O., . . .
Hainaut, P. (2010). Relationships between lung adenocarcinoma and gender, age, smoking and
occupational risk factors: A case–case study. Lung Cancer, 68(2), 146-153.
doi:10.1016/j.lungcan.2009.06.007

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Paris, et al. (2010) used unconditional logistic regressions (ULRs) to determine the relationships
between among other factors gender and lung cancer. The objective of the study was to
investigate the likely correlation between among other factors gender and lung cancer. The study
was done using data derived from two French Universities hospitals from 1996 to 2006 of
personal interviews with patients attending the two hospitals. The logistic regression model no
association between gender and lung cancer apart from a negative correlation with duration of
smoking. The findings of this study will assist in assessing whether other occupation factors such
may be associated with lung cancer prevalence in the present study and whether gender in the
current study will have significant association lung cancer prevalence.
4. Xiao, D., Pan, H., Li, F., Wu, K., Zhang, X., & He, J. (2016). Analysis of ultra-deep targeted
sequencing reveals mutation burden is associated with gender and clinical outcome in lung
adenocarcinoma. Oncotarget,7(16), 22857-22864. doi:10.18632/oncotarget.8213
Xiao, et al. (2016) in their study “ Analysis of ultra-deep targeted sequencing reveals mutation
burden is associated with gender and clinical outcome in lung adenocarcinoma” evaluated the
clinical importance of the burden of mutation in lung cancer and revealed that male tumors
exhibited statistically bigger load of genetic differences than females (Male median 3; range 0–
34) vs female median = 2:;0–24), male to female ratio = 1.636, 95% CI = 1.343–1.992). They
used the Kaplan-Meier survival analysis that revealed that the bigger burden of genetic
differences was correlated with overall survival. In addition, analysis revealed mutational
difficulty was an independent diagnostic factor for the patients. Combining the two techniques
revealed disparities between gender on mutational difficulty and their diagnostic importance in
lung cancer. The gender differences in mutational difficulty revealed in this study will aid the
present study to research further on the clinical results between genders in lung adenocarcinoma.

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References
Chen et al (2015). Contrasting male and female trends in tobacco-attributed mortality in China:
evidence from successive nationwide prospective cohort studies. Lancet 2015; 386:
1447–56
Giovino GA. Epidemiology of tobacco use in the United States. Oncogene 2002; 21: 7326-40.
Kioyora, C., & Ohno, Y. (2010). Sex differences in lung cancer susceptibility: A review. Gender
Medicine.7 (5), 381-401. doi:10.1016/j.genm.2010.10.002
Marshall A.L, Christiani DC. Genetic susceptibility to lung cancer--light at the end of the tunnel?
Carcinogenesis 2013; 34(3): 487-502.
Moura, M. A., Bergmann, A., Aguiar, S. S., & Thuler, L. C. (2014). The magnitude of the
association and the risk of developing cancer in Brazil: a multicenter study. BMJ Open,4
(2). doi:10.1136/bmjopen-2013-003736
Paris, C., Clement-Duchene, C., Vignaud, J., Gislard, A., Stoufflet, A., Bertrand, O., Hainaut, P.
(2010). Relationships between lung adenocarcinoma and gender, age, smoking and
occupational risk factors: A case–case study. Lung Cancer, 68(2), 146-153.
doi:10.1016/j.lungcan.2009.06.007
Society for Women’s Health Research. (2016, May 24). Does Lung Cancer Have a Gender Bias?
[Web log Post]. Retrieved September 27,201, from
http://www.huffingtonpost.com/society-for-womens-health-research/does-lung-cancer-
have-a-gender-bias_b_10116138.html
Torre L A, Bray F, Siegel R.L, et al. (2015).Global cancer statistics 2012. CA Cancer J Clin;
65(2): 87-108.
Vavalà, T., Mariniello, A., Reale, M. L., & Novello, S. (2016). Gender differences in lung
cancer. Ital J Gender-Specific Med, 2(3), 99-109.
Xiao, D., Pan, H., Li, F., Wu, K., Zhang, X., & He, J. (2016). Analysis of ultra-deep targeted
sequencing reveals mutation burden is associated with gender and clinical outcome in
lung adenocarcinoma. Oncotarget,7(16), 22857-22864. doi:10.18632/oncotarget.8213

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Appendix
Data Dictionary