Prostate cancer screening: what do men know, think and do about their risk? exploring the opinions of men in an urban area in Lagos State, Nigeria: a mixed methods survey

Introduction Prostate cancer (PCa) is the leading cause of cancer-related deaths in men aged 40 years and older. Incidence and mortality rates are higher in African men. PCa is amenable to early detection by screening which can prevent and reduce cancer deaths. Late-stage presentation and diagnosis often occur due to poor screening practices. This study assessed the knowledge, attitude, prevalence and barriers towards PCa screening among males in an urban area in Nigeria using a mixed method approach. Methods This cross-sectional descriptive study used quantitative and qualitative methods among men aged 40 years and older. A pretested structured questionnaire was used to interview 344 respondents through multi-stage sampling. Additionally, two focus group sessions were held using a pre-tested guide. Results Respondents were between 40-89 years with a mean age of 52.8 ± 9.9 years. Majority (54.9%) had poor knowledge of prostate cancer and its screening methods however, 65.7% expressed positive attitudes towards screening. Only 73 (21.2%) had ever been screened. The focus groups showed that respondents expressed a willingness to undergo PCa screening. The main barriers to screening were the fears of a positive result, ignorance and financial constraints. Participants preferred male physicians during digital rectal examinations. Conclusion Respondents showed poor levels of knowledge. They expressed positive attitudes towards screening. However, this was not translated into practice. Public health interventions should educate men about benefits of early detection while addressing fears of positive findings and gender biases during rectal examinations. Efforts at providing low-cost alternatives for PCa screening are needed.


Introduction
Prostate cancer (PCa) is the fourth leading cancer-related cause of death worldwide and the second most common cancer among men; an estimated 1.1 million men worldwide were diagnosed with PCa in 2012, accounting for 15% of the cancers diagnosed in men [1]. The burden of prostate cancer is expected to grow to 1.7 million new cases and 499,000 new deaths by year 2030. Various epidemiological data have supported the high incidence and mortality of this malignancy amongst the blacks [2]. Nigeria lacks a thorough cancer data base so information on PCa incidence are often based on individual reports [3]. In Nigeria, as with many black African countries, PCa is the most common cancer among males; in 2014, the World Health Organization (WHO) reported 30,400 cancer-related deaths in Nigeria and 31.7% of these deaths were as a result of prostate cancer [4]. In contrast to high-income countries, where mortality rate is low as a result of routine screening leading to early detection, majority of the cases in low and middle-income countries like Nigeria are diagnosed among symptomatic men at advanced stages with attendant higher mortality rates [5]. Assessing the knowledge, practice and uptake of screening methods among at-risk men in the community for PCa is a critical first step towards improving screening practices, early detection and treatment [6]. Prostate cancer screening is an attempt to diagnose PCa in asymptomatic men.
This includes the measurement of serum prostate specific antigen (PSA) and digital rectal examinations (DRE). Despite the increased awareness of prostate cancer screening globally, the uptake has remained low especially in sub-Saharan African [6]. Qualitative methods of data collection are relevant in exploring knowledge and barriers to health-seeking practices in target populations [7]. Few studies have used qualitative methods to explore the knowledge, attitude and prostate cancer screening practices among males in countries where the burden of PCa is greatest [8]. We therefore used a mixed methods approach to assess the knowledge, attitudes and practices of PCa screening among a group of males in an urban environment in Lagos state.

Study setting, study design and study population
The cross-sectional descriptive study was carried out in Itire-Ikate local government, an urban area, in Lagos State, South-western region in Nigeria. The indigenes are predominantly of Yoruba ethnicity and are mostly petty traders, motorcycle riders, bus drivers and politicians. Ethical approval for the study was obtained from the Health Research and Ethics Committee of Lagos University Teaching Hospital. It was conducted among adult males aged 40 years and above. Only men who had resided in the community for at least six months and aged 40 years and above were included in the study.

Quantitative data collection
Sample size, sampling method, data collection tools,

techniques and data analysis
For the quantitative aspect of the study, the minimum sample size was calculated for the study using the standard formula for descriptive studies and based on the relevant findings of a previous study [5]. These findings revealed that only 28.4% of participants had ever tested for prostate cancer; this was used to calculate sample size for this study. Considering a confidence level of 95%, an alpha of 0.05 and a precision of 5% and an expected non-response rate of 10%, the final sample size for the study was 344. Respondents were selected using a multistage sampling method in five sequential stages i.e. selection of wards, streets, houses, households and respondents in that order. Quantitative data was collected by trained interviewers using a pre-tested questionnaire adapted from the following tools: The  [9][10][11]. The occupational levels of respondents were classified using the International Standard Classification of Occupations [12].
Participation in the study was voluntary and a written informed consent was obtained prior to data collection.
Quantitative data was entered and analysed using SPSS version 21.0.
Knowledge and attitude scores were computed and graded in the following manner. There were five (5) questions assessing the knowledge of prostate cancer and screening practices. Correct responses awarded one point and incorrect responses awarded zero point. These scores were summed and converted into a percentage scale. Levels of knowledge were categorized as poor (<50%) and good (≥ 50%). Attitude towards prostate cancer screening was assessed on a five-point Likert scale with the most positive response receiving five points and the most negative, one point. These scores were summed and converted into a percentage scale. Respondents with scores less than 50% were classified as having negative attitude, while those with scores of 50% or more had positive attitude. There were nine (9) questions assessing their attitude. Chi-square and ttests were conducted to determine if there was any relationship between the respondents' socio-demographic variables, their knowledge, their attitude and prostate cancer screening. P values of < 0.05 were considered statistically significant.   (Table 5).

Qualitative results
Participants in both group discussions were aged between 41-58 years. Majority (87.5%) of the participants had at least a secondary level of schooling and most were married (81.3%), of Yoruba ethnicity (81.3%) and practiced Christianity (75%).

Understanding of prostate cancer
The participants had some knowledge of cancer and the symptoms of prostatic enlargement: "Prostate cancer, it has to do with one´s urination. I had a friend whose dad died from prostate cancer, overtime he could not help himself so they had to put pipe and over time he died so it is that growth that makes your bladder expand overtime so it can´t contain the urine." (B, 56).
"Prostate cancer, heard of it on Wazobia (an FM radio station); not sure exactly what it is, would like to know more". (I, 47).

Early detection
Majority of the participants said that prostate cancer can be prevented and they felt that orthodox medical practitioners were best at diagnosing prostate cancer; some acknowledged screening as a means of early detection. "I will feel nervous at first but will summon courage cos if anything is found then treatment will proceed; it is better to go than not at all" (J, 45).
"Happy, because for me, prostate cancer starts at an old age and at my age I would love to go if asked; even without anyone asking cos I already have mind to go for the test". (E, 55).

Digital rectal examination (DRE)
The participants´ main concern about a DRE was about the gender of the health practitioner carrying out the procedure; however, the importance of the test could outweigh their concerns about the gender of the practitioner. They stated that they would feel ashamed if a female physician carried out the procedure on them.
"Whatever the doctor instructs me to do, I will do. But if it´s a female doctor, I will feel ashamed but at the end I must do it so that the screening can be carried out. If it´s a male, I won´t be ashamed cos it´s a man like me but if it´s female, I will feel ashamed but I will do it because I have to" (M, 44).
"I will do the test but I must ask for man first. If there´s no man I will manage and do it". (F, 58)

Prostate specific antigen blood test
Their major concern about the PSA was the associated pain of the needle prick and possible swaps in blood samples based on human errors. Otherwise they seemed to be comfortable with this screening method; no cultural or religious issues were raised about the PSA.

History of screening
None of the participants had ever gone for prostate cancer screening.
They attributed this to poor knowledge and attitude towards screening and a lack of awareness for the need of a screening test, due to the absence of symptoms. They also said that they did not know where to go for such a test.

Barriers to screening
There were three prominent barriers: (fear, ignorance and financial constraints) to prostate cancer screening.
"Ignorance is one reason and then some people that know are scared to go cos they feel that when you get the problem then you won´t have the money to cure the problem". (B, 56).
"HIV/AIDS is now free cos now people volunteer themselves for the test so prostate cancer test should be free; the drugs are too expensive to buy so that makes people not to test, that´s why people don´t go. They would rather live with it until they die". (D, 50)

Suggested ways of improving screening rates among men
Majority of the participants in the FGD suggested a focus on the importance of life as a way of convincing people to test for prostate cancer; some said they would only approach persons with whom they had a personal relationship while others would not approach anyone unless they sought their advice. Some believed in leading by example.
"The easy way to convince people is through seminars; we will then be able to pass the message to everyone that may or may not know.
Once you pass the message and let them know the importance, they will now know it´s a matter of life and death. It will be best to tell them how expensive or cheap it is so that way, they can make their own judgment" (D, 50).
"You can´t just tell anyone to go for the test except you come to me as a friend or someone you can 'lick´ your secret to, that´s when the person will tell me. You might see someone and want to advice but then the person will be annoyed with you so I will wait for the person to talk to me about it then I can even follow you for the test". (J, 45) "I will go for the test first before trying to convince someone. If I haven´t done it, I can´t tell someone to do it so if I go first, I can willingly tell someone". (N, 45).

Discussion
A key finding observed from the quantitative and qualitative aspects of this study was that majority of the respondents had never been screened for prostate cancer (73.9%) [13]. This low screening rate was also observed in a similar study in southwest Nigeria where only 10.2% of the respondents had ever been screened for prostate cancer. Similar findings were also observed among men in Ghana where 90% of the respondents had never been screened [14].
Considering the fact that prostate cancer is amenable to early especially those at elevated risk of prostate cancer in a shared decision making [18].
In this study, although screening rates were poor, it was observed that respondents were nevertheless willing to be screened, as slightly more than half of the men who had never been screened (51.7%) indicated an interest in screening within the next year. Positive attitude and willingness to undergo screening have also been reported among men in Ekiti state and in Nsukka which are located in the South-Western and South-Eastern parts of Nigeria respectively [13,15].
The fear of a possibly positive test results was noted as a barrier to future screening in the qualitative aspect of this study. This fear has also been expressed by respondents in previous studies [15,17]. In the study among male employees of the University of Nigeria, more than half of the respondents did not want to be screened because of the fear and anxiety associated with a possible positive result [15].
Lack of adequate knowledge may create fear and anxiety which increases the likelihood that an individual will not access information on prevention [16]. Interestingly, the fear of positive results has been a common finding in cancer screening generally. For instance, in a critical review study on fear, anxiety, worry and breast cancer screening behaviour, it was discovered that women´s primary fears surrounding breast cancer and its screening was the fear of a positive diagnosis, in addition to the fear of pain/discomfort associated with testing [19].
Some men may find the idea of having a digital rectal examination (DRE) uncomfortable. However, clear gender preferences for DRE, in favour of male health practitioners were noted in the study. Several community-based studies have cited DRE as one of the barriers to screening [14,16]. In contrast; the study in University of Nigeria among male employees who may be more educated reported that DRE was not a barrier to screening [15].
A key strength of this study is the fact that it is one of the few studies that has assessed the knowledge, attitudes and screening practices of prostate cancer using both qualitative and quantitative methods.
The findings may however need to be interpreted with some caution as it also has some limitations. Firstly, data was collected by selfreport and is prone to misreporting and recall bias. Secondly, causal inferences cannot be made as the study is cross sectional in nature. main barriers to screening and to promote adequate pre-screening counselling. In addition, research on the psychological and emotional influences of the acceptability of preventive services in the population is also warranted.

Conclusion
This study showed that although the knowledge of prostate cancer screening among the men were poor, they expressed positive attitudes towards screening. Their willingness to go through with the screening was however subject to certain conditions like subsidized costs and a preference for examinations by male physicians.

What is known about this topic
 Prostate cancer is the leading cause of cancer related deaths among African men and the incidence increases with advancing age;  Screening leads to early detection and reduced mortality among men.

What this study adds
 Prostate cancer screening is low among this group of older men. However, opportunities for screening may be welcome as many of them expressed positive attitudes towards screening, particularly if it is free or subsidized;  Pre-screening counselling to address the fears of a possibly positive result might be helpful.

Competing interests
The authors declare no competing interests.  Table 1: social demographic characteristics of the respondents