Extended Abstract
1. Introduction
According to the American Cancer Society (ACS), there is no precise definition of how childhood cancers separate from cancer in adolescents or the exact time that a person with cancer is considered an adult; however for statistical purposes, cancer in adolescents is often referred to people aged 15-19 years. About 5,000 adolescents (15-19 years old) in the United States are annually diagnosed with cancer, and about 600 adolescents die from cancer yearly. 
Cancer causes about 5% of deaths and is the fourth cause of death in this age group after accidents, suicide, and murder. Psychological factors play an important role in the development of cancer and sustainability and outcomes of the disease treatment. Patients' expectations for illness and positive or negative attitudes toward illness and death affect their mortality rates, compliance rates, medical prescriptions, hospitalization, and recovery rates. 
Attitude towards death refers to the total cognitive, emotional, and behavioral responses of a person to death. These attitudes can be positive or negative; negative attitudes about death include fear of death or avoidance of death. However, positive attitudes toward death include coping with death and accepting it. Coping with death consists of a set of cognitive, behavioral, and emotional responses to death before their own and others’ death. 
It is specified that coping with death is negatively correlated with the indicators of fear of death. Therefore, not only the identification of the attitude of people with cancer to death is important, but it is also necessary to identify the factors affecting death and its attitudes, such as attachment styles, emotional suppression, and anxiety sensitivity. One of the variables that play a fundamental role in the attitude towards death is the quality of the parent-child relationship, which forms the basis of the attachment style. 
Attachment is the deep emotional bond that we establish with special people in our lives so that when we interact with them, we feel excited and relaxed, and when it comes to stress, feel relaxed about having them next to us. Attachment is vital for children; because as the child explores the surrounding world and faces unpredictable things, it gives them a sense of security and tranquility. 
The attachment has different styles and is generally divided into two categories of secure and insecure. Evidence suggests that adolescents and adults enjoy secure-sharing patterns with greater satisfaction and long-standing relationships with others; while, insecure attachment is linked with emotional distances from others, loneliness, and hostility. Attachment contributes to the formation of the personality and traits; therefore, it is closely related to the way a person with cancer copes with his illness and follows the medical orders regimen. Insecure attachment imposes more stress on the person. When an adolescent with insecure attachment faces conditions like cancer, he is very disturbed and may have a negative attitude toward the future and death. 
The lack of experiencing emotions, shedding feelings within the self, the lack of expressing emotions, and ultimately emotional repression can negatively affect the attitude to death. Emotional repression is a defense mechanism that reduces emotional pain; however, fails to help to resolve the real issue. 
The repression of painful emotions by reinterpreting events makes us less aware of these unplanned things that we are incapable of changing and thinking about. Previous research has explored personality types and related illnesses in the field of health psychology. They concluded that cancer-prone persons tend to be depressed, provide desperate feedbacks, and fail to express emotions, especially the negative ones. This pattern forms a particular personality type, called the C personality. The findings suggested a close relationship between emotion suppression, which is one of the most essential characteristics of the C personality type and cancer. 

Anxiety and its related problems, like high anxiety sensitivity, can also affect the death attitude. Anxiety sensitivity is a cognitive structure that was first considered by Reis and McLenn (1985). Anxiety sensitivity is practically a fear of anxiety and emotion associated with arousal. Individuals with high anxiety levels perceive stressful situations with extreme feelings and thoughts. Moreover, in extreme cases, they are prepared to respond to intense anxiety responses to stressful situations, where people with high anxiety sensitivity often react negatively to anxiety symptoms. However, people with low anxiety sensitivity, although they may perceive symptoms as unpleasant, do not consider them as a threat. Cancer is a threat, and many people are anxious to respond to it. In addition, the anxiety sensitivity level in coping with cancer and the attitude to death plays an important role in this area. 
The role of attachment styles on death attitude is unclear in adolescence. Additionally, the role of emotional repression and anxiety sensitivity in the relationship between attachment styles and death attitude is undetermined. Thus, this research investigated the impact of these variables on the death attitude of adolescents with cancer in the form of a hypothesized model (Figure 1). 
2. Methods
This was a fundamental and descriptive-correlational study. The study population consisted of adolescents with cancer in Isfahan City, Iran. They were selected by convenience sampling method (N=150). To collect data, Hazan and Shaver Attachment Styles in Adults Inventory, Wittenberg's Emotional Suppression Questionnaire Floyd Anxiety Sensitivity (AS) Inventory, and Wong Death Attitude Inventory were used. The obtained data were analyzed by Structural Equation Modeling (SEM). 
3. Results
The achieved results indicated that attachment styles have a significant direct relationship with the attitude toward death in adolescents with cancer (β=0. 40). Furthermore, attachment styles, through mediating role of emotional suppression and anxiety sensitivity, have significant relationships with the attitude toward death in adolescents with cancer. 
4. Discussion
The study findings suggested that attachment, as an exogenous variable, affects the death attitude. In other words, the attentive care provided by the parents to the children and the appropriate response to their needs forms a secure attachment leading to schemas in them. Moreover, the world of creation, being and non-being, is a safe place. Such schema could influence the children's lives in the coming years (from adolescence to adulthood) and develops a sense of deep psychological security in person. Thus, even when faced with unpleasant and life-threatening events, including cancer and death, they fail to receive safety from the person. Because they consider death as a temporary separation from his security base (parent or caretaker). In addition, as a result of this security, the person is not afraid of death and has a positive view of it and accepts it. In people with insecure attachment, the opposite case happens. 
The findings revealed that attachment styles, through the mediating role of emotional repression, have significant relationships with the death attitude in adolescents with cancer. In other words, an insecure attachment style (i. e. perceiving the world an unsafe) affects the subsequent growth of the individual; because the child is afraid of separating from the security base (parent or caregiver). As a result, there is no chance to discover a new environment and develop more social relationships and skills. 
Therefore, he or she is deprived of learning adaptive strategies of emotion regulation, like emotional expression in life events. Instead, they use conflicting strategies, like emotional repression. Because of this repression and erroneous emotional regulation, one avoids coping with issues, like death, which creates a negative emotion or represses these issues and excitement in them. Accordingly, repressing the emotions and not having to cope with such issues gives them the chance to think about the subject to normalize it. As a result, they either avoid these issues or are afraid of thinking about them. In people with secure attachment styles, the opposite case happens. 
The findings suggested that attachment styles, through the mediating role of anxiety sensitivity have significant relationships with the death attitude in adolescents with cancer. 
Insecure attachment leads to mental insecurity in the child. Following this issue, the person interacts with the environment and does not separate from the security database. Therefore, he is deprived of learning various skills or lacks these skills. The lack of skills in tedium over time impacts child growth. These effects include cognitive problems (cognitive errors, attention bias, the formation of negative thoughts and irrational beliefs, etc. ), emotional shaking and emotional instability, or even impaired autonomic nervous system (sympathetic and parasympathetic) as a result of hormonal changes. Accordingly, the anxiety system of the person associated with these problems is disturbed, and the person generates anxiety problems, such as anxiety disorders, high anxiety sensitivity, and so on. 
Along with the high sensitivity of anxiety, stressful events, like cancer and its unknown outcome (therapeutic or death) occur with many biopsychological symptoms. Because of the high anxiety sensitivity, he takes the symptoms as threats and magnifies them. As a result, to prevent the occurrence of these symptoms, the person attempts to deny the truth of cancer and the resulting death. As a result, he does not face cancer or death in general, and normalization does not occur. The final result is the tragedy of having to die and having a negative attitude toward it (fear and avoidance of death). 
In conclusion, attachment styles, emotional suppression, and anxiety sensitivity are essential determinants of attitude toward death in adolescents with cancer. Moreover, the assessed model can explain the attitude toward death in these individuals. 
Ethical Considerations
Compliance with ethical guidelines
An  informed consent was obtained from the participants after explaining the research Objectives and method; They were also free to leave the study at any time and were assured of the confidentiality of their information. 
Funding
This research received no specific grant from funding agencies in the public, commercial, or not-for-profit sectors.  
Authors contributions
Conceptualization, methodology, initial draft preparation by all authors; investigation, supervision and project administration by Mojtaba Ahmadi Farsani and Rasool Heshmati;  resources, editing and review by Mojtaba Ahmadi Farsani.
Conflicts of interest
The authors declared no conflicts of interest. 
Acknowledgements
the authors would like to thank all the participants as well as the management and personnel of the ALA Cancer Prevention and Control Center and Omid hospital of Isfahan for their cooperation in this research.