1. Introduction
The aging of societies has created new challenges, especially in developing countries [1]. Statistical indicators show the fact that as the world's population is aging, the aging process in Iran has begun. According to the census of the Statistics Center of Iran and the studies conducted, the population over 60 years of age in Iran in 2021 has increased by more than 10% [2]. Although aging itself is not a disease, it involves physiological changes that occur over time, but as a result of these changes, the rate of acute and chronic diseases increases [3]. 
Cancer is one of the chronic diseases that increases the risk of developing it as we age [4]. Prostate cancer is the third most common cancer in Iran and the seventh leading cause of cancer death. The highest incidence of this disease is observed in North America and the lowest incidence in Southwest Asia [7]. The standardized age incidence rates of cancer in Iran, Turkey, and North America are 6.11, 40.9, and 97.2 per ten thousand, respectively. The lowest rate in Kerman is about 3.2 per ten thousand people. The low incidence of this cancer in this province is due to the life characteristics of people in this region, lifestyle, and the existence of other diseases and cancers [8]. The most important risk factors for prostate cancer studied in the world are alcohol, addiction, genetics, low consumption of fruits, vegetables, and geographical environment [9]. This study aimed to investigate the effect of two variables of age and Gleason score on changing the status of elderly patients with prostate cancer who have undergone surgery, using a multidisciplinary model.
2. Materials and Methods 
All patients completed a questionnaire including age, medical history, etc. After surgery, for each patient, tests at different times, the amount of PSA antigen and the physician's opinion about the amount of this enzyme were measured and recorded. The collected data included recording the amount of PSA enzyme and its recording time, before and after surgery and at the time of transition between conditions, Gleason score, age, and history of drug use in patients. In this study, individuals were divided into two groups less than and more than seventy years old.
3. Results
The participants of this study are 125 elderly patients with prostate cancer who have undergone surgery and with a mean age of 72.12 (standard deviation 7.32) years. Of these patients, 59 had a Gleason score less than seven, 47 equal to seven, and 21 less than seven. The median time after surgery to local recurrence is 4.5 years (standard deviation 4.35), two years (standard deviation 1.6) to distant recurrence status, and 6.5 years (standard deviation 1.44) from surgery to death. The number of modes considered in Figure 1 and the frequency of the number of transfers are shown in Table 1.

The multidisciplinary model considered for these data is fitted with two variables of age and Gleason score and the effect of these two variables on the probability of transfers is also given in Table 1. Due to the possibility of transfers, people who underwent surgery were 17% more likely to metastasize and accept hormone therapy, and 8.8% more likely to have a local recurrence and receive radiotherapy, and 8% more likely to die. The risk ratio for age and Gleason score and 95% confidence interval are shown in Table 2.


4. Discussion and Conclusion
 In postoperative prostate cancer, depending on the amount of PSA antigen, different conditions may develop for the patient, including local recurrence, metastasis, local recurrence, and death; Therefore, instead of an event occurring, prostate cancer screening should be defined as a multidisciplinary process focusing on transitions between clinical conditions and the dynamic effect of the PSA marker on it. Careful monitoring of the disease and recording the amount of this enzyme and the conditions that occur for each patient will help doctors to make a better diagnosis.
Various factors increase the risk of prostate cancer, including heredity, age, hormonal factors, race, etc. In this study, we tried to test the two variables of age and Gleason score. Prostate cancer is one of the cancers that has a lower risk of death. Due to this, more data collection, due to the lack of recurrence of elderly patients, as a result of their failure to refer and follow up, faced problems that, despite much effort, led to a decrease in patients in this study.
This study is the first study in Iran to study the effect of two variables, age and Gleason score on status change in elderly patients over 60 years of age who have prostate cancer and have undergone surgery. According to the results, it was found that the Gleason score did not affect the transition between the considered conditions and age was significant only in the transition from surgery to hormone therapy; Therefore, in elderly patients who have undergone surgery, the risk of metastasis increases with age.

Ethical Considerations
Compliance with ethical guidelines
This study was approved by the Research Committee of University of Social Welfare and Rehabilitation Sciences.

Funding
The study was extracted from MA. thesis of the first author at the Department of Biostatistics and Epidemiology, Faculty of Rehabilitation Sciences, University of Social Welfare and Rehabilitation Sciences. 

Authors' contributions
All authors contributed equally in preparing this article.

Conflicts of interest
The authors declare no conflict of interest.


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