Current Status of Radiotherapy Services in Kenya

Purpose: Owing to the missing recent data regarding cancer case volumes in Kenyan hospitals since 2012, the aim of the study was to fill the gap by providing data for two hospitals in Nairobi, the post year 2012. The general situation of radiation oncology and recommendation for improvement of radiotherapy services in the country were also highlighted. Further assessment was to investigate and determine the relationship between age, different types of cancer, and gender for cancer patients undergoing radiotherapy treatment. Materials and Methods: A data compilation, analysis, and evaluation process were conducted at two cancer treatment centers in Kenya followed by an assessment of radiotherapy cancer treatment facilities in the country. The number of the patients treated for cervical, breast prostate, esophagus, rectum, and lung cancer against their ages and gender were also compiled for assessment. Results: The number of cancer patients treated by radiotherapy continuously increased annually and he trends of the graphs in both centers were similar. Cervical cancer was the most common cancer treated by radiotherapy at the two centers, followed by breast and prostate cancer. Different types of cancer assessed were dependent on age and that cancer appeared at younger ages in female cervical and breast cancer patients as opposed to the male prostate cancer. Conclusion: The results indicate a continuous annual increase in cancer patients treated by radiotherapy in Kenya radiotherapy centers. The increase may be attributed to the rising population, limited access to cancer awareness, and the growing adoption of unhealthy lifestyles, among other factors. Female cervical and breast cancer patients contracted the disease at younger ages (46 - 50 years) compared to the male prostate cancer patients with a mean age of 61 - 65 years. Socio-economic factors, the organization of healthcare systems, and a limited workforce have been identified as some of the barriers to the provision of proper radiotherapy services in the country.

An age-structured model of the human papillomavirus dynamics and optimal vaccine control

We formulate an age-structured model based on a system of nonlinear partial differen- tial equations to assist the early and catch up female vaccination programs for human papillomavirus （HPV） types 6 and 11. Since these HPV types do not induce permanent immunity, the model, which stratifies the population based on age and gender, has a susceptible-infectious-susceptible （SIS） structure. We calculate the effective reproduction number Rv for the model and describe the local-asymptotic stability of the disease-free equilibrium using Rv. We prove the existence of an endemic equilibrium for Rv 〉 1 for the no vaccine case. However, analysis of the model for the vaccine case reveals that it undergoes the phenomenon of backward bifurcation. To support our theoretical results, we estimate the age and time solution with the given data for Toronto population, when an early and catch up female vaccine program is adopted, and when there is no vaccine. We show that early and catch up female vaccine program eliminates the infection in both male and female populations over a period of 30 years. Finally, we introduce the optimal control to an age-dependent model based on ordinary differential equations and solve it numerically to obtain the most cost-effective method for introducing the catch up vaccine into the population.