Survival of patients with non-Hodgkin lymphoma in England: investigating the socioeconomic inequalities

Non-Hodgkin lymphoma is a heterogeneous group of malignancies characterised by various behaviours and prognoses. Two of the most common subtypes are diffuse large B-cell lymphoma and follicular lymphoma, where patients with either can have markedly different health outcomes. Survival probability is commonly used to measure the performance of a healthcare system in managing cancer patient health outcomes in a population, such as England. In England, the National Health Service is responsible for the care and management of patients and their health outcomes, and is committed to providing equal access to healthcare regardless of the patient’s underlying characteristics. However, although cancer patients are now more likely to live to 5 years after diagnosis, there are vast inequalities in survival between patient characteristics. Socioeconomic inequalities in survival, for all cancers, have narrowed since the late 20th century but these socioeconomic-gaps in survival persist. Comorbidity, the presence of a chronic disease unrelated to the cancer, is more prevalent amongst individuals living in more deprived areas. These socioeconomic gaps in survival may be explained by the presence of comorbid conditions or by the interaction between patients and the healthcare system. The aim of this PhD is to investigate the inequalities in survival of patients with non- Hodgkin lymphoma in England using population-based cancer registry data linked to other population-based health outcomes databases. This thesis includes one paper investigating the association between patient and healthcare pathway characteristics and long-term survival probabilities, another paper that focuses on inequalities in short-term survival probability, and a final paper on inequalities in diagnostic delay. An additional paper was written concurrently to this thesis that provides a tutorial on the methods, amongst others, that were used for the paper investigating short-term survival.