title: Health systems factors in advanced stage diagnosis of head and neck cancer
Creators: name: Creaney, Grant
Publisher: name: University of Glasgow
Year: 2025

description: Background: Globally, head and neck cancer (HNC), comprising of squamous cell carcinomas of the oral cavity, oropharynx, larynx, and other sites of the head and neck, is the 7th most common cancer grouping by incidence and 9th by mortality. People with HNC have poor overall survival, with an estimated 50% 5-year survival. One of the key prognostic factors is stage at diagnosis, with people diagnosed with advanced stage HNC at diagnosis, categorised as stage III or IV in the Tumour, Nodes, Metastases (TNM) classification, having poorer outcomes than those with early-stage disease (stages I and II). The burden of advanced stage HNC in the UK is not quantified and factors associated with advanced stage at diagnosis, particularly health systems factors, not well researched or understood. There is a paradigm shift happening in health services research with the understanding that pragmatic approaches embracing complexity are needed. With advanced stage HNC presenting a public health challenge in the UK and internationally, ascertaining the full nature of the burden of advanced stage HNC and the factors associated with advanced-stage diagnosis are key to prepare system changes and interventions to improve early detection rates.

Aims: This thesis is split into three separate studies each focussing on specific aims:

i) Chapter Three: To quantify the burden of advanced stage HNC across the countries of the United Kingdom through analysis of routinely collected cancer registry data, and to begin to assess the distribution of stage of HNC by socio-demographic factors.

ii) Chapter Four: To identify health systems factors associated with stage at diagnosis through a novel benchmarking survey of international HNC centres.

iii) Chapter Five: To explore the role of health systems factors in advanced stage diagnosis of HNC through qualitative analysis of two HNC centres: Glasgow, Scotland and Montevideo, Uruguay.

Methods: A mixed-methods approach was undertaken in this thesis. Each study had specific methodological approaches:

i) Chapter Three: Collecting routinely collected, aggregated cancer registry data from the four Cancer Registries of the UK via detailed specification of HNC data requests (2009-2018). Data were collated and harmonised. Descriptive epidemiological analysis of trends and the burden of advanced stage across the four countries was performed by HNC overall and subsite groupings. Additional, analysis was undertaken for the Scottish Cancer Registry stage of HNC and subsites by age grouping, sex, and area-based socioeconomic status measured by the Scottish Index of Multiple Deprivation (SIMD) of home postcode.

ii) Chapter Four: A bespoke health systems questionnaire was sent to 18 international HNC centres, to the Head and Neck Cancer in South America and Europe (HEADSpAcE) Consortium centre leads. The questionnaire included items on various health system domains capturing both quantitative and qualitative data on the local pathways to diagnosis of HNC and burden of advanced stage HNC. These data were collated and categorised into health systems factors and HNC centres were then benchmarked according to the local proportion of advanced stage HNC and the presence/absence of these factors within their local HNC diagnostic pathway. Analysis for each health system factors was undertaken to assess the impact of each factor on the
proportion of advanced stage HNC through least square means tests. Qualitative descriptions of the patient pathways to HNC diagnosis for all centres were collated and harmonised into an adapted diagnostic interval model.

iii) Chapter Five: A qualitative follow-on study to the research undertaken in Chapter Four was conducted in two centres (Glasgow, UK and Montevideo, Uruguay) and comprised 29 semi-structured, in-depth interviews undertaken with a range of stakeholders across both sites, including surgeons, oncologists, primary care practitioners, and HNC patients. The interviews used specifically created topic guides; and were undertaken by trained and standardised interviewers. Interviews were recorded, transcribed, and translated where required to enable analysis. A thematic template analysis was undertaken with 16 key health system themes and 45 sub-themes identified across the different intervals of HNC diagnosis and subsequently applied to the framework of the systems engineering initiative for patient safety (SEIPS) 3.0.

Results: Key findings from each study were:

i) Chapter Three: Descriptive analysis revealed that in the UK 59% of HNCs where stage is recorded were found to be at advanced stage at diagnosis in 2016-2018, with stage IV the most common stage at diagnosis for all HNC. Cancer Registry data on stage at diagnosis had improved year on year and was 87% complete by 2018. Further analysis of the Scottish Registry data found males to have higher odds of having advanced stage HNC than females (odds ratio (OR) 1.24, 95% Confidence Interval (CI) 1.05, 1.46), and those who are diagnosed with HNC from the 20% most socioeconomically deprived areas had greater odds of having advanced stage at diagnosis when compared to those in the 20% least socioeconomically deprived areas, although the association was not as strong (OR 1.14, 95% CI 0.89, 1.48).

ii) Chapter Four: Health systems factors were shown to be associated with a lower proportion of advanced stage HNC including formal referral triaging (14%, 95%CI-0.26, -0.03), routine monitoring of time from referral to diagnosis (16%, 95%CI-0.27, -0.05), and fully publicly funded systems (17% 95% CI-0.29, -0.06). Several health system factors were found to have a lack of routinely collected data at HNC centre, including routine reporting of proportion of advanced stage locally, workforce numbers and whole-time equivalent of different specialties and grades, HNC referral source, routine reporting of referrals leading to confirmed HNC diagnosis, and performance indicators relating to referral/pre-diagnosis. Additionally, the variance in pathways to HNC diagnosis across the HNC centres in this study were harmonised into a universal pathway to HNC diagnosis.

iii) Chapter Five: Key health system themes identified included public awareness and ability to act on HNC symptoms (i.e. navigate into and through pathways to diagnosis), the underlying role of socioeconomic/geographic inequalities, and the disconnect/communication barriers between care teams – specifically primary and secondary care. In applying the thematic results to the SEIPS framework, a systems understanding of how the themes relate to the various elements and processes of HNC diagnostic pathways was formed, illustrating the complexity whilst highlighting how these factors may be navigated (through focus on people, tasks, environment, or organisations).

Conclusions: This thesis presents and describes a high burden of advanced stage HNC across the nations of the UK, identifies important health systems factors in advanced stage HNC across international HNC centres, develops a harmonised HNC diagnostic pathway, and further explores the main factors associated with stage at diagnosis of HNC from two HNC centres, Glasgow in Scotland and Montevideo in Uruguay.

This research undertaken in this thesis includes the first fully focused health systems factors investigation into advanced stage diagnosis of HNC through a systems approach to international HNC diagnostic pathways. The findings from this research present key considerations for health system/service change to improve earlier diagnosis of HNC internationally.