Short summary

The aim of the present project is to implement smoking cessation support in hospital-based lung cancer diagnostic workup. The effect on 1) patients' smoking cessation attempts, motivation, quality of life and psychosocial consequences of lung cancer workup as well as 2) hospitals' number of referrals to smoking cessation programmes will be evaluated in a pragmatic, cluster-randomised controlled setup. Patients' and HCPs' experiences and barriers will be explored in an interview-based study.

Rationale

Lung cancer is the second most common type of cancer in Denmark, and the disease is characterised by rapid progression with a 5-year survival rate of 12%. Patients with lung cancer struggle with symptoms such as breathlessness, pain, fatigue and impaired functioning, which typically intensify towards end-of-life. Resective surgery can have curative intent, but oncological treatment is most often focused on life prolongation, symptom reduction and quality of life and can consist of a combination of surgery, chemo- and or radiotherapy.

Smoking plays a central role in lung cancer disease progression. In countries with relatively high smoking prevalences, up to 90% of lung cancer diagnoses can be attributed to tobacco smoking. A considerable proportion of patients with lung cancer consider smoking after diagnosis, which has been shown to result in reduced quality of life, reduced effect of conventional treatment (surgery, chemotherapy, radiotherapy) and reduced survival.

Smoking cessation has demonstrated effect sizes that are comparable to those of conventional oncological and surgical lung cancer treatment and is therefore considered an essential and cost effective intervention across disease stages. In spite of

1) the evidence-based efficacy of smoking cessation and

2) the estimation that 70% of lung cancer patients wish to quit smoking, only a minority of lung cancer patients give up smoking on their own, and the majority needs professional support.

The Danish national guidelines for lung cancer treatment ("kræftpakke") and smoking cessation support in lung cancer state that professional support for smoking cessation should be initiated already during hospital-based lung cancer workup. This is supported by studies indicating that chances of successful smoking cessation are higher relatively soon after the time of severe illness diagnosis. Therefore, lung cancer workup can be considered a 'window of opportunity' for the initiation of smoking cessation support.

Nonetheless, international studies indicate that the actual delivery of smoking cessation support in clinical practice is limited. For example, a cross sectional registry-based study of American patients with lung cancer showed that only 36% received smoking cessation counselling. A registry-based study of Danish patients with lung cancer showed that only 25% of patient that died within the first year after diagnosis had stopped smoking, while 40% of the patients that survived the first year after diagnosis succeeded with smoking cessation.

According to the Danish Health Au-thority's tobacco prevention plan, the Danish municipalities are responsible for providing sys-tematic, evidence-based smoking cessation programmes for individuals that wish to stop smoking. However, in spite of the national focus on cross sectional referral of hospital-based patients to smok-ing cessation programmes in the local communities via the 'Very Brief Advice' (VBA method), the number of referred patients are suboptimal, and there has not been a specific focus on lung can-cer workup as an important time frame for initiation of smoking cessation support. Therefore, the initiation of smoking cessation support during hospital-based lung cancer workhop has great poten-tial for improving attempts to quit.

The existing literature gives examples of patients' and healthcare professionals' (HCP) barriers for initiating smoking cessation support in healthcare settings. For example, in a systematic review it is described that many HCPs consider smoking cessation support as too time demanding and ineffi-cient, paired with their conception that they lack knowledge on and training in smoking cessation support. Moreover, existing literature indicate that HCPs may in some cases be worried that smoking cessation will lead to reductions in quality of life, and that smoking cessation is point-less for patients that are candidates for a disease with a very poor prognosis. Yet, to our knowledge, no studies have so far addressed barriers to smoking cessation specifically in the context of hospital-based lung cancer workup.

Description of the cohort

The project is administered and initiated at the Department of Medicine, Vejle Hospital. In addi-tion, participating hospitals include Aalborg University Hospital, Aarhus University Hospital, Bispebjerg Hospital, Gentofte Hospital, Næstved Hospital, Odense University Hospital, Sygehus Sønderjylland (Sønderborg) and Zealand University Hospital (Roskilde).

Data collection will be initiated in March 2022 and is expected to proceed until December 2023.

Individual patients will be invited to take part in the evaluation when they receive their hospital in-vitation letter prior to their first visit in the lung cancer workup clinic.

• Inclusion criteria: >18 år; speaks and understands Danish.

• Exclusion criteria: unable to complete electronic questionnaires

Written participant information will be included in the lung cancer workup invitation letter together with a link to the electronic baseline questionnaire package. Prior to completing the questionnaire, the patient will be informed about who to contact in case they need oral information about the project, and they will be invited to give their written consent to participate in the questionnaire evaluation.

A subgroup of participants from hospitals in the intervention arm, as well as a number of healthcare professionals from the participating hospitals, will be invited to participate in semi-structured inter-views.

Data and biological material

Questionnaire data:

- Attempt to quit

- Motivation to quit

- Smoking status

- Nicotine addiction

- Quality of life

- Psychosocial consequences of diagnostic workup

- Sociodemographic information

- Smoking history

- Invitation to take part in qualitative evaluation

Data from electronic patient records:

- date of referral to diagnostic workup

- types of procedures during diagnostic workup

- results of diagnostic workup

Hospital-based registries

- number of referrals to community/municipality-based smoking cessation programmes.