The impact of concordance with a lung cancer diagnosis pathway guideline on treatment access in patients with stage IV lung cancer.

Background: Timely access to treatment of lung cancer is dependent on efficient and appropriate patient assessment and early referral for diagnostic workup. This study assesses the impact of Cancer Care Ontario (CCO) Lung Cancer Diagnostic Pathway Guideline (LCDPG) concordance on access to treatment of stage IV lung cancer patients referred to the Diagnostic Assessment Program (DAP) at a Canadian tertiary cancer centre. Methods: This retrospective cohort study includes patients diagnosed with clinical stage IV lung cancer referred to the DAP at a Canadian tertiary cancer centre between November 1, 2015 and May 31, 2017. Referral concordance was determined based on CCO LCDPG. The primary outcome; time to treatment from initial healthcare presentation; was compared between the concordant and discordant referrals. Results: Two hundred patients were referred for clinical stage IV lung cancer during the study period. Of these referrals, 151 (75.5%) were assessed and referred in concordance with LCDPG. Guideline concordant referrals were associated with reduced time to treatment from first healthcare presentation compared with guideline discordant referrals (55.3 vs. 108.8 days, P<0.001). Time to diagnostic procedure (32.2 vs. 86.7 days, P<0.001) and decision to treat (38.5 vs. 93.8 days, P<0.001) were also reduced with guideline concordance. The most common reason for discordant assessment and referral was delayed or inadequate investigation of symptoms in a high risk patient (32.7% of discordant referrals). Conclusions: Guideline concordant assessment and referral of stage IV lung cancer patients results in reduced time to diagnosis and treatment. Future research and education should focus on improving factors that delay DAP referral.