Time to Diagnosis and Treatment of Lymphoma: A Canadian Population Based Study

Introduction: Prompt diagnosis and treatment are key requirements to improving cancer patients' survival and quality of life. This is particularly relevant in diseases such as the aggressive lymphomas, which are potentially curable with appropriate therapy. The province of Manitoba (MB), Canada, has set a goal of reducing time from suspicion of any cancer to treatment to sixty days.

Objectives: To establish a provincial baseline this study examined time intervals in lymphoma patients' journey from high suspicion (HS) to diagnosis date (dx_dt) and treatment (tx). The aims were to determine the portion of patients achieving the goal of sixty days and compare this to other major cancers (Breast, Colorectal and Lung). The effect of place of residence at diagnosis, gender, age and lymphoma subtype on delays were also of interest.

Methods: Patients with a first diagnosis of any type of lymphoma between 01/2010 to 12/2013 were identified from the Manitoba Cancer Registry (MCR). Those with a prior cancer diagnosis, diagnosed by autopsy or death certificate only, or incomplete/pending MCR registration were excluded. We accessed provincial health insurance billing claims and hospital registration databases in the year prior to dx_dt. Working backwards from dx to determine the HS point, an algorithm was built using an iterative consultative process referencing chart reviews as a framework for milestones in the patient pathway. The index event for high suspicion (HS) was defined as the first event including: imaging ranked likely related to subsequent lymphoma diagnosis, diagnostic procedure/biopsy, or specialist consultation. Using this index event, the claims data were searched for a referring provider, the last visit with this provider was defined as the date of HS. The influence of lymphoma subtype was explored by examining intervals in patients with Diffuse large B-cell Lymphoma (DLBCL) and classical Hodgkin Lymphoma (HL).

Results: The entire cohort included a total of 1182 patients with 338 DLBCL (36.2%), 96 HL (10.3%) and 53.5% other types of lymphoma. The index event for HS was imaging in 477 (51.1%), specialist consult in 92 (9.9%), diagnostic procedure/biopsy in 42 (4.5%), ER visit in 24 (2.6%) and multiple index events in 274 (29.3%). HS-tx was less than sixty days in only 14.8% of patients. 31.3% of patients did not receive any treatment. In patients who received chemotherapy at diagnosis (n=682) HS-tx was less than sixty days in 22.3%. A parallel analysis for Breast, Colorectal and Lung cancers revealed that 29%, 33% and 38% met the target of HS-tx in less than sixty days at baseline. HS-tx was less than sixty days in 84 patients with DLBCL (24.9%) and 25 with HL (26%), p=0.06.

Conclusion: In this population based Canadian study, the proportion of lymphoma patients who meet the target for timely commencement of systemic therapy is low, even more than other major solid tumors. There is no difference between the proportion of HL and DLBCL patients meeting this target, which is in contrast to previously published literature that suggests longer delays in HL. In patients treated with chemotherapy a large portion of the delay appears to be after diagnostic biopsy (dx_dt). As part of this initiative clinical advisors have developed a lymphoma pathway with target timelines for milestones which will serve as a reference tool. This study describes the methodology that can be adopted in other jurisdictions treating lymphoma, and also serves as a baseline from which to direct process improvement.