Limited value of routine follow-up visits in chronic lymphocytic leukemia managed initially by watch and wait: A North Denmark population-based study

Abstract

Introduction: The majority of newly diagnosed chronic lymphocytic leukemia (CLL) patients are followed initially by watch and wait (WAW). Clinical practice varies and the value of frequent follow-up visits remains unclear. Thus, in this study we investigated the clinical value of follow-up visits for patients with CLL.

Methods: We collected data from diagnosis and follow-up visits for patients diagnosed with CLL and managed by WAW in the North Denmark Region between 2007-2014. High- and low-risk group patients were determined by Binet stage, IgVH status, and cytogenetics at diagnosis. The effect of risk group allocation on the probability of receiving CLL-directed treatment within two years was included in a multivariable logistic regression model adjusted for age and blood test results.

Results: 273 patients were included in the study with a median follow-up of 3 years (IQR: 1.6-5.4). Overall, the median interval between follow-up visits was 98 days (95% CI: 96-100) (high-risk patients: 91 days [95% CI: 86-95] vs. low-risk patients: 105 days [95% CI: 100-110]). Among 2,312 follow-up visits, only 387 (17%) were associated with interventions. At the following time points: 6 months, 1 year, and 1.5 years, patients with low-risk CLL had significantly lower odds of initiating treatment compared to patients with high-risk CLL.

Conclusion: WAW plays an important role in managing CLL. Interventions at follow-up visits were infrequent and low-risk patients had significantly lower risk of treatment initiation. We question the value of routine follow-up in CLL in the absence of changes in symptoms and/or blood test results.

Fig 1. Cumulative incidence of the probability of initiating treatment.

Cumulative incidence curves showing the probability of initiating treatment for low-risk patients (green) and high-risk patients (red).

Fig 2. Odds ratio of 2-year predicted treatment initiation.

Odds ratio for 2-year treatment initiation for patients at risk, estimated at the time points 6 months, 1 year, and 1.5 years post-diagnosis. The standardized thrombocyte count and hemoglobin level were multiplied by minus one in order to make the odds ratios correspond to a decrease in these counts.