In an Australian study reported in JCO Oncology Practice, Piercey et al found that routine blood tests have little utility in detecting relapse or progression of disease during active surveillance of patients with indolent non-Hodgkin lymphoma.
As stated by the investigators, “Patients with indolent non-Hodgkin lymphoma undergo regular active surveillance in between treatment periods to detect disease relapse or progression. As part of surveillance, international guidelines recommend regular routine blood testing, which is based on consensus rather than evidence of utility.”
“Routine blood tests have poor performance characteristics and rarely detect clinically significant disease progression or relapse in asymptomatic patients with indolent non-Hodgkin lymphoma."— Piercey et al
Tweet this quote
The study was a retrospective analysis of data from 180 patients age 16 or older diagnosed with grade 1 to 3A follicular or marginal zone lymphoma between 2008 and 2017 at two Australian cancer centers. The analysis assessed the utility of routine blood tests, including full blood examination, lactate dehydrogenase level, and β2-microglobulin, in detecting progression events, defined as either disease relapse or progression of disease.
The 180 patients had a total of 1,757 outpatient appointments for clinical review over a median follow-up of 36 months. Routine blood tests were performed before 1,461 appointments (83%) and were abnormal in 298 instances (20%).
A total of 74 progression events occurred in 62 patients (34%) at a median of 19 months (range = 1–105 months) from the start of a surveillance period. Overall, 2 (3%) of 74 progression events were detected by routine blood tests alone; 7 (9%), by routine imaging alone; and 65 (88%), by clinical signs or patient-reported symptoms. Of these cases, 2 of 2, 4 of 7, and 52 of 65 required immediate treatment, respectively.
Among 296 instances in which patients did not undergo routine blood tests before an appointment, eight patients (accounting for 3% of instances) were subsequently diagnosed with a progression event, including seven on the basis of clinical suspicion and one on the basis of routine imaging.
The overall sensitivity and positive predictive value of abnormal routine blood test results in detecting progression events was 39% and 9%, respectively.
At 1,298 visits for asymptomatic patients, routine blood test results were abnormal at 243 (19%). Among these, 223 instances of abnormal findings resulted in no additional investigations, and planned active surveillance was continued. In the remaining 8%, additional investigations were performed, including imaging (10 cases), further blood tests (8 cases), tissue biopsy (1 case), and bone marrow assessment (2 cases), or frequency of clinical surveillance was increased without additional investigations (5 cases). Progression events subsequently occurred in two patients (accounting for 0.8% of instances of abnormal routine blood test results).
The investigators concluded, “Routine blood tests have poor performance characteristics and rarely detect clinically significant disease progression or relapse in asymptomatic patients with indolent non-Hodgkin lymphoma…. These results suggest that, in contrast to current guidelines, the use of blood tests should be considered in the context of the clinical scenario in follow-up of patients with marginal zone or follicular lymphoma but blood tests should not be used routinely in the absence of symptoms.”
Eliza A. Hawkes, DMedSc, of the Department of Oncology and Clinical Haematology, Olivia Newton-John Cancer Research and Wellness Centre, Victoria, is the corresponding author for the JCO Oncology Practice article.
Disclosure: For full disclosures of the study authors, visit ascopubs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.