With improved treatments, especially the use of anti-cancer immunotherapies, more than two-thirds of all patients diagnosed with diffuse large B-cell lymphoma (DLBCL) will survive.
However, after treatment, patients are at a small but real risk of developing a new cancer, called a second primary cancer.
Now a study of long term DLBCL survivors shows, for the first time, that the stage at which DLBCL is originally diagnosed impacts the types of second cancers that may form after treatment.
These findings have been published in the journal Cancer.
“We have made tremendous progress in this field, and as a result, patients are living longer. Thus, survivorship has taken centre stage in the management of these lymphomas. Given that these patients are at an increased risk of developing second primary cancers, our goal is to identify risk factors that can predict or mitigate this risk,” said Manali Kamdar, MD, investigator at the University of Colorado Cancer Center and Clinical Director of Lymphoma Services at UCHealth University of Colorado Hospital.
The study explored the outcomes of 26,038 patients diagnosed with DLBCL between 1973 and 2010, more than half of whom were diagnosed with stage 1 or 2 disease, and a little less than half of whom were diagnosed with stage 3 or 4 disease.
Overall, 13 percent of survivors went on to develop second primary cancers.
“We’ve known that, genetically, early and late stage disease is different, and our hypothesis was that the type and timing of secondary primary cancers may thus be different as well,” Kamdar added.
In fact, the study showed that compared with late-stage cancers, patients diagnosed with early-stage DLBCL had a higher risk of developing second primary cancers in the five years following successful treatment, and that these new cancers tended to be mostly solid tumours, such as those of the breast, colon, or prostate.
In contrast, patients whose DLBCL was stage 3 or 4 at the time of diagnosis had an increased risk of developing second primary cancers in the 10-15-year window after successful treatment, and instead of solid tumours, these cancers tended to be haematologic malignancies, including forms of leukaemia.
“This is a first step toward identifying tools in survivorship clinics to better surveil survivors. It benefits patients because we may be able to better identify risk,” Kamdar said.
For example, Kamdar, suggests that if a patient were to find low blood counts 10 years after treatment for late-stage DLBCL, it would warrant further testing given the risk associated with a history of late-stage DLBCL.
Similarly, the study reinforces the need for DLBCL survivors to follow through with age-based screening recommendations, such as colonoscopies and mammograms.
Kamdar and colleagues hope this study will lead the way for prospective trials with the goal of decreasing not only DLBCL relapse, but also the development of second primary cancers.