Adrienne Weeks, MD, PhD, FRCSC – Dalhousie University, NS

Co-Investigators: Dr Jeremy Roy and Dr Lauren Westhaver

Project: “Comprehensive immunophenotyping via flow cytometry of primary tumor tissue and longitudinal peripheral blood mononuclear cells from patients with glioblastoma to distinguish pseudoprogression from true progression”

Generously funded by DUNN with Cancer

Description of Project:

The Weeks and Roy laboratory set out in 2020 to establish the largest longitudinal blood collection for brain tumour patients in Atlantic Canada. We aim to utilize this large patient cohort to further understand how the immune system, glioblastoma, and treatments interact in brain cancer progression. After brain cancer treatment, patients undergo MRI imaging to look for progression. Unfortunately, in a subset of patients, treatment response can look like progression on MRI; this is known as pseudoprogression. This often delays treatment decisions until the next MRI scan. This knowledge gap leads to delays in care which has a negative impact on quality of life. We hypothesize that by understanding changes in immune profiles in the blood of patients undergoing treatment, we can better inform patients and their clinicians on pseudoprogression versus true progression and improve care.

What receiving this award means:

“In reading Allison’s story, we see reflected many of our own patients and our own experiences as parents, daughters, partners, surgeons and researchers. This is a horrible cancer that robs families of time and memories. From our research family, we thank Allison’s family for supporting the Brain Tumour Foundation in promoting research that can, in turn, shed light on brain cancer. This award means our research can continue to understand how the immune system changes throughout the disease course to identify more effective cancer treatments and timely interventions and improve quality of life. Without the support of the Brain Tumour Foundation and the donor DUNN with Cancer, our research could not continue. We are very grateful and thank you on behalf of our entire research family and the families of the patients we treat.

Midpoint Update | June 2025

In the first year of our project, we’ve been working on a special test to better understand the immune system in people with brain tumours. This test examines 56 signals from immune cells in blood and tumour samples using a laboratory technique called flow cytometry.

We’ve also continued recruiting new patients and collecting their samples. Now that the test is working well, we’ve started analyzing blood from healthy people to see what “normal” looks like. This helps us spot important differences in patients later on.
Next, we’ll begin studying the samples we’ve collected from patients. By comparing individuals with actual tumour growth to those experiencing a treatment side effect called pseudoprogression, we hope to identify immune-system patterns that can help doctors make faster, more accurate decisions. In the long run, this could lead to better care and new treatment options for people living with glioblastoma.

Final Report | October 2026

We are pleased to report that we have successfully completed the project’s core objectives, with additional analysis and sample collection ongoing. We have collected and preserved blood and tumour samples from patients with glioblastoma, as well as blood samples from healthy control samples and patients with non-glioblastoma metastatic brain tumours.

We developed a flow cytometry-based technique to characterize immune cells in blood and glioblastoma tumours collected during surgery. To date, we have characterized immune cells in more than 125 samples collected at different disease stages, including diagnosis, during treatment, progression, and in control samples. We also analyzed samples from people who experienced pseudo-progression, a phenomenon in which a brain scan appears to show tumour growth when the change reflects immune-system and treatment interactions with the tumour, rather than true cancer growth.

In addition to studying immune cells, we also analyzed cytokines, signals immune cells use to communicate with one another, in the liquid (plasma) component of blood. Using Luminex technology, we measured many cytokines simultaneously in patient blood samples.

Our analyses have identified differences in immune profiles between healthy controls, patients with glioblastoma at diagnosis, and patients with non-glioblastoma brain metastases. We have also identified preliminary associations between immune profiles at diagnosis and patient survival.

We have presented our findings at multiple scientific conferences to gather feedback from the research community and received recognition for this work through several presentation awards. We continue to collect samples and clinical information to strengthen our analysis of progression and pseudo-progression. We will present our latest findings at the European Association of Neuro-Oncology meeting in September 2026 and are preparing a manuscript describing our findings in healthy controls, glioblastoma at diagnosis, and non-glioblastoma brain metastases. A second manuscript will focus on progression and pseudo-progression as additional samples become available.

The immune profiling panels and sample biobank developed through this program have opened new local and national collaborative opportunities. This infrastructure has allowed us to partner with the CCS Glioblastoma Research Program/Lundin Cancer Fund and with Dr. Marco Marra at the University of British Columbia, as well as with local investigators including Dr. Kimberly Brewer and Dr. Ian MacDonald.

Together, these findings advance our understanding of how the immune system responds to glioblastoma and its treatment and may improve disease monitoring and quality of life for Canadians affected by brain tumours.