New testing modalities are poised to improve diagnosis and prognosis
According to John M. Burke, MD, improving our diagnostic and prognostic capabilities is one of the most important and exciting ways to improve the way we care for cancer patients.
Last year, a 70-year-old woman presented to her (and my) local hospital with a seizure. An MRI of the brain revealed a 2.4 cm mass in the left temporal lobe. A lumbar puncture showed lymphocytes and elevated protein, and cerebrospinal fluid flow cytometry detected malignant B cells. A craniotomy was performed and a biopsy of the brain tumor, read by an expert pathologist from an academic institution, indicated grade 1 lymphomatoid granulomatosis – not a diagnosis that I personally am used to seeing on a brain biopsy , it’s the least we can say.
This work took a while, and then I had to scramble to try to figure out how to handle the extremely rare situation of lymphomatoid granulomatosis of the brain.
My patient and I decided to start rituximab (Rituxan). However, at the request of the family, I sought a second opinion on the pathology. Several weeks later, the second expert pathologist, who was at another academic institution, informed me that it was not lymphomatoid granulomatosis, but rather diffuse CD5-expressing large B-cell lymphoma. . So after giving this patient 3 weekly doses of rituximab, I changed her treatment to rituximab, methotrexate, vincristine and procarbazine. A year later, she remains in complete remission.
Wouldn’t it be great if we could reliably diagnose central nervous system lymphoma without an invasive brain biopsy? A potential solution to this problem, and perhaps to many others that we face in our field, is discussed in the Precision Medicine in Oncology section of this issue: “Exploring prognostic tests in hematological malignancies” (page 67).
New testing modalities are already changing the practice of hematology and oncology and are likely to do so even more in the future. One example that has affected clinical practice is the test for measurable residual disease, or MRD. In acute lymphoblastic leukemia, MRD test results after multi-agent chemotherapy are now used to select patients for treatment with the bispecific T-cell engaging blinatumomab (Blincyto).
Improving our diagnostic and prognostic testing capabilities is certainly one of the most important and exciting ways to improve the way we care for cancer patients. I predict that 10 to 20 years from now, the way we diagnose cancer, choose therapies, adjust treatments during therapy, and monitor for relapses will be very different from what we do today. …at least I hope so, for the good of the patient.