Dr. Elhassadi on the Relationship Between p53 Expression and Prognosis in MCL

Ezzat Elhassadi, MD, consultant hematologist, Hematology Services, University Hospital Waterford, discusses p53 expression and prognosis in mantle cell lymphoma (MCL).

Part of the 10-year single-center experience of p53 status in MCL was to look at immunohistochemistry (IHC) for p53 expression. Notably, there was a 100% correlation between p53 profile expression by immunohistochemistry (IHC) and mutation status, says Elhassadi. Moreover, when Sanger sequencing was used by itself, only 3 mutations could be identified in the overexpressed cohort among 6 patients. When next-generation sequencing (NGS) was employed for the overexpressed group, investigators could identify the subclone as well. However, NGS is not used routinely in practice.

Sanger sequencing was used for all the samples, so the patients who had a low expression by IHC did not have underlying mutations—a finding that correlates with the mutation status. Since these data were reported at the 2019 EHA Congress, Elhassadi and colleagues have introduced p53 IHC screening into routine practice. This patient subset is known to have a very dismal outcome. Both the Nordic MCL-1 and -2 trials have reported a median overall survival of 1.3 years in this patient population, suggesting the insufficiency of standard treatment with intensive chemotherapy, transplant, and rituximab (Rituxan) maintenance.