Lack of a Prognostic Impact of the MyD88 L265P Mutation for Diffuse Large B Cell Lymphoma Patients Undergoing Autologous Stem Cell Transplantation

Good clinical response following Ibrutinib treatment of a rare case of lymphoplasmacytic lymphoma secreting IgA kappa paraprotein: A case report

Lymphoplasmacytic lymphoma (LPL) is a malignant proliferation of small lymphocytes, lymphoplasmocytoid cells and plasmocytes affecting the bone marrow, lymph nodes and spleen. Its incidence is 1/100,000 and represents 8% of all lymphomas. A total of ~5% of patients with LPL may secrete non-IgM of IgG, IgA, kappa or lambda type or be non-secretory. In the present study, a case of a 62-year-old female patient who was diagnosed with non-IgM LPL with kappa light chain monoclonal paraprotein production and normal serum immunoglobulin levels was reported. The MYD88 L265P mutation was detected by molecular genetic analysis using a sample of the bone marrow. The patient underwent initial treatment with a combination of Bendamustine-Rituximab, and later on, Ibrutinib (a Bruton kinase inhibitor) was added to the treatment protocol. The authors' aim was to describe a case of a rare type of LPL studied and cured at the University Hospital 'St. Ivan Rilski', as well as to show the methods used for its diagnosis and their applicability. The difficulty in diagnosing such rare cases of LPL which are associated with marked plasmacytic differentiation and IgA paraprotein secretion resembling plasma cell neoplasia was addressed. From the other side, the characteristic features in favor of LPL diagnosis are the immunophenotype profile of plasmocytes, as well as the presence of MYD88 L265P mutation. Finally, the methods of management and treatment of this type of lymphoma were reported, highlighting the favorable effect of the treatment with Bruton TK inhibitor (Ibrutinib).

Prognostic impact of MYD88 and TP53 mutations in diffuse large B Cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is the most common subtype of lymphoma. It is a highly heterogeneous lymphoid neoplasm, with variations in gene expression profiles and genetic alterations. MYD88 and TP53 genes are common to be expressed and mutated in DLBCL patients with controversy regarding their role in prognosis and survival. This study aims to determine the predictive and prognostic role of MYD88 and TP53 gene mutation in DLBCL. A prospective cohort study was conducted on 50 patients who were diagnosed with DLBCL and 30 healthy individuals to assess the sensitivity and specificity of MYD88 and TP53 genetic mutations. MYD88 and TP53 gene mutations were more sensitive, specific, and accurate in predicting overall mortality and disease progression in comparison with the international prognostic index. Mutant MYD88 and TP53 showed their prognostic importance for worse objective response rates and survival outcomes. Both mutant MYD88 and TP53 were associated with worse ORR. There was a significant statistical difference for both MYD88 and TP53 with regard to 2-year PFS and 2-year OS rate. Hence, both mutant MYD88 and TP53 can be used in predicting disease progression and overall mortality.

Impact of Cell of Origin Classification on Survival Outcomes after Autologous Transplantation in Relapsed/Refractory Diffuse Large B Cell Lymphoma

The cell of origin (COO) classification into germinal center B cell (GCB) and non-GCB types has been shown to predict survival outcomes in newly diagnosed diffuse large B cell lymphoma (DLBCL). In the relapsed/refractory (R/R) setting, there is building evidence that COO does not predict prognosis after high-dose chemotherapy and autologous stem cell transplantation (auto-SCT). The present analysis aimed to compare survival outcomes based on COO classification in R/R DLBCL patients who underwent auto-SCT. This retrospective study included adult patients with R/R DLBCL who underwent auto-SCT at MD Anderson Cancer Center between January 2007 and December 2016. The Hans algorithm using CD10, BCL6, and MUM1 markers was used to classify patients by COO. A total of 122 patients with DLBCL (71 GCB, 51 non-GCB) were included in the analysis. There were no significant differences in patient characteristics between the 2 groups, except for older median age in the GCB cohort (64 years versus 58 years; P < .004). The median overall survival (OS) time was 68.5 (95% confidence interval [CI], 51.3 to not reached) months for the total population, 68.5 (95% CI, 44.8 to not reached) for GCB, and not reached for non-GCB. The 3-year OS rate was 0.659 (95% CI, 0.575 to 0.755) for the total population, 0.653 (95% CI, 0.547 to 0.779) for GCB, and 0.666 (95% CI, 0.537 to 0.824) for non-GCB. When adjusted for age and other factors of interest, no statistically significant associations for OS or progression-free survival were observed between the 2 cohorts. Our results confirm that COO loses its prognostic potential in patients with R/R DLBCL who receive high-dose chemotherapy followed by auto-SCT and both GCB and non-GCB types of DLBCL derive similar benefit from auto-SCT. Younger age, female sex, and pretransplantation disease status were associated with better OS.

Prognostic value of MYD88 L265P mutation in diffuse large B cell lymphoma via droplet digital PCR

To assess the prevalence and prognostic value of myeloid differentiation factor 88 (MYD88) expression and mutational status in diffuse large B cell lymphoma (DLBCL), a total cohort of 100 patients with DLBCL were studied using immunohistochemistry (IHC) and droplet digital polymerase chain reaction (DDPCR), and the association between MYD88 expression and clinicopathological parameters was analyzed. Overall, the positive expression rate of MYD88 protein was 38% and the gene mutation rate was 29%. The positive expression and mutation rates were the highest in the primary central nervous system lymphomas (58.33 and 66.67%, respectively). The coincidence rate of the results of MYD88 expression between IHC and DDPCR results was 73% (73/100). Univariate survival analysis showed that age (≥60 years old), high neutrophil/lymphocyte count ratio, low lymphocyte count, c-Myc ≥40%, positive MYD88 protein expression, and gene mutation were associated with poorer prognosis rates. Multivariate survival analysis revealed that MYD88 expression was an independent prognostic factor affecting overall survival. In conclusion, the results of this study demonstrated that MYD88 mutation was a valuable index to evaluate the prognosis of DLBCL. DDPCR can be used as a method for detecting MYD88 mutations, although it was not completely consistent with the results of IHC.

MYD88 in the driver's seat of B-cell lymphomagenesis: from molecular mechanisms to clinical implications

More than 50 subtypes of B-cell non-Hodgkin lymphoma (B-NHL) are recognized in the most recent World Health Organization classification of 2016. The current treatment paradigm, however, is largely based on 'one-size-fits-all' immune-chemotherapy. Unfortunately, this therapeutic strategy is inadequate for a significant number of patients. As such, there is an indisputable need for novel, preferably targeted, therapies based on a biologically driven classification and risk stratification. Sequencing studies identified mutations in the MYD88 gene as an important oncogenic driver in B-cell lymphomas. MYD88 mutations constitutively activate NF-κB and its associated signaling pathways, thereby promoting B-cell proliferation and survival. High frequencies of the hotspot MYD88(L265P) mutation are observed in extranodal diffuse large B-cell lymphoma and Waldenström macroglobulinemia, thereby demonstrating this mutation's potential as a disease marker. In addition, the presence of mutant MYD88 predicts survival outcome in B-NHL subtypes and it provides a therapeutic target. Early clinical trials targeting MYD88 have shown encouraging results in relapsed/refractory B-NHL. Patients with these disorders can benefit from analysis for the MYD88 hotspot mutation in liquid biopsies, as a minimally invasive method to demonstrate treatment response or resistance. Given these clear clinical implications and the crucial role of MYD88 in lymphomagenesis, we expect that analysis of this gene will increasingly be used in routine clinical practice, not only as a diagnostic classifier, but also as a prognostic and therapeutic biomarker directing precision medicine. This review focuses on the pivotal mechanistic role of mutated MYD88 and its clinical implications in B-NHL.

Prognostic impact of MYD88 mutation, proliferative index and cell origin in diffuse large B cell lymphoma

Background

Diffuse large B-cell lymphoma, among non-Hodgkin lymphomas, is one of the most frequent subtypes. Clinical laboratory data and post-treatment outcomes are scarce in the Brazilian population.

Objective

The main objective of this retrospective study was to assess the impact of tumor markers, including the Myeloid differentiation primary response 88 (MYD88) mutation.

Method

Eighty-three patients were included and treated with R-CHOP or R-CHOP-like regimens.

Results

Median age was 64-years old and 58% were female patients. The median follow-up was 42 months. The progression free survival (PFS) at this time was 63% and overall survival (OS), 66%. In the patients with tumors expressing Myc proto-oncogene protein (MYC) and B-cell lymphoma 2 (BCL2), assessed by immunohistochemistry (IHC), known as dual protein expressers, median post-progression survival was 31 (15–45) months. An increased proliferative index were associated with a high rate of progression (hazard ratio 2.31 [95% confidence interval [1.05–5.12]; p = 0.04). The cell of origin (COO), identified by IHC, was not able to predict PFS (p = 0.76). The MYD88 L265P mutation was present in 10.8% (9/83) of patients and did not show a prognostic correlation.

Conclusion

In conclusion, the MYD88 mutation, although an important tool for diagnosis and a possible target drug, presented at a low frequency and was not a prognostic marker in this population.