The prognostic utility of dynamic risk stratification at disease progression in patients with multiple myeloma

Prognostic value of the "dynamic" R2-ISS in patients with multiple myeloma undergoing anti-CD38 antibody-based triplet therapies

To retrospectively analyze whether the second revision of the international staging system (R2-ISS) influenced prognosis at treatment initiation in patients with multiple myeloma (MM) receiving anti-CD38 antibody-based triplet treatments. High-risk chromosomal abnormalities were examined from diagnosis to treatment initiation and considered positive if detected once. R2-ISS was recalculated at the initiation of treatment and defined as "dynamic R2-ISS." Data from 150 patients who underwent the defined treatments were analyzed. The median progression-free survival (PFS) was 19.5 months, and the median overall survival (OS) was 36.5 months. Dynamic R2-ISS significantly stratified prognoses for both PFS and OS. The median PFS for patients with dynamic R2-ISS IV was 3.3 months, and the median OS was 11.7 months, indicating extremely poor outcomes. Although the Revised International Staging System (R-ISS) calculated at the initiation of treatment significantly stratified treatment outcomes, the patients classified as R-ISS could be further stratified by R2-ISS to provide better prognostic information. Dynamic R2-ISS showed potential as a prognostic tool in patients with MM who are treated with anti-CD38 antibody-based triplet therapies.

Longitudinal genetically detectable minimal residual disease by fluorescence in situ hybridization confers a poor prognosis in myeloma

Background

Deeper depth of response (DpR) after induction therapy, especially gain of negative minimal residual disease (MRD), has been linked to prolonged survival in multiple myeloma (MM). However, flow-MRD examination focuses on the numbers but not on the biological characteristics of residual plasma cells (PCs).

Objectives

To explore whether the genetic features of residual tumor cells affect the survival time of patients with MM.

Design

A retrospective cohort study.

Methods

We investigated the clonality of cytogenetic abnormalities (CAs) of the residual PCs using interphase fluorescence in situ hybridization (iFISH) in the National Longitudinal Cohort of Hematological Diseases in China (NCT04645199). Here, a longitudinal cohort of 269 patients with patient-paired diagnostic and post-induction iFISH results was analyzed.

Results

Persistent CAs after induction therapy were detected in about half of the patients (118/269, 43%), and patients with undetectable CAs showed significantly improved survival compared with those with genetically detectable MRD [median progression-free survival (mPFS): 59.7 versus 35.7 months, p < 0.001; median overall survival (mOS): 97.1 versus 68.8 months, p = 0.011]. In addition, different patterns of therapy-induced clonal evolution were observed by comparing the clonal structure of residual PCs with paired baseline samples. Patients who maintained at a high risk during follow-up had the worst survival (mPFS: 30.5 months; mOS: 54.4 months), while those who returned to lower risk or had iFISH- at both time points had the best survival (mPFS: 62.0 months, mOS: not reached).

Conclusion

These findings highlighted the prognostic value of genetic testing in residual tumor cells, which may provide a deep understanding of clonal evolution and guide clinical therapeutic strategies.

The role of staging in multiple myeloma

INTRODUCTION

The importance of cancer staging is determined by how accurately it can predict prognosis, and how useful it is for treatment decisions. Compared to other malignancies, multiple myeloma (MM) staging proved more challenging because of unreliable prognostic factors and wide-ranging life expectancy. As traditional MM staging continues to evolve, it requires reassessment of its prognostic and predictive value.

AREAS COVERED

The studies that included prognostic and predictive value of MM stages from 1975 through 2023 were selected for this review using PubMed, MEDLINE platforms. The history and evolution of MM staging are revisited, including its role in predicting survival, treatment planning and potential practical implications for the future. The role of MM staging for oncological practice and patient counseling is discussed.

EXPERT OPINION

The utility of the traditional MM staging remains unsatisfactory because it lacks a strong connection with the disease biology, prognosis or treatment planning. Additionally, it demonstrates a modest value for patient counseling because individual prognosis is subject to under- or overestimation, and the median survival or survival rates are difficult concepts to grasp. Although the role of MM stages may change in the future, the current research upholds the notion that MM staging benefits more medical research and clinical trials than oncological practice.