January 2026 Research Update

This month added a clearer picture of which Waldenstrom macroglobulinemia patients do well after frontline bendamustine-rituximab (BR) and which patients are more likely to have the disease come back early. Across the reported group, longer-lasting control was common, but a smaller subset had progression within 24 months (often called POD24) and this subgroup had worse survival. These results help separate "most patients" from a higher-risk group that may need closer study in future research. [1]

In a multicenter report of 253 people treated with fixed-duration BR, 5-year progression-free survival was 65% and 5-year overall survival was 87%. POD24 happened in 23 of 201 evaluable patients (11.5%), and people with POD24 had worse survival when compared with those who did not progress early. The report also noted that patients without POD24 had survival similar to the general population, which is a reassuring benchmark for many patients treated with this approach. [1]

Genetics helped explain part of the difference: CXCR4 mutations were linked to shorter time without progression and worse overall survival, while MYD88 status did not meaningfully change 5-year progression-free survival in the subgroup with known testing. POD24 still predicted worse outcomes even after accounting for mutation status, suggesting early progression itself carries important information beyond any single test result. Because not everyone had mutation data, the size of these genetic subgroups was limited. [1]

For patients and caregivers, this study mainly adds perspective about prognosis after a common first treatment (BR), rather than changing what someone should do right now. It suggests that if the disease remains controlled past the first 2 years after BR, long-term outlook may be closer to what is expected in the general population, while early progression identifies a group that may face more challenges. It also supports the idea that CXCR4 mutation testing can be relevant for understanding risk, although the report does not say how to act on this information and testing was not available for all patients. [1]

This month included an early but practical idea: in Waldenstrom macroglobulinemia, measuring how much of the MYD88 or CXCR4 mutation is present over time may reflect disease burden more directly than following IgM alone. The pattern across samples was that bone marrow mutation levels tracked bone marrow involvement better than IgM changes did, and blood testing also showed a relationship, though less strongly. This matters because some treatments can change IgM in ways that do not perfectly match what is happening in the bone marrow, and patients often experience uncertainty when test results do not "line up." [2]

In an analysis using samples from five prospective trials (96 bone marrow and 60 blood samples), changes in bone marrow mutation level correlated with bone marrow disease burden (correlation r = 0.53). The link between IgM changes and bone marrow disease burden was weaker (r = 0.43), and blood mutation levels showed a moderate relationship with bone marrow findings. The study also reported that different treatment regimens showed different degrees of mutation-level reduction, including larger drops in some combination regimens than with ibrutinib alone. [2]

These measurements were done on CD19-selected cells and focused on common Waldenstrom-related mutations (MYD88 L265P and CXCR4 S338X). The work was exploratory and does not prove that using mutation levels will improve outcomes, but it makes the case that mutation-level tracking could complement IgM when researchers evaluate response in trials. The study did not present a patient-care pathway for using these tests in routine visits. [2]

For patients, this research may matter later rather than immediately, because it is proposing better ways to measure response, not a new treatment. It helps explain why IgM alone may not always feel like a perfect "scoreboard" for how the disease is doing, and it points to mutation-level testing in bone marrow or blood as a potential additional tool. What remains uncertain is how well these measurements predict day-to-day outcomes for individuals, and whether they will become standardized outside research studies. [2]

This month underscored that Waldenstrom macroglobulinemia is not only about controlling IgM or bone marrow disease; complications and side effects can drive major health events. A nationwide Finnish study reported improving survival over time, but infections and Waldenstrom itself were still major causes of death, reinforcing infection as an important part of the overall burden. Several case reports illustrated less common complications affecting the mouth and throat, the eyes, and the nails, showing how widely the disease and its treatments can show up in the body. [3] [4] [5] [6]

In Finland (2007 to 2021), median overall survival was 7.3 years and survival improved when comparing earlier and later time periods. The report also described healthcare resource use and comorbidities, although details were not provided in the summary. Importantly, infections were listed among major causes of death, which helps frame why infection risk is often discussed alongside Waldenstrom itself. [3]

One report combined a single patient story with an exploratory database analysis focused on invasive fungal infections during Bruton tyrosine kinase inhibitor (BTKI) therapy such as ibrutinib and zanubrutinib. In the database analysis, aspergillosis was uncommon but not vanishingly rare (0.5% to 1.9% across BTKIs in that dataset), while mucormycosis was reported as very rare (under 0.1%). Corticosteroid use was common among affected patients, and the case example described a patient on zanubrutinib and prednisone who developed dual fungal infection. [7]

Several single-patient reports highlighted rare or easily missed problems. One described a rapidly enlarging tongue-base mass that turned out to be transformation to diffuse large B-cell lymphoma, with initial response to R-CHOP chemotherapy but then an early relapse in the brain. Another described eye changes (immunogammopathy maculopathy with macular schisis) where imaging suggested a masquerade of typical swelling patterns, with suspicion that monoclonal protein deposition was involved. [4] [5]

Other case reports focused on organ involvement and treatment side effects. A patient with IgG-type lymphoplasmacytic lymphoma (a close relative diagnosis) developed kidney dysfunction from light chain deposition disease, confirmed on kidney biopsy and accompanied by a MYD88 mutation in bone marrow. Another report described brittle, splitting nails after 9 months of ibrutinib, presenting a tangible quality-of-life issue that can occur during long-term therapy. [8] [6]

For patients and caregivers, these reports mainly add awareness of the range of complications that can occur, rather than providing new standard steps to follow. The nationwide data suggest that infections remain an important part of the real-world picture even as survival improves, and the BTKI-focused analysis gives a rough estimate that aspergillosis occurs in a small percentage of BTKI-treated patients in that database, with mucormycosis much rarer. The case reports show that unusual symptoms affecting swallowing, vision, or nails can sometimes be related to Waldenstrom or its treatments, while the kidney report involved a related lymphoma of the IgG type rather than Waldenstrom itself. Because these are single patients, they cannot tell how often this happens or who is most at risk. [3] [4] [5] [8] [6]