Roundup and Multiple Myeloma — The Lesser-Known Roundup Cancer

When most people hear "Roundup cancer," they think Non-Hodgkin Lymphoma. The verdicts that made the headlines — Johnson, Hardeman, Pilliod — were NHL cases. But the cancer that shows up most often in commercial applicators and longtime farmers in our intake calls is something else: Multiple Myeloma.

What Is Multiple Myeloma?

Multiple Myeloma is a cancer of plasma cells — the white blood cells in your bone marrow that make antibodies. When plasma cells become cancerous, they crowd out normal bone marrow cells, weaken bones, damage kidneys, and produce abnormal antibodies that can be detected on a blood test as a "monoclonal protein" or "M-spike."

Like Non-Hodgkin Lymphoma, Multiple Myeloma is a cancer of the immune system. Unlike NHL, it almost never forms a solid tumor. The diagnosis usually comes from a combination of blood work (high calcium, low blood counts, kidney problems, M-spike), imaging (bone lesions), and bone marrow biopsy.

The Science Linking Glyphosate to Multiple Myeloma

The same body of research that connects glyphosate to NHL also points to Multiple Myeloma. Several large epidemiological studies of farmers and pesticide applicators have found elevated rates of MM among those with high glyphosate exposure:

• The Agricultural Health Study — a large prospective cohort of licensed pesticide applicators in Iowa and North Carolina — reported a positive association between glyphosate use and Multiple Myeloma in earlier analyses, with relative risks elevated in the highest exposure tertile.
• A 2008 case-control study in Sweden (Eriksson et al.) reported a significant association between glyphosate exposure and B-cell lymphomas, with Multiple Myeloma included in the broader lymphoid malignancy category.
• The 2015 IARC monograph on glyphosate, while focused on NHL, noted "limited evidence" of carcinogenicity that included lymphoid cancers more broadly — a category that includes Multiple Myeloma.

The biological mechanism is consistent: glyphosate disrupts immune cell signaling, causes oxidative DNA damage, and chronically activates B-cell lineages — the same cell line from which plasma cells (and Myeloma) arise.

Why Farmers and Applicators Are the Core MM Population

Multiple Myeloma is strongly associated with occupational pesticide exposure. The patients we see most frequently with MM-and-Roundup claims include:

• Row-crop and orchard farmers who sprayed glyphosate on hundreds of acres per year, often without respirators, for decades.
• Groundskeepers and landscapers at golf courses, parks, cemeteries, school districts, and HOAs — the same long-cumulative-exposure profile in a different setting.
• Commercial pesticide applicators who held state licenses and used Roundup as part of large-scale weed-management contracts.
• Long-time nursery and greenhouse workers who mixed and applied glyphosate in enclosed spaces.

Home Roundup users with MM diagnoses can still have viable claims, but the exposure histories are usually different in scale. Occupational claims are the most straightforward to investigate.

How Multiple Myeloma Cases Compare to NHL Cases

Latency

Multiple Myeloma often takes longer to develop than NHL after the start of exposure — commonly 10 to 30 years. That means MM claims often involve exposure that began in the 1980s or 1990s and a diagnosis in the 2010s or 2020s.

Smoldering and Precursor States

MM has a recognized precursor state called Monoclonal Gammopathy of Undetermined Significance (MGUS), and an intermediate state called Smoldering Multiple Myeloma. Patients sometimes have MGUS for years before progressing. In our review, we account for the full disease arc — not just the date the diagnosis became "Multiple Myeloma."

Damages

MM treatment is intense: chemotherapy, immunotherapy, stem-cell transplant for eligible patients, ongoing maintenance regimens, and management of bone, kidney, and infection complications. The damage profile is often as serious as in NHL cases — sometimes more so.

The Litigation Picture for Multiple Myeloma Claims

Multiple Myeloma claims have always been part of the federal Roundup MDL (In re: Roundup Products Liability Litigation, MDL No. 2741, Northern District of California). The litigation framework that won the NHL bellwethers is the same one used in MM cases: defective design, failure to warn, fraud, and concealment.

Bayer's 2020 settlement included some MM claims and excluded others. The litigation has continued past the 2020 framework, and new MM cases are still being filed in 2026 — both in the federal MDL and directly in state courts where venue, law, and discovery rules may be more favorable.

Do You Qualify?

The general qualification framework we apply to MM cases is:

• Diagnosis. Multiple Myeloma confirmed by bone marrow biopsy and oncology workup. Earlier MGUS or Smoldering MM stages may be included if they progressed.
• Exposure. Documented use of Roundup or other glyphosate-based herbicides for an extended period — commonly years, often decades.
• Timeline. A latency period consistent with what the literature describes, generally 10+ years from start of exposure to diagnosis.
• Statute of limitations. Your state's filing window is still open. See our companion piece on whether you can still sue Monsanto in 2026.

Bottom Line

Multiple Myeloma is the underclaimed Roundup cancer. The science is part of the same body of evidence that supports NHL cases. The patients are commonly farmers, groundskeepers, and commercial applicators with long, well-documented exposure histories. The litigation framework is the same MDL that has produced NHL verdicts. If you or a family member has been diagnosed with Multiple Myeloma and used Roundup heavily for years, the next step is a free case review. Herb Borroto, M.D., J.D., reviews the pathology and oncology records personally. There is no fee unless we recover for you.