People with monoclonal gammopathy of undetermined significance (MGUS), a rarely diagnosed condition that can progress to myeloma, go to the hospital twice as often as people without the condition, new research suggests. This may be helpful in identifying people with MGUS and, by extension, aid in early diagnosis of myeloma.
The research was presented in Belfast at the 2019 National Cancer Research Institute (NCRI) Cancer Conference in a presentation titled, “Hospital activity before and after diagnosis of monoclonal gammopathy of undetermined significance (MGUS).”
“MGUS is a benign condition that doesn’t have obvious symptoms. It is usually only diagnosed incidentally when doctors are investigating other problems, so around 90% of cases remain undiagnosed,” co-investigator Maxine Lamb, PhD, a research fellow at the University of York, U.K., said in a press release.
“In the majority of people, this condition doesn’t progress to cancer. However, virtually all people with myeloma, as well as a proportion of patients with some types of lymphoma, had MGUS before their cancer developed. That’s why we’re interested in spotting this condition,” she said.
Lamb and other researchers analyzed data from the U.K.’s Haematological Malignancy Research Network. This included two groups of people: 2,219 people with confirmed MGUS and 22,190 controls who did not have MGUS, but were similar to patients in terms of demographic details such as age, sex, and geographic residence.
Researchers found that in the three years before they were diagnosed with MGUS, patients went to the hospital at an average rate of 30.6 visits per 100 people per month. That is a significantly higher rate than the 20.9 visits per 100 people per month seen in controls.
Further analysis revealed that this was driven primarily by outpatient hospital visits (when the person is not admitted to the hospital), with average rates of about 31 and 16 visits per 100 people per month in the patients and controls, respectively. In other words, patients had outpatient hospital visits nearly twice as frequently as controls.
Additionally, compared to controls, patients were 5.5 times more likely to visit a nephrology clinic, 3.7 times more likely to visit a rheumatology clinic, and 2.4 times more likely to visit a dermatology clinic in the years preceding diagnosis. Patients also visited orthopedic clinics more frequently.
Notably, this pattern of hospital visitation was not observed in other conditions that are considered precursors to blood cancers, such as monoclonal B-cell lymphocytosis, suggesting it may be unique to MGUS. Presumably, this is because people with the disease are at an increased risk of complications including autoimmune disorders, fractures and infections, which has been demonstrated in previous studies. However, this research doesn’t prove that.
Still, the finding may help identify people who are more likely to have MGUS — and subsequently develop myeloma.
“Once someone is diagnosed with MGUS they are monitored for signs that that they are developing myeloma,” Lamb said. “This study suggests a possible way to spot more cases of MGUS and this could give us the opportunity to try to diagnose more cases of myeloma, and some types of lymphoma, at an earlier stage.”
Gordon Cook, PhD, a professor at the University of Leeds and chair of the NCRI myeloma sub-group, was not involved in the study, but added: “We believe that all cases of myeloma are preceded by MGUS but very few MGUS patients develop myeloma. Spotting MGUS early and finding those at greatest risk of developing myeloma is essential if we are to improve outcomes. However, it’s important to remember that MGUS itself does not require treatment and the majority of people found to have MGUS will not go on to develop myeloma.”