Not all Guillain-Barré cases are associated with infection, and studies have suggested a link between the rare disorder and certain cancers, including lymphomas.
Certain cancers, such as lymphomas, may increase the risk of new-onset Guillain-Barré syndrome, according to a study published in Neurology, the medical journal of the American Academy of Neurology.
Guillain-Barré is a rare disorder that frequently occurs after an infection; however, half of all patients with Guillain-Barré syndrome did not have a previous infection, explained the authors.
“Previous studies have suggested there may be a link between cancer and Guillain-Barré syndrome, but just how often people develop Guillain-Barré after a cancer diagnosis has not been well-studied,” study author Lotte Sahin Levison, MD, PhD, of Aarhus University Hospital in Denmark, said in a statement. “Our research looked at the population of nearly six million people in Denmark and found that people diagnosed with cancer may have a higher risk of developing Guillain-Barré.”
The authors assessed the association between cancer and Guillain-Barré using a large population-based nationwide study using the Danish Civil Registration System linked to the Danish National Patient Registry. Patients diagnosed with Guillain-Barré between January 1, 1987, and December 31, 2016, and admitted and treated at neurological or pediatric hospital departments were included.
In addition, they assessed diagnoses of all types of cancer occurring from 6 months prior to admission for Guillain-Barré, to 2 months after admission.
A total of 2414 patients with Guillain-Barré were included, as well as 23,909 controls. Among the cases of Guillain-Barré, 2% of patients (n = 49) were diagnosed with cancer during the window between 6 months prior to and 2 months after admission. In comparison, only 0.6% (n = 138) of controls were diagnosed with cancer during the same window.
Among the patients with Guillain-Barré with cancer, 22.4% had cancer originating in the respiratory tract, 16.3% in the lymphatic and hematopoietic tissue, 16.3% in the prostate, and 10.2% in breast.
Overall, people recently diagnosed with cancer had 3.6 times (95% CI, 2.6-5.1) greater risk of developing Guillain-Barré compared with the controls. Even after adjusting for surgery, infections, and other health problems, the risk was still nearly 3 times greater.
People with lymphomas had a risk that was 7 times greater than controls, people with lung or prostate cancers had a 5.5 times greater risk and those with breast cancer had a 5 times greater risk of developing Guillain-Barré.
The authors noted that patients with Guillain-Barré may have been more closely screened for cancer compared with patients without Guillain-Barré, which may have led to some patients with cancer being missed in the control group. In addition, any misclassification of Guillain-Barré, for instance as paraneoplastic neuropathy, may have resulted in a falsely reduced association between cancer and Guillain-Barré.
Despite the findings of the study, the exact pathophysiological mechanisms of developing Guillain-Barré remains unclear. Disturbances to the immune system as a result of a tumor may lead to the development of Guillain-Barré, the authors surmised.
“While our study suggests that people with cancer have a greater risk of developing Guillain-Barré syndrome, it is important that people with cancer know the overall risk of developing Guillain-Barré is still very small,” said Levison. “More research is now needed. Our results suggest that yet unidentified factors present in several types of cancer may contribute to this increased risk.”
Levison LS, Thomsen RW, Sindrup SH, Andersen H. Association between incident cancer and Guillain-Barré syndrome development: a nationwide case-control study. Neurology. Published online March 2, 2022. doi:10.1212/WNL.0000000000200015