Patients with small cell lung cancer (SCLC) and type 1 antineuronal nuclear or “Hu” antibody (ANNA1/Hu-IgG)–related paraneoplastic neurological syndromes (PNS) may experience longer survival, according to the results of a study published in Journal of Neurology.
Additionally, in those with ANNA1/Hu-IgG–related PNS specifically, faster progression of disability and a higher risk for mortality was noted with limbic encephalitis at onset, which could be a modifiable factor for early disease intervention.
“Our description of [PNS] can help us educate patients about what they can expect, as well as guide clinicians about treatment and surveillance priorities,” said first author Kimberly DiMauro, DO, also a staff neurologist with the Mellen Center. “In addition, the suggestion that paraneoplastic autoimmunity is associated with survival outcomes may have implications for understanding the pathophysiology of these disorders.”
Background and Study Methods
Researchers sought to further understand the association between ANNA1/Hu-IgG–related PNS and SCLC by evaluating factors associated with disability and survival in ANNA1/Hu-IgG–related PNS and comparing the survival of these patients with those with SCLC.
“Patients with [PNS] are often understudied and underrepresented in neuroimmunology research due to the rarity of their disease,” said senior study author Amy Kunchok, MD, PhD, staff neurologist in Cleveland Clinic’s Mellen Center for Multiple Sclerosis Treatment and Research. “There is a great need to study patients with PNS to understand their disease course and factors that influence it. We also need better treatments to minimize the disability that they experience.”
They conducted a single-center study of 45 patients with ANNA1/Hu-IgG–related PNS. They estimated time to mortality, wheelchair dependence, and modified Rankin Scale. Secondary analyses looked at the comparison between patients with ANNA1/Hu-IgG–related PNS and those with SCLC, adjusting for age, sex, cancer stage, and treatment.
Key Findings
Disability and survival were associated with clinical phenotype from the onset of the disease. Limbic encephalitis had a higher hazard ratio (HR) of modified Rankin Scale score above 2 (HR = 6.84; 95% confidence interval [CI] = 2.12–22.04; P = .001) and a higher risk of death (HR = 2.44; 95% CI = 1.05–5.66; P = .039).
In patients with SCLC, patients who also had ANNA1/Hu-IgG–related paraneoplastic neurological syndromes (n = 26) had a 41% lower risk of death compared with patients with SCLC only (HR = 0.59; 95% CI = 0.37–0.96; P = .033).
“Research using a larger cohort from multiple institutions would help answer the question of whether increased survival is an antitumor effect inherent to the syndrome or a result of lead-time bias—or if there are elements of both,” Dr. DiMauro said.
DISCLOSURES: For full disclosures of the study authors, visit springer.com.
