A recent study led by Dr. Marta Simó and Dr. Jordi Bruna, principal investigators of the Neurooncology group at Hospital de Bellvitge-IDIBELL-ICO, in collaboration with members of the Functional Lung Unit, such as Dr. Susana Padrones and Dr. Ernest Nadal, was recently published in the journal Neurology.
Funded by the Carlos III Health Institute (ISC III), the study analysed the clinical characteristics, serological biomarkers, and structural brain changes associated with cognitive impairment (CI) in patients with small-cell lung cancer (SCLC). The findings highlight a little-known but common issue among people with cancer and provide new evidence on the underlying mechanisms.
Cognitive impairment: a common reality in lung cancer patients
The study found that 31% of patients already showed symptoms of cognitive impairment at the time of diagnosis. This condition was associated with a localized loss of grey matter in key brain areas related to memory and visual-spatial skills, as well as more diffuse white matter damage. On a serological level, patients showed lower levels of brain-derived neurotrophic factor (BDNF), a protein essential for neuronal survival and plasticity.
After chemotherapy treatment, one-third of patients continued to present cognitive impairment. Furthermore, those with persistent CI had a higher incidence of advanced disease, suggesting a possible association between tumour burden and cognitive decline.
In contrast, only 10% of patients developed de novo cognitive impairment—for the first time—after chemotherapy. This percentage indicates a relatively low incidence of the phenomenon known as “chemo brain,” or chemotherapy-induced cognitive toxicity, which may cause cognitive side effects. According to the study, this phenomenon was uncommon and was mainly associated with smoking, as patients with heavier tobacco use had a higher risk of developing it.
Toward better management of cancer-related cognitive impairment
These findings underscore an underestimated issue that significantly affects the quality of life of people with lung cancer. The identification of biomarkers that can monitor cognitive impairment in these cases could mark a turning point in its clinical management. Moreover, the study opens new lines of research for the prevention and treatment of this disorder, aiming to deepen our understanding of the mechanisms that lead to its development.
Reference article
Simó, M., et al. Cancer-related Cognitive Impairment in Patients With Lung Cancer. Neurology, 2025. DOI: 10.1212/WNL.0000000000213651