Tumor Characteristics in Patients With Paraneoplastic Neurological Syndromes (PNS)

Paraneoplastic neurological syndromes (PNS) are immune-mediated complications of cancer that can affect any part of the central or peripheral nervous system. PNS occurs at the intersection between immune system and the tumor, where a combination of genetical and environmental factors may play a role. Mechanisms leading to immune tolerance breakdown and autoimmunity in PNS remain largely unknown, and this reflects in an unsatisfactory repertoire of treatments available. Moreover, a better understanding of the biological mechanisms underlying PNS would allow a more precise identification of the modalities that permit PNS patients to have a better oncological prognosis than cancer patient without PNS, with obvious repercussions in clinical oncology. To this effect, an extremely innovative approach involves directly exploring the tumoral tissue of patients suffering from specific PNS via genomic and transcriptomic analysis. The study team hypothesizes that antigen ectopic expression by tumour cells may contribute to the generation of PNS. In the present study, the investigators will analyze the salient features of tumors associated with PNS, namely the histological and immune cells infiltrate characteristics, their transcriptomic profile, and mutational status of involved antigens.