P07.15.B NEUROMUSCULAR HIGH-RESOLUTION ULTRASOUND IN PERIPHERAL NEUROTOXICITY OF SYSTEMICALLY TREATED CANCER PATIENTS

Abstract

Abstract BACKGROUND Up to 40 % of cancer patients treated with neurotoxic cytostatic chemotherapies develop treatment-induced peripheral neuropathy. Furthermore, in patients treated with immune checkpoint inhibitors neuromuscular immune-related adverse events (irAEs) are the most common neurological complication. The differentiation between various types of peripheral neurotoxicity, neurological comorbidities and (para-)neoplastic conditions requires experienced clinical and neurophysiological diagnostics within an interdisciplinary team of experts. High-resolution ultrasound (HRUS) is a widely used diagnostic tool for peripheral neuropathies. As there are no generally approved biomarkers of treatment-related neurotoxicity so far, HRUS might extend the repertoire of diagnostic and neuromonitoring methods in patients with neuropathies induced by cytostatic agents, immunotherapy, and targeted therapy. MATERIAL AND METHODS We present the integration of HRUS into a standardized algorithm for suspected peripheral neurotoxicity by characterizing a case series from our neuro-oncological center. We show representative HRUS findings of seven cancer patients (diagnosed with breast cancer, cholangiocarcinoma, colorectal carcinoma, or multiple myeloma) treated with platinum derivates, immune checkpoint inhibitors, bortezomib, or lenalidomide. RESULTS We describe the potential of HRUS independently of a certain cancer treatment regimen and beyond that in patients with both neurological co-morbidities and concomitant neoplastic infiltration of the nervous system. In our retrospective cohort, HRUS revealed partly continuous and partly discontinuous nerve swelling as well as compression syndromes. Moreover, we detected enlargements of dorsal roots and vagus nerve in cancer patients with treatment-induced neuropathies for the first time. In addition, we identified significant discordance between clinical, electrophysiological and HRUS findings and discuss how peripheral neurotoxicity may be amenable to complementary HRUS assessment and neuromonitoring. CONCLUSION At our institution, neuromuscular ultrasound is an integral part of the interdisciplinary algorithm for peripheral neuropathies in systemically treated cancer patients. HRUS expands the neurological tool inventory for cancer patients and accelerates the differentiation of peripheral neurotoxicity, neurological comorbidities, and neoplastic affection of the nervous system in a non-invasive and cost-sparing manner. Our data may help to detect distinct patterns of nerve enlargement as new biomarkers of peripheral neurotoxicity. Thus, we employed our data to conduct a prospective, cross-sectional trial (PARTICIPATE), which has the potential to define the diagnostic relevance of HRUS for patients treated with agents affecting the PNS and its impact on cancer patient care.