Clinical Utility of Complex Assessment With Evoked Potentials in Acute Lymphoblastic Leukemia Survivors: Comparison of Various Treatment Protocols

Abstract

Background: One of the largest success in a pediatric hematology is a prominent improvement of survival in acute lymphoblastic leukemia (ALL). Simultaneously, it encourages to focus on long-term effects of the treatment such as neurotoxicity. One of the few diagnostic methods that allow an objective assessment of sensory organization are evoked potentials (EP).Methods: We analyzed the group consisted of 167 ALL long-term survivors, aged 4.9-28.4 years, without auditory, visual and sensory deviations. Patients were treated with New York (NY, n=35), previous modified Berlin-Frankfurt-Münster (pBFM, n=47) and BFM95 (n=85) protocols. In order to assess the impact of radiotherapy on recorded EP, a joint analysis of NY and pBFM groups was performed. The control group consisted of 35 patients, aged 6-17 years. The analyzed patients underwent a complex assessment with visual EP (VEP), somatosensory EP (SEP) and brainstem auditory EP (BAEP) in accordance with current standards.Results: ALL treatment contributed to the shortening of wave I latency (1.59 vs 1.90, P=0.003) and prolongation of I-III (2.23 vs 2.04, P=0.004) and I-V (4.57 vs 4.24, P=0.002) interwave latencies in BAEP. A significant effect was also noticed in P100 (106.32 vs 101.57, P<0.001) and N135 (151.42 vs 138.22, P<0.001) latencies for VEP and N18 amplitude (3.24 vs 4.70, P=0.007) and P25 latency (21.32 vs 23.39, P<0.001) for SEP. The distribution of abnormalities between protocols was similar in BAEP (NY - 68.6%, pBFM - 61.7%, BFM95 - 69.4%, P=0.650), VEP (NY - 68.6%, pBFM - 42.5%, BFM95 - 58.3%, P=0.053) and significantly different for SEP (NY - 62.9%, pBFM - 36.2%, BFM95 - 53.0%, P=0.045). The harmful effect of radiotherapy was most clearly marked in numerous disturbances of SEP parameters.Conclusions: The presented analysis indicates a high frequency of subclinical abnormalities in EP regardless of the analyzed protocol. To our knowledge current study is the largest and one of the most complex research examining the role of EP in ALL patients. The obtained results indicate the possibility of using a single, objective and non-invasive measurement of EP in ALL survivors in order to stratify the risk of developing sensory abnormalities in adulthood.

Clinical utility of complex assessment with evoked potentials in acute lymphoblastic leukemia survivors: comparison of various treatment protocols

“…Third, in the current study we analyzed ALL protocols used in clinical practice in the past. However, only such an analysis made it possible to verify the impact of radiotherapy on EP, which was one of the objectives of our studies [ 27 ].…”