ESTRO 2024 - Abstract Book

S1209

Clinical - Head & neck

ESTRO 2024

Results:

Regarding Cochlea-sparing, no citation was selected. 11 works were selected for hippocampal sparing: they were published between 2015 and 2021 and accounted for 753 patients treated with prophylactic WBRT or for metastases who underwent the sparing procedures. Neurocognitive functions were evaluated with a heterogeneous range of tests, with the HVLT-R, TMT A and B, Cowa test and MME as the most used ones. For Scalp sparing, only 3 papers of the initial 160 ones were selected: one retrospective study and two prospective ones, published from 2014 to2015, accounting for a total of 65 patients. An important heterogeneity in terms of scalp definitions, CTVs, used techniques and doses, and the methods and scales used to evaluate the clinical efficacy of scalp sparing differ in each experience (The SALT score, the EORTC-QLQ-BN20, or a simple observational comparison) was observed. The metanalysis could be conducted only for the paper focusing on the hippocampal sparing procedures, with only 5 papers meeting the inclusion criteria. The heterogeneity of the studies was high (Cochran Q test 208.3, df 4, p<0.001, I2 index 98.08%, H2M index 51.08). For this reason, we opted for random effect models DerSimonian Leard (DL), Maximum Likelihood (ML), and Profile Likelihood (PL), which provided widely overlapping results, as can be seen from the forest plot (Figure 1).

Conclusion:

A high heterogeneity in terms of hippocampal-, cochlea-, and scalp-sparing was registered among the studies; our findings indicate the need for further studies to explore this issue.in particular, although the data show an average protective effect of Hippocampal Avoidance on cognitive performance, the meta-analysis, based on the available studies, is unable to demonstrate its significance.

Keywords: WBRT, Sparing, Systematic Review