Abstract
Purpose :
Although reduced relative to systemic chemotherapy, IAC is often cited to carry systemic side effects, most notably neutropenia. However, studies regarding the risk of neutropenia remain limited and unstandardized. This study aims to estimate the frequency and grade (1-4) of neutropenia following IAC, as well as identify risk factors associated with development of neutropenia.
Methods :
This was a retrospective chart review of patients with unilateral or bilateral retinoblastoma treated with IAC at a single quaternary care center from 2013 to 2021. The current analysis included all IAC cycles administered during the study period. Following each IAC, complete blood counts were collected within 10-12 days and repeated until absolute neutrophil count (ANC) reached >1000 cells/µl. The primary outcome was the minimum ANC value that developed, and linear regression analyses were used to identify associations between baseline variables and the outcome.
Results :
A total of 58 eyes of 43 patients with retinoblastoma were treated with 176 cycles of IAC. The median number of IAC cycles received per eye was 3 (range, 1-7). The mean minimum ANC was 1355.0 ± 866.6 cells/µL and occurred 12.6 ± 5.4 days following IAC administration. The grade distribution of post-IAC neutropenia was 34 (19.3%), 29 (16.5%), 34 (19.3%), 40 (22.7%), and 21 (11.9%) for grades 0, 1, 2, 3, and 4, respectively. Younger age was significantly associated with neutropenia following IAC.
Conclusions :
In this study, the prevalence of any (grade ≥1) and severe (grade ≥3) neutropenia after IAC were 81.7% and 34.6%, respectively. These rates may be higher than previously reported, though methods of measurement vary across studies (e.g., prevalence by patient vs IAC cycle). These findings have implications for risk assessment and post-IAC laboratory monitoring for neutropenia.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.