Therapy-related second malignant neoplasms on top of neuroblastoma: frequency, types and risk factors.

OBJECTIVES

The aim of the study was to evaluate the long-term effect of multi-modal, risk-based treatment protocols on the development of treatment-related secondary malignant neoplasm (SMN) in patients during or after treatment of Neuroblastoma.

MATERIAL AND METHODS

This retrospective study included all patients with neuroblastoma treated at Children's Cancer Hospital-Egypt from July 2007 to December 2022.

RESULTS

24 out of 2290 patients (1%) received risk-tailored multimodal treatment protocols suffered from either hematological (21/24) or solid (3/24) treatment-related SMN during or after treatment of their primary neuroblastoma disease. Age at neuroblastoma diagnosis ranged from 6 mo to 9.5 y (median age: 2 y) with male to female ratio of 1.2:1. Time to development of hematological treatment-related SMN was 14 mo to 8.3 y (mean: 3.7 y) versus 5.5-9.2 y (mean: 7.6 y) for solid treatment-related SMN. High cummulative doses of ifosfamide, cyclophosphamide, and etoposide were most frequently encountered among study patients.

CONCLUSIONS

Patients with neuroblastoma are at more risk of developing hematological than solid treatment-related SMN after relatively longer duration for latter compared to former tumor subtypes. High-risk treatment regimens and higher cumulative doses of alkylating agents and Topoisomerase-II inhibitors are likely associated with increased risk of treatment-related SMN.