Rhabdomyosarcoma of the Middle Ear and Mastoid in Children: Experience of the Beijing Children's Hospital-BCH.

Abstract

Objectives: To conduct a retrospective analysis of the clinical characteristics and prognosis of rhabdomyosarcoma of the middle ear and mastoid (MERMS) in children.

Methods: Treatment and outcome of 37 children with MERMS from Beijing Children's Hospital (July 2016-April 2023) were evaluated.

Results: The median age of this cohort was 54 months. Initially, 9 children were misdiagnosed with otitis media and/or granulomas, whereas 11 underwent anti-infective therapy. The disease manifested with a high level of local aggressiveness (T2; 83.8%), often accompanied by meningeal invasion (MI; 27 of 37), encompassing cranial base bone erosion (CBBE; 27 of 27), intracranial extension (ICE; 14 of 27), and cranial nerve paralysis (CNP; 22 of 27), with a predominance of facial nerve involvement in CNP cases. The primary treatment modality for this region was a combination of radiation and chemotherapy. The early response to neoadjuvant chemotherapy emerged as a prognostic factor, significantly impacting 5-year event-free survival (EFS) and overall survival (OS): complete response (CR), 85.7 and 100%; partial response (PR), 43.7 and 65.2%; and progressive disease/stable disease (PD/SD), 16.7 and 16.7% (p = 0.019 and 0.001, respectively). A total of 13 patients passed away, with 4 fatalities attributed to the dissemination of tumor cells in the cerebrospinal fluid and 9 resulting from intracranial progression that impacted the central nervous system. The 5-year OS and EFS were (67.1 ± 7.8%) and (51.1 ± 9.1%), respectively.

Conclusion: MERMS is a highly aggressive malignancy with complex clinical manifestations and frequent cranial nerve involvement. Early recognition, aggressive multimodal treatment, and close monitoring for treatment response are crucial for improving survival outcomes.