Abstract 750P
Background
Adolescents and Adults Rhabdomyosarcoma is a rare entity with a reported poor prognosis compared to its paediatric counterpart; hence, it needs further exploration of the clinicopathological features and treatment outcomes.
Methods
This is a retrospective analysis of the prospectively collected data of Histopathologically confirmed Rhabdomyosarcoma (RMS) patients over the age of 14 who registered at our institution between 2014 and 2021. They were analysed for age, histopathological subtype, site of primary, distant metastasis at diagnosis, Children's Oncology Group (COG) risk group, PAX-FKHR gene fusion status, type of treatment (operative versus non operative), response to primary therapy, overall survival (OS), event-free survival (EFS), and treatment-related toxicities.
Results
The median age of 57 patients was 23 (range 15-63 years), including 38 (66.7%) males. 27 (47.4%) had distant metastasis at diagnosis, and 44 (77.2%) had primary at an unfavourable site. ARMS 19 (33.9%) followed by ERMS 11(19.3%) were the common pathological subtypes. 47 (82.5%) patients had tumour size ≥ 5cm. Majority belonged to COG High-risk group 27 (47.3%). PAX-FKHR gene fusion was seen in 9 out of 18 evaluable patients. Of the 45 patients treated with curative intent, 23 (51.1%) underwent primary tumour resection and 18 (40%) were treated with definitive radiation therapy. 35 (75.8%) patients were offered neoadjuvant chemotherapy, with an overall response rate of 29 (64.4%). 32 (88.8%) patients had grade 3/4 toxicity in perioperative chemotherapy, mostly haematological, including febrile neutropenia in 28 (77.7%). Whereas 26 (72.2%) patients required dose modification in perioperative therapy. At a median follow-up of 24 months and 38 events, the median event-free survival (EFS) was 18 (95% CI, 14.8 - 21.2) months, while the median overall survival (OS) was 24 (95% CI, 18.7 - 29.2) months.
Conclusions
Adolescent and adult RMS patients need a risk-based multimodality treatment approach with proper dose modification as required as they develop significant toxicity. Further prospective collaborative studies are required to improve outcomes in this cohort.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.