Outcomes for children with recurrent/refractory atypical teratoid rhabdoid tumor: A single‐institution study with molecular correlation

Abstract Background Survival data for recurrent pediatric atypical teratoid rhabdoid tumor (ATRT) and its association to molecular groups are extremely limited. Methods Single‐institution retrospective study of 64 children less than 21 years old with recurrent or treatment‐refractory (progressive disease [PD]) ATRT treated at St. Jude Hospital from January 2000 to December 2020. Demographic, clinicopathologic, treatment, molecular grouping (SHH, TYR, and MYC) and germline data were collected. Progression‐free survival (PFS2: time from PD to subsequent first progression) and overall survival (OSpostPD: time from PD to death/last follow‐up) were estimated by Kaplan–Meier analysis. Results Median age at and time from initial diagnosis to PD were 2.1 years (range: 0.5–17.9 years) and 5.4 months (range: 0.5–125.6 months), respectively. Only five of 64 children (7.8%) are alive at median follow‐up of 10.9 (range: 4.2–18.1) years from PD. The 2/5‐year PFS2 and OSpostPD were 3.1% (±1.8%)/1.6% (±1.1%) and 20.3% (±4.8%)/7.3% (±3.5%), respectively. Children with TYR group ( n = 10) had a better OSpostPD compared to those with MYC ( n = 11) (2‐year survival estimates: 60.0% ± 14.3% vs. 18.2% ± 9.5%; p = .019), or those with SHH ( n = 21; 4.8% ± 3.3%; p = .014). In univariate analyses, OSpostPD was better with older age at diagnosis ( p = .037), female gender ( p = .008), and metastatic site of PD compared to local or combined sites of PD ( p < .001). Two‐year OSpostPD for patients receiving any salvage therapy ( n = 39) post PD was 33.3% ± 7.3%. Conclusions Children with recurrent/refractory ATRT have dismal outcomes. Older age at diagnosis, female gender, TYR group, and metastatic site of PD were associated with relatively longer survival in our study.