Long-term survival following additive radiotherapy in patients with atypical teratoid rhabdoid tumors.
BACKGROUND
Atypical teratoid rhabdoid tumor (ATRT) is a highly aggressive disease of embryonic origin accounting for <5% of all pediatric central nervous system (CNS) tumors.


METHODS
We describe a series of five cases of CNS ATRT. The first three patients underwent subtotal tumor resection. Gross total resection of the tumor was achieved in the fourth and fifth patients. Only 4 patients received chemotherapy, whereas all 5 patients received additive radiotherapy (RT). The latter included three dimensional (3D) conformal RT or intensity modulated RT (IMRT) with a median dose of 54 Gy (range 50.4-59.0 Gy) applied in daily fractions of 1.8 Gy. The median interval between surgery and RT was 5 months (range 2-11 months).


RESULTS
Two months after completion of RT, 4 patients had achieved complete radiologic remission. The median event-free survival period was 46 months (range 10-90 months). However, the first patient died 17 months after developing an out-of-field recurrence. The third patient developed a recurrence 11 months after salvage RT. The other 3 patients (cases 2, 4, and 5) remain alive with no evidence of disease 59, 46 and 90 months after therapy, respectively.


CONCLUSIONS
Overall, the 5 patients survived for a median of 48 months (range 25-90 months) from the time of initial diagnosis and they tolerated the RT well, without severe acute or late onset toxicities. The results imply a potential survival gain after irradiation at acceptable toxicity level.
Radiation oncology department, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, Germany. Khaled.Elsayad@uni-muenster.de.
Khaled
K
Elsayad
Radiation oncology department, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, Germany.
Jan
J
Kriz
Radiation oncology department, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, Germany.
Laith
L
Samhouri
Radiation oncology department, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, Germany.
Uwe
U
Haverkamp
Pediatric oncology department, University Hospital Münster, Münster, Germany.
Ronald
R
Straeter
Neurosurgery department, University Hospital Münster, Münster, Germany.
Walter
W
Stummer
Radiation oncology department, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, Germany.
Hans Theodor
HT
Eich
D000368:Aged; D002648:Child; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D018714:Radiotherapy, Adjuvant / Q000401:mortality / Q000706:statistics & numerical data; D020266:Radiotherapy, Conformal / Q000401:mortality* / Q000706:statistics & numerical data; D018335:Rhabdoid Tumor / Q000175:diagnosis / Q000401:mortality* / Q000532:radiotherapy*; D012307:Risk Factors; D015996:Survival Rate; D013724:Teratoma / Q000175:diagnosis / Q000401:mortality* / Q000532:radiotherapy*; D016896:Treatment Outcome
ATRT; Central nervous system; Children; Intensity-modulated radiotherapy; Tomotherapy; Toxicity