De-escalated Radiotherapy for Advanced Stage Wilms" Tumor
Ayşenur ELMALI1,Sezin YÜCE SARI2,Canan AKYÜZ3,Melis GÜLTEKIN2,Bilgehan YALÇIN3,Burça AYDIN3,Ali VARAN3,Saniye EKINCI4,Murat GÜRKAYNAK2,Tezer KUTLUK3,Ferah YILDIZ2
1Deparment of Radiation Oncology, Elazığ Fethi Sekin City Hospital, Elazığ-Türkiye
2Deparment of Radiation Oncology, Hacettepe University Faculty of Medicine, Ankara-Türkiye
3Deparment of Pediatric Oncology, Hacettepe University Faculty of Medicine, Ankara-Türkiye
4Deparment of Pediatric Surgery, Hacettepe University Faculty of Medicine, Ankara-Türkiye
DOI : 10.5505/tjo.2022.3786 OBJECTIVE
Survival rates have dramatically improved in Wilms" tumor (WT) with multimodal treatment. Herein, we aimed to compare the efficacy of 9?10.8 Gy flank irradiation or whole abdominal irradiation (WAI) in patients with WT treated in a single tertiary treatment center.

This study includes 42 patients with a unilateral or bilateral WT with a local Stage III disease who received a low-dose (10.8 Gy) or lower-dose (9 Gy) flank radiotherapy (RT) or whole abdominal irradiation between 1998 and 2018. Patients had undergone either upfront surgery followed by adjuvant chemotherapy (CXT) or neoadjuvant CXT followed by surgery. Patients with lung metastasis without a complete response to CXT also received whole lung irradiation (WLI) of 9?12 Gy.

The disease was staged as III in 22, IV in 12, and V in nine patients, respectively. After a median follow-up of 75 months, the 2-and 5-year overall survival, locoregional relapse-free survival, and distant metastasisfree survival rate was 92% and 79%, 87% and 76%, and 75% and 69%, respectively. None of these survival rates were significantly different among 9 Gy and 10.8 Gy doses. Among patients receiving WLI, the lung relapse rate was also similar between <12 Gy and 12 Gy of irradiation. Late toxicity was observed in 4 (10%) patients as scoliosis, cardiac dysfunction, renal injury with hypertension, and short stature in each.

De-escalated RT of 9 Gy to the flank or abdomen does not compromise oncologic outcomes in patients with a local Stage III WT. Keywords : De-escalated treatment; radiotherapy; Wilms