ESTRO 2023 - Abstract Book

S283

Sunday 14 May 2023

ESTRO 2023

25 paediatric patients and 19 TYA patients met the inclusion criteria (Table 1). Of the 44 patients, 12/44 (27%) had a prophylactic RIG placed and 1/44 patients required NGT insertion during PBT. 9/12 (75%) patients used their prophylactic RIG during PBT. At 6 weeks post-PBT, 2 patients remained on enteral feeds. All patients with 12 months follow-up (46%) no longer needed enteral feeding. The oral cavity mean dose and V30Gy were significantly associated with increased risk of enteral feeding. No patients with an oral cavity mean dose <28.4Gy(RBE=1.1) required enteral feeds. There was also a higher risk in patients with oral cavity V30Gy 45%, stage T4 tumours, and tumour at diagnosis >76cc (Figure 1 and 2). Other statistically significant risk factors for enteral feeding were increased parotids mean dose (p=0.029) and CTV_Low volume (p=0.002). There was also a higher risk in patients with primary midline tumours (p=0.097).

Table 1: Patient Characteristics Patient Characteristic

No.

Sex

1.

Male

20 24

•

Female

Age Group •

25 19

Paediatric

•

TYA

Primary Tumour Location •

10

Base of Skull

• • • • • • • • • • • • • • • • • • • •

1 8 4 8 2 6

Mandible

Nasopharynx

Neck

Oral cavity/Hard Palate/Soft Palate 5

Orbit

Parotid

Sino-nasal/Nasal

Histopathology •

21 10

Rhabdomyosarcoma/Ewing sarcoma

Other types of sarcoma

9 1 1

Carcinoma Meningioma

Olfactory neuroblastoma

Complex mixed and stromal tumours 2

T stage

6 6

T1 T2 T3 T4

10 11 11 22 10 22

Not recorded

N stage

N0 N+

Not recorded

Chemotherapy •

31 13

Yes

•

No