Pediatric Cancer

PV QA 3 - Poster Viewing Q&A 3

TU_25_3110 - Predictors of Facial Asymmetry in Childhood and Young Adult Head and Neck Sarcoma Treated with Radiation Therapy

Tuesday, October 23
1:00 PM - 2:30 PM
Location: Innovation Hub, Exhibit Hall 3

Predictors of Facial Asymmetry in Childhood and Young Adult Head and Neck Sarcoma Treated with Radiation Therapy
S. Acharya, S. C. Kaste, J. Becksfort, C. H. Hua, T. E. Merchant, and M. Krasin; St. Jude Children's Research Hospital, Memphis, TN

Purpose/Objective(s): The vomer and condyle represent important growth centers for the midface and ramus, respectively. The purpose of this study was to determine whether radiation (RT) dose to either structure is correlated with degree of facial asymmetry in childhood and young adult head and neck (HN) sarcoma treated on a phase II trial of image-guided RT.

Materials/Methods: As a part of the phase II protocol, all patients underwent head CT seven years post-treatment to assess for changes in bone density and facial symmetry. In order to quantify facial asymmetry, a mirror image of the anterior head CT was superimposed on the original. The volume of non-overlap between the original and mirror image was calculated and defined as facial volume loss. Patient and tumor characteristics as well as vomer and condyle dosimetric parameters were correlated with the degree of facial volume loss using Fisher’s exact and Wilcoxon rank-sum tests.

Results: From 2013 to 2016, 17 HN sarcoma protocol patients underwent head CTs seven years post-treatment. Median treatment age was 7 years (range: 1 – 23 years). Tumor locations were: midline 5 (29%), lateral 9 (53%), and midline and lateral 3 (18%). Extent of surgery was greater than biopsy in 6 (35%) and biopsy alone in 11 (65%). The median difference between the maximum point dose to a patient’s right and left condyle was 8.7 Gy (range: 1 – 30.9 Gy). The median difference between the maximum point dose to a patient’s right and left side of vomer was 0.5 Gy (range: 0 – 34.3 Gy). All patients experienced some degree of facial volume loss (median loss: 31.5 cc, range: 12.23 – 111.35 cc). Facial volume loss of <20 cc was associated with midline tumors (p=0.015) and smaller differences between right and left condylar maximum dose (p=0.023). Facial volume loss of >60 cc was associated with greater than biopsy extent of resection (p=0.053).

Conclusion: Non-midline tumor location, greater differences in right and left condylar dose and greater extent of surgery might be associated with facial asymmetry seven years after completion of RT. Further follow-up of the remaining HN sarcoma patients on protocol will be needed to verify this preliminary result.

Author Disclosure: S. Acharya: None. J. Becksfort: None. C. Hua: None. T.E. Merchant: None. M. Krasin: None.

Sahaja Acharya, MD

Disclosure:
Employment
St Jude Children's Research Hospital: Assistant Member: Employee

Presentation(s):

Send Email for Sahaja Acharya


Assets

TU_25_3110 - Predictors of Facial Asymmetry in Childhood and Young Adult Head and Neck Sarcoma Treated with Radiation Therapy



Attendees who have favorited this

Please enter your access key

The asset you are trying to access is locked. Please enter your access key to unlock.

Send Email for Predictors of Facial Asymmetry in Childhood and Young Adult Head and Neck Sarcoma Treated with Radiation Therapy