Li et al reported 2 models for predicting severe oral mucositis in a patient undergoing chemo-radiation for nasopharyngeal cancer. One model uses the radiation dose based on oral cavity contour. The authors are from Zhejiang Cancer Hospital, Zhejiang Key Laboratory of Radiation Oncology, Quanzhou First Hospital Affiliated to Fujian Medical University, People's Hospital of Maoming, Shanghai Pulmonary Hospital and Hangzhyou YITU Healthcare Technology Co, Ltd.
Patient selection: Chinese adult with nasopharyngeal cancer undergoing chemoradiation
Parameters:
(1) body mass index classification prior to radiation therapy
(2) retropharyngeal lymph node irradiation
(3) oral cavity contour (OCC) as volume percentage of OCC receiving >= 15Gy
(4) oral cavity contour (OCC) as volume percentage of OCC receiving >= 60 Gy
(4) radiation therapy technique
(5) concurrent nimotuzumab
|
Parameter
|
Finding
|
Points
|
|
BMI classification
|
16.5 to 18.49 (1)
|
0.152
|
|
|
18.5 to 22.99 (2)
|
0.304
|
|
|
23 to 24.99 (3)
|
0.456
|
|
|
25 to 29.99 (4)
|
0.608
|
|
|
30 to 39.99 (5)
|
0.76
|
|
retropharyngeal LN
|
none (0)
|
0
|
|
|
unilateral (1)l
|
0.163
|
|
|
bilateral (2)
|
0.326
|
|
volume percent receiving >= 15 Gy
|
|
0.028 * (percent)
|
|
volume percent receiving >= 60 Gy
|
|
0.120 * (percent)
|
|
radiation therapy technique
|
traditional IMRT (1)
|
0.08
|
|
|
TOMO (2)
|
0.16
|
|
concurrent nimotuzumab
|
no
|
0
|
|
|
yes
|
0.097
|
where:
• TOMO = helical tomography radiotherapy
• IMRT = intensity-modulated radiotherapy
risk score =
= SUM(points for all of the parameters) - 4.805
Interpretation:
• A score >= -0.95 is associated with severe oral mucositis (RTOG grade >= 3).
Performance:
• The area under the ROC curve is 0.77.
• The sensitivity is 0.82 and specificity 0.60.
