Nasopharyngeal carcinoma in children: comparison of conventional and intensity-modulated radiotherapy.
OBJECTIVE
To evaluate the efficacy of intensity-modulated radiotherapy (IMRT) in reducing the acute toxicities associated with conventional RT (CRT) in children with nasopharyngeal carcinoma.


METHODS
A total of 36 children with nonmetastatic nasopharyngeal carcinoma, treated at the Tata Memorial Hospital between June 2003 and December 2006, were included in this study. Of the 36 patients, 28 were boys and 8 were girls, with a median age of 14 years; 4 (11%) had Stage II and 10 (28%) Stage III disease at presentation. All patients had undifferentiated carcinoma and were treated with a combination of chemotherapy and RT. Of the 36 patients, 19 underwent IMRT and 17 underwent CRT.


RESULTS
After a median follow-up of 27 months, the 2-year locoregional control, disease-free, and overall survival rate was 76.5%, 60.6%, and 71.3%, respectively. A significant reduction in acute Grade 3 toxicities of the skin (p = 0.006), mucous membrane (p = 0.033), and pharynx (p = 0.035) was noted with the use of IMRT. The median time to the development of Grade 2 toxicity was delayed with IMRT (skin, 35 vs. 25 days, p = 0.016; mucous-membrane, 39 vs. 27 days, p = 0.002; and larynx, 50 vs. 28 days, p = 0.009). The duration of RT significantly influenced disease-free survival on multivariate analysis (RT duration >52 days, hazard ratio = 5.49, 95% confidence interval, 1.14-26.45, p = 0.034). The average mean dose to the first and second planning target volume was 71.8 Gy and 62.5 Gy with IMRT compared with 66.3 Gy (p = 0.001) and 64.4 Gy (p = 0.046) with CRT, respectively.


CONCLUSIONS
The results of our study have shown that IMRT significantly reduces and delays the onset of acute toxicity, resulting in improved tolerance and treatment compliance for children with nasopharyngeal carcinoma. Also, IMRT provided superior target coverage and normal tissue sparing compared with CRT.
Laskar
Siddhartha
S
Department of Radiation Oncology, Tata Memorial Hospital, Mumbai, India.
Bahl
Gaurav
G
Muckaden
Maryann
M
Pai
Suresh K
SK
Gupta
Tejpal
T
Banavali
Shripad
S
Arora
Brijesh
B
Sharma
Dayanand
D
Kurkure
Purna A
PA
Ramadwar
Mukta
M
Viswanathan
Seethalaxhmi
S
Rangarajan
Venkatesh
V
Qureshi
Sajid
S
Deshpande
Deepak D
DD
Shrivastava
Shyam K
SK
Dinshaw
Ketayun A
KA
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D009303:Nasopharyngeal Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D009367:Neoplasm Staging; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D012189:Retrospective Studies; D015996:Survival Rate; D017741:Survivors