[Intensity modulated radiation therapy for 49 patients with recurrent nasopharyngeal carcinoma].
OBJECTIVE
To evaluate the feasibility, toxicity and tumor control of intensity modulated radiation therapy (IMRT) for recurrent nasopharyngeal carcinoma.


METHODS
Fourty-nine patients (Karnofsky performance status (KPS) >or= 80) with local-regional recurrence in the nasopharynx were treated with full course IMRT. Three patients with cervical lymph node metastasis (N1 2 and N3 1) were further supplemented with 5 to 6 courses of chemotherapy (Cisplatin + 5-Fu) after IMRT.


RESULTS
The results of treatment plan showed that the mean dose of covering gross tumor volume (GTV) (D(95)) in the nasopharynx was 68.09 Gy and the mean volume of GTV (V(95)) receiving the 95% dose was 98.46%. The mean dose of GTV, clinical target volume CTV1 and CTV2 in the targets were 71.40 Gy, 63.63 Gy and 59.81 Gy. The median follow-up time was 9 months (range 3 to 16 months). The local-regional progression-free survival was 100% with local-regional residual disease in 3 (6.1%) cases but was complicated with nasopharyngeal mucosa necrosis in 14 (28.6%) cases after IMRT.


CONCLUSIONS
Intensity modulated radiation therapy, as a re-treatment option for recurrent nasopharyngeal carcinoma, is able to improve the tumor target coverage and spare the adjacent critical structures. As high dose IMRT can result in radio-necrosis of nasopharyngeal mucosa, the prescription dose of GTV should be suitably decreased to 60 - 65 Gy.
Lu
Tai-xiang
TX
Department of Radiation Oncology, Cancer Center, Sun Yat-Sen University, Guangzhou 510060, China.
Zhao
Chong
C
Han
Fei
F
Huang
Ying
Y
Deng
Xiao-wu
XW
Lu
Li-xia
LX
Zeng
Zhi-fan
ZF
Huang
Shao-min
SM
Lin
Cheng-guang
CG
Cui
Nian-ji
NJ
D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy*; D009367:Neoplasm Staging; D011832:Radiation Injuries / Q000473:pathology; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal / Q000379:methods*