High-dose-rate intracavitary brachytherapy boost for early T stage nasopharyngeal carcinoma{private}.
OBJECTIVE
To investigate any possible therapeutic gain from dose escalation with brachytherapy for early T stage nasopharyngeal carcinoma (NPC).


METHODS
One hundred forty-five patients with T1-2b N0-3 NPC were boosted with high-dose-rate intracavitary brachytherapy after completion of two-dimensional external radiotherapy (ERT) during the period from 1999 to 2003. To compare the efficacy of brachytherapy boost, another 142 patients with T1-2b N0-3 disease who were treated with ERT alone during 1994 to 1999 were evaluated. All patients were treated with ERT to a total dose of 66 Gy in 6.5 weeks. The brachytherapy boost group was given 10-12 Gy in 2 weekly fractions.


RESULTS
Dose escalation beyond 66 Gy with brachytherapy boost was shown to improve local control and survival. The 5-year actuarial local failure-free survival, regional failure-free survival, distant metastasis-free survival, progression-free survival, cancer-specific survival, and overall survival rates for the brachytherapy group and the control group were 95.8% and 88.3% (p = 0.020), 96% and 94.6% (p = 0.40), 95% and 83.2% (p = 0.0045), 89.2% and 74.8% (p = 0.0021), 94.5% and 83.4% (p = 0.0058), and 91.1% and 79.6% (p = 0.0062), respectively. The 5-year major-complication-free survival rate was 89.5% for the brachytherapy group and 85.6% for the control group (p = 0.23).


CONCLUSIONS
For patients who are treated with two-dimensional treatment techniques, dose escalation with brachytherapy boost improves local control and overall survival of patients with T1-T2a and possibly non-bulky T2b disease.
Leung
To-Wai
TW
Department of Clinical Oncology, Queen Mary Hospital, Hong Kong, People's Republic of China. tw_leung@hotmail.com
Wong
Victy Y W
VY
Sze
Wing-Kin
WK
Lui
Collin M M
CM
Tung
Stewart Y
SY
D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D002277:Carcinoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D016022:Case-Control Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011879:Radiotherapy Dosage; D015996:Survival Rate