High-dose proton therapy and carbon-ion therapy for stage I nonsmall cell lung cancer.
BACKGROUND
A study was undertaken to evaluate the clinical outcome of particle therapy for stage I nonsmall cell lung cancer (NSCLC).


METHODS
From April 2003 to April 2007, 80 patients with stage I NSCLC were treated with proton therapy or carbon-ion therapy (57 with proton therapy and 23 with carbon-ion therapy) using 3 treatment protocols. In the first protocol, 80 gray equivalents (GyE) of proton therapy was given in 20 fractions, and the second proton therapy protocol used 60 GyE in 10 fractions. For carbon-ion therapy, 52.8 GyE was given in 4 fractions. After achieving promising preliminary results for the first protocol, the authors started to use the second proton therapy protocol to shorten the overall treatment time. Carbon-ion therapy was started in 2005, and thereafter, both proton and carbon-ion therapy plans were made for each patient, and the 1 that appeared superior was adopted. Patient age ranged from 48 to 89 years (median, 76 years). Thirty-seven patients were medically inoperable, and 43 refused surgery. Forty-two patients had T1 tumors, and 38 had T2 tumors.


RESULTS
The median follow-up period for living patients was 35.5 months. For all 80 patients, the 3-year overall survival, cause-specific survival, and local control rates were 75% (IA: 74%; IB: 76%), 86% (IA: 84%; IB: 88%), and 82% (IA: 87%; IB: 77%), respectively. There were no significant differences in treatment results among the 3 protocols. Grade 3 pulmonary toxicity was observed in only 1 patient.


CONCLUSIONS
Proton therapy and carbon-ion therapy are safe and effective for stage I NSCLC. Further investigation of particle therapy for stage I NSCLC is warranted.
Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan. kiki-25-h-ncu@u01.gate01.com
Hiromitsu
H
Iwata
Masao
M
Murakami
Yusuke
Y
Demizu
Daisuke
D
Miyawaki
Kazuki
K
Terashima
Yasue
Y
Niwa
Masayuki
M
Mima
Takashi
T
Akagi
Yoshio
Y
Hishikawa
Yuta
Y
Shibamoto
D000368:Aged; D000369:Aged, 80 and over; D002244:Carbon; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D007477:Ions / Q000627:therapeutic use*; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D061766:Proton Therapy; D011878:Radiotherapy / Q000009:adverse effects; D011879:Radiotherapy Dosage
D007477:Ions; D002244:Carbon