Analysis of dose-volume histogram parameters for radiation pneumonitis after definitive concurrent chemoradiotherapy for esophageal cancer.
OBJECTIVE
To evaluate dose-volume histogram (DVH) parameters as predictors of radiation pneumonitis (RP) in esophageal cancer patients treated with definitive concurrent chemoradiotherapy.


METHODS
Thirty-seven esophageal cancer patients treated with radiotherapy with concomitant chemotherapy consisting of 5-fluorouracil and cisplatin were reviewed. Radiotherapy was delivered at 2 Gy per fraction to a total of 60 Gy. For most of the patients, two weeks of interruption was scheduled after 30 Gy. The percentage of lung volume receiving more than 5-50 Gy in increments of 5 Gy (V5-V50, respectively), and the mean lung dose (MLD) were analyzed.


RESULTS
Ten (27%) patients developed RP of grade 2; 2 (5%), grade 3; 0 (0%), grade 4; and 1 (3%), grade 5. By univariate analysis, all DVH parameters (i.e., V5-V50 and MLD) were significantly associated with grade 2 RP (p < 0.01). The incidences of grade 2 RP were 13%, 33%, and 78% in patients with V20s of 24%, 25-36%, and 37%, respectively. The optimal V20 threshold to predict symptomatic RP was 30.5% according to the receiver operating characteristics curve analysis.


CONCLUSIONS
DVH parameters were predictors of symptomatic RP and should be considered in the evaluation of treatment planning for esophageal cancer.
Asakura
Hirofumi
H
Division of Radiation Oncology, Shizuoka Cancer Center Hospital, Nagaizumi, Shizuoka, Japan. h.asakura@scchr.jp
Hashimoto
Takayuki
T
Zenda
Sadamoto
S
Harada
Hideyuki
H
Hirakawa
Koichi
K
Mizumoto
Masashi
M
Furutani
Kazuhisa
K
Hironaka
Shuichi
S
Fuji
Hiroshi
H
Murayama
Shigeyuki
S
Boku
Narikazu
N
Nishimura
Tetsuo
T
D000368:Aged; D003131:Combined Modality Therapy; D004307:Dose-Response Relationship, Radiation; D004938:Esophageal Neoplasms / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017564:Radiation Pneumonitis / Q000209:etiology*; D020266:Radiotherapy, Conformal / Q000009:adverse effects*