Clinical characteristics and outcome of pneumothorax after stereotactic body radiotherapy for lung tumors.
BACKGROUND
We retrospectively investigated the clinical characteristics and outcome of pneumothorax after stereotactic body radiotherapy (SBRT) for lung tumors.


METHODS
Between April 2003 and July 2012, 473 patients with lung tumors were treated with SBRT. We identified 12 patients (2.5 %) with pneumothorax caused by SBRT, and evaluated the clinical features of pneumothorax.


RESULTS
All of the tumors were primary lung cancers. The severity of radiation pneumonitis was grade 1 in 10 patients and grade 2 in two patients. Nine patients had emphysema. The planning target volume and pleura overlapped in 11 patients, and the tumors were attached to the pleura in 7 patients. Rib fractures were observed in three patients before or at the same time as the diagnosis of pneumothorax. The median time to onset of pneumothorax after SBRT was 18.5 months (4-84 months). The severity of pneumothorax was grade 1 in 11 patients and grade 3 in one patient.


CONCLUSIONS
Although pneumothorax was a relatively rare late adverse effect after SBRT, some patients demonstrated pneumothorax after SBRT for peripheral lung tumors. Although most pneumothorax was generally tolerable and self-limiting, careful follow-up is needed.
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Kaori
K
Asai
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. nakam@radiol.med.kyushu-u.ac.jp.
Katsumasa
K
Nakamura
Ion Beam Therapy Center, SAGA-HIMAT Foundation, Saga, Japan.
Yoshiyuki
Y
Shioyama
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Tomonari
T
Sasaki
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Yoshio
Y
Matsuo
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Saiji
S
Ohga
Faculty of Medical Sciences Department of Comprehensive Clinical Oncology, Kyushu University, Fukuoka, Japan.
Tadamasa
T
Yoshitake
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Kotaro
K
Terashima
Ion Beam Therapy Center, SAGA-HIMAT Foundation, Saga, Japan.
Makoto
M
Shinoto
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Keiji
K
Matsumoto
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Hidenari
H
Hirata
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Hiroshi
H
Honda
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011030:Pneumothorax / Q000209:etiology*; D017564:Radiation Pneumonitis / Q000209:etiology*; D016634:Radiosurgery / Q000009:adverse effects*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors
Lung cancer; Pneumothorax; Stereotactic body radiotherapy