Effects of proton and combined proton/photon beam radiation on pulmonary function in patients with resectable but medically inoperable non-small cell lung cancer.
OBJECTIVE
We evaluated the effects on pulmonary function of irradiating lung cancer with protons alone or protons combined with photons.


METHODS
Prospective phase I/II study.


METHODS
University medical center.


METHODS
Ten patients with stage I-II non-small cell lung cancer (NSCLC) and FEV(1) < or = 1.0 L were irradiated with protons to areas of gross disease only, using 51 cobalt gray equivalents (CGE) in 10 fractions (protocol 1). Fifteen patients with stage I-IIIA NSCLC and FEV(1) > 1.0 L received 45-Gy photon irradiation to the primary lung tumor and the mediastinum, plus a 28.8-CGE proton boost to the gross tumor volume (protocol 2).


METHODS
Pulmonary function was evaluated prior to treatment and 1 month, 3 months, and 6 to 12 months following irradiation.


RESULTS
In patients receiving protocol 1, no significant changes in pulmonary function occurred. In patients receiving protocol 2, at 6 to 12 months, the diffusion capacity of the lung for carbon monoxide had declined from 61% of predicted to 45% of predicted (p < 0.05), total lung capacity had declined from 114% of predicted to 95% of predicted (p < 0.05), and residual volume had declined from 160% of predicted to 132% of predicted (p < 0.05). Airway resistance increased from 3.8 to 5.2 cm H(2)O/L/s (p < 0.05). No statistically significant changes occurred in vital capacity, FEV(1), or PaO(2).


CONCLUSIONS
Our observations indicate that it is feasible to apply higher-than-conventional doses of radiation at a higher-than-conventional dose per fraction without excess pulmonary toxicity when conformal radiation techniques with protons are used.
Bonnet
R B
RB
Department of Pulmonary Medicine, Zentralklinik Bad Berka GmbH, Bad Berka, Germany. r.bonnet.pn@zentralklinik-bad.berka.de
Bush
D
D
Cheek
G A
GA
Slater
J D
JD
Panossian
D
D
Franke
C
C
Slater
J M
JM
D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D017785:Photons; D011522:Protons; D012129:Respiratory Function Tests
D011522:Protons