Simultaneous measurements of KL-6 and SP-D in patients undergoing thoracic radiotherapy.
OBJECTIVE
Radiation pneumonitis (RP) is a serious complication in patients undergoing thoracic radiotherapy (TRT). Serum KL-6 and SP-D have been shown to increase in several kinds of interstitial pneumonia. To evaluate their clinical usefulness in detecting RP, we serially measured them in patients receiving TRT.


METHODS
Thirty-nine patients, who received TRT for lung cancer between July 1999 and April 2004, were prospectively studied. Serum levels of KL-6 and SP-D were measured using enzyme-linked immunosorbent assays. Patients were followed up until August 2004 or their deaths.


RESULTS
During the period, RP occurred in 19 patients. In five patients with diffuse RP extended outside the radiation field, serum KL-6 levels increased, reaching more than 1,000 U/mL. Serum KL-6 levels at 40 Gy in patients who developed RP were higher than those without it (p = 0.0363, Mann-Whitney U test). In addition, serum KL-6 levels at 40 Gy in patients who developed RP were higher than those of pretreatment (p = 0.0126, Wilcoxon signed rank test). On the other hand, there were no statistical differences between sp-d at 40 Gy and those before TRT (P = 0.1165).


CONCLUSIONS
Increased KL-6 at 40 Gy compared with those before treatment in patients undergoing TRT may be of clinical significance. KL-6 proved to be a useful indicator for estimating RP, while usefulness of SP-D was not confirmed in this study.
Matsuno
Yosuke
Y
Division of Respiratory Medicine, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan. c0430518@md.tsukuba.ac.jp
Satoh
Hiroaki
H
Ishikawa
Hiroichi
H
Kodama
Takahide
T
Ohtsuka
Morio
M
Sekizawa
Kiyohisa
K
D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D018396:Mucin-1; D009077:Mucins / Q000097:blood*; D011446:Prospective Studies; D037663:Pulmonary Surfactant-Associated Protein D / Q000097:blood*; D017564:Radiation Pneumonitis / Q000097:blood / Q000175:diagnosis*; D011878:Radiotherapy / Q000009:adverse effects; D013909:Thorax / Q000528:radiation effects*
D000951:Antigens, Neoplasm; C060192:MUC1 protein, human; D018396:Mucin-1; D009077:Mucins; D037663:Pulmonary Surfactant-Associated Protein D