Serum Clara cell protein levels in lung cancer patients: an assessment of preoperative values and postoperative changes.

Serum levels of protein 1 (P1), a Clara cell protein known to have an antiinflammatory effect, were studied in 33 patients with lung cancer before surgery, and 3, 7, 14, 21 days, and 2 months after surgery. The preoperative P1 values of the lung cancer patients were compared with those of 66 healthy controls matched by sex and age. The postoperative changes in P1 which occurred in the lung cancer patients were compared with those in 16 patients who underwent laparotomy for gastric or colon cancer. There was no significant difference in the P1 values between the lung cancer patients and the healthy controls; however, the postoperative P1 values showed a significant decrease 3, 7, (P < 0.001), and 14 days (P < 0.05) postoperatively, recovering to normal within 2 months after surgery. One patient who died of postoperative pneumonia showed decreasing serum P1 levels until death. None of the laparotomy patients showed any decrease in P1 serum levels. Thus, we conclude that: (a) serum P1 levels do not differ between lung cancer patients and healthy individuals; (b) serum P1 levels significantly decrease in the early postoperative period, but recover within 2 months after lung resection; and (c) the postoperative changes that occur in serum P1 levels could provide important information about recovery from intraoperative lung damage.