Purpose: The study contained herein was undertaken to investigate fecal calprotectin excretion in a series of patients with colorectal carcinoma and to determine whether the excretion was influenced by localization or stage of the tumor. Furthermore, the effect of surgical treatment on the concentrations was studied. Fecal calprotectin was also compared with plasma concentrations of calprotectin, carcinoembryonic antigen, and C-reactive protein.
Methods: Fecal calprotectin was measured in 119 consecutive patients admitted for treatment of colorectal carcinoma. In 116 (97.5 percent) patients, resectional surgery was performed. Plasma calprotectin was measured in 90 (76 percent) patients, carcinoembryonic antigen in 88 (74 percent) patients, and C-reactive protein in 82 (69 percent) patients.
Results: Median fecal calprotectin concentration in the 119 patients was 50 (range, 2-950) mg/l, which was significantly (P < 0.0001) higher than in 125 control patients (median, 5.2 mg/l). In 23 patients studied also after resection, the excretion fell greatly. There were no significant differences in fecal calprotectin concentration among patients with different tumor stages. Elevated plasma calprotectin concentrations were found in 67 of 90 (73.3 percent) patients with colorectal carcinoma, compared with elevated fecal calprotectin in 111 of 119 (93.3 percent) patients, and there was no significant correlation between plasma and fecal calprotectin concentrations. Plasma calprotectin concentrations were significantly lower in patients with T1 or T2 tumors than in those with more advanced stages (P = 0.0025).
Conclusion: Measurement of fecal calprotectin may become a diagnostic tool in detecting colorectal carcinoma. The specificity in relation to colorectal carcinoma has not, however, been completely investigated. Both neoplastic and inflammatory conditions may be associated with elevated values; therefore, it is unlikely that calprotectin can predict specific colonic disorders.