Tumor marker utility and prognostic relevance of cathepsin B, cathepsin L, urokinase-type plasminogen activator, plasminogen activator inhibitor type-1, CEA and CA 19-9 in colorectal cancer

BACKGROUND

Cathepsin B and L (CATB, CATL), urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 play an important role in colorectal cancer invasion. The tumor marker utility and prognostic relevance of these proteases have not been evaluated in the same experimental setting and compared with that of CEA and CA-19-9.

METHODS

Protease, CEA and CA 19-9 serum or plasma levels were determined in 56 patients with colorectal cancer, 25 patients with ulcerative colitis, 26 patients with colorectal adenomas and 35 tumor-free control patients. Protease, CEA, CA 19-9 levels have been determined by ELISA and electrochemiluminescence immunoassay, respectively; their sensitivity, specificity, diagnostic accuracy have been calculated and correlated with clinicopathological staging.

RESULTS

The protease antigen levels were significantly higher in colorectal cancer compared with other groups. Sensitivity of PAI-1 (94%), CATB (82%), uPA (69%), CATL (41%) were higher than those of CEA or CA 19-9 (30% and 18%, respectively). PAI-1, CATB and uPA demonstrated a better accuracy than CEA or CA 19-9. A combination of PAI-1 with CATB or uPA exhibited the highest sensitivity value (98%). High CATB, PAI-1, CEA and CA 19-9 levels correlated with advanced Dukes stages. CATB (P = 0.0004), CATL (P = 0.02), PAI-1 (P = 0.01) and CA 19-9 (P = 0.004) had a significant prognostic impact. PAI-1 (P = 0.001), CATB (P = 0.04) and CA 19-9 (P = 0.02) proved as independent prognostic variables.

CONCLUSION

At the time of clinical detection proteases are more sensitive indicators for colorectal cancer than the commonly used tumor markers. Determinations of CATB, CATL and PAI-1 have a major prognostic impact in patients with colorectal cancer.

CEA and CA 19-9 measurement as a monitoring parameter in metastatic colorectal cancer (CRC) under palliative first-line chemotherapy with weekly 24-hour infusion of high-dose 5-fluorouracil (5-FU) and folinic acid (FA)

BACKGROUND

There have been contradictory reports on the benefit of CEA and CA 19-9 measurements in patients with metastatic colorectal cancer using palliative chemotherapy. The object of this study was to examine the diagnostic accuracy of monitoring of palliative chemotherapy by means of CEA and CA 19-9.

PATIENTS AND METHODS

The tumour markers CEA and CA 19-9 were subjected to serial measurement in patients with metastatic colorectal cancer (n = 90) using palliative first-line chemotherapy with weekly 24-hour infusion of high-dose 5-FU with FA and were compared with objective response according to WHO criteria. 85 patients could be evaluated. 43 patients (51%) initially had elevated CEA (> or = 10 ng/ml) and 33 patients (39%) elevated CA19-9 (> or = 50 IE/ml). In 24 patients (28%), both markers were initially increased. With CEA positive patients, 143 cycles of chemotherapy were carried out, which showed the following response in the various cycles: 21 episodes with progressions (ePD), 69 episodes with no change (eNC), 53 episodes with partial/complete remission (ePR/eCR). With CA 19-9 positive patients, 100 cycles of chemotherapy were carried out with the following results: 21 episodes with progressions (ePD), 48 episodes with eNC, and 31 episodes with ePR/eCR.

RESULTS

A CEA rise by at least 50% differentiated between ePD versus eNC/ePR/eCR with a sensitivity of 76% and specificity of 90%. With CEA decreases of at least 30% in 99% of these patient episodes (78 of 79), a tumour progression could be excluded. Patients with an initial drop in CEA after the first cycle of chemotherapy of at least 50% of the initial level had a significantly higher probability of achieving an ePR/eCR in further therapy (relative risk 2.9; P = 0.002). With an CA 19-9 increase of at least 30%, a sensitivity progression of 62% and a specifity of 90% could be calculated. A CA 19-9 decrease of at least 60% excludes a progression in 95% of the patient episodes.

CONCLUSIONS

A CEA or CA 19-9 rise is only conditionally appropriate for recording progressions. A progression however, can be excluded with falling levels with high diagnostic accuracy, in which CEA offers a greater degree of certainty than CA 19-9. With a drop in CEA 79 of 143 (= 55%) of the CT scans could be saved, in which case 78 of 79 patient episodes (99%) were correctly assessed as 'no progression'. In patients with an increased CEA and CA 19-9 the CEA determination is sufficient for the further monitoring. A confirmation of these results by multicenter trials can result in a considerable decrease of monitoring costs for palliative treatment.