The significance of CEA, CA19-9 and CA72-4 in the detection of colorectal carcinoma recurrence

The significance of CEA, CA19-9 and CA72-4 was evaluated the for early dete ction of disease recurrence, on the basis of retrospective evaluation of ro utine data in patients with colorectal carcinoma. They also considered the dependence of the results of these data analyses on the definition of group s of patients, both with no evidence of disease (NED) and with recurrence o f disease (RD). Patients and Methods: From January 1994 to March 1999 serum levels of CEA, CA19-9 and CA72-4 were determined in the follow-up of 517 p atients with colorectal cancer and compared with the retrospectively confir med clinical status of the patients. Results: CEA and CA19-9 showed compara ble sensitivities in the detection of locoregional recurrence of colorectal carcinoma, whilst the sensitivity of CA72-4 was considerably lower: CEA is an optimal marker for detecting distant metastases, in particular liver me tastases, since its sensitivity considerably exceeds the sensitivities of t he other two monitored markers. Conclusion: Using routine data required det ailed analysis and clear definitions of groups of patients with NED and RD. The following conclusions for the evaluation of data were drawn from this analysis: a) Tumor marker cut-off values and sensitivities related to 95% s pecificity of remission values depended strongly on the given definition of the groups of patients with NED and RD. b) The patient group with NED is b est characterized as the group of patients who never developed progression and where all the values which were assessed within a period shorter than s ix months from the end of therapy and follow-up, or less than six months be fore progression, death, or before the last marker assessment in the patien t, were excluded. c) For the optimal characterisation of the group of patie nts with RD it is recommended only to consider values obtained during the f irst progression, after the period of complete post-operative or post-thera peutic remission. d) These conclusions refer not only to routine data, wher e this correction represents a condition for reliable evaluation, but also to any research done, since they ensure complete homogeneity of the group a nd mutual comparability of the results.