A comparison of tumour M2-PK with carcinoembryonic antigen and CA19-9 in patients undergoing liver resection for colorectal metastases.
BACKGROUND
The currently available tumour markers used in the management of patients with colorectal metastases are of limited value. Tumour M2-pyruvate kinase (TuM2-PK), a tumour-associated isoenzyme of pyruvate kinase, is elevated in patients with gastrointestinal cancer. This study has measured TuM2-PK levels in patients before and after resection of colorectal liver metastases (CLM).


METHODS
Fifty patients with CLM and no local residual disease had TuM2-PK levels measured before liver resection. In 20 patients, TuM2-PK levels were repeated at 2 weeks, 5 weeks and 5 months after resection. Plasma levels were analysed by enzyme-linked immunosorbent assay (ScheBo, Giessen, Germany). Carcinoembryonic antigen (CEA) and CA19-9 levels were measured at the same time periods by electrochemiluminescence immunoassay. CEA, CA19-9 and TuM2-PK levels were compared with the tumour number, volume, differentiation and stage. Cut-off values used for TuM2-PK, CEA and CA19-9 were 15 IU/ml, 10 ng/ml and 39 IU/ml, respectively.


RESULTS
TuM2-PK was elevated in 68%, CEA in 62% and CA19-9 in 40% of patients with CLM. TuM2-PK+CEA was elevated in 88% and TuM2-PK+CA19-9 in 78% of patients. A significant correlation was observed between tumour volume and CEA (r=0.34, P<0.05) and CA19-9 (r=0.49, P<0.005). TuM2-PK levels did not show a significant correlation with tumour differentiation, volume or the number of metastases. At 2 weeks after liver resection, CEA and CA19-9 levels had decreased to normal value in 73 and 67% of patients, respectively, but TuM2-PK remained elevated in all patients. At 5 weeks, TuM2-PK, CEA and CA19-9 levels decreased to normal in 64, 93 and 70% of patients, respectively, and at 5 months levels were normal in 58, 92 and 67%.


CONCLUSIONS
Plasma TuM2-PK is commonly elevated in patients with CLM. Levels do not correlate with tumour volume, number or differentiation. Levels remain elevated after liver resection, the cause of which requires further investigation.
Kumar
Yogesh
Y
University Department of Surgery, HPB and Liver Transplant Unit, Royal Free Hospital, Royal Free and University College Medical School, University College London, London, UK.
Pinedo
Inigo R
IR
Tapuria
Niteen
N
Zabron
Abigail
A
Davidson
Brian R
BR
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary* / Q000601:surgery; D008163:Luminescent Measurements / Q000379:methods; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011184:Postoperative Period; D011770:Pyruvate Kinase / Q000097:blood*
D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen; D011770:Pyruvate Kinase