Prognostic impact of Thomsen-Friedenreich tumor antigen and disseminated tumor cells in the bone marrow of breast cancer patients.
OBJECTIVE
The Thomsen-Friedenreich antigen (TF, CD176) is a specific oncofetal carbohydrate epitope (Gal beta1-3GalNAc alpha-O-Ser/Thr) expressed on the surface of various carcinomas. It mediates endothelium adhesion and formation of metastases. As it also causes immune response, its prognostic impact is indeterminate. The presence of disseminated tumor cells in the bone marrow of breast cancer patients (DTC-BM) indicates worse prognosis. We examined the expression of TF in primary breast cancer tissue of 265 patients with known BM status at the time of first diagnosis.


METHODS
BM aspiration, cytospin preparation and immunocytochemical staining with the anti-Cytokeratin antibody A45 B/B3 was done following a standardised protocol. TF expression was examined immunohistochemically on Tissue Micro Arrays (TMA) with the anti-TF antibody A78-G/A7. Evaluation was done using the immunoreactive score (IRS).


RESULTS
Median IRS for TF expression was 2 (0-12). 68 of 265 patients (25.7%) showed DTC-BM with a median of 2/2 x 10(6) cells (1-1500). There was no correlation between TF expression and DTC-BM. After a median follow up of 60.1 months (7-119), the detection of DTC-BM showed prognostic significance for overall survival (OS, p = 0.034), whereas TF positivity (IRS > 2) indicated prolonged disease-free (p = 0.01), distant disease-free (p = 0.005), and overall survival (p = 0.005).


CONCLUSIONS
Patients with TF-positive tumors had a significantly better prognosis. Dissemination routes, TF-mediated metastasis formation, and the immunogeneity of TF might determine the prognostic impact of TF expression in different tumor entities. Further characterisation of primary tumors and DTC-BM could help to improve the biological understanding of metastases and develop targeted therapies.
Schindlbeck
Christian
C
First Department of Obstetrics & Gynecology, Ludwig Maximilians University of Munich, Maistrasse 11, D-80337, Munich, Germany. Christian.Schindlbeck@med.uni-muenchen.de
Jeschke
Udo
U
Schulze
Sandra
S
Karsten
Uwe
U
Janni
Wolfgang
W
Rack
Brigitte
B
Krajewski
Stan
S
Sommer
Harald
H
Friese
Klaus
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000032:analysis*; D001853:Bone Marrow / Q000737:chemistry / Q000473:pathology*; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D011379:Prognosis
D015295:Antigens, Tumor-Associated, Carbohydrate; C016467:Thomsen-Friedenreich antigen