Value of RT-PCR analysis of sentinel nodes in determining the pathological nodal status in colon cancer.
BACKGROUND
Pathological examination of sentinel lymph nodes (SLNs) and non-SLNs in colon cancer is frequently not performed to the same extent. We examined whether non-SLNs were truly negative in tumors with tumor-negative SLNs using reverse transcriptase-polymerase chain reaction (RT-PCR).


METHODS
RT-PCR with carcinoembryonic antigen (CEA) was performed in hematoxylin-eosin (H&E) and immunohistochemical (IHC) tumor-negative SLNs. In RT-PCR negative SLNs, we also performed RT-PCR on non-SLNs. Statistical analyses indicated the requirement for a minimum of 72 accurate comparisons of non- SLNs and SLNs, which could be fulfilled using tissues from 12 patients.


RESULTS
Negative and positive controls were performed. In nine of the 12 colon tumors, H&E and IHC-negative SLNs were also negative with CEA-RT-PCR. A total of 102 lymph nodes, including 99 non-SLNs were retrieved in these nine specimens and none of the non-SLNs were CEA RT-PCR-positive.


CONCLUSIONS
In this study, all CEA RT-PCR tumor-negative SLNs correctly reflect the tumor-negative status of the non-SLN's in primary colon tumors. The reliability of this method in colon cancer seems promising.
Kelder
Wendy
W
Departments of Surgery, 4 University Medical Center Groningen, University of Groningen, The Netherlands.
Braat
Andries
A
van den Berg
Anke
A
Platteel
Inge
I
Hollema
Harry
H
Groen
Henk
H
Plukker
John
J
D002272:Carcinoembryonic Antigen / Q000235:genetics; D003110:Colonic Neoplasms / Q000235:genetics / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*
D002272:Carcinoembryonic Antigen