Ultrastaging of sentinel lymph nodes (SLNs) vs. non-SLNs in colorectal cancer--do we need both?
BACKGROUND
The aim of this study to analyze whether ultrastaging of initially negative nonsentinel lymph nodes (non-SLNs) would increase nodal positivity in colon cancer and rectal cancer.


METHODS
After SLN mapping (SLNM), SLNs were ultrastaged by 4 hematoxylin and eosin and 1 immunohistochemistry sections. A blinded pathologist reexamined initially negative non-SLNs by 3 additional hematoxylin and eosin and 1 immunohistochemistry sections.


RESULTS
In 156 colon cancer and 44 rectal cancer patients, 2,755 nodes were identified (494 SLNs and 2,261 non-SLNs). Metastases were detected in 20.9% of SLNs and 8.6% of non-SLNs (P<.0001). After ultrastaging non-SLNs, only .58% became positive for metastases in 12 patients. Of these, 10 already had positive lymph nodes, hence no change of staging occurred. Ultrastaging upstaged only 2 of 200 patients (1%).


CONCLUSIONS
The chance of finding additional metastases by ultrastaging of all non-SLNs is extremely low (<1%) and of little benefit.
Department of Surgical Oncology, McLaren Regional Medical Center, Michigan State University, Flint, MI, USA.
David
D
Wiese
Saad
S
Sirop
Brian
B
Yestrepsky
Maher
M
Ghanem
Nader
N
Bassily
Peter
P
Ng
Weimin
W
Liu
Ernesto
E
Quiachon
Aamir
A
Ahsan
Julio
J
Badin
Sukamal
S
Saha
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000473:pathology*; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D021701:Sentinel Lymph Node Biopsy