COLORECTAL CARCINOMA- NUMBER OF EXAMINED LYMPH NODES
Abstract:
The aim was to estimate the value of sampling limph nodes (LN) located far sidelong
colorectal cancer specimens. We analyzed retrospectively surgical specimens from 345 colorectal
cancers. The fat from the mezocolon and perirectal space was divided into 2 fractions: close to (less
than 5 cm) and distant (more than 5 cm) from the tumor. Tumors were located in the cecum (n=61),
ascending colon (n=29), transverse colon (n=31), descending colon (n=27), sigmoid colon (n=108),
rectum (n=89). The median number of LN sampled was 17 in the both fractions (range 4-26), 12 (range
= 0 - 21), in the close fraction and 3 (range 0 - 28), in the distant fraction. There were 169 pNo, 104
pN1 and 72 pN2 cases. The pN staging was accurate, except 10 based on the close fraction alone: of
these, 6 were upstaged from pNo to pN1 and 4 from pN1 to pN2, were the distant fraction was
considered. In the colon, we found that LN location is more important then LN number, because
metastasis LN were present mostly in the peritumoral area. This suggests that LN should be initially
recovered from the pericolic fat, close to the tumor. If there are less than 4 positive LN and less than 12
LN examined in total, additional LN should be retrieved from the distal fraction for potential upstaging.
In the rectum, systematic sampling of close and distant LN is very important because rare cases,
metastases are detected only in the distant LN, particularly at the patients who have undergone
neoadjuvant radiotherapy.
full text article in English (.EN) |