A prospective evaluation of radiocolloid and immunohistochemical staining in colon carcinoma lymphatic mapping

Abstract

BACKGROUNDAlthough the utility of lymphatic mapping (LM) and sentinel lymph node (SLN) biopsy in patients with melanoma and breast carcinoma has been well documented, this same is not true for patients with colon carcinoma. The authors previously reported a high false‐negative rate for SLN biopsy in patients with colon carcinoma using isosulfan blue dye alone. The objective of the current study was to determine whether radiocolloid would increase the sensitivity of LM/SLN biopsy in patients with colon carcinoma.METHODSThe authors performed LM on 57 patients with colon carcinoma using both isosulfan blue dye and radiocolloid. The SLN(s) were identified by either their blue color or by increased radioactivity. The SLNs then underwent both routine histologic sectioning and immunohistochemical (IHC) staining for cytokeratins.RESULTSAn SLN was identified in 56 patients (98%). Radiocolloid was able to identify only 1 additional positive SLN (9%). Overall, it was found that the disease had metastasized to the lymph nodes in 22 patients, even though there was no evidence of disease in the SLN(s) in 11 of those 22 patients on routine histologic sectioning (false‐negative rate, 50%; sensitivity, 50%). In five patients, IHC of the SLN was the only indicator of metastatic disease. The inclusion of IHC‐positive SLNs in these calculations would decrease the false‐negative rate to 17% and would increase the sensitivity of SLN biopsy to 83%.CONCLUSIONSIn the current study, the addition of radiocolloid did not increase the sensitivity of detection of positive SLN(s) compared with the use of isosulfan blue dye alone. IHC of the SLN potentially may increase the sensitivity of LM and reduce the false‐negative rate. However, the long‐term prognostic significance of IHC in patients with colon carcinoma remains controversial. Cancer 2004. © 2004 American Cancer Society.

Sentinel Lymph Node Mapping in Colon Cancer: Current Status

“…9,32 For one study that used both blue dye and radiocolloid in the first few cases, but, since the same SLNs were identified with both tracers, subsequently only used blue dye in the remaining cases, the reported results were ascribed to blue dye only. 29 All of the retrieved publications concerned prospective patient series and were therefore ranked as level 3 studies (Table 1).…”

“…9,16,[18][19][20][21][22][23][24][25][26][27][28]31 Immunohistochemical staining was carried out using antibodies against cytokeratin (CK) and in one study against carcinoembryonic antigen (CEA). 23 The use of RT-PCR was only described in one study.…”

“…Additionally, microscopic error, due to a failure of the conventional histopathological analysis to detect micrometastases may contribute to understaging. 9 Another explanation may be that not all lymph nodes are harvested from the specimen and small lymph nodes with metastastic disease remain undetected. Finally, aberrant lymphatic drainage, defined as lymphatic drainage, identified outside the usual resection margins, may be problematic for adequate staging.…”

Sentinel lymph node in colorectal cancer — 5 years follow up

“…It is particularly important since there is a possibility that patients initially diagnosed as clinical stage II (having no metastases to the lymph nodes) might be up-staged to stage III (those who have metastases present in the lymph nodes) and thus be qualified for adjuvant chemotherapy. Summary of the SLNB studies in CRC is presented in the Table 4 [7,20,21,[26][27][28][29][30][31][32][33].…”

Pesquisa de linfonodo-sentinela em pacientes com adenocarcinoma de cólon

“…Patten et al 16 discordam, uma vez que em sua avaliação a sensibilidade permaneceu inalterada quando se utilizou corante associado ao fármaco radioativo.…”