Implications of sentinel lymph node mapping on nodal staging and prognosis in colorectal cancer

Abstract

The SN procedure results in a more accurate staging of patients with colorectal cancer. This is reflected by a better prognosis of N0 patients after SN mapping.

The effect of colonoscopic tattooing on lymph node retrieval and sentinel lymph node mapping

“…These patients at stage N1 8 will then receive adjuvant chemotherapy, leading to a better prognosis. [11][12][13] So far, sentinel node mapping has not been introduced as common practice for CRC, which is probably because of the overall disappointing sensitivity rates. 11 The aim of this retrospective study was to determine whether colonoscopic tattooing can increase the accuracy of tumor staging by analysis of the LN yield per specimen and its accuracy when used as a sentinel node procedure.…”

Qualitative and Quantitative Issues of Lymph Nodes as Prognostic Factor in Colon Cancer

“…One recent Swiss multicenter study found that the SLN procedure results in upstaging of >15% of node-negative patients [80]. Further, a Dutch study found better staging and improved survival from the SLN technique [70]. During follow-up, a lower recurrence rate was seen in N0 patients after SLN mapping compared with the conventional staging group (4 vs. 15.2%, p = 0.04).…”

“…As extended examination of all harvested lymph nodes with multiple slides appeared not to be feasible in daily practice, extensive examination of SLNs might provide highly reliable information with regard to pN status of the surgical specimen. The concept of SLN diagnosis has been investigated widely with intraoperative in vivo or ex vivo sampling [70], and with various techniques such as IHC or molecular techniques, including polymerase chain reaction (PCR) [76]. Methodological challenges and the application of both an in vivo and an ex vivo approach make comparisons difficult.…”

“…Ultrastaging, by means of IHC, may identify small lesions or clusters of cells not otherwise detected readily by the microscopic evaluation. Tumor cell deposits, defined between 0.2 and 2.0 mm, are referred to as occult metastasis (OM) or micro-metastases (pN1mi+) [70]. A number of adverse primary pathologic colon cancer characteristics, such as poor differentiation and lymphovascular invasion, correlate with the presence of OMs [71].…”

“…During follow-up, a lower recurrence rate was seen in N0 patients after SLN mapping compared with the conventional staging group (4 vs. 15.2%, p = 0.04). The SLN procedure [hazard ratio (HR) 4.1] was an independent predictor of disease recurrence [70]. In a systematic review, a total of 39 studies with 4,087 patients were included [81].…”