Effect of Lymphatic Mapping on the New Tumor-Node-Metastasis Classification for Colorectal Cancer

Abstract

Conventional examination of lymph nodes for CRC is inadequate for the detection of MM and ITC as described in the new TNM classification. Thus, LM and focused SN analysis should be considered to fully stage CRC.

Acometimento metastático linfonodal no câncer colorretal

“…Estes pacientes poderiam se benefi ciar de ressecções cirúrgicas mais amplas (31) . O estudo mostrou que o grupo de LN mais impactante no estádio (pN) é o de LN peritumorais, resultado justifi cado pelo maior número de LN no grupo, pela característica da drenagem linfática (22) (mais próxima do tumor e intensa) e pela provável presença do LN sentinela entre os LN peritumorais (6) , sendo a drenagem linfática aberrante incomum no CCR (4,0%) (10) . Estudos objetivando a otimização do pN mostraram que a análise detalhada do LN sentinela implica em estádio mais acurado.…”

“…A avaliação do perfi l qualitativo dos LN tem assumido importância crescente. Nesse contexto, o estudo do LN sentinela (6,10) (LN que recebe drenagem linfática diretamente da lesão primária), do tamanho dos LN (10) e das metástases nos LN (26,32) , da localização dos LN em relação à topografi a da lesão (8) , à proximidade do tumor (11) e de tronco vascular específi co (16) têm sido avaliados em relação ao prognóstico. O uso da imunoistoquímica mostrou-se método efi ciente na detecção de micrometástases (metástases menores que 2 mm) (6) , com impacto no estádio e no prognóstico dos pacientes (6,7,12) .…”

Intraoperative sentinel lymph node mapping in patients with colon cancer: Study of 38 cases

“…Tsioulias et al (34), in their study in which they applied dye injections through colonoscopy to 14 patients who had undergone laparoscopic colectomy, obtained a false-negative result in 1 patient. In the literature, it has been reported that in studies where false-negative rates were relatively high in SLN mapping of colorectal cancers, the reasons were mostly technical errors, lack of experience in SLN mapping, and patients in advanced stages such as stage III-IV (2,9,(13)(14)(15)(16)(17)(18)(19)22,25,(27)(28)(29)(30)(31)(32)(33)(34)(35). While falsenegative rates were reported as 0-75% in the compilation prepared by Cahill et al (26), it is observed that in only 10 of the studies, the false-negative rate is over 30%.…”

“…In studies that have used SLN mapping, aberrant lymphatic drainage was reported in 0-10% of the patients (2,9,(13)(14)(15)(16)(17)(18)(19)22,25,(27)(28)(29)(30)(31)(32)(33)(34)(35)(36). In our present study, we had no patients with aberrant lymphatic drainage.…”

“…The optimal number of lymph nodes necessary for a definitive staging based on lymph nodes must be at least 12 to 16 (21)(22)(23) on 50 consecutive patients with colorectal cancer, they determined the recognition rate of lymph nodes to be 70% and the sensitivity to be 45%. Fifteen patients whose SLN dyeing was negative were further subjected to immunohistochemical dyeing, and metastasis was discovered in 2 of the patients.…”