Lymph node staging in colorectal cancer: Old controversies and recent advances

Abstract

Outcome prediction based on tumor stage reflected by the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) tumor node metastasis (TNM) system is currently regarded as the strongest prognostic parameter for patients with colorectal cancer. For affected patients, the indication for adjuvant therapy is mainly guided by the presence of regional lymph node metastasis. In addition to the extent of surgical lymph node removal and the thoroughness of the pathologist in dissecting the resection specimen, several parameters that are related to the pathological work-up of the dissected nodes may affect the clinical significance of lymph node staging. These include changing definitions of lymph nodes, involved lymph nodes, and tumor deposits in different editions of the AJCC/UICC TNM system as well as the minimum number of nodes to be dissected. Methods to increase the lymph node yield in the fatty tissue include methylene blue injection and acetone compression. Outcome prediction based on the lymph node ratio, defined as the number of positive lymph nodes divided by the total number of retrieved nodes, may be superior to the absolute numbers of involved nodes. Extracapsular invasion has been identified as additional prognostic factor. Adding step sectioning and immunohistochemistry to the pathological work-up may result in higher accuracy of histological diagnosis. The clinical value of more recent technical advances, such as sentinel lymph node biopsy and molecular analysis of lymph nodes tissue still remains to be defined.

Expression of enoyl coenzyme A hydratase, short chain, 1, in colorectal cancer and its association with clinicopathological characteristics

“…Inappropriate activation or altered expression of ECHS1 is involved in several regulatory processes associated with the occurrence and progression of tumors. Elevated expression of the ECHS1 protein has been detected in several malignant tumors, including liver, colorectal, breast, bladder and prostate cancers (10). In this study, we observed a significant increase in the expression of the ECHS1 protein in CRC tissues compared to that in proximal non-cancerous colorectal tissues.…”

Adjuvant Chemotherapy for T1 Node-Positive Colon Cancers Provides Significant Survival Benefit

“…1 Following surgical treatment, the presence of lymph node metastasis has been associated with a poor prognosis, as has inadequate lymph node retrieval. 2–5 However, the use of adjuvant chemotherapy, particularly oxaliplatin, has been demonstrated to provide a significant survival benefit for patients with lymph node disease. 6–8 …”

Keratin 7 expression in lymph node metastases but not in the primary tumour correlates with distant metastases and poor prognosis in colon carcinoma

“…Colorectal carcinomas with lymph node metastases (LNM) differ in many aspects from those that do not present nodal dissemination. The former show worse prognosis, a higher recurrence rate, and shorter overall and disease-free survival [4,5]. Additionally, application of adjuvant systemic therapy also depends on the lymph node involvement [6].…”