Colorectal Cancer and Lymph Node Count: Is the Number Recommended for Staging Retrieved?

Abstract

Background Colorectal cancer (CRC) ranks as the third most commonly diagnosed cancer in males and the second in females. According to the TNM staging system, status of the draining lymph nodes is a key pathologic characteristic. Inadequate lymph node harvesting may result in under treatment of patients. The purpose of the present study was to evaluate the factors that influence the number of lymph nodes retrieved in colorectal cancer specimens. Methods Sixty five patients with histologically proven colorectal adenocarcinoma over a period of 18 months were included. All patients underwent surgical resection for their disease. All significant patient, tumour and treatment variables were assessed for their impact on the average total number of lymph node harvested. Further, the efficacy of the GEWF solution (glacial acetic acid, ethanol, distilled water, formaldehyde) in lymph node retrieval was also assessed. Results In this study, 43 men and 22 women with a median age of 61 years were included. The median total number of lymph nodes examined was 17. 87.6% had adequate (≥ 12) lymph nodes examined, and 12.4% had <12 nodes examined. The number of lymph nodes were found to be higher and statistically significant in under 60-year-old group (p=0.001), tumours of size > 5cm (p=0.002), tumours of the ascending colon (p=0.025) and cases operated on by super specialist surgeons (p=0.017).Factors such as gender (p=0.23),BMI (p=0.22),tumour differentiation (p=0.348) and T staging (p=0.026) had no statistically significant association with lymph node harvest. Mean LN count was significantly higher (p = 0.0001) regrossing by a senior pathologist. However a statistically significant increase in LN harvest was not seen (p=0.159) when specimens were further subjected to GEWF treatment. Conclusions This study indicates that several modifiable factors impact LN retrieval and hence gives scope for improvement. Refinement of surgical and pathological care is suggested especially in challenging cases like rectal cancer and elderly patients.