Background: Colorectal cancer (CRC) is one of the most common malignancies worldwide. It is the third most common malignancy worldwide after lung cancer and breast cancer respectively. CRC is the second leading cause of death after lung cancer. CRC is also widespread in Egypt. According to Egypt National Cancer Registry, Colorectal Cancer ranks the seventh either in males or females.
Aim of the Work: identifying the prognostic significance of metastatic LNR (mLNR) by analyzing survival rates; disease-free survival (DFS) and overall survival (OS) of adult patients diagnosed with non-metastatic CRC who were treated at Clinical Oncology Department Ain Shams University hospitals & Damanhur Oncology Center in the period from January 2015 to end of December 2020.
Patient and Methods: This is a retrospective cohort study conducted on 116 non metastatic CRC adult patients who were treated at Ain Shams clinical oncology department and Damanhur oncology center in the period from January 2015 to end of December 2020. Depending on ratio of positive LNs to the total number of LNs resected, Patients were categorized into five groups; LNR0 in which patients have no metastatic lymph nodes, LNR1; patients have LNR between 0.1 and 0.17, LNR2, patients have LNR between 0.18 and 0.41, LNR3, patients have LNR between 0.42 and 0.69 and the last group, LNR4in which patients have LNR >0.7. Patients' personal history and clinical data were collected and analyzed together with results of laboratory and radiological investigations in addition to follow-up data for estimating survival rates (OS and DFS) of the five groups' patients.
Results: According to staging in the five groups, about 86% (n=26) of patients in LNR0 group were classified as stage 2, 100% of patients in LNR1, LNR2, LNR3, LNR4 group were classified as stage 3. In terms of survival rates; the mean overall survival was 62.25 months while the mean DFS was 51.14 months with median of 50.3 months. OS and DFS were significantly differed between the studied groups as regard OS that was 96.7%, 88.9%, 82.6%,70%, 50% in LNR0, LNR1, LNR2, LNR3, LNR4 respectively and disease-free survival was 93.3%, 85.2%, 60.9%, 45%, 28.8% respectively.
Conclusion: We concluded that, in the present series of non-metastatic CRC patients, a highly significant association was revealed between mLNR and prognosis of non-metastatic CRC as regard OS and DFS.