PERINEURAL INVASION PREDICTS POOR PROGNOSIS IN STAGE I-III COLORECTAL CANCER PATIENTS

Aims Colorectal cancer (CRC) is one of the most common diagnosed cancer, and one of the major causes of cancer-related deaths Worldwide. Current treatment guidelines mostly rely on TNM classification; however recent studies suggest that additional histopathological findings could affect the disease course. Clinical significance of perineural invasion (PNI) and lymphovascular invasion (LVI) in CRC patients is still controversial. Our aim was to determine whether PNI alone or associated with LVI have an effect on 5-year overall survival (OS) of CRC patients. Methods From May 2014 till March 2015, 370 newly diagnosed CRC patients with stage I–III surgically treated at the Digestive Surgery Clinic, Clinical Center of Serbia were included. All patients had their diagnosis histologically confirmed in accordance with both TMN and Dukes classification. In addition, the patient’s demographics, histopathological details including tumor differentiation were observed and their correlation with OS was investigated. Overall survival was determined using Kaplan-Meier method as well as Cox regression model. Results LVI was identified in 124 patients (34%), whereas PNI was present in 52 patients (14%). Using Kaplan-Meier analysis, we have found that both LVI and PNI were associated with lower survival rates (P < 0.01). Moreover when Cox multiple regression model was used, LVI, PNI, older age, higher BMI, poor differentiation, as wel as depth of the tumor and right side localisation were significant factors predicting poor prognosis OS (HR = 2.73, 95%CI 1.54–4.83,P < 0.01). Conclusions PNI alone, as well as LVI were associated with poor prognosis in CRC patients, hence more aggressive therapy should be reserved for these patients after curative resection.