Comparison of Changes in Disease-Free and Overall Survival of Resectable Rectal Adenocarcinoma between 2010 and 2015

Background: Management of rectal cancer (RC) has undergone many changes in recent decades. A multidisciplinary approach to this complex disease is essential, ensuring high-quality diagnostic, treatment, and outcomes. We aimed to compare treatment results of RC in a single-centre setting between 2010 and 2015. Methods: A retrospective comparative study included patients with newly diagnosed and operated resectable RC. Patients' diagnostic and treatment data were analysed. Postoperative morbidity was measured according to the Clavien-Dindo classification. Survival data were received from the Lithuanian Cancer Registry. Continuous variables were expressed as mean and SD. Student t test and one-way ANOVA were used for parametric data and the Mann-Whitney test for non-parametric. A multivariate logistic regression analysis was used to identify independent factors for increased survival. Association between categorical variables was verified using Pearson chi(2). Results: The study included 179 patients: 80 from 2010 and 99 from 2015. Mean sample age was 67.1 +/- 10.7 years. There was no significant difference regarding age, gender, median ASA (3 in both groups), but mean hospital stay was 2 days shorter (8 vs. 10 days) in 2015 (p = 0.002). There were only 8 patients (4%) admitted to the hospital on an emergency basis. Pelvis MRI and abdominal CT were performed more often in 2015: from 37.5 to 77.8% (p < 0.001) and from 52.5 to 97% in 2015, respectively. Circumferential margin evaluation increased from 13.8 to 36.4% (p = 0.001). Neoadjuvant therapy increased from 20% in 2010 to 44.9% in 2015 (p = 0.01). The overall postoperative Clavien-Dindo complication rate was higher in 2015 (13.8 vs. 20.2%, p = 0.596), but in-hospital mortality was lower (1 vs. 0 patients). Comparison of radiological TNM and pathological TNM with one-way ANOVA showed a significant difference staging between 2010 (p = 0.002) and 2015 (p = 0.001). The 2-year overall survival (OS) increased from 76.3 to 86.9% (p = 0.046) and the median disease-free survival from 27 (range 0-35) months to 28 (range 0-35) months (72.5-83.5%, p = 0.077). Multivariate logistic regression analysis determined that availability and performance of MRI were associated with an increased OS (OR = 1.529, 95% CI 0.916-2.554, p = 0.020). Conclusions: The expanded quantity of preoperative imaging, an improved radiological staging, and compulsory multidisciplinary team board discussions have led to selective neoadjuvant treatment decision followed by surgery which can positively affect the 2-year OS rate.