No abstract

Even though overall prostate cancer incidence rates seem to have stabilized in 2002-2010 in Navarra, trends were different by age groups: increased in men 45-74 years old and decreased in the 75+ year age-group. A decline in mortality rates was observed in both age groups since about 1995. Changes in the use of prostate specific antigen test for screening in oncoming years could affect future prostate cancer trends.

59 Background: Over the last decades the incidence of EOCRC (age 50 or less) has dramatically increased, and so has the scientific interest in this field, given that clinical and molecular characteristics in these patients are not well understood, and may be critical to identify prognostic factors. Methods: We conducted a retrospective analysis of 554 patients with metastatic colorectal cancer (mCRC), analyzing the PFS and OS of 68 (12.25%) patients with EOCRC, as well as their clinical and molecular characteristics. We used a log-rank test to compare PFS and OS, and the estimate of hazard ratio (HR) between the studied groups was calculated by means of Cox proportional hazard model. We also used the exact test of Fisher to identify significant association between categoric variants, while Mann-Whitney test was applied to identify significant differences between numeric values. Results: We performed a survival analysis: those patients with EOCRC had significantly higher median PFS in first line of treatment (16.2 vs. 11.3 months, p = 0.042) and significantly higher median OS (121.5 vs. 58.1 months, p = 0.011). Several characteristics were significantly more frequent in patients with EOCRC (n=68): BMI < 18.5 (n = 16, OR = 1.9, p = 0.046), primary tumor site at transverse colon (n = 9, OR = 2.61, p = 0.03) and ECOG 0 (n = 32, OR = 2.21, p = 0.003). Having peritoneal metastases almost reached statistical signification (n = 17, OR = 1.82, p = 0.055). Some other characteristics were less frequent: BMI 25-30 (n = 13, OR = 0.51, p = 0.046), primary tumor site at sigmoid colon (n = 14, OR = 0.49, p = 0.038) and former-smoker status (n = 7, OR = 0.44, p = 0.048). Moreover, mean values of LDH at diagnosis were significantly higher in EOCRC patients (359 U/L vs. 280 U/L, p = 0.015). EOCRC patients received a significantly higher number of lines of chemotherapy (2.94 vs. 2.38, p = 0.027) and underwent more surgeries (2,42 vs. 1.24, p < 0,001) than patients with > 50 years. Significant differences in tumor mutational status (BRAF, KRAS, NRAS, MSI, PI3K and HER2), sex, primary tumor resection or number of metastatic sites between groups were not found. Conclusions: This retrospective analysis showed that EOCRC patients had significant higher rates of PFS in first-line treatment and OS. Moreover, EOCRC patients had more frequently BMI < 18.5, primary tumor located at transverse colon and ECOG 0.

159 Background: Peritoneal metastases in patients with mCRC are commonly associated with poor outcomes. Some of these patients are candidates to undergo metastases surgery, which may result in better prognosis; however, clinical and molecular characteristics of these patients remain uncertain. Methods: We conducted a retrospective analysis of 166 patients with mCRC and peritoneal metastases in a tumor registry from 2015 to 2021, analyzing the clinical and molecular characteristics, as well as progression-free survival (PFS) and overall survival (OS) of patients who received peritoneal surgery versus those who did not. Results: From the whole population, 65 patients (39%) underwent peritoneal metastases surgery, and several characteristics were more frequent in this subgroup: ECOG 0 (n = 26, OR 2.75, p = 0,0069), age &lt;65 years (n = 43, OR 2.29, p = 0,0162), absence of hepatic metastases (n = 56, OR 3.31, p = 0,0037), single metastatic location (n = 43, OR 3.48, p = 0,0002), normal CEA levels at diagnosis (n = 33, OR 2.02, p = 0,0455) and BRAF mutation (n = 12, OR 3.32, p = 0,0345). Moreover, these patients received more lines of systemic treatment (2.8 vs 2, p = 0,006) and more metastases surgeries (1.7 vs 0.9, p = 0,000). Significant differences in tumor mutational status regardless of BRAF (KRAS, NRAS, MSI, PI3K and HER2), sex and primary tumor location between groups were not found. PFS was longer in patients receiving metastases surgery (median, 13.68 vs 7.76 months; HR for progression 0.64; 95 % confidence interval (CI) 0.46 to 0.89; p = 0,009), as well as overall survival (median NR vs 29.53; HR for death 0.39; 95 % CI, 0.25 to 0.60; p = 0,000). Conclusions: In our cohort, patients with mCRC and peritoneal carcinomatosis who underwent metastases surgery had more frequently less than 65 years, ECOG 0, absence of liver metastases, single metastatic location, normal CEA levels at diagnosis and BRAF mutation. Moreover, this subgroup showed better outcomes with a statistically significant increase in PFS and OS.

e15136 Background: A recent study has suggested that KRAS mutation could increase the risk of VTE in patients with CRC. The role of others biomarkers, such as BRAF, in this setting is unknown. The aim of this study is to analyze the incidence of cancer-associated thrombosis in a cohort of patients with CRC based on KRAS, NRAS and BRAF status. Methods: We performed a retrospective review of patients with metastatic CRC and KRAS/NRAS/BRAF status known, attended in the Medical Oncology Department of the Hospital General Universitario Gregorio Marañón (Madrid, Spain) between January 2010 and January 2018. Results: 194 patients were identified and included in the analysis. The median age was 64 years (18-86). Most were metastatic at diagnosis (58.1%). Khorana’s predictive model: low-risk 67.7%, intermediate-risk 31.0%, high-risk 2.3%. The median follow-up was 35 months (2-240). 41 patients (21.1%) experienced VTE (11 pulmonary embolism, 15 lower extremity deep-vein thrombosis, 12 visceral vein thrombosis, 2 catheter-related thrombosis, 1 unknown). Most had metastatic disease at the moment of VTE (90.2%). 40% of the events occurred at the time of diagnosis or within the first 6 months. 65% were incidental events. Khorana’s predictive model in VTE patients: low-risk 63.4%, intermediate-risk 24.5%, high-risk 7.3%. According to biomarkers, the incidence was 19.1% (13/68) in KRAS/NRAS mutated patients, 28.6% (6/21) in BRAF mutated patients and 21% (22/105) in triple-wild-type patients. 6/38 patients (15.8%) developed recurrent thrombosis. In the univariate analysis, the presence of chronic kidney disease (p = 0.022), ECOG ≥ 2 (p = 0.038) and high-risk Khorana score (p = 0.011) were significantly associated with increased risk of VTE. Metastatic disease showed a trend towards the statistical significance (p = 0.053). In the multivariate model, including this variables, age, sex and biomarkers, only ECOG ≥ 2 remained independent predictor of VTE (OR 8.73; CI 95% 1.32-57.82; p = 0.025). Conclusions: The biomarkers have not been associated with the risk of VTE. We have observed a high incidence of VTE in BRAF mutated patients that should be investigated in further studies.