Abstract 143P
Background
Colorectal carcinoma (CRC) is a third most common cancer worldwide. 1 in 24 people will develop CRC in their lifetime. Several clinical characteristics impact the survival of patients diagnosed with CRC. This study aims to describe the trend in survival rates of CRC patients from 1992 to 2020. Furthermore, we evaluated the effect of primary tumor site, size, grade, and stage on survival rates.
Methods
This was a retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER) database. The patients selected for this study were aged 20 years and older and diagnosed with CRC from 1992 to 2020. Patients with unknown tumor size, grade, metastasis, or surgery record were excluded. Patients were divided by year of diagnosis into four subgroups for comparison: 1992 – 1999, 2000 – 2006, 2007 – 2013, and 2014 – 2020. The demographic characteristics, tumor characteristics, and survival information were analyzed. The Cox proportional hazards multivariate regression model included the statistically significant survival-associated variables in the univariate analysis.
Results
The mortality rate progressively declined from the 1992–1999 group (HR: 3.89, P<0.001) to the 2000 – 2006 group (HR: 3.42, P<0.001), to the 2007 – 2013 group (HR: 2.21, P<0.001), to the 2014 – 2020 group which have the best overall survival. Patients with tumors originating in the left colon (HR: 0.89, P<0.001) have the lowest mortality rate compared to the other primary sites. As the tumor size, grade, and stage (TNM) scores increased, mortality rates increased progressively.
Conclusions
Overall survival of CRC patients continued to improve over time along the 28 years of analysis. Survival of CRC patients was inversely correlated with: Tumor size, Grade and Stage (TNM). Furthermore, patients who underwent surgery or chemotherapy had increased survival rates. Whereas patients who underwent radiation therapy had decreased survival rates. Table: 143P
| Variable | Hazard ratio (95% CI) |
| Period of diagnosis | |
| 2014–2020 | Referent |
| 2007–2013 | 2.21 ∗ |
| 2000–2006 | 3.42 ∗ |
| 1992–1999 | 3.89 ∗ |
| Primary site | |
| Right Colon | Referent |
| Left Colon | 0.89 ∗ |
| Rectum | 0.92 ∗ |
| Tumor size, cm | |
| <3.0 | Referent |
| 3.0 – 4.9 | 1.07 ∗ |
| ³5.0 | 1.10 ∗ |
| Grade | |
| I | Referent |
| II | 1.11 ∗ |
| III | 1.33 ∗ |
| IV | 1.65 ∗ |
| T value | |
| T1 | Referent |
| T2 | 1.06 ∗ |
| T3 | 1.27 ∗ |
| T4 | 1.76 ∗ |
| N value | |
| N0 | Referent |
| N1 | 1.40 ∗ |
| N2 | 1.78 ∗ |
| M value | |
| M0 | Referent |
| M1 | 3.31 ∗ |
| Surgery | |
| No/Unknown | Referent |
| Yes | 0.37 ∗ |
| Radiation | |
| No/Unknown | Referent |
| Yes | 1.06 ∗ |
| Chemotherapy | |
| No/Unknown | Referent |
| Yes | 0.64 ∗ |
∗P<0.001
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.