Multiple High-Risk Features for Stage II Colon Carcinoma Portends Worse Survival Than Stage III Disease

Adjuvant chemotherapy decision-making in stage II colon adenocarcinoma associated with patients' age and high-risk factors

PURPOSE

To clarify whether the combination of age and high-risk factors (HRFs) was preferable for adjuvant chemotherapy (AC) decision-making in patients with stage II colon adenocarcinoma.

METHODS

We conducted a retrospective study analyzing eligible colon cancer patients from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2017. A nomogram was used to predict patient prognosis. Decision curve analysis (DCA) predicted model clinical benefit. Restricted cubic spline calculated the optimal cut-off value.

RESULTS

A total of 8570 patients with stage II colon adenocarcinoma were included in this study; 25.2% received AC. A nomogram predicting the prognosis of patients with stage II colon adenocarcinoma was constructed with age and HRFs, and scores were assigned to the relevant variables. DCA showed that age combined with HRFs was superior to treatment decision-making based on HRFs alone. Patients were grouped according to their total score with the cut-off value of 100. AC did not significantly improve overall survival (OS) in low-score group (hazard ratios (HRs) 1.01, 95% confidence intervals (CIs) 0.86-1.18, p = 0.918). In high-score group, AC improved 5-year OS by about 7.6% (HR 0.73, 95% CI 0.61-0.88, p = 0.001). And high-score group mainly included patients aged < 50 years with two or more HRFs and patients aged ≥ 50 years with at least one HRF.

CONCLUSION

Age and HRFs could be preferable for determining the group of stage II colon adenocarcinoma patients who would benefit from AC. Patients aged < 50 years with two or more HRFs might be a potential benefit population for AC.

Interaction analysis of high-risk pathological features on adjuvant chemotherapy survival benefit in stage II colon cancer patients: a multi-center, retrospective study

BACKGROUND

We aimed to analyze the benefit of adjuvant chemotherapy in high-risk stage II colon cancer patients and the impact of high-risk factors on the prognostic effect of adjuvant chemotherapy.

METHODS

This study is a multi-center, retrospective study, A total of 931 patients with stage II colon cancer who underwent curative surgery in 8 tertiary hospitals in China between 2016 and 2017 were enrolled in the study. Cox proportional hazard model was used to assess the risk factors of disease-free survival (DFS) and overall survival (OS) and to test the multiplicative interaction of pathological factors and adjuvant chemotherapy (ACT). The additive interaction was presented using the relative excess risk due to interaction (RERI). The Subpopulation Treatment Effect Pattern Plot (STEPP) was utilized to assess the interaction of continuous variables on the ACT effect.

RESULTS

A total of 931 stage II colon cancer patients were enrolled in this study, the median age was 63 years old (interquartile range: 54-72 years) and 565 (60.7%) patients were male. Younger patients (median age, 58 years vs 65 years; P < 0.001) and patients with the following high-risk features, such as T4 tumors (30.8% vs 7.8%; P < 0.001), grade 3 lesions (36.0% vs 22.7%; P < 0.001), lymphovascular invasion (22.1% vs 6.8%; P < 0.001) and perineural invasion (19.4% vs 13.6%; P = 0.031) were more likely to receive ACT. Patients with perineural invasion showed a worse OS and marginally worse DFS (hazardous ratio [HR] 2.166, 95% confidence interval [CI] 1.282-3.660, P = 0.004; HR 1.583, 95% CI 0.985-2.545, P = 0.058, respectively). Computing the interaction on a multiplicative and additive scale revealed that there was a significant interaction between PNI and ACT in terms of DFS (HR for multiplicative interaction 0.196, p = 0.038; RERI, -1.996; 95%CI, -3.600 to -0.392) and OS (HR for multiplicative interaction 0.112, p = 0.042; RERI, -2.842; 95%CI, -4.959 to -0.725).

CONCLUSIONS

Perineural invasion had prognostic value, and it could also influence the effect of ACT after curative surgery. However, other high-risk features showed no implication of efficacy for ACT in our study.

TRIAL REGISTRATION

This study is registered on ClinicalTrials.gov, NCT03794193 (04/01/2019).

Impact on inadequate lymph node harvest on survival in T4N0 colorectal cancer: A would-be medical center experience in Taiwan

Insufficient lymph node harvest (< 12) may lead to incorrect classification of stage I and II disease. Many studies have indicated a poor prognosis with inadequate lymph node harvest in stages I to III, but few studies have demonstrated the relationship between low lymph node harvest and T4 disease. This study aimed to identify the influence of insufficient number of lymph nodes harvested on survival in T4N0 colorectal cancer. We enrolled patients with T4N0 colorectal cancer who underwent radical resection between 2010 and 2016. A total of 155 patients were divided into 2 groups; 142 patients had ≥ 12 harvested lymph nodes, and the other 13 had < 12 lymph nodes. All patients were followed up for at least 5 years. The primary outcome was the impact of the number of lymph nodes harvested on disease-free survival and overall survival, which were investigated using Kaplan-Meier survival techniques. There were no significant differences in recurrence rate, emergent or elective surgery, laparoscopic or open surgery, or chemotherapy between the 2 groups. Kaplan-Meier analyses showed no statistical differences in 5-year disease-free survival (P = .886) and 5-year overall survival (P = .832) between the groups. There were no significant differences in disease-free survival and overall survival between patients with adequate (≥ 12) and inadequate (< 12) lymph node harvest in T4N0 colorectal cancers.