Identification and initial validation of maximal tumor area as a novel prognostic factor for overall and disease-free survival in patients with resectable colon cancer: a retrospective study

BACKGROUND

The tumor area may be a potential prognostic indicator. The present study aimed to determine and validate the prognostic value of tumor area in curable colon cancer.

METHODS

This retrospective study included a training and validation cohorts of patients who underwent radical surgery for colon cancer. Independent prognostic factors for overall survival (OS) and disease-free survival (DFS) were identified using Cox proportional hazards regression models. The prognostic discrimination was evaluated using the integrated area under the receiver operating characteristic curves (iAUCs) for prognostic factors and models. The prognostic discrimination between tumor area and other individual factors was compared, along with the prognostic discrimination between the tumor-node-metastasis (TNM) staging system and other prognostic models. Two-sample Wilcoxon tests were carried out to identify significant differences between the two iAUCs. A two-sided P <0.05 was considered statistically significant.

RESULTS

A total of 3051 colon cancer patients were included in the training cohort and 872 patients in the validation cohort. Tumor area, age, differentiation, T stage, and N stage were independent prognostic factors for both OS and DFS in the training cohort. Tumor area had a better OS and DFS prognostic discrimination characteristics than T stage, maximal tumor diameter, differentiation, tumor location, and number of retrieved lymph nodes. The novel prognostic model of T stage + N stage + tumor area (iAUC for OS, 0.714, P <0.001; iAUC for DFS, 0.694, P <0.001) showed a better prognostic discrimination than the TNM staging system (T stage + N stage; iAUC for OS, 0.664; iAUC for DFS, 0.658). Similar results were observed in an independent validation cohort.

CONCLUSIONS

Tumor area was identified as an independent prognostic factor for both OS and DFS in curable colon cancer patients, and in cases with an adequate number of retrieved lymph nodes. The novel prognostic model of combining T stage, N stage, and tumor area may be an alternative to the current TNM staging system.

[Combined use of the Solitaire AB stent and Navien delivery catheter for mechanical thrombectory of acute vertebrobasilar artery occlusion]

Objective: To investigate the efficacy and safety of mechanical thrombectory with a tri-axial system of the solitaire AB stent through a Navien delivery catheter to treatment acute vertebrobasilar artery occlusion. Methods: The clinical data of 16 consecutive patients with acute ischemic stroke of vertebrobasilar artery occlusion treated with the Solitaire AB device from March 2016 to March 2018 in Department of Neurosurgery, the First Affiliated Hospital, Medical College of Shihezi University, were extracted and then retrospectively analyzed.Recanalization rate as well as complications after treatment were analysized. Also, neurological functions of the patients before and after operation 1 weeks, measured by National Institute of Health stroke scale (NIHSS) score were compared via t test and the clinical outcomes were assessed by modified Rankin score (mRS) at 90 days after operation. Results: There were 10 male and 6 female patients with a median age of 59 years (ranging from 45 to 78 years).Fourteen patients resulted in successfully recanalization, and 2 cases failed both of whose onset to sheath mean time were 8.5 hours.The NIHSS score at 7 days was 13±7, which was significantly decreased compared to the admission NIHSS score 24±4 (P=0.000).No symptomatic intracranial hemorrhage case was found after operation.At 90 days, 8 patients achieved good outcome (mRS 0 to 2), one patient died (mRS 6),two patients moderately seriously disabled (mRS 4).Three patients resulted in moderate outcome (mRS 3).In 3 cases of death,2 patients died due to failure in recanalization,another patient died of severe pulmonary infection. Conclusion: The results suggest that this technique of a tri-axial system used of the Solitaire AB stent through a Navien delivery catheter can effectively retrieve clots from the occlusive artery and improves functional outcome in patients with acute ischemic stroke of vertebrobasilar artery.