Related Research Of Primary Rectal Cancer With Magnetic Resonance Imaging

Part one Application of high-resolution magnetic resonance imaging with T2 WI and DWI in TN staging of rectal cancerpurpose: By comparing and analyzing preoperative magnetic resonance staging and postoperative pathological staging,We evaluated the diagnostic value of high resolution magnetic resonance diffusion weighted imaging in the TN staging of primary rectal cancer.Materials and Method: Using a retrospective study.First,We selected 51 patients,who’s pathological staging of rectal cancer is T1-T4,as the study object.We collected their high resolution magnetic resonance imaging(HR MRI)and diffusion weighted imaging(DWI).Second,We compared postoperative pathological staging with preoperative magnetic resonance staging,and calculate the accuracy,sensitivity,specificity,positive predictive value,negative predictive value of T-staging and N-staging separately.Third,We used the Kappa test to assess the consistency of magnetic resonance staging and pathological staging,and used spearman correlation analysis to assess the correlation between magnetic resonance staging and pathological staging.Result:1.The overall accuracy rate of T-staging measured by HR-MRI+DWI examination was 84.3%(43/51).The accuracy,sensitivity,specificity,positive predictive value,and negative predictive value obtained by comparing magnetic resonance staging and pathological staging in the T1-T4 phase are described below:T1-staging:98.0%,80.0%,100.0%,100.0%,97.9%;T2-staging:90.2%,66.7%,95.2%,75.0%,93.0%;T3-staging:86.3%,93.5%,75.0%,85.3%,88.2%;T4-staging:94.1%,66.7%,97.8%,80.0%,95.7%。2.The overall accuracy rate of N-staging measured by HR-MRI+DWI examination was 66.7%(34/51).The accuracy,sensitivity,specificity,positive predictive value,and negative predictive value obtained by comparing magnetic resonance staging and pathological staging in the N0-N2 phase are described below:N0-staging:76.5%,80.8%,72.0%,75.0%,78.3%;N1-staging:72.5%,47.1%,85.3%,61.5%,76.3%;N2-staging:84.3%,62.5%,88.4%,50.0%,92.7%.3.Consistency test between T-staging with HR-MRI+DWI and T-staging with pathological display that: Kappa=0.740,P<0.01,95% confidence interval of Kappa is 0.573-0.907,the agreement between the two is good.Both spearman correlations show positive correlation(r=0.838,P<0.01).Consistency test between N-staging with HR-MRI+DWI and N-staging with pathological display that: Kappa=0.540,P<0.01,95% confidence interval of Kappa is 0.473-0.807,the agreement between the two is generally.Both spearman correlations show positive correlation(r=0.645,P<0.01).Conclusion: High-resolution MRI can clearly show the degree of lateral invasion of rectal cancer.The combined use of DWI technology can increase the detection rate of metastatic lymph nodes.This imaging diagnosis has good consistency with the pathological gold standard.Therefore,HR-MRI + DWI has a higher diagnostic value for preoperative TN staging of rectal cancer and is worthy of clinical promotion.Part two Correlative study of ADC values and clinicopathological features,CEA and Ki-67 expression in rectal cancer.Purpose:By analyzing the correlation between the apparent diffusion coefficient(ADC)value and the clinicopathological features of rectal cancer,carcino-embryonic antigen(CEA)and Ki-67 expression levels,to explore the value of DWI non-invasive evaluation of rectal cancer invasion and prognosis.Materials and Method: We selected 49 patients with rectal cancer as subjects,and they measured ADC values before surgery.We collected their clinicopathologic data(tumor differentiation,T staging,regional lymph node metastases,intravascular tumor emboli,mesorectal fascial status)and CEA,Ki-67;We grouped each of them and then compared the differences between the ADC values for each group;We used the Pearson correlation test to analyze the correlation between ADC values and differentiation,CEA,and Ki-67 expression;according to whether the r value is positive or negative,the correlation is classified as positive and negative.Result:(1)In these 49 patients,the degree of tumor differentiation was: 11 well-differentiated,31 moderately differentiated,and 7 poorly-differentiated;T-stage: T1-2 19 cases,T3 24 cases,T4 6 cases;regional lymph nodes Metastasis: There were 37 cases of metastasis and 12 cases without metastasis;Mesorectal fascia(MRF)involvement: 18 cases involved,31 cases not involved;intravascular tumor thrombus: 13 cases with tumor thrombus,no cancer thrombus Thirty-six cases had CEA values of <10ng/m L in 37 cases and ≥10ng/m L in 12 cases.In Ki-67 positive expression,35 cases were highly expressed and 7 cases were lowly expressed.(2)The average ADC value of all rectal cancer lesions was(0.983±0.099)×10-3mm2 / s.ADC values of rectal cancers with different degree of differentiation,T stage,CEA,and Ki-67 were significantly different(p<0.01).There was no statistically significant difference in ADC values of rectal cancer in different lymph nodes,intravascular tumor thrombi,and MRF status(p>0.05).(3)The Pearson correlation test showed that the ADC value was positively correlated with the degree of tumor differentiation(r=0.651,P=0.000)and negatively correlated with the CEA level(r=-0.581,P=0.000),and negatively correlated with the expression level of Ki-67(r=-0.428,p=0.002).Conclusion:By systematically studying the characteristics of DWI and clinicopathological features,CEA,and Ki-67 in rectal cancer,we found that the ADC value was positively correlated with the degree of tumor differentiation and negatively correlated with CEA and Ki-67.As a non-invasive technique,DWI can evaluate the progression and invasion of rectal cancer preoperatively and help determine the prognosis of the tumor.