Risk Prediction And MRI Imaging Evaluation Of Cervical Cancer-related Radiation Proctiti

Part Ⅰ: Risk prediction of patients with severe radiation proctitis associated with cervical cancerObjectives: To investigate the clinical and imaging risk factors of severe radiation proctitis after radical radiotherapy for cervical cancer.Methods: The patients with stage IIb-IV cervical cancer and radiation proctitis after radical radiotherapy who were admitted to Yunnan Cancer Hospital from October2015 to December 2020 were retrospectively analyzed.After the inclusion and exclusion criteria were set,they were divided into severe radiation proctitis group and non-severe radiation proctitis group(patients with mild-moderate radiation proctitis)according to the colonoscopy and radiation injury grading standard(RTOG/EORTC).The clinical and imaging data of patients before radiotherapy were collected,and the risk factors of severe radiation proctitis in patients with cervical cancer after treatment were screened by univariate analysis and multivariate logistic regression analysis.Results: Finally,128 patients with cervical cancer were enrolled,including 32 patients with severe radiation proctitis and 96 patients with non-severe radiation proctitis.Univariate analysis showed that age,tumor stage,history of pelvic surgery,time after treatment,total number of chemotherapy,external irradiation technique and presence or absence of metastatic lymph nodes were statistically significant between the two groups(P < 0.05).Multivariate logistic regression analysis showed that age,stage,synchronous chemotherapy,serum albumin level before radiotherapy,previous pelvic surgery history and lymph node metastasis were independent risk factors for cervical cancer-related severe proctitis(P < 0.05).Conclusions: Among patients with cervical cancer,the later the tumor stage before treatment,the lower the serum albumin level,the pelvic lymph node metastasis and the previous history of pelvic surgery,the higher the risk of severe radiation proctitis after treatment.Part Ⅱ: MRI evaluation of radiation enteritis in patients with cervical cancerObjectives:To analyze the MRI manifestations of radiation proctitis in patients receiving radical radiotherapy,and to explore the value of MRI in evaluating radiation proctitis associated with cervical cancer.Methods: The patients admitted to Yunnan Cancer Hospital from October 2015 to December 2020 who received radical radiotherapy for stage IIb to IV cervical cancer were divided into mild,moderate and severe radiation proctitis according to the results of colonoscopy.The pelvic MRI images of patients in the same period were reviewed,and 11 indexes were evaluated,such as the signal change of anterior rectal wall,the thickness of rectal wall,the way of strengthening intestinal wall and the fat space around intestine,and the correlation between these MRI signs and the severity of radiation proctitis was analyzed.Using the results of colonoscopy as the gold standard,the diagnostic accuracy of MRI imaging indexes in cervical cancer-related radiation proctitis was evaluated.Results: According to the admission criteria,102 patients with cervical cancer were finally included,suffering from radiation proctitis-68 cases were mild,25 cases were moderate and 9 cases were severe.Compared with mild enteritis,patients with moderate to severe radiation proctitis are more likely to have abnormal MRI images,including: uneven thickening of rectal wall,decreased T2 WI signal of anterior mucosa and submucosa,strip-shaped low signal band in submucosa,blurred wall,low signal shadow of periintestinal fat on T2 WI,and obvious enhancement without layering(P < 0.05);However,there was no significant difference in the thickness of the anterior rectal wall and the presence or absence of pelvic effusion between the two groups(P > 0.05).MRI and colonoscopy are highly consistent in distinguishing different degrees of radiation rectum(Kappa value is 0.7,P value is 0.000).Conclusion(s): Pelvic MRI has high diagnostic accuracy for different degrees of radiation proctitis in patients with cervical cancer receiving radical radiotherapy,and it is expected to become a routine follow-up means for such patients.