QOL Of Patients After Anterior Resection And Role Of 5-HT、TRPA1 In The Pathogenesis Of Anterior Resection Syndrome

ObjectiveAnterior resection syndrome(ARS) is the summary of a group of symptoms related to evacuation dysfunction of patients after rectal cancer operation with anal sphincter preservation. Almost 90% of the patients suffered from the ARS with a serials of symptoms including urgent,fecal frequent,frequently defecation, incompletely defecation, incontinence, and diffecult defecation. With such a disorder of bowel function background postoperatively, the quality of life(QOL) of the patients were significantly affected. Current clinical research has not yet to establish precise definitions for ARS and the pathogenesis remains unclear.Generally, the possible reasons for ARS are smaller volume of the new rectum, the transection of the enteric nervous system, etc. Recently, it has been reported that the intestinal mucosa sensory signals play an important role in the gut motility control. The prominent dysfunctional of defecation in ARS Patients implies that the abnomalities of colorectal mucosa sensory nervous function may play a role in its pathogenesis. TRPA1(transient receptor potential channel ankyrin subfamily, member 1) is the receptor molecules of the enterochromaffin(EC) cell, which can perceivesthe physical and chemical signals in the intestinal lumen and by causing Ca2++ internal flow mediated EC releasing serotonin(5-hydroxytryptamine, 5-HT) to regulate movement of the intestinal tract. To date, few of study has been reported in this area relatec to the pathogenesis of ARS. This study focused on the changes of QOL and evacuation function in patients with rectal cancer after anterior resection. Moreover, we observed the expression of 5-HT and TRPA1 immunoreactivity in the rectum before and postoperation with immunohistochemistry.Methods1. Subjects and methodsBetween November 2012 and October 2014, 200 patients in our department who diagnosed with rectal cancer and underwent anterior resection were retrospectively analysed. Among them, 105 patients who met the eligibility criteria were enrolled in this study. They were followed up by telephone, mail, and outpatient. All the patients are requested to fill out 4 forms: The Gastrointestinal quality of life questionnaire(GIQLI), the Wexner constipation score(WCS), the Wexner incontinence score(WIS) and the SF-36(The MOS Item Short From the health survey). According to the time of postoperative duration, the patients were divided into 2 groups: 0-6 months and 7-24 months. Ten patients agreed to take the mucosa biopsy during the colonoscopy examination. The expression of the 5-HT and TRPA1 protein was detected by immunohistochemistry. All the patients signed the informed consent, and this study was approved by the ethics committee of the Daping hospital.2.Research indexs1) Patients quality of life score after anterior resection of rectal carcinoma: including quality of life score, gastrointestinal tract Wexner incontinence scores, Wexner constipation score and SF-36 life quality score(include physiology, body pain, social function, general health, mental health, physical function, energy, emotion function and so on eight dimensions, also contains another health indicators: health change)2) TRPA1 receptor expression in mucosa near rectal anastomosis3) 5-HT expression in mucosa near rectal anastomosisResults1. Quality of life score in 105 cases after rectal anterior resection:1) Gastrointestinal quality of life questionnaire: Compared with the postoperatively 0-6 months group, thethe quality of life score of gastrointestinal tract in 7-24 months group was significantly improved.(P <0.05)2) Wexner constipation score: Compared with the postoperatively 0-6 month group the Wexner constipation score in the 7-24 month guoup was significantly declined.(P <0.05)3) Wexner incontinence scoreThe Wexner incontinence score in the 7-24 month guoup was significantly declined when compared with the 0-6 month group.(P <0.05)4) SF-36 health survey questionnaire: Compared with the postoperative group of 0-6 month, to the 7-24 month group showed significantly improvement in all of the items including physical function, role physical, vitality, social function, role emotional, body pain,general health, mental health and health changes(P<0.05).2.TRPA1 receptor expression in the lower rectal mucosa:Compared with the preoperative group, the TRPA1 positive expression near the anastomotic in the ARS patients was significantly reduced(P<0.05); while the expression of TRPA1 was not significantly differenct between the upper and lower of the anstomosis.(P>0.05)3. 5-HT expression in the lower rectal mucosa: Compared with the preoperative group, 5-HT positive expression near the anastomosis in the ARS patients were significantly reduced(P<0.05), and the expression between the upper and lower group of anastomosis was not significant different(P>0.05)Conclusion According to our results, overtime, the gastrointestinal life quality, constipation, fecal incontinence and health status is improved in the ARS patients significantly. The expression of rectal mucosa TRPA1 and 5-HT expression is significantly attenuated, which may play a role in the pathogenesis of ARS.