【Abstract】ObjectiveTo detect the spreading scope of rectal cancer to mesorectum by RT-PCR using carcinoembryonic antigen (CEA) mRNA as a marker and to investigate the excision scope of mesorectum in resection of rectal cancer. MethodsForty specimens from 40 rectal cancer patients who underwent curative operation was employed to detect the metastatic deposits scattered in the mesorectum by RT-PCR using CEA as a marker. ResultsNine of 40 (22.5%) specimens contained metastatic deposits scattered in the mesorectum. The metastasis was just within the range of 4cm mesorectum under the verge of tumor. The tumor spreading to mesorectum is correlated with Dukes stages，the infiltrated depth of bowel wall, tumor differentiation and tumor type(P＜0.05), and is not correlated with the size of tumor and the level of CEA(Pgt;0.05). ConclusionThe excision of mesorectum should be within the range of 5cm under the verge of tumor in surgical management of rectal cancer.
ObjectiveTo investigate the anatomical mark of attachment edge in mesorectal tail and the effect of its morphologic distribution in performing total mesorectal excision (TME). MethodsThe gross specimens of 220 consecutive patients with the middlelower rectal cancer were collected by a group of surgeons.Patients were divided into two groups.①Group in saving sphincter. Ⅰa group, low anterior resection (LAR): 81 patients with lesions between 5 and 6 cm from the anal verge underwent LAR ; Ⅰb group, anterior resection (AR): 68 patients with lesions between 7 and 8 cm from the anal verge underwent AR.②Group in resecting sphincter. Abdominoperineal resection (APR): 71 patients with lesions between anal verge and 5 cm from the anal verge underwent APR. Results①The circular edge of mesorectal tail is attached on rectal wall of 1 cm above anal hiatus of levators,which level parallels the lower margin of lower rectal cancer.In order to reset distal rectal wall of 2 and 3 cm,undergoing LAR must avoid injuring rectal wall when dissecting muscular vessel of rectum continue along the levators fascia to the anal hiatus.②The attachment morphology of mesorectal tail is a circular flake and not circular linear in shape. There are a little of fat tissue between posterior rectal wall and mesorectal tail,the length of its longitudinal attachment is (1.269±0.171) cm (81 cases in LAR group and 71 cases in APR gourp).Because the distal resective margin of rectum undergoing AR just locate in area of flake attachment of mesorectum, removing mesorectum around rectal wall must avoid injuring the rectal wall. Conclusion The mesorectal tail is a circular flake and attaches on rectal wall of 1.0 cm above anal hiatus of levatorani.Undergoing LAR or AR must avoid to injure rectal wall,which may result in leakage of anastomosis when removing mesorectal tissuce around distal rectal wall.
ObjectiveTo investigate the value of rectumaerated MSCT examination in diagnosis of mesorectal infiltration of rectal cancer and lymph node metastasis staging. MethodsFrom January 2010 to July 2010, the data of 68 patients with rectal cancer confirmed by pathology were analyzed in the First Affiliated Hospital of Liaoning Medical University. All the patients underwent rectumaerated MSCT preoperatively and postoperative pathology was taken as the gold standard for evaluation of the accuracy, sensitivity, specificity, positive or negative predictive values of MSCT in diagnosis of mesorectal infiltration and lymph node metastasis.ResultsIn rectum-aerated MSCT scanning, rectum and sigmoid colon was fully expanded, perirectal fat space was clear between perirectal fat space and relatively high density rectal wall and very low density enteric cavity. For mesorectal infiltration of degree Ⅰ, Ⅱ, and Ⅲ, the accuracies were 92.6%（63/68）, 91.1%(62/68), and 95.6%(65/68), respectively; sensitivities were 91.2%(31/34), 85.0%(17/20), and 92.9%(13/14), respectively; specificities were 94.1%(32/34), 93.8%(45/48), and 96.3%(52/54), respectively; positive predictive values were 93.9%(31/33), 85.0%(17/20), and 86.7%(13/15), respectively; negative predictive values were 91.4%(32/35), 93.8%(45/48), and 98.1%(52/53), respectively. For lymph node metastasis in N0, N1, and N2, the accuracies were 92.6%(63/68）,85.3%(58/68）, and 92.6%(63/68）, respectively; sensitivities were 86.2%(25/29), 90.0%(27/30), and 66.7%(6/9), respectively; specificities were 97.4%(38/39), 81.6%(31/38), and 96.6%(57/59), respectively; positive predictive values were 96.2%(25/26), 79.4%(27/34), and 75.0%(6/8), respectively; negative predictive values were 90.5%(38/42), 92.1%(35/38), and 95.0%(57/60), respectively. ConclusionsRectumaerated MSCT scaning can clearly show the depth of rectal carcinoma infiltration in the mesorectum, and N staging of mesorectal lymph node metastasis of MSCT has a higher consistency with that of pathological staging. Rectumaerated MSCT scanning is an important referenced method for clinical preoperative staging and individualized chemotherapy regimen.