AIM: Local recurrence after curative surgical resection for rectal cancer remains a major problem. Several studies have shown that incomplete removal of cancer deposits in the distal mesorectum contributes a great sha...AIM: Local recurrence after curative surgical resection for rectal cancer remains a major problem. Several studies have shown that incomplete removal of cancer deposits in the distal mesorectum contributes a great share to this dismal result. Clinicopathologic examination of distal mesorectum in lower rectal cancer was performed in the present study to assess the incidence and extent of distal mesorectal spread and to determine an optimal distal resection margin in sphincter-saving procedure.METHODS: We prospectively examined sepecimens from 45 patients with lower rectal cancer who underwent curative surgery. Large-mount sections were performed to microscopically observe the distal mesorectal spread and to measure the extent of distal spread. Tissue shrinkage ratio was also considered. Patients with involvement in the distal mesorectum were compared with those without involvement with regard to clinicopathologic features.RESULTS: Mesorectal cancer spread was observed in 21patients (46.7%), 8 of them (17.8%) had distal mesorectal spread. Overall, distal intramural and/or mesorectal spreads were observed in 10 patients (22.2%) and the maximum extent of distal spread in situ was 12 mm and 36 mm respectively. Eight patients with distal mesorectal spread showed a significantly higher rate of lymph node metastasis compared with the other 37 patients without distal mesorectal spread (P = 0.043).CONCLUSION: Distal mesorectal spread invariably occurs in advanced rectal cancer and has a significant relationship with lymph node metastasis. Distal resection margin of 1.5 cm for the rectal wall and 4 cm for the distal mesorectum is proper to those patients who are arranged to receive operation with a curative sphincter-saving procedure for lower rectal cancer.展开更多
AIM: To study the distribution of positive lymph nodes within mesorectum and to investigate the possible micrometastasis in negative lymph nodes. METHODS: Large slice technique combined with tissue microarray was used...AIM: To study the distribution of positive lymph nodes within mesorectum and to investigate the possible micrometastasis in negative lymph nodes. METHODS: Large slice technique combined with tissue microarray was used in the pathologic study of 31 specimens.RESULTS: A total of 992 lymph nodes were harvested and cancer metastasis was found in 148 lymph nodes. Some positive lymph nodes were located in the outer layer of mesorectum and more at the same site of mesorectum as the primary tumor. Circumferential margin lymph node metastasis was observed in nine cases. No significant difference in occurrence of micrometastasis was observed in different stage tumors. CONCLUSION: Positive lymph nodes are distributed in mesorectum and micrometastasis can be found in negative lymph nodes.展开更多
基金Supported by the Key Project of National Outstanding Youth Foundation of China, No. 39925032
文摘AIM: Local recurrence after curative surgical resection for rectal cancer remains a major problem. Several studies have shown that incomplete removal of cancer deposits in the distal mesorectum contributes a great share to this dismal result. Clinicopathologic examination of distal mesorectum in lower rectal cancer was performed in the present study to assess the incidence and extent of distal mesorectal spread and to determine an optimal distal resection margin in sphincter-saving procedure.METHODS: We prospectively examined sepecimens from 45 patients with lower rectal cancer who underwent curative surgery. Large-mount sections were performed to microscopically observe the distal mesorectal spread and to measure the extent of distal spread. Tissue shrinkage ratio was also considered. Patients with involvement in the distal mesorectum were compared with those without involvement with regard to clinicopathologic features.RESULTS: Mesorectal cancer spread was observed in 21patients (46.7%), 8 of them (17.8%) had distal mesorectal spread. Overall, distal intramural and/or mesorectal spreads were observed in 10 patients (22.2%) and the maximum extent of distal spread in situ was 12 mm and 36 mm respectively. Eight patients with distal mesorectal spread showed a significantly higher rate of lymph node metastasis compared with the other 37 patients without distal mesorectal spread (P = 0.043).CONCLUSION: Distal mesorectal spread invariably occurs in advanced rectal cancer and has a significant relationship with lymph node metastasis. Distal resection margin of 1.5 cm for the rectal wall and 4 cm for the distal mesorectum is proper to those patients who are arranged to receive operation with a curative sphincter-saving procedure for lower rectal cancer.
基金Supported by the Grants From the Key Project of National Outstanding Youth Foundation of China,No.39925032
文摘AIM: To study the distribution of positive lymph nodes within mesorectum and to investigate the possible micrometastasis in negative lymph nodes. METHODS: Large slice technique combined with tissue microarray was used in the pathologic study of 31 specimens.RESULTS: A total of 992 lymph nodes were harvested and cancer metastasis was found in 148 lymph nodes. Some positive lymph nodes were located in the outer layer of mesorectum and more at the same site of mesorectum as the primary tumor. Circumferential margin lymph node metastasis was observed in nine cases. No significant difference in occurrence of micrometastasis was observed in different stage tumors. CONCLUSION: Positive lymph nodes are distributed in mesorectum and micrometastasis can be found in negative lymph nodes.
