Research On Lymph Nodes Metastases Distal Intramural And Mesorectal Spread Of Rectal Carcinoma Abstract

Objective: To research the rule of lymph nodes metastases distal intramural and mesorectal spread to the primary tumor of rectal carcinoma, and to provide evidence for rectal carcinoma operations.Methods: Specimens of sixty patients with rectal carcinoma who had been operated from March, 2004 to March, 2005 were collected. The specimens resected en bloc were extended to the original size and shape, handled by the fat clearing method. Lymph nodes and isolated mesenteric cancer nodes extracted using transillumination and histologically examined for metastases; then a lymph nodes and isolated mesenteric cancer nodes map was produced that included the site of the primary lesion, the vascular distribution, and the sites of extracted nodes. The distal mural at 5mm interval was cut continuously into 5mm sections and examinedmicroscopically. Analysed the significance of the fat clearing method in detection of the lymph nodes.Results: 1. The fat clearing method was more accurate than the conventional manual method for the detection of lymph nodes in rectal carcinoma. 2. The metastatic incidence of lymph nodes (nodes with metastases divided by the total of examined nodes) was correlated with age, gross type, histological type and infiltrativedepth, but not with sex, site and size of the tumor. The metastaticrate of lymph nodes (patients with metastases divided by the totalof patients) was correlated with histological type, but not withsex, age, site of the tumor, size of the tumor, gross type andinfiltrative depth. The metastatic rate of isolated mesentericcancer nodes (patients with metastases divided by the total ofpatients) was correlated with infiltrative depth, lymph nodesmetastases and Dukes stage, but not with sex, age, site of the tumor,size of the tumor, gross type and histological type. 3. Theproportion of both total number and metastases of small lymph nodeswas large and noticeable. 78% of the 2566 lymph nodes and 40.1% ofthe 202 metastatic node was 5mm in diamerer, 59. 0% of the 56 isolatedmesenteric cancer nodes was 5mm in diameter. 4. The tendency oflymph nodes metastases in rectal carcinoma was firstly to thepararectal lymph nodes group, thence to the superior hemorrhoidalartery lymph nodes group, finaly to the root of inferior mesentericarterylymph nodes group. 5. Tumor spread to the distal intramuralwas observed in 11 of 60 patients (18. 3%). The range of tumor spreadto the distal intramural was within 1. 5 cm. The tumor spread to thedistal intramural was correlated with gross type, histological typeand infiltrative depth, but not with sex, age, site of the tumor,size of the tumor, lymph nodes metastases and Dukes stage. Thespread routes to distal mesorctum mainly contained lymph nodes andisolated mesenteric cancer nodes metastases. The metastatic rateof total, lymph nodes and isolated mesenteric cancer nodes was 13. 3%...