Preservation of the continence function after intersphincteric resection using a prolapsing technique in the patients with low rectal cancer and its clinical prognosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The technique of intersphincteric resection of tumors combined with coloanal anastomosis has been used to avoid permanent colostomy for patients with a rectal cancer located < 5 cm from the anal verge. This study aimed at assessing the preservation of continence function of the residual rectum and the clinical prognosis of patients with lower rectal cancer after intersphincteric resection using a prolapsing technique.</p><p><b>METHODS</b>This study included patients with the following inclusion criteria: (1) pathological evidence of rectal cancer and the tumors within distal margins located 5 cm or less from the anus by preoperative endoscopic examination; (2) no evidence by MRI of infiltration of either the external sphincter, puborectalis or the levator muscle; (3) the patients are eligible for intersphincteric resection and lower coloanal anastomosis with a preoperative biopsy showing the tumors with well-to-moderate differentiation. From January 2000 to June 2004, 23 patients with low rectal cancer were included in this study. We used the standard abdominoperineal approach to perform radical resection of tumors with excision of the mesorectum and total or part of the internal sphincters. The patients were followed for assessment of the function of the residual rectum and of cancer recurrence after the operations.</p><p><b>RESULTS</b>The median tumor distance from the anal margin was 4.5 (range 3.5 - 5.0) cm and the mean distal surgical margin 1.6 (range 1.0 - 2.0) cm. Cancer was classified into Stage I (30.4%), Stage II (47.8%), and Stage III (21.7%) according to the TNM classification. Two patients developed anastomotic fistula after the surgical resection and 2 patients (8.7%) developed later stages of anastomotic stricture at the site of coloanal anastomosis. The median follow-up period was 31.5 months (range 12 - 54) and 2 patients (8.7%) developed local recurrence. Three deaths were associated with distal organ metastasis. Twenty patients (87.0%) have maintained competence to control solid or liquid stool and the capacity of flatus continence after the surgery. Among these patients, 2 patients were able to control solid stool and occasionally lose continence of liquid stool. And only 1 patient (4.4%) has retained partial rectum function with good continence of solid stool but not liquid after the operations. Average times of defecation per day of 3, 6, 12, 24 and 36 months after the surgery were 13.1, 4.7, 3.1, 2.9, and 3.2 times/day. Anal manometer measurements showed a decrease of pressure during the resting time after intersphincteric resection and this change remained during the period of follow-up. The maximum squeeze pressure was improved after an initial decrease after the surgery.</p><p><b>CONCLUSIONS</b>More residual rectum function after the surgery may be preserved by intersphincteric resection of low rectum cancer. At the same time this technique is safe with few postoperative complication and low tumor recurrence after the surgery.</p>

Paclitaxel-doxorubicin sequence is more effective in breast cancer cells with heat shock protein 27 overexpression / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cancer cells with overexpression of heat shock protein 27 (HSP27) are resistant to chemotherapeutic drug doxorubicin (Dox). Paclitaxel (Pacl) was reported to suppress HSP27 expression in ovarian and uterine cancer cells. The purposes of this study were to investigate whether Pacl inhibits the expression of HSP27 in breast cancer cells, whether Pacl can sensitize breast cancer cells with HSP27 overexpression to Dox, and to define a more effective schedule for the combination of Dox with Pacl.</p><p><b>METHODS</b>The HSP27 high-expressing human breast cancer cell lines, MCF-7 and MDA-MB-435, and the HSP27 low-expressing cell line, MDA-MB-231, were used in this study. The level of HSP27, topoisomerase (Topo) IIalpha and beta expression were assessed by Western blotting. The cytotoxic activities of Dox, Pacl and combination of these two drugs were evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay and flow cytometric assays.</p><p><b>RESULTS</b>Pacl (0.1 micromol/L) inhibited HSP27 expression by approximately 2-fold in MCF-7 and MDA-MB-435 cells, while up-regulating the level of topo IIalpha and beta. In contrast, expression of HSP27 in MDA-MB-231 did not change significantly following Pacl treatment. There were synergistic effects in both treatment sequences (Pacl-Dox and Dox-Pacl) when Pacl was combined with Dox. Compared with those treated with the Dox-Pacl sequence, the Pacl-Dox sequence had a stronger effect in cancer cells with HSP27 overexpression, as MCF-7 and MDA-MB-435 treated with the Pacl-Dox sequence had lower viabilities and a higher apoptotic rate.</p><p><b>CONCLUSIONS</b>Paclitaxel significantly decreases the level of HSP27 in breast cancer cells overexpressing HSP27. In combination therapies, the Pacl-Dox sequence is more effective in clearing breast cancer cells with high HSP27 expression compared with the Dox-Pacl sequence.</p>

Regional blood perfusion and biological characteristic of breast cancer / 中国普通外科杂志

Objective To evaluate the correlation between regional blood perfusion and biological features of breast cancer. Methods Spiral CT technique was applied to quantitatively detect the central and marginal blood perfusion, including blood flow ( BF ) , blood volume ( BV) and permeability of surface (PS). Results The central and marginal blood perfusion of breast cancer were significantly higher than that of normal breast tissues. The marginal blood perfusion was higher than central blood perfusion. The regional blood perfusion of breast cancer varied with tumor size, clinical stage and histological grading. Conclusion The regional blood perfusion correlates with biological markers in breast cancer and can be used to evaluate the biological characteristics as a noninvasive marker before neoadjuvant chemotherapy.