Value of high resolution magnetic resonance imaging for preoperative evaluation of Denonvilliers fascia in patients with rectal cancer / 中华胃肠外科杂志

Objective: Total mesorectal excision (TME) is the gold standard for surgical treatment of mid-low rectal cancer, but the postoperative incidence of urination and sexual dysfunction is relatively high. Preserving the Denonvilliers fascia (DF) during TME can reduce the postoperative incidence of urination and sexual dysfunction. In this study, high resolution magnetic resonance imaging (MRI) was used to observe the imaging performance and display of DF, so as to determine the value of this technique in preoperative evaluation of the preservation of DF. Methods: A descriptive cohort study was carried out. Clinical data of patients with rectal cancer who underwent TME and received preoperative high-resolution MRI at department of Gastrointestinal Surgery, the Third Affiliated Hospital of Sun Yat-sen University from August 2015 to June 2017 were retrospectively analyzed. The characteristics of DF were examined, and the shortest distance (d) between the anterior edge of tumor and DF was measured on high-resolution MRI. The distance d was compared between patients with stage T1-T2 and those with stage T3. Receiver operating characteristic (ROC) analysis was used to determine the predictive value of d for stage T1-T2 disease. Results: Thirty-two patients were enrolled in the study, including 27 males and 5 females with mean age of (62.9±8.9) years. DF was visualized in 96.9% (31/32) of cases on the T2WI sequence. The mean distance d in patients with stage T1-T2 disease (n=23) was (6.73±2.65) mm, and in those with stage T3 disease (n=9) was (1.30±1.15) mm (t=5.893, P<0.001). A cutoff of d >3 mm yielded specificity and positive predictive value for diagnosing stage T1-T2 disease of both 100%, sensitivity of 95.7% and negative predictive value of 90%. The optimum threshold of d was >3.05 mm, and Youden index was 0.957. Conclusions: High-resolution MRI can show the DF and accurately evaluate the relationship of DF with tumor in rectal cancer patients. Analysis on d value can provide an objective basis for the safe preservation of DF.

Anatomy research on Denonvilliers fascia and its significance in nerve-preservation rectal cancer surgery / 中华胃肠外科杂志

Urinary and sexual dysfunctions due to intraoperative pelvic autonomic nerve injury have become the most common complications of rectal cancer surgery, seriously affecting postoperative quality of life. How to protect the nerve and urogenital function while ensuring radical resection for rectal cancer has become the focus of research. We previously carried out a series of systematic studies on Denonvilliers fascia, an important anatomical structure closely related to protection of pelvic autonomic nerve, and demonstrated the importance of Denonvilliers fascia in preservation of intraoperative pelvic autonomic nerve and protection of postoperative urogenital function from aspects of anatomy, physiology, tissue, operation practice and so on. Meanwhile, based on the interim results of our multicenter randomized controlled study, we confirmed that total mesorectal excision with preservation of Denonvilliers fascia (innovative TME, iTME) could effectively reduce the incidence of postoperative urinary and sexual dysfunctions in male patients with mid-low rectal cancer, without sacrificing oncologic outcome. In this article, combined with our research results, we review the literature on anatomy research progress of Denonvilliers fascia to demonstrate the significance and research prospect of Denonvilliers fascia in the pelvic autonomic nerve preservation surgery for rectal cancer.

Predictive models of adjuvant chemotherapy for patients with stage ii colorectal cancer: A retrospective study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It remains controversial whether patients with Stage II colorectal cancer would benefit from adjuvant chemotherapy after radical resection. The aim of this study was to establish two mathematical models to identify the suitable patients for adjuvant chemotherapy.</p><p><b>METHODS</b>The current study comprised of two steps. In the first step, 353 patients with Stage II colorectal cancer who underwent surgical procedures at the Third Affiliated Hospital of Sun Yat-sen University between June 2006 and December 2015 were entered and followed up for 6-120 months. Their clinical data were collected and enrolled into the database. We established two mathematical models by univariate and multivariate Cox regression analysis to identify the target patients; in the second step, 230 patients under the same standard between January 2012 and December 2016 were entered and followed up for 3-62 months to verify the two models' validation.</p><p><b>RESULTS</b>In the first step, totally 340 surgical patients with Stage II colorectal cancer were finally enrolled in this study. Statistical analysis showed that tumor differentiation (TD) (P < 0.001), lymphovascular invasion (LVI) (P < 0.001), uncertain or positive margins (UPM) (P < 0.001), and fewer lymph nodes (LNs) (<12) retrieved (P < 0.001) were correlated with the overall survival (OS) and disease free survival (DFS). We obtained two models: (1) OS risk score = 1.116 × TD + 2.202 × LVI + 3.676 × UPM + 1.438 × LN - 0.493; (2) DFS risk score = 0.789 × TD + 2.074 × LVI + 3.183 × UPM + 1.329 × LN - 0.432. According to the models and cutoff points [(0.07, 1.33) and (-0.04, 1.30), respectively], patients can be divided into three groups: low-risk, moderate-risk, and high-risk. Moreover, the high-risk group patients could benefit from adjuvant chemotherapy. In the second step, totally 221 patients were finally used to verify the models' validation. The results proved that the models were accurate and feasible (P< 0.05).</p><p><b>CONCLUSIONS</b>According to the predictive models, patients with Stage II colorectal cancer in the high-risk group are strongly recommended for adjuvant chemotherapy, thus facilitating the individualized and precise treatment.</p>

Laparoscopy-assisted combined radical resection for synchronous rectal and gastric cancer in elderly patients: report of two cases / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the safety and feasibility of laparoscopy-assisted combined radical resection for synchronous rectal and gastric cancer in elderly patients.</p><p><b>METHODS</b>Clinical data of two elderly patients undergoing laparoscopy-assisted combined radical resection for synchronous rectal and gastric cancer were analyzed retrospectively.</p><p><b>RESULTS</b>The two cases were 78 and 75 years old respectively. Both were complicated with many medical conditions. One case suffered from stage II cancer in the gastric body and stage IB rectal cancer, and the other suffered from stage IIIA gastric cancer and stage IB rectal cancer. Both cases had received laparoscopy-assisted combined radical resection for synchronous rectal and gastric cancer, with 5 cm of incision. The operative time was 260 and 255 min and the intraoperative bleeding was 60 and 80 ml respectively. No complication occurred intraoperatively. Time to resume oral intake was 4 and 5 days and length of postoperative hospital stay was 13 and 14 days respectively. No postoperative complication occurred. The patients were followed up for 13 and 12 months and no postoperative recurrence or metastasis was noticed.</p><p><b>CONCLUSION</b>Laparoscopy-assisted combined radical resection for elderly synchronous rectal and gastric cancer is safe and feasible when performed by surgeons with plentiful experience in laparoscopic technology, and associated with less injury and faster recovery.</p>

Expression and its significance of retinoic acid receptor-beta in colorectal cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the expression and its significance of retinoic acid receptor-beta (RAR-beta) in colorectal cancer.</p><p><b>METHODS</b>RAR-beta was detected by immunohistochemistry methods and carcino-embryonic antigen (CEA) was tested by chemiluminescence immunoassay methods in normal tissues, paracancerous tissues and colorectal cancer tissues of 60 patients with colorectal cancer treated from January 2006 to January 2007. Above-mentioned data, together with the clinicopathological data of these 60 patients, were analyzed to figure out the expression and its significance of RAR-beta in colorectal cancer.</p><p><b>RESULTS</b>The expression rate of RAR-beta in tumor tissues (48%) was significantly lower than those in both normal tissues (87%) and paracancerous tissues (87%) (P < 0.05). And its expression was also significant lower in patients with lymph node metastasis (32%) and patients with advanced cancer (TNM stage III and IV) (29%) than in those without lymph nodes metastasis (60%) and those with early stage cancer (stage I and II) (69%). There was no significant differences among well, mildly and poorly differentiated cancer tissues. The CEA level rose in 20 patients, and its rising rate was remarkably higher in patients with lymph node metastasis (48%) and in patients with advanced cancer (52%) than those without lymph node metastasis (23%) and in early stage(14%).</p><p><b>CONCLUSIONS</b>The expression of RAR-beta decreases significantly in cancer tissues in patients with colorectal cancer, which may be related to the carcinogenesis of colorectal cancer; and its decreasing degree is correlated negatively with the lymph node metastasis and advanced clinicopathological stage. The expression level of RAR-beta may be a new prognostic indication of patients with colorectal cancer.</p>

Celecoxib increased cellular ATRA sensitivity of human colon cancer cell lines through COX-2-independent mechanisms / 药学学报

Retinoid resistance has limited clinical activity of retinoids as differentiation-inducing and apoptosis-inducing drugs. The present study was designed to investigate whether celecoxib (selective COX-2 inhibitor) has effects on cellular retinoid sensitivity of human colon cancer cell lines and its possible mechanism. Cell viability was measured by MTT assay. Apoptosis was detected by Annexin-V/PI staining and flow cytometry assay. PGE2 production was measured by ELISA assay. Expression of RARbeta was assayed by Western blotting. The results showed that celecoxib enhanced the inhibitory effect of ATRA in both COX-2 high-expressing HT-29 and COX-2 low-expressing SW480 cell lines. Further study showed the ATRA and celecoxib combination induced greater apoptosis, and the addition of PGE2 did not affect the number of apoptotic cells induced by the combination. Moreover, NS398 (another selective COX-2 inhibitor) did not affect the inhibitory effects of ATRA on both cell lines. Western blotting showed that the expression of RARbeta in HT-29 cell lines increased in celecoxib group and combination group. And the addition of PGE2 did not affect the expression of RARbeta induced by celecoxib either. In conclusion, celecoxib increased expression of RARbeta and cellular ATRA sensitivity through COX-2-independent mechanisms, which may provide a potential strategy for combination therapy.