Risk factors for surgical site infection and association of surgical site infection with survival of lower rectal cancer patients without clinical lateral pelvic lymph node metastasis (clinical Stage II/III): Analysis of data from JCOG0212.

This study aimed to examine the risk factors for surgical site infection (SSI) and the association of that with recurrence in JCOG0212. The results for secondary endpoints showed that compared with the mesorectal excision (ME) alone group, ME with lateral lymph node dissection (LLND) group showed significantly longer operative time and significantly higher blood loss. These results suggested that LLND was a risk factor for SSI. All 701 patients registered in JCOG0212 were analyzed in this study. Wound infection was defined as incisional/deep SSI, and pelvic abscess and anastomotic leakage were defined as organ/space SSI. The risk factors for the incidence of SSI and the effect of SSI on relapse-free survival (RFS) were investigated. Multivariable odds ratio of Grade 2 or higher all SSI was 0.58 [95% Confidence interval: 0.36-0.93] for female (vs. male) and that of Grade 2 or higher incisional/deep SSI was 2.24 [1.03-4.86] for blood infusion. For RFS, patients with Grade 3 or higher all SSI showed poor prognosis (multivariable hazard ratio: 1.66 [1.03-2.68]). LLND is not significant factor for the incidence of all SSI. Male sex might be a risk factor of Grade 2 or higher SSI, and blood transfusion is a possible risk factor of Grade 2 or higher incisional/deep SSI. Grade 3 or higher all SSI might be a significant worse prognostic factor for lower rectal cancer.

Predictive factors of pathological lateral pelvic lymph node metastasis in patients without clinical lateral pelvic lymph node metastasis (clinical stage II/III): The analysis of data from the clinical trial (JCOG0212).

BACKGROUND: Mesorectal excision (ME) is the standard surgical procedure for lower rectal cancer. However, in Japan, total or tumor-specific ME with lateral pelvic lymph node dissection (LLND) is the standard surgical procedure for patients with clinical stages II or III lower rectal cancer, because lateral pelvic lymph node metastasis occasionally occurs in these patients. The aim of study was to elucidate the predictive factors of pathological lateral pelvic lymph node metastasis in patients without clinical lateral pelvic lymph node metastasis. METHODS: Data form the clinical trial (JCOG0212) was analyzed. The JCOG0212 was a randomized controlled trial to confirm the non-inferiority of mesorectal excision alone to mesorectal excision with lateral lymph node dissection for clinical stage II/III patients who don't have clinical lateral pelvic lymph node metastasis in terms of relapse free survival. This study was conducted at a multitude of institution33 major hospitals in Japan. Among the 351 patients who underwent lateral lymph node dissection in the JCOG0212 study, 328 patients were included in this study. Associations between pathological lateral pelvic lymph node metastasis and preoperative and postoperative factors were investigated. The preoperative factors were age, sex, clinical stage, tumor location, distance from anal verge, tumor size, and short-axis diameter of lateral pelvic lymph node on computed tomography and the postoperative factors were pathological T, pathological N, and histological grade. RESULTS: Among the 328 patients, 24 (7.3%) had pathological lateral pelvic lymph node metastasis. In multivariable analysis of the preoperative factors, patient age (p = 0.067), tumor location (p = 0.025), and short-axis diameter of lateral pelvic lymph node (p = 0.002) were significantly associated with pathological lateral pelvic lymph node metastasis. CONCLUSIONS: Patient age, tumor location, and short-axis diameter of lateral pelvic lymph node were predictive factors of pathological lateral pelvic lymph node metastasis.

Urinary dysfunction after rectal cancer surgery: Results from a randomized trial comparing mesorectal excision with and without lateral lymph node dissection for clinical stage II or III lower rectal cancer (Japan Clinical Oncology Group Study, JCOG0212).

BACKGROUND: Postoperative urinary dysfunction is a major complication of rectal cancer surgery. A randomized controlled trial (JCOG0212) concluded that the noninferiority of mesorectal excision alone to mesorectal excision with lateral lymph node dissection was not confirmed in terms of relapse-free survival. METHODS: Eligibility criteria included histologically proven clinical stage II/III rectal cancer, a main lesion located in the rectum with the lower margin below the peritoneal reflection, and the absence of lateral lymph node enlargement. After confirming R0 resection by mesorectal excision, patients were randomized intraoperatively. The residual urine volume was measured three times. Urinary dysfunction was defined as ≥50 mL residual urine occurring at least once or no measurement of residual urinary volume. This trial was registered with the UMIN Clinical Trials Registry, number C000000034. RESULTS: In the mesorectal excision alone and the mesorectal excision with lateral lymph node dissection groups, the incidence of early urinary dysfunction were 58% and 59%, respectively. A tumor location in the lower rectum (vs. upper rectum) and a blood loss of ≥500 mL (vs. <500 mL) were associated with an increased risk of early urinary dysfunction. However, only blood loss was independently predictive of early urinary dysfunction (relative risk, 1.25 [95% CI: 1.10-1.55], p = .04). CONCLUSIONS: Mesorectal excision with lateral lymph node dissection is not associated with a significant increase in the incidence of urinary dysfunction. Urinary dysfunction is associated with tumor location and blood loss.

Mesorectal Excision With or Without Lateral Lymph Node Dissection for Clinical Stage II/III Lower Rectal Cancer (JCOG0212): A Multicenter, Randomized Controlled, Noninferiority Trial.

OBJECTIVE: The aim of the study was to confirm the noninferiority of mesorectal excision (ME) alone to ME with lateral lymph node dissection (LLND) in terms of efficacy. BACKGROUND: Lateral pelvic lymph node metastasis is occasionally found in clinical stage II or III lower rectal cancer, and ME with LLND is the standard procedure in Japan. ME alone, however, is the international standard surgical procedure for rectal cancer. METHODS: Eligibility criteria included histologically proven rectal cancer at clinical stage II/III; main lesion located in the rectum, with the lower margin below the peritoneal reflection; no lateral pelvic lymph node enlargement; Peformance Status of 0 or 1; and age 20 to 75 years. Patients were intraoperatively allocated to undergo ME with LLND or ME alone in a randomized manner. The primary endpoint was relapse-free survival, with a noninferiority margin for the hazard ratio of 1.34. Secondary endpoints included overall survival and local-recurrence-free survival. Analysis was by intention to treat. RESULTS: In total, 701 patients were randomized to the ME with LLND (n = 351) and ME alone (n = 350) groups. The 5-year relapse-free survival in the ME with LLND and ME alone groups were 73.4% and 73.3%, respectively (hazard ratio: 1.07, 90.9% confidence interval 0.84-1.36), with a 1-sided P value for noninferiority of 0.0547. The 5-year overall survival, and 5-year local-recurrence-free survival in the ME with LLND and ME alone groups were 92.6% and 90.2%, and 87.7% and 82.4%, respectively. The numbers of patients with local recurrence were 26 (7.4%) and 44 (12.6%) in the ME with LLND and ME alone groups, respectively (P = 0.024). CONCLUSIONS: The noninferiority of ME alone to ME with LLND was not confirmed in the intent-to-treat analysis. ME with LLND had a lower local recurrence, especially in the lateral pelvis, compared to ME alone.

Prognostic and predictive value of extended RAS mutation and mismatch repair status in stage III colorectal cancer.

The prognostic and predictive value of KRAS gene mutations in stage III colorectal cancer is controversial because many recent clinical trials have not involved a surgery-alone arm. Additionally, data on the significance of extended RAS (KRAS/NRAS) mutations in stage III cancer are not available. Hence, we undertook a combined analysis of two phase III randomized trials, in which the usefulness of adjuvant chemotherapy with tegafur-uracil (UFT) was evaluated, as compared with surgery alone. We determined the association of extended RAS and mismatch repair (MMR) status with the effectiveness of adjuvant chemotherapy. Mutations in KRAS exons 2, 3, and 4 and NRAS exons 2 and 3 were detected by direct DNA sequencing. Tumor MMR status was determined by immunohistochemistry. Total RAS mutations were detected in 134/304 (44%) patients. In patients with RAS mutations, a significant benefit was associated with adjuvant UFT in relapse-free survival (RFS) (hazard ratio = 0.49; P = 0.02) and overall survival (hazard ratio = 0.51; P = 0.03). In contrast, among patients without RAS mutations, there was no difference in RFS or overall survival between the adjuvant UFT group and surgery-alone group. We detected deficient DNA MMR in 23/304 (8%) patients. The MMR status was neither prognostic nor predictive for adjuvant chemotherapy. An interaction analysis showed that there was better RFS among patients treated with UFT with RAS mutations, but not for those without RAS mutations. Extended RAS (KRAS/NRAS) mutations are proposed as predictive indicators with respect to the efficacy of adjuvant UFT chemotherapy in patients with resected stage III colorectal cancer.

Inhibition of intestinal polyp growth by oral ingestion of bovine lactoferrin and immune cells in the large intestine.

Studies using animal models have demonstrated that ingestion of bovine lactoferrin (bLF) inhibits carcinogenesis in the colon and other organs of experimental animals. As a result of these studies, a blinded, randomized, controlled clinical trial was conducted in the National Cancer Center Hospital, Tokyo, Japan to determine whether ingestion of bLF had an effect on the growth of colorectal polyps in humans. Patients with colorectal polyps ≤5 mm diameter and likely to be adenomas ingested 0, 1.5, or 3.0 g bLF daily for 1 year. Ingestion of 3.0 g bLF suppressed the growth of colorectal polyps and increased the level of serum human lactoferrin in trial participants 63 years old or younger. The purpose of the present study was to investigate correlations between immune parameters and changes in polyp size. Trial participants with regressing polyps had increased NK cell activity, increased serum hLF levels (indicating increased neutrophil activity), and increased numbers of CD4+ cells in the polyps. These findings are consistent with a correlation between higher immune activity and suppression of colorectal polyps. In addition, participants with regressing polyps had lower numbers of PMNs and increased numbers of S100A8+ cells in the polyps, consistent with a correlation between lower inflammatory potential in the colon and suppression of colorectal polyps. Trial participants ingesting bLF had increased serum hLF levels, a possible increase in systemic NK cell activity, and increased numbers of CD4+ and CD161+ cells in the polyps. Taken together, our findings suggest that bLF suppressed colorectal polyps by enhancing immune responsiveness.

Laparoscopic resection of synchronous colorectal cancers in separate specimens.

INTRODUCTION: Laparoscopic approaches are increasingly being used in patients with colorectal cancer, but the feasibility of laparoscopic resection of synchronous colorectal cancers in separate specimens remains unknown. In such cases, it is necessary to consider the site of port placement, sequence of dissection, choice of specimen extraction sites, specimen handling, and extracorporeal anastomosis sites. Moreover, the need for complete mesenteric dissection in two areas, removal of two separate specimens containing malignancies, and two anastomoses elicit unique questions related to technical considerations. The aim of this study was to determine the feasibility of laparoscopic resection of two separate specimens containing malignancies for multiple synchronous colorectal cancers. METHODS: Between June 2001 and January 2013, 1341 patients with colorectal cancer underwent laparoscopic surgery at our institution. Of them, 11 patients underwent laparoscopy-assisted combined resection of two separate colorectal specimens for multiple synchronous primary colorectal cancers. We retrospectively reviewed their surgical outcomes. RESULTS: All procedures were completed laparoscopically without perioperative mortality. Patients underwent right-sided colon resection for right-sided cancer and left-sided or rectal resection for left-sided colon or rectal cancer. The median duration of surgery was 296 min, and the median blood loss was 65 mL. Median time to first postoperative liquid and solid intake was 1 day and 3 days, respectively. Most patients were discharged on postoperative day 8. With regard to postoperative complications, two patients had a surgical-site infection. CONCLUSION: Laparoscopic resection of two separate colorectal specimens for multiple synchronous primary colorectal cancers is a feasible and safe procedure.

Case-matched comparison of the short-term outcomes between laparoscopic and open abdominoperineal resection for rectal cancer.

PURPOSE: The aim of this study was to evaluate the short-term surgical outcomes of laparoscopic abdominoperineal resection (APR) for rectal cancer, by comparing it with a case-control series of open APR. METHODS: Fourteen patients with rectal cancer who underwent laparoscopic APR between August 2004 and November 2011 were compared with the open APR group of 14 patients matched for age, gender, and surgical procedure. RESULTS: There were no cases of conversion to laparotomy in the laparoscopic APR group and no mortality in either of the groups. The median operation was longer (P = 0.002), but the median amount of blood loss was smaller (P = 0.019), in the laparoscopic APR group. The median length of hospital stay of the laparoscopic APR group was 8 days, shorter than that of the open APR group (16 days, P < 0.001). The changes of the WBC count and serum CRP level after operations were significantly smaller in the laparoscopic APR group (P < 0.05). There were no significant differences between the groups in terms of the perioperative morbidity and readmission rates within 30 days. CONCLUSION: Patients undergoing laparoscopic APR had superior perioperative outcomes to those undergoing open APR, except for the longer operation.

Repeatedly recurrent colon cancer involving the appendiceal orifice after endoscopic piecemeal mucosal resection: a case report.

Local recurrence after endoscopic piecemeal mucosal resection (EPMR) for colorectal tumors is a crucial issue. However, such recurrence is usually detected within one year and cured with additional endoscopic treatment, which makes EPMR acceptable. Herein, we report a rare case of repeatedly recurrent colon cancer involving the appendiceal orifice after EPMR, which was not cured with additional endoscopic treatments. A 67-year-old man was referred to us for endoscopic treatment of a 25 mm cecal tumor spreading to the appendiceal orifice in May 2002. The tumor was resected with EPMR, showing well differentiated intramucosal adenocarcinoma with a positive lateral cut margin of tubular adenoma. Endoscopic surveillance was conducted and the first local recurrence was detected in August 2006. Although we resected it endoscopically, the second local recurrence was found in September 2007 and we removed it with endoscopic resection again. However, the third local recurrence was detected in March 2008. Although endoscopic resection was performed also for the third recurrence, curative resection was not achieved. In February 2009, laparoscopic assisted colectomy was performed and histopathological examination showed well differentiated adenocarcinoma with deep submucosal invasion. This case is important in considering indication for endoscopic resection in colorectal tumors involving the appendiceal orifice.

Induction of the stem-like cell regulator CD44 by Rho kinase inhibition contributes to the maintenance of colon cancer-initiating cells.

The difficulty in expanding cancer-initiating cells in vitro is one of major obstacles for their biochemical characterization. We found that Rho kinase (ROCK) inhibitors as well as blebbistatin, a myosin II inhibitor, greatly facilitated the establishment of spheroids from primary colon cancer. The spheroid cells expressed cancer stem cell markers, showed the ability to differentiate, and induced tumors in mice. The spheroids were composed of cells that express various levels of CD44, whereas CD44(high) cells were associated with increased sphere-forming ability, expression of the activating form of ß-catenin, and elevated levels of glycolytic genes, CD44(-/low) cells showed increased levels of differentiation markers and apoptotic cells. The spheroid cells expressed variant forms of CD44 including v6, and the induction of the variants was associated with the activating phosphorylation of c-Met. As expected from the predicted hierarchy, CD44(high) cells differentiated into CD44(-/low) cells. Unexpectedly, a fraction of CD44(-/low) cells generated CD44(high) cells, and the ROCK inhibitor or blebbistatin primed the transition by inducing CD44 expression. We propose that the transition from CD44(-/low) to CD44(high) state helps to maintain a CD44(high) fraction and the tumorigenic diversity in colon cancer.

Risk factors for anastomotic leakage after laparoscopic surgery for rectal cancer using a stapling technique.

PURPOSE: This study evaluated the risk factors for anastomotic leakage after laparoscopic surgery for rectal cancer using a stapling technique. METHODS: The total prospective registry of 111 patients with rectal cancer who initially underwent laparoscopic low anterior resection using a stapling technique was reviewed. Univariate and multivariate analyses were carried out to identify relevant risk factors. RESULTS: Overall anastomotic leakage rate was 5.4% (6/111). Univariate analysis demonstrated that body mass index (BMI) (P=0.0377) was significantly associated with anastomotic leakage. After univariate analysis, the variables of BMI and the size of the circular stapler (P=0.0923) were selected for multivariate analysis, as their P values were <0.2, and multivariate analysis demonstrated that BMI was independently predictive of developing anastomotic leakage (P=0.0458). CONCLUSIONS: Laparoscopic surgery for rectal cancer using a stapling technique can be performed safely without increasing the risk of anastomotic leakage, and increased BMI might be a potential risk factor for anastomotic leakage.

Histone lysine methyltransferase SETD8 promotes carcinogenesis by deregulating PCNA expression.

Although the physiologic significance of lysine methylation of histones is well known, whether lysine methylation plays a role in the regulation of nonhistone proteins has not yet been examined. The histone lysine methyltransferase SETD8 is overexpressed in various types of cancer and seems to play a crucial role in S-phase progression. Here, we show that SETD8 regulates the function of proliferating cell nuclear antigen (PCNA) protein through lysine methylation. We found that SETD8 methylated PCNA on lysine 248, and either depletion of SETD8 or substitution of lysine 248 destabilized PCNA expression. Mechanistically, lysine methylation significantly enhanced the interaction between PCNA and the flap endonuclease FEN1. Loss of PCNA methylation retarded the maturation of Okazaki fragments, slowed DNA replication, and induced DNA damage, and cells expressing a methylation-inactive PCNA mutant were more susceptible to DNA damage. An increase of methylated PCNA was found in cancer cells, and the expression levels of SETD8 and PCNA were correlated in cancer tissue samples. Together, our findings reveal a function for lysine methylation on a nonhistone protein and suggest that aberrant lysine methylation of PCNA may play a role in human carcinogenesis.

Postoperative morbidity and mortality after mesorectal excision with and without lateral lymph node dissection for clinical stage II or stage III lower rectal cancer (JCOG0212): results from a multicentre, randomised controlled, non-inferiority trial.

BACKGROUND: Mesorectal excision is the international standard surgical procedure for lower rectal cancer. However, lateral pelvic lymph node metastasis occasionally occurs in patients with clinical stage II or stage III rectal cancer, and therefore mesorectal excision with lateral lymph node dissection is the standard procedure in Japan. We did a randomised controlled trial to confirm that the results of mesorectal excision alone are not inferior to those of mesorectal excision with lateral lymph node dissection. METHODS: This study was undertaken at 33 major hospitals in Japan. Eligibility criteria included histologically proven rectal cancer of clinical stage II or stage III, with the main lesion located in the rectum with the lower margin below the peritoneal reflection, and no lateral pelvic lymph node enlargement. After surgeons had confirmed macroscopic R0 resection by mesorectal excision, patients were intraoperatively randomised to mesorectal excision alone or with lateral lymph node dissection. The groups were balanced by a minimisation method according to clinical N staging (N0 or N1, 2), sex, and institution. Allocated procedure was not masked to investigators or patients. This study is now in the follow-up stage. The primary endpoint is relapse-free survival and will be reported after the primary analysis planned for 2015. Here, we compare operation time, blood loss, postoperative morbidity (grade 3 or 4), and hospital mortality between the two groups. Analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00190541. FINDINGS: 351 patients were randomly assigned to mesoretcal excision with lateral lymph node dissection and 350 to mesorectal excision alone, between June 11, 2003, and Aug 6, 2010. One patient in the mesorectal excision alone group underwent lateral lymph node dissection, but was analysed in their assigned group. Operation time was significantly longer in the mesorectal excision with lateral lymph node dissection group (median 360 min, IQR 296-429) than in the mesorectal excision alone group (254 min, 210-307, p<0·0001). Blood loss was significantly higher in the mesorectal excision with lateral lymph node dissection group (576 mL, IQR 352-900) than in the mesorectal excision alone group (337 mL, 170-566; p<0·0001). 26 (7%) patients in the mesorectal excision with lateral lymph node dissection group had lateral pelvic lymph node metastasis. Grade 3-4 postoperative complications occurred in 76 (22%) patients in the mesorectal excision with lateral lymph node dissection group and 56 (16%) patients in the mesorectal excision alone group. The most common grade 3 or 4 postoperative complication was anastomotic leakage (18 [6%] patients in the mesorectal excision with lateral lymph node dissection group vs 13 [5%] in the mesorectal excision alone group; p=0·46). One patient in the mesorectal excision with lateral lymph node dissection group died of anastomotic leakage followed by sepsis. INTERPRETATION: Mesorectal excision with lateral lymph node dissection required a significantly longer operation time and resulted in significantly greater blood loss than mesorectal excision alone. The primary analysis will help to show whether or not mesorectal excision alone is non-inferior to mesorectal excision with lateral lymph node dissection. FUNDING: National Cancer Center, Ministry of Health, Labour and Welfare of Japan.

Prognostic factors of rectal cancer patients with lateral pelvic lymph node metastasis.

BACKGROUND/AIMS: We examined the clinicopathological characteristics of rectal cancer patients with lateral pelvic lymph node (LPLN) metastasis in order to clarify their associated prognostic factors. METHODOLOGY: A total of 91 rectal cancer patients with LPLN metastasis who underwent curative resection at the National Cancer Center Hospital between 1985 and 2004 were reviewed. RESULTS: The five-year overall survival rate and disease-free survival rate of the studied patient were 39% and 27%, respectively. Univariate analysis showed that tumor differentiation, lymphatic invasion, venous invasion, mesenteric lymph node status and LPLN status were significant prognostic factors. Multivariate analysis showed that tumor differentiation, mesenteric lymph node status and LPLN status were significant prognostic factors. Among 15 patients with LPLN metastasis and without mesenteric lymph node metastasis, 11 patients (73.3%) with one or two LPLN metastases survived more than five years. Among 12 patients with four or more LPLN metastases, two(16.7%) survived more than five years. CONCLUSIONS: Tumor differentiation, mesenteric lymph node status and LPLN status are significant prognostic factors of patients with LPLN metastasis. Because some patients with LPLN metastasis survive for a long period, LPLN dissection should be considered for them.

Dome-type carcinoma of the colon; a rare variant of adenocarcinoma resembling a submucosal tumor: a case report.

BACKGROUND: Dome-type carcinoma (DC) is a distinct variant of colorectal adenocarcinoma and less than 10 cases have been described in the literature. Most of the previously reported cases were early lesions and no endoscopic observations have been described so far. We herein report a case of a DC invading the subserosal layer, including endoscopic findings. CASE PRESENTATION: A highly elevated lesion in the transverse colon was diagnosed by colonoscopy in a 77-year-old man. The tumor appeared to be similar to a submucosal tumor (SMT), however, a demarcated area of reddish and irregular mucosa was observed at the top of the tumor. There were no erosions or ulcers. Laparoscopic-assisted right hemicolectomy was performed and pathological examination revealed a well-circumscribed tumor invading the subserosal layer. The tumor was a well-differentiated adenocarcinoma associated with a dense lymphocytic infiltration and showed expansive growth. The overlying mucosal layer showed high-grade dysplasia. CONCLUSION: The present lesion was diagnosed as a DC of the colon invading the subserosal layer. Because the association of mucosal dysplasia is common in DCs, the detection of dysplastic epithelium would be important to discriminate DCs from SMTs.

Clinicopathological characteristics and prognostic factors of advanced colorectal mucinous adenocarcinoma.

AIMS: Mucinous adenocarcinoma (MUC) is a histological variant of colorectal adenocarcinoma. The aim of the present study was to characterize clinicopathological features and identify prognostic factors of MUCs. METHODS AND RESULTS: A total of 181 patients with MUC who underwent surgery between 1975 and 2003 were reviewed. The clinicopathological features of these patients were compared with those of 4125 non-MUC patients. Univariate and multivariate analyses were conducted to identify significant prognostic factors in 102 patients with pT3 or pT4 tumour who underwent curative surgery. Patients with MUCs tended to present with more advanced clinical stages. The overall 5-year survival rate of MUC patients was lower than that of non-MUC patients; however, no prognostic difference was found when patients with the same clinical stages were compared. Multivariate analysis revealed male sex, bowel obstruction and infiltrating growth type as independent prognostic factors. Five-year cancer-specific survival rates for MUC patients with ≤1, 2 and 3 risk factors identified by multivariate analysis were 95.5%, 52.1% and 0.0%, respectively (P < 0.001). CONCLUSIONS: Mucinous adenocarcinoma represents a distinct clinicopathological entity. Sex, bowel obstruction and growth patterns might be useful prognostic factors to identify patients with a high risk of recurrence after curative resection of advanced MUCs.

Short-term outcomes of laparoscopic intersphincteric resection for lower rectal cancer and comparison with open approach.

BACKGROUND/AIMS: To evaluate the short-term surgical outcomes of laparoscopic intersphincteric resection (ISR) for lower rectal cancer, and to compare them with a case-control series of open ISR. METHODS: Between July 2002 and March 2011, 29 patients with lower rectal cancer underwent laparoscopic ISR, and 22 of 29 patients who underwent laparoscopic ISR were compared with the control open ISR group of patients matched for age, gender, operative procedure and pathological stage. RESULTS: There was no perioperative mortality, 8 complications occurred in 7 patients, and the morbidity rate was 24.1% (7/29). Leakage occurred in 1 patient (3.4%) in the laparoscopic ISR group. Regarding the matched case-control study, the operative time was significantly longer (p = 0.0007), but blood loss was significantly lower (p = 0.0003) in the laparoscopic ISR group. The median postoperative hospital stay was 8 days in the laparoscopic ISR group, which was significantly shorter than in the open ISR group (14 days). Postoperative complication rates were similar. In the laparoscopic ISR group, the levels of C-reactive protein on postoperative days 1-3 were significantly lower than in the open ISR group. CONCLUSIONS: Laparoscopic ISR for lower rectal cancer provides benefits in the early postoperative period without increasing morbidity or mortality.

[Treatment of lateral node metastasis from lower rectal cancer].

Lateral lymphatics of the rectum originate in the area where branches of the inferior hypogastric plexus and the middle rectal vessels from the internal iliac vessels enter the mesorectum below the level of the peritoneal reflection in the pelvis, then reach the bifurcation of iliac vessels along the internal iliac vessels. Among lateral lymph nodes, the middle rectal, obturator, and internal iliac lymph nodes are important from the viewpoint of both the incidence of metastais and treatment effects. Although total mesorectal excision (TME) had become the standard surgical treatment for rectal cancer by the 1990s, this technique does not treat lateral node metastasis. A randomized clinical trial of TME versus D3 lymphadenectomy (JCOG0212) was started in 2003, and the registration of 701 patients with lower rectal cancer was completed in August 2010. The results of this clinical trial are highly anticipated. In Japan, where the rate of local recurrence after surgery is low, patients at high risk of local recurrence such as those with lateral node metastasis, T4 disease, and multiple lymph node metastases in the mesorectum should be selected to receive preoperative chemoradiation. Japanese surgeons who treat rectal cancers are in an advantageous position because they have the additional measure of lateral node dissection along with TME and chemoradiotherapy.

Validation of the histone methyltransferase EZH2 as a therapeutic target for various types of human cancer and as a prognostic marker.

The emphasis in anticancer drug discovery has always been on finding a drug with great antitumor potential but few side-effects. This can be achieved if the drug is specific for a molecular site found only in tumor cells. Here, we find the enhancer of zeste homolog 2 (EZH2) to be highly overexpressed in lung and other cancers, and show that EZH2 is integral to proliferation in cancer cells. Quantitative real-time PCR analysis revealed higher expression of EZH2 in clinical bladder cancer tissues than in corresponding non-neoplastic tissues (P < 0.0001), and we confirmed that a wide range of cancers also overexpress EZH2, using cDNA microarray analysis. Immunohistochemical analysis showed positive staining for EZH2 in 14 of 29 cases of bladder cancer, 135 of 292 cases of non-small-cell lung cancer (NSCLC), and 214 of 245 cases of colorectal cancer, whereas no significant staining was observed in various normal tissues. We found elevated expression of EZH2 to be associated with poor prognosis for patients with NSCLC (P = 0.0239). In lung and bladder cancer cells overexpressing EZH2, suppression of EZH2 using specific siRNAs inhibited incorporation of BrdU and resulted in significant suppression of cell growth, even though no significant effect was observed in the normal cell strain CCD-18Co, which has undetectable EZH2. Because EZH2 expression was scarcely detectable in all normal tissues we examined, EZH2 shows promise as a tumor-specific therapeutic target. Furthermore, as elevated levels of EZH2 are associated with poor prognosis of patients with NSCLC, its overexpression in resected specimens could prove a useful molecular marker, indicating the necessity for a more extensive follow-up in some lung cancer patients after surgical treatment.