Hayato Kan

preoperative Oral Immune-enhancing Nutritional Supplementation Corrects Th1/th2 Imbalance in Patients Undergoing Elective Surgery for Colorectal Cancer

PurposeRecent studies have shown that the type 1/2 CD4+ T cell (Th1/Th2) balance shifts toward Th2 dominance in cancer-bearing state or by surgical stress. Perioperative immunonutrition is reported to improve the outcome in patients with gastrointestinal cancer. This study was designed to investigate whether preoperative immunonutrition corrects the impaired Th1/Th2 balance in the perioperative period.MethodsThirty-six patients with colorectal cancer were prospectively divided into two groups as follows: preoperative oral intake supplementation with a formula enriched with arginine, ω-3 fatty acids and ribonucleic acid for five days (supplemented group; n = 19); and (control group; n = 17). Blood sampling was performed before supplementation, on the morning of surgery, and 3, 7, and 14 days postoperatively. The proportions of CD4+ T cells producing intracellular cytokines (interferon-γ and interleukin-4) were measured by flow cytometry.ResultsIn the preoperative period, the proportions of CD4+ T cells producing interleukin-4 significantly decreased and Th1/Th2 ratio significantly increased on the morning of surgery compared with those before supplementation. In the postoperative period, the proportions of CD4+ T cells producing interferon-γ in both groups maintained the preoperative level. The proportions of CD4+ T cells producing interleukin-4 in the control group showed a gradual increase from the preoperative level, which implies Th2 dominant shift. In contrast, the supplemented group maintained the preoperative level of Th1/Th2 ratio.ConclusionsPreoperative immunonutrition corrects impaired Th1/Th2 balance in both cancer-bearing state and the postoperative period. This correction may be one of the important determinants of the clinical benefits of immunonutrition.

Utility of KRAS mutation detection using circulating cell‐free DNA from patients with colorectal cancer

In this study, we evaluated the clinical utility of detecting KRAS mutations in circulating cell‐free (ccf)DNA of metastatic colorectal cancer patients. We prospectively recruited 94 metastatic colorectal cancer patients. Circulating cell‐free DNA was extracted from plasma samples and analyzed for the presence of seven KRAS point mutations. Using the Invader Plus assay with peptide nucleic acid clamping method and digital PCR, KRAS mutations were detected in the ccfDNA in 35 of 39 patients previously determined to have primary tumors containing KRAS mutations using the Luminex method, and in 5 of 55 patients with tumors containing wild‐type KRAS. Curative resection was undertaken in 7 of 34 patients with primary and ccfDNA KRAS mutations, resulting in the disappearance of the mutation from the cell‐free DNA in five of seven patients. Three of these patients had tumor recurrence and KRAS mutations in their ccfDNA reappeared. Epidermal growth factor receptor blockade was administered to 24 of the KRAS tumor wild‐type patients. Of the 24 patients with wild‐type KRAS in their primary tumors, three patients had KRAS mutations in their ccfDNA and did not respond to treatment with epidermal growth factor receptor (EGFR) blockade. We also detected a new KRAS mutation in five patients during chemotherapy with EGFR blockade, before disease progression was detectable with imaging. The detection of KRAS mutations in ccfDNA is an attractive approach for predicting both treatment response and acquired resistance to EGFR blockade, and for detecting disease recurrence.

1,2-Dimethylhydrazine(DMH)誘発ラット大腸癌に対する緑茶ポリフェノールの影響

We studied the anti-tumor effect of green tea polyphenol fraction (Sunphenon, SF: provided by Taiyo Kagaku Inc., Mie, Japan) on DMH-induced colorectal carcinogenesis in male Wistar rats. DMH was subcutaneously administered weekly at 20 mg/kg for 14 weeks. The rats in group I (20 rats) were given tap water for the whole of the study period. The rats in group II (15 rats) were given tap water from weeks 0-14, and 0.1% SF from weeks 15-35. The rats in group III (21 rats) were given 0.1% SF during the whole period. The rats were sacrificed at week 35. The cecal contents were aseptically removed and examined microbiologically to obtain the counts of four bacteria species (including Clostridium perfringens) per 1 g of cecal contents. The incidence of tumors production was significantly decreased (Group I: 100% vs Group II: 57.1%, Group III: 62.5%, p < 0.05), and the frequency of occurrence of C. perfringens (which is thought to yield harmful products which may be carcinogenic) was decreased in the SF-treated groups. These results suggest that SF prevents DMH-induced carcinogenesis in rats, and that its effect may be somehow related to its ability to preserve the composition of the colonic microflora.

Successful Treatment of Necrotizing Fasciitis after Rectal Surgery with the Application of a Negative-pressure Wound Therapy: A Case Study

INTRODUCTION Necrotizing fasciitis (NF) is an aggressive soft tissue infection that involves the deep fascia and is characterized by the extensive deterioration of the surrounding tissue. Immediate recognition and aggressive treatment, including debridement and systemic antibiotics, are mandatory for the successful management of NF. Following radical debridement, closure of the remaining wound can pose significant reconstructive challenges. Accumulating evidence indicates that application of negative-pressure wound therapy (NPWT) is useful in the treatment of patients with severe acute complex wounds, including NF. CASE PRESENTATION A 58-year-old man who had undergone surgical resection for rectal carcinoma followed by chemo-radiation therapy developed NF of the pelvis and thigh three years after the surgical procedure. Following extensive debridement, a VAC system was applied to the large open wound and successfully contributed to wound bed cleansing, which was followed by surgery for skin grafting. CONCLUSION This case demonstrates the successful management of a complex and potentially lethal wound of the perineum to lower leg with debridement and skin grafting as well as with the application of the VAC system.

Superior mesenteric artery syndrome treated with single-incision laparoscopy-assisted duodenojejunostomy

Superior mesenteric artery (SMA) syndrome is an uncommon disease resulting from compression and partial obstruction of the third portion of the duodenum from the SMA. A 77‐year‐old man, who did not have a history of surgery, experienced repeated vomiting and developed abdominal distension. Abdominal CT showed a narrowed third portion of the duodenum, with a distended stomach and proximal duodenum. The patient was diagnosed as having SMA syndrome and was initially treated conservatively, but his condition did not improve. Single‐incision laparoscopy‐assisted duodenojejunostomy was performed. The patient recovered well and was discharged from hospital on postoperative day 8. Laparoscopic treatment is feasible for the treatment of SMA syndrome given its safety and minimal invasiveness. This is a report of the first case of single‐incision laparoscopy‐assisted duodenojejunostomy. This procedure is safer and less invasive than a conventional laparoscopic approach in a patient with SMA syndrome.

Surgical Specimens of Colorectal Cancer Fixed with PAXgene Tissue System Preserve High-Quality RNA.

BACKGROUND RNA analysis of surgical specimens is one of the most useful methods for exploring biomarkers of advanced cancer. The most readily available source for RNA is formalin-fixed, paraffin-embedded (FFPE) specimens, but RNA isolated from FFPE tissue is of limited use. The PAXgene Tissue (PAX) system is a formalin-free system designed to improve the quality of molecular analysis without diminishing the quality of histopathological analysis. In this human colorectal cancer tissue study, we aimed to evaluate whether surgical specimens fixed with PAX can preserve high-quality RNA in comparison with FFPE and fresh-frozen tissue specimens. METHODS Ten consecutive advanced colorectal cancer patients undergoing colectomy were examined. Each specimen was processed in three ways: as frozen tissue, as PAX-fixed tissue, and as formalin-fixed tissue. RNA integrity numbers (RINs) were assessed using an Agilent Bioanalyzer. RNA transcript levels and stability were investigated by quantitative real-time PCR. We also evaluated the immunohistochemical intensity of Ki-67, CEA, and EGFR in the PAX samples. RESULTS The average RINs of RNA extracted from frozen and PAX samples were significantly higher than those from FFPE samples (p < 0.001). The cycle threshold (Ct) values were similar in PAX and frozen samples, but significantly increased in FFPE samples (p < 0.001). Most of the ΔCt values in the PAX samples did not differ significantly from those in the matched frozen samples. On the other hand, most of the ΔCt values in the FFPE samples differed significantly from those in the matched frozen samples. The immunohistochemical intensity in the PAX samples was well preserved. CONCLUSIONS The quality of RNA extracted from PAX samples may be slightly inferior to that from frozen samples, but is greatly superior to that from FFPE samples.

Gene profiling and bioinformatics analyses reveal time course differential gene expression in surgically resected colorectal tissues

It has previously been reported that gene profiles in surgically-resected colorectal cancer tissues are altered over time possibly due to the different tissue-acquisition methods and sample extraction timing that were used. However, the changes that occur are still not clearly understood. In the present study, time-dependent changes in gene expression profiling in colorectal surgical specimens were analyzed. Normal and tumor tissues at several time-points (0, 30, 60 and 120 min) were extracted, and RNA quality, microarray experiments, quantitative PCR and bioinformatics clustering were performed. Although RNA integrity was preserved 2 h after resection, inherent increased/decreased gene expression was observed from 30–120 min in approximately 10% of genes. Bioinformatics clustering could not distinguish case-by-case, probably due to gene profiling changes. Irregular changes in gene expression after surgical resection were found, which could be a crucial confounding factor for quantitative analyses.

Combined use of preoperative lymphocyte counts and the post/preoperative lymphocyte count ratio as a prognostic marker of recurrence after curative resection of stage II colon cancer

Purpose Diagnostic markers for recurrence of colorectal cancer have not been established. The aim of the present study was to identify new diagnostic markers for recurrence after curative surgery of stage II colon cancer. Materials and Methods In this study, the prognostic values of the preoperative lymphocyte count and the post/preoperative lymphocyte count ratio (PPLR) were evaluated in 142 patients with localized colon cancer treated with surgery at a single medical center. The associations of patient demographics, blood chemistry, and serum biochemical indices with recurrence-free survival (RFS) and cancer-specific survival (CSS) were examined by univariate and multivariate analyses. Results Receiver operating characteristic (ROC) curve analysis showed that the optimal cut-off values of the lymphocyte count and PPLR were, respectively, 1555.2/μl and 1.151 for RFS. On univariate analysis, tumor depth of invasion, carbohydrate antigen 19-9 (CA19-9), and preoperative low lymphocyte count (≤1555.2/μl) were all correlated with poorer RFS (p < 0.05). On multivariate analysis, T4, low lymphocyte count, and low PPLR were independent predictors of poor RFS. Furthermore, the patients were categorized into four categories based on preoperative lymphocyte count high/low and PPLR high/low. Patients with a low preoperative lymphocyte count and low PPLR had the poorest RFS and CSS compared to the other patients. Conclusion The combination of the preoperative lymphocyte count and the PPLR appears to be a potential marker for predicting recurrence of stage II colon cancer.

Primary small intestinal volvulus after laparoscopic rectopexy for rectal prolapse: Volvulus after laparoscopic rectopexy

Primary small intestinal volvulus is defined as torsion in the absence of congenital malrotation, band, or postoperative adhesions. Its occurrence as an early postoperative complication is rare. A 40‐year‐old woman presented with rectal prolapse, and laparoscopic rectopexy was uneventfully performed. She could not have food on the day after surgery. She started oral intake on postoperative day 3 but developed abdominal pain after the meal. Contrast‐enhanced CT revealed torsion of the small intestinal mesentery. An emergent laparotomy showed small intestinal volvulus, without congenital malformation or intestinal adhesions. We diagnosed it as primary small intestinal volvulus. The strangulated intestine was resected, and reconstruction was performed. The patient recovered uneventfully after the second surgery. To the best of our knowledge, this is the first report of primary small intestinal volvulus occurring after rectopexy for rectal prolapse. Primary small intestinal volvulus could be a postoperative complication after laparoscopy.

Abstract 3134: Prediction of early recurrence after resection of metastatic liver tumors from colorectal cancer using circulating cell-free DNA

Background: We have reported that the amount of total circulating cell-free DNA (ccfDNA) increases with tumor growth and decreases upon tumor shrinkage. However, adverse effects of drugs and surgical stress can increase total ccfDNA because ccfDNA is derived from both normal and cancer cells. Thus, the ability to determine how much ccfDNA is derived from cancer cells is a critical issue. It has been reported that the length of ccfDNA derived from cancer cells is greater than 200 bp while that from normal cells undergoing apoptosis is less than 200 bp. Furthermore, the ratio of ccfDNA to β-globin reflects the amount of mitochondrial DNA derived from normal cells undergoing stress-induced apoptosis. We developed a new biomarker readout, the LINE-1 long fragment (longer than 200 bp) to β-globin ratio (LBR), based on this principle. In this study, we evaluated the clinical utility of the LBR to detect early recurrence of liver metastasis from colorectal cancer after liver resection. Methods: We enrolled 20 patients who underwent curative liver resection of metastatic liver tumors from colorectal cancer. Total ccfDNA and LBR were measured pre-surgery, and at 1 week and 1 month post-surgery. ccfDNA was purified from 1 mL serum using the QIAamp Circulating Nucleic Acid Kit. Total ccfDNA was measured using Qubit Fluorometer. LINE-1 long fragment and β-globin in ccfDNA were measured using real time PCR. The Ethics Review Committee of our institution approved the study protocol. Written informed consent was obtained from each patient. Results: We completed 1-year follow-up in 13 of 20 patients. Recurrence was detected in 7 patients and no signs of recurrence were detected in the other 6. Total ccfDNA increased 1 week after surgery in all 13 patients, which could have been caused by surgical stress. Total ccfDNA 1 month after surgery increased in 5 of 7 patients with recurrence. Total ccfDNA 1 month after surgery increased in 3 of 6 patients without recurrence. The 3 patients with increased ccfDNA had post-operative complications or drug-induced liver dysfunction. Notably, LBR increased in the 7 patients with recurrence and decreased in the 6 patients without recurrence 1 month post-surgery. Conclusion: LBR has potential as a novel biomarker readout for early detection of recurrence after liver resection of metastatic liver tumors from colorectal cancer. Citation Format: Takuma Iwai, Takeshi Yamada, Hayato Kan, Michihiro Koizumi, Seiichi Shinji, Yasuyuki Yokoyama, Goro Takahashi, Shiro Kitano, Masato Nakayama, Zenya Naito, Keiichiro Ohta, Eiji Uchida. Prediction of early recurrence after resection of metastatic liver tumors from colorectal cancer using circulating cell-free DNA. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3134.