Analysis of colorectal cancer-related mutations by liquid biopsy: Utility of circulating cell-free DNA and circulating tumor cells.

We recruited 56 colorectal cancer patients and compared the mutational spectrum of tumor tissue DNA, circulating cell-free DNA (ccfDNA) and circulating tumor cell (CTC) DNA (ctcDNA) to evaluate the potential of liquid biopsy to detect heterogeneity of cancer. Tumor tissue DNA, ccfDNA, and ctcDNA were extracted from each patient and analyzed using next-generation sequencing (NGS) and digital PCR. To maximize yields of CTC, three antibodies were used in the capture process. From 34 untreated patients, 53 mutations were detected in tumor tissue DNA using NGS. Forty-seven mutations were detected in ccfDNA, including 20 not detected in tissues. Sixteen mutations were detected in ctcDNA, including five not detected in tissues. In 12 patients (35.3%), mutations not found in tumor tissues were detected by liquid biopsy: nine (26.5%) in ccfDNA only and three (8.8%) in ctcDNA only. Combination analysis of the two liquid biopsy samples increased the sensitivity to detect heterogeneity. From 22 stage IV patients with RAS mutations in their primary tumors, RAS mutations were detected in 14 (63.6%) ccfDNA and in eight (36.4%) ctcDNA using digital PCR. Mutations not detected in primary tumors can be identified in ccfDNA and in ctcDNA, indicating the potential of liquid biopsy in complementing gene analysis. Combination analysis improves sensitivity. Sensitivity to detect cancer-specific mutations is higher in ccfDNA compared with ctcDNA.

Establishment and characterization of a novel neuroendocrine carcinoma cell line derived from a human ascending colon tumor.

The incidence of rare neuroendocrine tumors (NET) is rapidly increasing. Neuroendocrine carcinoma (NEC) is a NET with poorly differentiated histological features, high proliferative properties and associated poor prognoses. As these carcinomas are so rare and, thus, affect only a small number of patients allowing for few cell lines to be derived from patient biopsies, the histological, immunohistochemical, and clinical characteristics associated with colorectal NEC and NEC in other organs have yet to be clearly defined. Herein, we describe the establishment of a novel NEC cell line (SS-2) derived from a tumor resection of the ascending colon from a 59-year-old Japanese woman. The histological, electron microscopic and immunohistochemical features of chromogranin A (CgA) as well as confirmation of synaptophysin positivity in this tumor were typical of those commonly observed in surgically resected colorectal NEC. Further, the Ki-67 labeling index of the resected tumor was >20% and, thus, the tumor was diagnosed as an NEC of the ascending colon. The SS-2 cell line maintained characteristic features to those of the resected tumor, which were further retained following implantation into subcutaneous tissues of nude mice. Additionally, when SS-2 cells were seeded into ultra-low attachment plates, they formed spheres that expressed higher levels of the cancer stem cell (CSC) marker CD133 compared to SS-2 cells cultured under adherent conditions. SS-2 cells may, therefore, contribute to the current knowledge on midgut NEC biological function while providing a novel platform for examining the effects of colorectal NEC drugs, including CSC.

Farnesoid X receptor induces cell death and sensitizes to TRAIL-induced inhibition of growth in colorectal cancer cells through the up-regulation of death receptor 5.

Farnesoid X receptor (FXR) exhibits critical anti-cancer functions in several types of cancer, including colorectal cancer, in vitro and in vivo. However, the underlying mechanism remains unclear. We evaluated pharmacological activation of FXR with the synthetic agonist GW4064 using comprehensive proteomic analysis in colorectal cancer cell lines (HCT116, SW480, and DLD1). Among the commonly detected proteins in all three cell lines, death receptor 5 (DR5) was the most up-regulated protein, and key autophagy-related proteins, such as microtubule-associated protein 1 light chain 3 alpha/beta (MLP3A/3B) and p62 sequestosome-1 (SQSTM), were also differentially expressed. Western blot analysis showed that GW4064 stimulation induced activation of the extrinsic death signaling pathway in all cell lines and induced activation of the intrinsic death signaling pathway in DLD1 cells. Western blotting showed that DR5 up-regulation was associated with inhibition of autophagic activity. These results suggest that FXR activation induced DR5 up-regulation through inhibition of autophagic activity and the DR5-related death signaling pathway. In addition, DR5 selective ligand, also known as TRAIL, has been widely used for anti-cancer treatment in several clinical trials. Co-treatment of TRAIL with GW4064 synergistically inhibited colorectal cancer cell proliferation as compared with single treatments. To the best of our knowledge, our results provide novel insights into FXR function in cancer cell lines. These findings may contribute to a new therapeutic strategy for colorectal cancer.

Liquid Biopsy for the Management of Patients with Colorectal Cancer.

BACKGROUND: Liquid biopsy is a collective term that refers to the analysis of tumor-derived biomarkers isolated from biological fluids of cancer patients. Recently, many authors reported the usefulness of liquid biopsy for the management of malignancy. Summary and Key Messages: The peripheral blood of cancer patients is a pool of cells and/or cell products derived from the primary or metastatic tumor, including circulating tumor cells (CTCs), circulating free (cf) DNA or RNA, and exosomes containing proteins, nucleic acids, and lipids. CTCs are tumor cells that can be isolated from peripheral blood. Free circulating DNA with a tumor-specific mutation is called circulating tumor DNA (ctDNA). Some patients who undergo curative surgery experience recurrent disease, which can be due to the presence of minimal residual disease (MRD). Thus, MRD indicates a high risk of relapse. Detection of ctDNA or CTC after surgery is a direct proof of MRD. Molecular volume (e.g., the number of CTCs and level of ctDNA) might reflect tumor burden, thus high molecular volume may indicate poor prognosis. The most notable application of liquid biopsy in cancer is to understand spatial and temporal heterogeneities. Heterogeneity is one of the causes of refractoriness and hampers prediction of chemotherapeutic effect. Emerging mutations that are not present in primary tumors but are found in their metastases can be detected in ctDNA. Some colorectal cancer patients with wild-type RAS do not respond to epidermal growth factor receptor blockade. In a subset of these patients, RAS mutation is detected in ctDNA, indicating heterogeneity.

[Effectiveness of Chemoradiotherapy for the Treatment of Local Recurrence in Rectal Cancer-A Case Report].

Chemoradiotherapy(CRT)for locally recurrent rectal cancer can shrink the tumor and permit R0 resection; however, its effectiveness and safety have not been established. Herein, we report a case of a 60s man with locally recurrent rectal cancer invading the surrounding organs who was administered CRT followed by R0 laparoscopic-assisted abdominoperineal resection( APR). Local recurrence was detected 11 months after laparoscopic-assisted low anterior resection(pT3N0M0, pStage Ⅱ). After tumor shrinkage by CRT(capecitabine 3,000mg/day plus 45 Gy/25 Fr), laparoscopic-assisted APR was performed. The pathological findings showed a pathological complete response(pCR). The patient had not experienced recurrent disease at 6 months after the second surgery. CRT may improve the prognosis of patients with locally recurrent rectal cancer, especially those with possibly unresectable tumors.

[Consideration for Prognostic Indicators of Ovarian Metastasis of Colorectal Cancer].

Ovarian metastasis of colorectal cancer is associated with poor prognosis. Recent advances in chemotherapy may improve this prognosis. In this retrospective study, we evaluated indicators of poor prognosis for ovarian metastasis of colorectal cancer. Twenty patients, who were diagnosed with ovarian metastasis of colorectal cancer from April 2000 to December 2017, were enrolled. Oophorectomy was performed in 18 of the 20 patients. Postoperative chemotherapy was provided to 13 patients, and molecular targeting agents were administered in 5 patients. Metastases to other organs besides the ovaries, premenopausal condition, undifferentiated histologic type of the primary tumor, and no resection of ovarian metastases were identified as indicators of poor prognosis. The 3-year survival rate was 15%, and the 5-year survival rate was 0%. In conclusion, oophorectomy can improve the prognosis of patients with ovarian metastasis of colorectal cancer. However, prognostic improvement due to molecular target agents was not shown.

Soft-Hair-Enhanced Entanglement Beyond Page Curves in a Black Hole Evaporation Qubit Model.

We propose a model with multiple qubits that reproduces the thermal properties of four-dimensional Schwarzschild black holes (BHs) by simultaneously taking account of the emission of Hawking particles and the zero-energy soft-hair evaporation at the horizon. The results verify that the entanglement entropy between a qubit and other subsystems, including emitted radiation, is much larger than the BH entropy analogue of the qubit, as opposed to the Page curve prediction. Our result suggests that early Hawking radiation is entangled with soft hair and that late Hawking radiation can be highly entangled with the degrees of freedom of a BH, avoiding the emergence of a firewall at the horizon.

Male sex and history of ischemic heart disease are major risk factors for anastomotic leakage after laparoscopic anterior resection in patients with rectal cancer.

BACKGROUND: Anastomotic leakage (AL) is the most serious and common complication of surgery for rectal cancer, and associated risk factors remain unknown despite developments in laparoscopic surgery. The present study aimed to determine risk factors for AL after laparoscopic anterior resection (AR) of rectal cancer. METHODS: This retrospective cohort study extracted information from a prospective database of all consecutive colorectal resections that proceeded at Nippon Medical School Hospital between January 2011 and December 2015 (n = 865). We identified 154 patients with rectal cancer treated by elective laparoscopic AR with anastomosis using primary double-stapling. Clinical variables and comorbidity, habits, and surgery-related variables were assessed by univariate and multivariate analyses to determine preoperative risk factors for clinical AL. RESULTS: The overall rate of clinical AL was 11.7% (18 of 154 patients), and 5 (27.8%) of 18 patients required revised laparotomy. Data from males were analyzed because AL occurred only in males. Univariate analysis of male patients (n = 100) significantly associated preoperative creatinine values (p = 0.03) and a history of ischemic heart disease (IHD) (p = 0.012) with AL. The frequency of AL tended to increase (p = 0.06) when patients had low AR (p = 0.06) and transanal drainage. Having AL significantly prolonged hospital stays compared with patients without leakage (36.2 vs. 11.1 days; p <  0.01). Multivariate analysis identified a history of IHD (odds ratio [OR], 4.73; 95% confidence interval [CI], 1.27-17.5; p = 0.025] as an independent risk factor for AL. CONCLUSIONS: Male sex and a history of IHD are possible risk factors for AL after elective laparoscopic rectal cancer surgery.

[Obstructive Colon Cancer with Triple-Vessel Coronary Artery Disease - A Case Report].

The patient was a 70-year-old woman who was diagnosed with obstructive transverse colon cancer suspected of invading the abdominal wall by abdominal CT imaging. Since the preoperative electrocardiogram showed an ischemic change, echocardiography and coronary angiography were performed. We diagnosed chronic heart failure and angina pectoris because echocardiography showed low cardiac function(left ventricular ejection fraction; LVEF 37%)and coronary angiography indicated triple-vessel disease. We firstly performed coronary artery bypass graft surgery following self-expanding metallic stent placement as a bridge to surgery(BTS), because we judged this patient as a perioperative high-risk case. After improvement of cardiac function(LVEF 49%), expanded right hemicolectomy with partial resection of abdominal wall could be performed without perioperative complications. Colonic stenting as a BTS allowed us to treat comorbidities properly, and perform a radical surgery safely for such a high-risk patient.

A Rapidly Growing Small-Intestinal Metastasis from Lung Cancer.

Small-intestinal metastasis from lung cancer, although relatively rare, often causes intestinal obstruction, gastrointestinal perforation, and gastrointestinal bleeding, making it an oncological emergency. Many patients have undergone emergency surgery for treatment of rapid progression of an intestinal metastatic lesion; however, information on changes in such metastases is lacking. We analyzed data from 4 patients with small-intestinal metastases from lung cancer who were treated during a 10-year period (January 2011 to December 2020) and for whom data on change in tumor diameter were available. The average rate of growth in tumor volume was 1.48-fold (range, 1.31- to 1.78-fold) during a median observation period of 22 (4-39) days, a rapid increase. Histopathological analysis showed that, in patients with a high degree of primary tumor atypia, rapid tumor growth may be caused by intratumoral hemorrhage, which was the reason for the rapid increase in tumor volume.

Development of transomental hernia shortly after laparoscopic colonic surgery: a case report.

BACKGROUND: A transomental hernia is defined as bowel invagination into an abnormal hiatus of the omentum. It is a rare type of internal hernia that is sometimes lethal. We herein report a case of a transomental hernia developing shortly after laparoscopic sigmoidectomy. CASE PRESENTATION: A 71-year-old man underwent laparoscopic sigmoidectomy. He was admitted to our hospital because of abdominal pain and nausea on postoperative day 12. Laboratory investigation showed increased levels of inflammatory markers. Abdominal computed tomography showed a closed loop and mesenteric edema of the small intestine with ascites. We performed an emergency operation under the diagnosis of strangulated bowel obstruction. Operative findings showed internal herniation of strangulated ileal loops through a defect of the omentum with hemorrhagic ascites. The incarcerated small bowel was resected and reconstructed because the ischemic change was irreversible after the reduction. We partially resected the omentum that had formed the defect. The patient's postoperative progress was good, and he was discharged on postoperative day 8. CONCLUSIONS: Almost all internal hernias after intestinal surgery are mesenteric hernias; however, we should bear in mind that the more lethal transomental hernia is also possible. Therefore, immediate surgical exploration should be performed in a timely manner for internal hernias, especially for patients with early-onset symptoms after laparoscopic intestinal surgery.

Successful management of duodenal varices by balloon-occluded retrograde transvenous obliteration.

We describe a case of duodenal varices successfully treated with balloon-occluded retrograde transvenous obliteration (BRTO) alone. A 63-year-old man presented with tarry stools. Computed tomography demonstrated dilated varices around the duodenum. Emergency endoscopic examination revealed varices of the second portion of the duodenum without active bleeding. There was no evidence of bleeding in the esophagus or stomach. Colonoscopy revealed no bleeding sites in the colon. On the day after admission, a superior mesenteric arteriogram obtained in the venous phase demonstrated a collateral vein from the inferior pancreaticoduodenal vein to the inferior vena cava. Retrograde venography performed via the right femoral vein confirmed that the right inferior adrenal vein was the draining vein and that the collateral vein was occluded. There were no tarry stools after BRTO. The patient was discharged 7 days after BRTO. Two months after discharge, computed tomography showed no dilated varices around the duodenum. Three months after discharge, endoscopy confirmed the absence of varices. No bleeding has been detected as of 10 months after discharge. We conclude that BRTO is an effective treatment for duodenal varices.

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.

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.

Stomach arteriovenous malformation resected by laparoscopy-assisted surgery: A case report.

Arteriovenous malformations of the stomach are an uncommon cause of upper GI bleeding. We report a case of stomach arteriovenous malformation in an 85-year-old Asian man who presented with massive hematemesis. Initial esophagogastroduodenoscopy did not detect this lesion, but contrast multi-detector CT confirmed GI bleeding. Multi-detector CT revealed a mass of blood vessels underlying the submucosa that arose from the right gastroepiploic artery. Repeat esophagogastroduodenoscopy showed that the lesion was a submucosal tumor with erosion and without active bleeding in the lower body of the stomach on the greater curvature. We performed partial gastrectomy via laparoscopy-assisted surgery. The histopathological diagnosis was arteriovenous malformation.

Histopathological study of tissue reaction to pacemaker electrodes implanted in the endocardium.

Limited information is available about histopathological reactions to the implanted endocardial electrodes of pacemakers (PM). Gross anatomic and histologic studies of tissue reactions to PM electrodes were made in thirteen autopsy cases (nine men and four women, ages 25 approximately 89 years, mean age 71.8) who died two months to twenty-one years after PM implantation. Nine of them had complete atrioventricular (AV) block, three had sick sinus syndrome, and one had bradycardia-tachycardia syndrome. The direct causes of death were not related to their PM. The tip with projecting tines was implanted in the right ventricle in all patients. At the contact area between the electrode and the endocardium, no tissue reaction was observed in one patient with a history of over sixteen years of PM implantation. However, cardiomyocytes under the tip had been replaced by fibrotic tissue in many other patients. In two patients in particular where the electrode had been implanted at the apex of each right ventricle, all cardiomyocytes had disappeared and only fibrotic tissue and adipose tissue were observed under the tip. These findings suggest that mechanical stress caused by attaching the tip tightly damages cardiomyocytes and brings about changes in the pacing thresholds. In three patients, a space was seen between the tip and the endocardium. A fibrous sheath covering the electrode extended to the tip and formed a thick fibrous cap. This non-excitable fibrous cap acted as a virtual electrode and possibly affected the elevation of the threshold in these patients. In four patients, extensive myocardial fibrosis due to disease, e. g. previous myocardial infarction, dilated cardiomyopathy, amyloidosis, or sarcoidosis, was found in the area surrounding the tip and also might affect the elevation of the threshold. We concluded that elevation of pacing thresholds after PM implantation is not due to reactive endocardial thickening. The space between the tip and the endocardium is occupied by a fibrous sheath, and an overly tight attachment damages cardiomyocytes causing replacement fibrosis. Thus, it is not desirable in some patients to insert the electrodes into the apex, where the myocardium is thin. To avoid the elevation of thresholds, development of further devices is necessary to allow electrode fixation to the endocardium with a more suitable pressure level.

Spontaneous rupture of a simple hepatic cyst: report of a case.

We describe the spontaneous rupture of a simple hepatic cyst. A 62-year-old woman was admitted for right upper quadrant pain of sudden onset. The patient denied a history of abdominal trauma. Computed tomography of the abdomen showed a 13-cm-diameter solitary hepatic cyst in the right lobe. Part of the cyst surface was irregular, and the internal echo was heterogeneous. Retained fluid was detected under the liver capsule. Ten days after admission, computed tomography revealed that the volume of fluid retained under the liver capsule had decreased but that the hepatic cyst had enlarged again. The patient was referred to our hospital for further evaluation and treatment. Physical examination revealed mild right upper quadrant pain, but no signs or symptoms of peritonitis or abnormalities of the chest or heart. Percutaneous puncture was performed with a needle and an 8-French pigtail catheter under ultrasonographic guidance. Brown serous fluid was aspirated. After the removal of approximately 1,000 mL of fluid, contrast medium was injected to check for communications between the cyst and the biliary tree and to document the absence of leakage into the peritoneal cavity. After complete aspiration of the cyst fluid, 200 mg of minocycline hydrochloride dissolved in 10 mL of saline was injected into the cyst, and the catheter was flushed with 10 mL of saline (total volume of saline, 20 mL). The catheter was then clamped for 30 minutes. After percutaneous aspiration, the patient's symptoms resolved. Minocycline hydrochloride was injected daily for 7 days, and the catheter was removed. There has been no evidence of recurrence after 2 years.

Strong local passivity in finite quantum systems.

Passive states of quantum systems are states from which no system energy can be extracted by any cyclic (unitary) process. Gibbs states of all temperatures are passive. Strong local (SL) passive states are defined to allow any general quantum operation, but the operation is required to be local, being applied only to a specific subsystem. Any mixture of eigenstates in a system-dependent neighborhood of a nondegenerate entangled ground state is found to be SL passive. In particular, Gibbs states are SL passive with respect to a subsystem only at or below a critical system-dependent temperature. SL passivity is associated in many-body systems with the presence of ground state entanglement in a way suggestive of collective quantum phenomena such as quantum phase transitions, superconductivity, and the quantum Hall effect. The presence of SL passivity is detailed for some simple spin systems where it is found that SL passivity is neither confined to systems of only a few particles nor limited to the near vicinity of the ground state.