Implicit Motor Learning Strategies Benefit Dual-Task Performance in Patients with Stroke.

Background and Objectives: In stroke rehabilitation, the use of either implicit or explicit learning as a motor learning approach during dual tasks is common, but it is unclear which strategy is more beneficial. This study aims to determine the benefits of implicit versus explicit motor learning approaches in patients with stroke. Materials and Methods: Seventeen patients with stroke and 21 control participants were included. Motor learning was evaluated using the Serial Reaction Time Task (SRTT) in the context of dual-task conditions. The SRTT was conducted on two separate days: one day for implicit learning conditions and the other day for explicit learning conditions. Under the explicit learning conditions, a task rule was given to the participants before they started the task, but not under the implicit learning conditions. Learning scores were calculated for both implicit and explicit learning, and these scores were then compared within groups for patients with stroke and controls. We calculated the difference in learning scores between implicit and explicit learning and conducted a correlation analysis with the Trail Making Test (TMT) Parts A and B. Results: Learning scores on the SRTT were not different between implicit and explicit learning in controls but were significantly greater in patients with stroke for implicit learning than for explicit learning. The difference in learning scores between implicit and explicit learning in patients with stroke was correlated with TMT-A and showed a correlation trend with TMT-B. Conclusions: Implicit learning approaches may be effective in the acquisition of motor skills with dual-task demands in post-stroke patients with deficits in attention and working memory.

Efficacy of chemotherapy for comorbid cancer in patients with simultaneous double cancers: a multicenter study.

PURPOSE: Anticancer drugs for double cancers are selected based on their therapeutic effects on the target cancer, but there are insufficient data on the effects of anticancer drugs on comorbid cancer. We investigated the effect of chemotherapy on comorbid cancer in patients with simultaneous double cancers. METHODS: The subjects of this retrospective study were 51 patients with simultaneous double cancers at the time of receiving systemic chemotherapy. We evaluated the types of anticancer drugs used for double cancers, the therapeutic effects on targeted and comorbid cancers, and prognoses. RESULTS: Disease control was achieved for 90.9% of the target cancers and 90.7% of the comorbid cancers. The prognosis was significantly better when the disease was controlled, not only in the target cancer but also in the comorbid cancer. CONCLUSION: Physicians treating double cancers should develop treatment strategies focusing not only on the treatment for advanced cancer, but also on the course of comorbidities and the therapeutic effects of anticancer drugs. This study is important because it presents new possibilities to expand the indications for anticancer drugs, while allowing unnecessary clinical research to be avoided.

Cathepsin G-induced malignant progression of MCF-7 cells involves suppression of PAF signaling through induced expression of PAFAH1B2.

Breast cancer is primarily classified into ductal and lobular types, as well as into noninvasive and invasive cancer. Invasive cancer involves lymphatic and hematogenous metastasis. In breast cancer patients with distant metastases, a neutrophil-derived serine protease; cathepsin G (Cat G), is highly expressed in breast cancer cells. Cat G induces cell migration and multicellular aggregation of MCF-7 human breast cancer cells; however, the mechanism is not clear. Recently, platelet-activating factor (PAF)-acetylhydrolase (PAF-AH), the enzyme responsible for PAF degradation, was reported to be overexpressed in some tumor types, including pancreatic and breast cancers. In this study, we investigated whether PAF-AH is involved in Cat G-induced aggregation and migration of MCF-7 cells. We first showed that Cat G increased PAF-AH activity and elevated PAFAH1B2 expression in MCF-7 cells. The elevated expression of PAFAH1B2 was also observed in human breast cancer tissue specimens by immunohistochemical analysis. Furthermore, knockdown of PAFAH1B2 in MCF-7 cells suppressed the cell migration and aggregation induced by low concentrations, but not high concentrations, of Cat G. Carbamoyl PAF (cPAF), a nonhydrolyzable PAF analog, completely suppressed Cat G-induced migration of MCF-7 cells. In addition, PAF receptor (PAFR) inhibition induced cell migration of MCF-7 cells even in the absence of Cat G, suggesting that Cat G suppresses the activation of PAFR through enhanced PAF degradation due to elevated expression of PAFAH1B2 and thereby induces malignant phenotypes in MCF-7 cells. Our findings may lead to a novel therapeutic modality for treating breast cancer by modulating the activity of Cat G/PAF signaling.

Malignant perivascular epithelioid cell neoplasm in the liver: report of a pediatric case.

BACKGROUND: Perivascular epithelioid cell neoplasm (PEComa) in a child is very rare. We herein report the first malignant case of PEComa developing in the liver of a pediatric patient. CASE PRESENTATION: A 10-year-old boy visited a private clinic with prolonged fever of unknown etiology. Abdominal ultrasonography was performed to evaluate the fever's origin, revealing a large tumor in the liver. He was thus referred to a nearby hospital to investigate the tumor further. Enhanced computed tomography (CT) showed a 6.8 × 5.9 × 10.5-cm solid lesion on S4 and S5. On magnetic resonance imaging (MRI), the tumor had a low signal intensity on T1 imaging and high signal intensity on T2 imaging, with partial diffusion restriction. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed a marked uptake in the mass lesion with no evidence of metastasis. The patient was negative for all tumor markers, including AFP, CEA and PIVKA-II. The results of a needle biopsy suggested hepatocellular carcinoma. The tumor's rapid growth suggested malignancy. Hepatic segmentectomy (S4 + S5 + S8) was performed. The tumor was resected en bloc with a margin. Microscopically, the tumor showed atypical spindle, polygonal or oval-shaped cells with a high nuclear grade, and vascular invasion. Immunohistochemistry was positive for alpha-smooth muscle antigen (α-SMA), human melanin black-45 (HMB-45) and melan A. The pathological diagnosis was malignant PEComa. In the 6 months after surgery, the patient complained of shoulder pain. MRI showed a dumbbell-shaped tumor at the 2nd thoracic vertebrae, which was confirmed to be bone metastasis of PEComa. After chemotherapy, including ifosfamide and doxorubicin, vertebrectomy was performed. Two years later, thoracoabdominal CT showed a 10-cm solid mass occupying the pelvis and a 15-mm nodule in the middle lobe of the right lung. Under a diagnosis of peritoneal and lung metastases, they were surgically removed and metastasis of PEComa was pathologically confirmed. Four months after the 2nd relapse, pelvic metastasis appeared again and mTOR (mammalian target of rapamycin) inhibitor was initiated. To our knowledge, this is the first report of malignant hepatic PEComa in a pediatric patient. CONCLUSION: Although extremely rare, malignant hepatic PEComa can develop in a child.

Colorectal Cancer Patients Have Four Specific Bacterial Species in Oral and Gut Microbiota in Common-A Metagenomic Comparison with Healthy Subjects.

Oral microbiota is reportedly associated with gut microbiota and influences colorectal cancer (CRC) progression; however, the details remain unclear. This study aimed to evaluate the role of oral microbiota in CRC progression. Fifty-two patients with CRC and 51 healthy controls were included. Saliva and stool samples were collected, and microbiota were evaluated using 16S rRNA analysis and next-generation sequencing. Comparative analysis was performed on both groups. Linear discriminant analysis effect size (LEfSe) revealed the presence of indigenous oral bacteria, such as Peptostreptococcus, Streptococcus, and Solobacterium spp., at a significantly higher relative abundance in saliva and stool samples of CRC patients compared with controls. Next, CRC patients were divided into early stage (Stage I, II; n = 26; 50%) and advanced stage (Stage III, IV; n = 26; 50%) disease. LEfSe revealed that S. moorei was present at a significantly higher relative abundance in the advanced-stage group compared with the early-stage group, again consistent for both saliva and stool samples. Among bacterial species with significantly higher relative abundance in CRC patients, P. stomatis, S. anginosus, S. koreensis, and S. moorei originated from the oral cavity, suggesting indigenous oral bacteria may have promoted initiation of CRC carcinogenesis. Furthermore, S. moorei may influence CRC progression.

Immediate breast reconstruction with expander following recurrent lesion resection and exchange to silicon breast implant in a pregnant triple negative breast cancer patient: case report.

A 39-year-old gravida 1 para 1 pregnant Japanese woman underwent skin-sparing mastectomy and axillary lymph node dissection with immediate breast reconstruction (IBR) using a tissue expander (TE) at 32 weeks of pregnancy under general anesthesia. Inserted TE (300 cc) was expanded during breast feeding while the volume was 240 cc of the resected breast tissue. One month after delivery, 2 months after surgery, the contralateral healthy breast increased in size and the inframammary line was deviated toward a caudal site which was larger than 300 cc-inflated TE. She stopped breast feeding to receive a systemic chemotherapy after one months-breast feeding. At 3 months after delivery, the healthy breast size was smaller than the 250 cc-expanded breast and both the inframammary lines were at the same level. She was diagnosed local recurrence 3 month-postoperatively, so we resected the recurrent lesion and exchanged TE to silicon breast implant immediately. Finally, a good symmetry was obtained after insertion of the 220 cc SBI. At an IBR using TE, we should know the dynamic change of breast volume and the level of inframammary line of the healthy breast during those phases of pregnancy, delivery, and nursing.

Mutant p53 regulates Survivin to foster lung metastasis.

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal cancers worldwide and evolves often to lung metastasis. P53R175H (homologous to Trp53R172H in mice) is a common hot spot mutation. How metastasis is regulated by p53R175H in ESCC remains to be investigated. To investigate p53R175H-mediated molecular mechanisms, we used a carcinogen-induced approach in Trp53R172H/- mice to model ESCC. In the primary Trp53R172H/- tumor cell lines, we depleted Trp53R172H (shTrp53) and observed a marked reduction in cell invasion in vitro and lung metastasis burden in a tail-vein injection model in comparing isogenic cells (shCtrl). Furthermore, we performed bulk RNA-seq to compare gene expression profiles of metastatic and primary shCtrl and shTrp53 cells. We identified the YAP-BIRC5 axis as a potential mediator of Trp53R172H -mediated metastasis. We demonstrate that expression of Survivin, an antiapoptotic protein encoded by BIRC5, increases in the presence of Trp53R172H Furthermore, depletion of Survivin specifically decreases Trp53R172H-driven lung metastasis. Mechanistically, Trp53R172H but not wild-type Trp53, binds with YAP in ESCC cells, suggesting their cooperation to induce Survivin expression. Furthermore, Survivin high expression level is associated with increased metastasis in several GI cancers. Taken together, this study unravels new insights into how mutant p53 mediates metastasis.

Clinical significance of circulating tumor cells in the response to trastuzumab for HER2-negative metastatic gastric cancer.

PURPOSE: The prognosis of metastatic gastric cancer has improved due to trastuzumab in patients with HER2 positive. Circulating tumor cells (CTCs) have been examined as a prognostic predictor in gastric cancer. The clinical advantage of trastuzumab was examined in gastric cancer patients with HER2-negative tumor tissues and HER2-positive CTCs. METHODS: A total of 105 patients with metastatic or recurrence gastric cancer were enrolled. All patients were examined HER2 expression in CTC using the CellSearch system in blood specimens. RESULTS: CTCs were detected in 65 of 105 patients (61.9%) and 61 patients were divided into three groups: Group A (n = 27), histological HER2-positive; Group B (n = 17), histological HER2-negative and HER2-positive CTCs; and Group C (n = 17), HER2-negative on histology and CTCs. Patients received capecitabine plus cisplatin. Groups A and B were additionally treated by trastuzumab. There was no relationship between tumor tissues and CTCs in HER2 expression. Even if group B had no histological HER2 expression, group B showed a good prognosis as same as group A, and group C had a significantly worse overall survival than groups A and B. The multivariate analysis demonstrated that HER2-expression on CTCs was an independent prognostic factor for both overall and progression-free survival. CONCLUSION: The present results indicate the potential clinical utility of trastuzumab combined chemotherapy in patients with HER2-positive CTCs even if they are histologically HER2-negative.

Successful treatment of post chemotherapy esophageal cicatricial atresia in a pediatric patient with anaplastic large cell lymphoma through minimally invasive esophagectomy: a case report.

BACKGROUND: Anaplastic large cell lymphoma (ALCL) is a CD30-positive T-cell lymphoma, which is a rare type of non-Hodgkin lymphoma. ALCL rarely presents in the gastrointestinal tract, and the esophageal involvement in of ALCL is extremely rare. CASE PRESENTATION: An 11-year-old boy who complained of abdominal pain and cough was diagnosed with ALK-positive ALCL on the basis of systemic lymphadenopathy findings and immunohistochemistry results of pleural effusion. Although remission was observed after chemotherapy at 5 months after diagnosis, dysphagia persisted, and esophagoscopy revealed a severe stricture in the middle thoracic esophagus. At 9 months after diagnosis, allogeneic bone marrow transplantation was performed to ensure that complete remission was maintained; however, dysphagia and saliva retention did not improve. Approximately 10 months after diagnosis, esophagoscopy revealed a blind end in the middle thoracic esophagus, similar to that in congenital esophageal atresia. Subsequently, we performed minimally invasive subtotal esophagectomy under thoracoscopy and laparoscopy and gastric conduit reconstruction via the retrosternal route more than 2 years after allogeneic bone marrow transplantation. The final pathological diagnosis was esophageal atresia with esophagitis, with no malignancy. During postoperative evaluation, the patient required swallowing training for a few months, although no major complications were noted. Oral intake was possible, and complete remission was maintained at 14 month post-surgery. CONCLUSIONS: Oncologists must consider the possibility of acquired esophageal cicatricial atresia as a complication during chemotherapy for ALCL. If esophageal obstruction or esophageal atresia occur and if remission is maintained, esophagectomy and esophageal reconstruction are useful treatment options for maintaining oral intake.

[A Case of an Elderly Frail Patient with Unresectable Colorectal Cancer Controlled by Trifluridine/Tipiracil with Bevacizumab Therapy as a First-Line Treatment].

Although the effectiveness of trifluridine/tipiracil(TFTD)with bevacizumab for unresectable colorectal cancer that was refractory to previous standard chemotherapy was reported, its effectiveness as a first-line treatment, especially for elderly frail patients, is unclear. An 85-year-old woman complaining of anorexia was diagnosed with unresectable sigmoid colon cancer with multiple metastases. Her general status was very poor, and her performance status(PS)was 4. We first performed laparoscopic transverse colostomy. As her general status gradually improved, we administered TFTD with bevacizumab as a first-line treatment based on the patient's strong request for chemotherapy. The patient underwent this regimen in the outpatient clinic for 9 months(9 courses). Although the size of the liver metastases increased, lung metastases and abdominal disseminations were under control and her PS became 0. She has been taking mFOLFOX6 with bevacizumab (80%)as a second-line treatment. TFTD with bevacizumab treatment was safe and efficacious as a first-line treatment for a frail elderly patient with unresectable colorectal cancer.

Modified Delta-shaped Anastomosis via the Overlap Method Using Linear Staplers for Colon Cancer.

Here, we describe the modified delta-shaped anastomosis (DSA) via the overlap method and how it was a beneficial intracorporeal anastomotic technique for four patients who underwent laparoscopic colectomy. After resecting the colon on both sides of the lesion, proximal and distal colon were laid in an overlap fashion and fixed using sutures. The entry hole was created using an ultrasound scalpel at a point 3 cm proximal to right colic stump and 7 cm distal to left colic stump on the anti-mesenteric side. Then, two arms of the linear stapler were inserted inside each lumen and fired. Finally, using the linear stapler, the common entry hole was closed in a delta-shaped manner. The mean duration of surgery was determined to be 218.4 (196-369) minutes, and amount of blood loss was measured to be 11 (5-25) mL. No intraoperative and postoperative complications were observed. Median postoperative hospital stay was 12 days. Thus, modified DSA via overlap method can be considered as a safe and simple IA technique.

Locally advanced cholangiolocellular carcinoma successfully treated with curative resection after downsizing chemotherapy: a case report.

BACKGROUND: Cholangiolocellular carcinoma (CoCC) is an extremely rare disease comprising less than 1% of all primary malignant liver tumors. No effective treatment other than resection has been established. Herein, we report a case of locally advanced CoCC diagnosed as unresectable, which was successfully treated with curative resection after downsizing chemotherapy. CASE PRESENTATION: A 59-year-old Japanese woman with chronic hepatitis B was diagnosed with locally advanced intrahepatic cholangiocellular carcinoma. As it was difficult to perform R0 resection in the local hospital, chemotherapy combined with gemcitabine plus cisplatin was administered every 3 weeks. After a total of 10 courses of chemotherapy over 10 months the tumor was shown to be reduced in size by computed tomography imaging, and she was referred to our department for surgical resection. The effect of chemotherapy was classified as a "partial response" in the response evaluation criteria of solid tumors. After adding one course of chemotherapy, an extended left hepatectomy with resection of the caudate lobe was performed. R0 resection was achieved. Based on the pathological findings, the final diagnosis of CoCC was determined and eight courses of S-1 adjuvant chemotherapy were administered. At 14 months after the operation, the patient was alive without tumor recurrence. CONCLUSIONS: Downsizing chemotherapy with gemcitabine and cisplatin may be an effective treatment strategy in locally advanced CoCC. Further evidence is required to establish an optimal strategy for the treatment of locally advanced CoCC.

Clinical impact of creatine phosphokinase and c-reactive protein as predictors of postgastrectomy complications in patients with gastric cancer.

BACKGROUND: Postoperative complications have been linked to the morbidity and mortality of several cancers. However, predicting whether complications will occur in the early period after surgery or not is challenging. Hence, this study aimed to examine the diagnostic accuracy of serum creatine phosphokinase (CPK) and c-reactive protein (CRP) in predicting the development of postgastrectomy complications. METHODS: We retrospectively analyzed 188 patients with gastric cancer (GC) who underwent gastrectomy. The diagnostic accuracy of serum CPK and CRP was investigated using the areas under the curves (AUC). The CPK ratio was defined as the CPK on postoperative day (POD) 1 to the CPK on a preoperative day. RESULTS: Out of 188 patients, 48 (25.5%) developed postoperative complications. The complications group had a greater operative time (p = 0.037), higher CPK ratio on POD1 (p < 0.0001), and a higher serum CRP level on POD3 (p = 0.001). The AUC for the CPK ratio was 0.772, with an optimal cutoff value of 7.05, whereas that for CRP was 0.659, with an optimal cutoff value of 11.4 mg/L. The CPK ratio on POD1 (p < 0.0001) and the CRP on POD3 (p = 0.007) were independent factors for predicting the development of postgastrectomy complications. The CPK ratio on POD1 and the CRP on POD3 predicted postgastrectomy complications in 41 patients (85.4%). According to combined value of both CPK ratio and CRP level, the positive predictive value and the negative predictive value was 0.70 and 0.829. And sensitivity and specificity were 0.438 and 0.936. CONCLUSION: The CPK ratio on POD1 and the CRP on POD3 after gastrectomy for GC were predictive factors for complication development and may be employed to prevent the development of such complications and improve the prognosis of patients with GC.

Clinical Outcomes of Fully Covered Self-expanding Metallic Stent Placement for Palliation of Incurable Esophageal Cancer With or Without Radiotherapy.

BACKGROUND/AIM: A combination therapy of esophageal stent and chemoradiotherapy (CRT) is currently considered risky for severe complications. The aim of this study was to assess the safety and efficacy of a fully covered self-expandable metallic stent (FCSEMS) placement in palliating incurable esophageal cancer before and/or after CRT. PATIENTS AND METHODS: We retrospectively reviewed clinical outcomes of 64 incurable advanced esophageal cancer patients with FCSEMS placement. Forty-two of 64 patients had FCSEMS placement with RT. RESULTS: The rate of all of stent-related complications tended to be higher in patients who had RT, although no significant difference was observed. The stent-related deaths occurred in one patient due to hemorrhage after FCSEMS placement in the RT-negative group. CONCLUSION: Palliation of dysphagia or fistulas with FCSEMS in patients with incurable esophageal cancer before and/or after RT is not associated with an increased risk of life-threatening complications.

A multicenter non-randomized phase III study of sentinel node navigation surgery for early gastric cancer.

This prospective multicenter non-randomized phase III study aims to evaluate the long-term outcome of sentinel node navigation surgery for early gastric cancer compared with conventional distal or total gastrectomy. Clinically diagnosed primary T1N0M0 gastric cancer patients with a single lesion (≤40 mm) and without previous endoscopic treatment will be enrolled in this study. Sentinel nodes are identified by dye and radioisotope tracers and are subjected to intraoperative rapid pathology. For patients with negative sentinel node metastasis, individualized surgery consisting of limited stomach resection and sentinel node basin dissection is performed, while standard gastrectomy with D2 lymph node dissection is employed for the positive sentinel node patients. A total of 225 patients will be accrued from 13 hospitals that have experience in sentinel node mapping. The primary endpoint is 5-year relapse-free survival. The secondary endpoints are overall survival, sentinel node detection rate, diagnostic accuracy for sentinel node, distribution of sentinel nodes and metastatic sentinel node/non-sentinel node, and postoperative quality of life.

Comparison of greater curvature and lesser curvature circular-stapled esophagogastrostomy after esophagectomy in patients with esophageal cancer: a prospective randomized controlled trial.

PURPOSE: Using a circular stapler to create an anastomosis for esophagogastrostomy after esophagectomy is well accepted; however, it remains uncertain if the greater curvature (GC) or lesser curvature (LC) of the gastric conduit is better for the anastomosis. We conducted this prospective study to compare the integrity of esophagogastrostomy between the esophagus and the GC or LC side of the gastric conduit. METHODS: The subjects of this study were 70 patients who underwent esophagectomy and were randomized to a "GC" group and an "LC" group (n = 35 each). The primary and secondary end points were anastomotic leakage (AL) and anastomotic stricture (AS), respectively. RESULTS: The overall AL rate was 22.1%, without a significant difference between the groups. Stump leakage developed in eight of nine patients in the GC group, whereas leakage developed at the esophagogastric anastomosis in five of six patients in the LC group. The rate of stump leakage was significantly higher than that of esophagogastric AL in the GC group. The overall AS rate was 4.4%, with a significant difference between the groups (0% in the GC group vs. 9.1% in the LC group). CONCLUSIONS: AL rates were comparable in the two groups, but the sites of leakage were significantly different.

The 1-year outcomes after pancreaticogastrostomy using vertical versus horizontal mattress suturing for gastric wrapping.

PURPOSE: To investigate the differences in nutritional status 1 year after pancreaticogastrostomy (PG) using vertical suturing (VS) vs. twin square horizontal mattress (HMS) suturing in patients undergoing pancreaticoduodenectomy (PD). METHODS: The subjects of this study were 134 patients who underwent PD, followed by PG, which was closed by VS in 52 and by HMS in 82. We evaluated the peri- and postoperative factors, nutritional parameters, diameter of the remnant main pancreatic duct, and glucose intolerance 1 year postoperatively. RESULTS: Forty-five (87%) patients from the VS group and 75 (91%) patients from the HMS group survived for more than 1 year. The incidences of intraabdominal abscess and pancreatic fistula were significantly lower in the HMS group than in the VS group (19.2% vs. 6.6% and19.2% vs. 2.6%, respectively). There were no significant changes in the total protein, serum albumin, and HbA1c levels 1 year postoperatively. The postoperative expansion ratio of the main pancreatic duct diameter was significantly smaller in the HMS group than in the VS group. The strongest risk factor for body weight loss 1 year postoperatively was a non-soft pancreas texture. CONCLUSION: HMS was superior to VS for preventing early postoperative complications and did not affect pancreatic function.

Usefulness of 18F-fluorodeoxyglucose-positron emission tomography/computed tomography in primary cystadenocarcinoma of the mesentery: a case report.

BACKGROUND: Mesenteric cysts have various histological forms, including mesenteric cystadenomas and borderline cystic neoplasms. Primary cystadenocarcinoma of the mesentery is extremely rare; therefore, the clinical and radiological features of this tumor have not been fully elucidated. CASE PRESENTATION: A 50-year-old Japanese woman had a complaint of a left-sided abdominal distention. Enhanced computed tomography and magnetic resonance imaging revealed a unilocular cystic lesion measuring approximately 10 cm located in the left side of the abdomen. 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) revealed mottled mild FDG uptake in the cyst wall and intense FDG uptake in several mural nodules. The cystic mass with the descending colon was completely removed. Pathological examination of the specimens revealed various histologic patterns of adenocarcinoma, including mucin production in the mural nodules. We eventually diagnosed a primary cystadenocarcinoma arising from the mesentery of the descending colon. CONCLUSIONS: Malignancy should be suspected in mesenteric or retroperitoneal cystic tumors with high FDG uptake, and complete resection should be performed with adequate margins.

The Diagnostic and Prognostic Value of a Liquid Biopsy for Esophageal Cancer: A Systematic Review and Meta-Analysis.

Esophageal cancer is among the most aggressive diseases, and circulating tumor cells (CTCs) have been recognized as novel biomarkers for various cancers over the past two decades, including esophageal cancer. CTCs might provide crucial clinical information for predicting cancer prognosis, monitoring therapeutic responses or recurrences, or elucidating the mechanism of metastasis. The isolation of CTCs is among the applications of a "liquid biopsy". There are various technologies for liquid biopsies, and they are classified into two main methods: cytometric or non-cytometric techniques. Here, we review a total of 57 eligible articles to summarize various technologies for the use of a liquid biopsy in esophageal cancer and perform a meta-analysis to assess the clinical utility of liquid biopsies as a prognostic and diagnostic biomarker technique. For prognostic evaluation, the pooled hazard ratio in the cytometric assay is relatively higher than that of the non-cytometric assay. On the other hand, a combination of multiple molecules, using a non-cytometric assay, might be a favorable biomarker technique for the early diagnosis of esophageal cancer. Although determining strong evidence for a biomarker by using a liquid biopsy is still challenging, our meta-analysis might be a milestone for the future development of liquid biopsies in use with esophageal cancer.