How Does Omitting Additional Surgery After Local Excision Affect the Prognostic Outcome of Patients With High-risk T1 Colorectal Cancer?

OBJECTIVE: To investigate how omitting additional surgery after local excision (LE) affects patient outcomes in high-risk T1 colorectal cancer (CRC). BACKGROUND: It is debatable whether additional surgery should be performed for all patients with high-risk T1 CRC regardless of the tolerability of invasive procedures. METHODS: Patients who had received LE for T1 CRC at the Japanese Society for Cancer of the Colon and Rectum institutions between 2009 and 2016 were analyzed. Those who had received additional surgical resection and those who did not were matched one-on-one by the propensity score-matching method. A total of 401 propensity score-matched pairs were extracted from 1975 patients at 27 Japanese Society for Cancer of the Colon and Rectum institutions and were compared. RESULTS: Regional lymph node metastasis was observed in 31 (7.7%) patients in the LE + surgery group. Comparatively, the incidence of oncologic adverse events was low in the LE-alone group, such as the 5-year cumulative risk of local recurrence (4.1%) or overall recurrence (5.5%). In addition, the difference in the 5-year cancer-specific survival between the LE + surgery and LE-alone groups was only 1.8% (99.7% and 97.9%, respectively), whereas the 5-year overall survival was significantly lower in the LE-alone group than in the LE + surgery group [88.5% vs 94.5%, respectively ( P = 0.002)]. CONCLUSIONS: Those who had decided to omit additional surgery at the dedicated center for CRC treatment presented a small number of oncologic events and a satisfactory cancer-specific survival, which may suggest an important role of risk assessment regarding nononcologic adverse events to achieve a best practice for each individual with high-risk T1 tumors.

Ruptured breast implant removal because of patient anxiety in the absence of breast implant-associated anaplastic large cell lymphoma.

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) has been regarded as a long-term problem after silicone breast implantations. We report a case in which BIA-ALCL and breast cancer were not detected preoperatively, with subsequent removal of a ruptured breast implant. A 52-year-old woman had silicone breast implants on both sides for breast augmentation 15 years ago. Right axillary lymphadenopathy and intracapsular ruptures were noted by magnetic resonance imaging. Right axillary lymph node biopsy was performed at our department of breast surgery. Flow cytometry for BIA-ALCL was also performed using the exudate around the implant. The results were negative for breast cancer and BIA-ALCL. However, taking into consideration exacerbation of breast implant rupture and the patient's anxiety about BIA-ALCL, ruptured bilateral implants were removed by total capsulectomy. The postoperative course was uneventful 1 year after the operation, and her anxiety was dispelled despite her breast deformity. Appropriate explantation and periodic examination may be required to prevent excessive anxiety.

＜Editors' Choice＞ Long-term outcomes of lateral skull base reconstruction with a free omental flap and facial nerve reconstruction.

In lateral skull base reconstruction, it is necessary to seal the defect in the lateral skull base, fill the dead space, and, sometimes, reconstruct the facial nerve. However, this procedure is difficult to perform with a standard musculocutaneous flap. Therefore, for such cases, an omental flap is used in our hospital because of its flexibility. In this study, we report our experience with the procedure (lateral skull base reconstruction with a free omental flap) and its long-term outcome and facial nerve reconstruction, with special focus on facial nerve recovery. This study is a technical note and a retrospective review. It was conducted in Nagoya University Hospital. Overall, 16 patients (12 women and 4 men; mean age: 55.1 years) underwent lateral skull base reconstruction with a free omental flap after subtotal temporal bone resection or lateral temporal bone resection during 2005-2017. The main outcome measures were postoperative complications and facial nerve recovery: Yanagihara score and House-Brackmann grading system. Complications included partial necrosis and minor cerebrospinal fluid leakage in 2 patients. Facial nerve recovery could be observed more than 12 months after surgery, with a mean Yanagihara score of 19.6 and House-Brackmann grade of 3.60. The free omental flap is a reliable method for lateral skull base reconstruction, especially in cases where facial nerve reconstruction is needed. To the best of our knowledge, this is the first report on facial nerve recovery after lateral skull base reconstruction.

MicroRNAs associated with postoperative outcomes in patients with limited stage neuroendocrine carcinoma of the esophagus.

Esophageal neuroendocrine carcinoma (E-NEC) is an aggressive disease with a poor prognosis. The present study aimed to assess the role of surgery in the treatment of patients with resectable E-NEC, and identify a microRNA (miRNA/miR) signature in association with positive postoperative outcomes. Between February 2017 and August 2019, 36 patients with E-NEC who underwent curative surgery at the Japan Neuroendocrine Tumor Society partner hospitals were enrolled in the study. A total of 16 (44.4%) patients achieved disease-free survival (non-relapse group), whereas 20 (55.6%) patients developed tumor relapse (relapse group) during the median follow-up time of 36.5 months (range, 1-242) after surgery with a 5-year overall survival rate of 100 and 10.8%, respectively (P<0.01). No clinicopathological parameters, such as histological type or TNM staging, were associated with tumor relapse. Microarray analysis of 2,630 miRNAs in 11 patients with sufficient quality RNA revealed 12 miRNAs (miR-1260a, -1260b, -1246, -4284, -612, -1249-3p, -296-5p, -575, -6805-3p, -12136, -6822-5p and -4454) that were differentially expressed between the relapse (n=6) and non-relapse (n=5) groups. Furthermore, the top three miRNAs (miR-1246, -1260a and -1260b) were associated with overall survival (P<0.01). These results demonstrated that surgery-based multidisciplinary treatment is effective in a distinct subpopulation of limited stage E-NEC. A specific miRNA gene set is suggested to be associated with treatment outcome.

Diagnostic utility of DNA integrity number as an indicator of sufficient DNA quality in next-generation sequencing-based genomic profiling.

OBJECTIVES: DNA integrity number (DIN) is a metric for assessing DNA degradation, calculated based on electrophoresis using the Agilent TapeStation System. The utility of DIN as a diagnostic indicator of sufficient DNA quality in clinical next-generation sequencing (NGS) has not been well described. METHODS: We evaluated the DINs of 166 tumor formalin-fixed, paraffin-embedded (FFPE) tissue samples submitted for 124-gene panel sequencing. We also investigated a new metric on the electropherogram that could improve the predictive accuracy of the DIN. RESULTS: A DIN cutoff of 2.5 discriminated samples with successful analysis (n = 143) from samples with failed analysis (n = 23), with a sensitivity of 0.84 and a specificity of 0.78 (area under the curve [AUC] = 0.88). The DIN was positively correlated with the mean coverage (r = 0.72, P < .0001) but could not discriminate success from failure when the DIN was below 2.5 (negative predictive value, 0.44). We introduced a new metric, the peak/base ratio, that distinguished success from failure with higher accuracy than the DIN (cutoff = 1.6; sensitivity = 0.98, specificity = 0.83, and AUC =0.96). CONCLUSIONS: To predict successful NGS, the DNA quality of FFPE tissue can be easily and reliably assessed using the DIN and peak/base ratio.

Divided omental flap wrapping a multiple-branched graft replaced with an infected thoracic aortic aneurysm: A case report.

The omental flap is often used to fill the space around the artificial vascular graft as a network sheet to prevent artificial vascular infection. In this study, we report a case in which the omental flap was divided into three parts to fill the dead spaces around the multiple-branched graft, as well as to wrap the suture lines of the graft after graft replacement in a patient with an infected thoracic aorta. An 88-year-old woman was admitted to the hospital with fever and impaired consciousness. Computer tomography revealed an aortic arch aneurysm with enlargement. After emergency stent-graft interpolation and antibiotic treatment, an infected thoracic aortic aneurysm was removed, and a multiple-branched graft replacement of the upper arch was performed. After harvesting an omental flap based on the right gastroepiploic vessels, the omental flap was divided into three on the basis of the epiploic vessels. The middle part of the omental flap was used to fill the space around the lesser curvature of the arch and the distal anastomotic site, the accessory part was used to fill the space between the ascending aorta and the superior caval vein, and the right part was used to wrap the three cervical branches, separately. Fifteen months after surgery, the patient had recovered enough to resume work without any signs of inflammation.

The impact of combined PD-L1 positive score on clinical response to nivolumab in patients with advanced esophageal squamous cell carcinoma.

BACKGROUND: Nivolumab is recommended for patients with advanced esophageal squamous cell carcinoma (aESCC) refractory or intolerant to fluoropyrimidine- and platinum-based chemotherapy regardless of the tumor proportion score (TPS). However, the role of combined positive score (CPS) in predicting nivolumab efficacy remains unclear. We aimed to study whether TPS or CPS is a more suitable biomarker for predicting nivolumab efficacy in these patients. METHODS: We retrospectively collected data from patients with aESCC treated with fluoropyrimidines and platinum and subsequently received nivolumab monotherapy between January 1, 2014 and September 15, 2020. Next, we evaluated the efficiencies of TPS and CPS in predicting the clinical response to nivolumab using PD-L1 IHC 22C3 pharmDx assay. RESULTS: This study included 50 patients (CPS groups: ≥ 10/1-10/ < 1, n = 24/18/8, respectively; TPS groups, ≥ 10%/1%-10%/ < 1%, n = 17/8/25, respectively). The median progression-free survival was 3.2, 2.5, and 1.5 months in the ≥ 10, 1-10 [hazard ratio (HR) vs. CPS of ≥ 10 group, 1.01; p = 0.98; adjusted HR, 1.33; p = 0.56], and < 1 CPS groups (HR vs. CPS of ≥ 10 group, 3.44; p = 0.006; adjusted HR, 1.67; p = 0.41), respectively. For the patients with CPS of ≥ 10/1-10/ < 1 and TPS of ≥ 10%/1%-10%/ < 1%, the objective response rate was 30%/25%/0% and 36%/0%/19% and the disease control rate was 60%/50%/12% (p = 0.06) and 65%/40%/38% (p = 0.30), respectively. CONCLUSIONS: This study suggests that a CPS of < 1 is not a strong predictor of efficacy but can predict the absence of response to nivolumab in patients with aESCC.

Influence of background characteristics in responders of regenerative therapy by periurethral injection of adipose-derived regenerative cells for male stress urinary incontinence.

OBJECTIVES: To determine if the male responders with post-prostatectomy incontinence in the ADRESU study, which is a clinical trial of regenerative therapy by periurethral injection of adipose-derived regenerative cells, are influenced by any background characteristics. METHODS: Briefly, autologous adipose-derived regenerative cells isolated from abdominal adipose tissue and a mixture of adipose-derived regenerative cells with fat tissue were transurethrally injected into the rhabdosphincter and submucosal space of the urethra, respectively. Sixteen out of 43 patients (37.2%) responded to treatment (responders) and exhibited improvement in the urine leakage volume, defined as >50% reduction from baseline determined by the 24-hour pad test at 52 weeks of treatment (or last visit within 52 weeks). Background data such as age, body weight, method of prostatectomy, baseline frequency of leaks, number of leaks, number of pad changes, International Consultation on Incontinence Questionnaire-Short Form, King's Health Questionnaire, urodynamic urethral function including functional profile length and maximum urethral closure pressure, and abdominal leak point pressure were collected and compared between responders and nonresponders. RESULTS: None of the background factors influenced improvement in the responders as compared with the nonresponders. However, a significant between-group difference in the rates of decrease in urine leakage volume was noted in patients of younger age (<70 years), compared with those of older age (≥70 years) from 2 to 26 weeks of treatment. CONCLUSION: A greater decrease in urine leakage volume was noted in the younger patient group than in the older patient group.

Split-dose low-volume polyethylene glycol is non-inferior but less preferred compared with same-day bowel preparation for afternoon colonoscopy.

Currently, the same-day polyethylene glycol-electrolyte lavage solution (PEG-ELS) regimen is particularly recommended for afternoon colonoscopy as an alternative to the split-dose regimen in western countries. However, in Japan, the split-dose regimen has never been used as a standard colonoscopy preparation regimen. The aim of this study was to compare the efficacy and tolerability of split-dose PEG containing ascorbic acid (ASC) with same-day single dose PEG-ASC in Japan.This was a single-blinded, non-inferiority, two-center, randomized, controlled study. In-hospital patients were randomized to the same-day regimen or the split regimen using a web-based registry system. The same-day group was instructed to take 5 mL of sodium picosulfate in the evening, and on the day of the colonoscopy, they took 1.5 L of PEG-ASC. The split group was instructed to take 1 L of PEG-ASC before the day of colonoscopy, followed by another 1 L of PEG-ASC on the day of colonoscopy. Bowel cleansing was evaluated by the Boston Bowel Preparation Scale.A total of 153 patients were randomized to either the same-day group (n=78, males 60.0%, mean age 62.7 years) or the split group (n=75, 61.3%, 61.9 years). The rates of successful bowel cleansing were 83.3% in the same-day group vs. 92.0% (83.4%-97.0%) in the split group, P=0.10). No serious adverse events occurred in the study population. However, more patients in the same-day group were willing to repeat the same preparation regimen (P<0.001). The split-dose regimen was not inferior to the same-day regimen with respect to the efficacy of bowel preparation, but the patients preferred the same-day regimen.

Cultured epidermal autografts for treatment of stable vitiligo: Quantitative analysis of color matching with surrounding normally pigmented skin.

Cultured epidermal autografts (CEA) are surgical therapeutic alternatives for patients with stable vitiligo resistant to conventional medical treatments. In the present study, we assessed color matching before and at 12 months after CEA treatment. Eleven patients with 16 vitiligo lesions were included in this prospective study. The recipient sites were prepared by CO2 laser superficial ablation and subjected to CEA application. We clinically evaluated and categorized the color matching of the repigmented skin as well as the percentage of repigmentation. We also obtained three color values (L*a*b*) for the vitiligo lesions and surrounding normally pigmented skin. We then calculated the color differences between the two regions and compared them before and at 12 months after treatment. The mean percentage of repigmentation was 63.3% at 12 months. Six of the 16 lesions were categorized as "same as" and had color difference values of ≤5 at 12 months after treatment. Clinical evaluation of the color matching coincided well with the calculated color difference values. CEA application after CO2 laser superficial ablation was useful for treating vitiligo assessed by the percentage of repigmentation and color matching. Quantification of color differences may be a useful parameter for evaluating color matching in vitiligo.

An evaluation of resectability among endoscopic treatment methods for rectal neuroendocrine tumors <10 mm.

BACKGROUND AND STUDY AIMS: With respect to rectal neuroendocrine tumor (NET) resection, it remains unclear which of the following methods is the most effective: conventional endoscopic mucosal resection (cEMR), EMR using a fitted cap (EMR-C), EMR with a ligation band device (EMR-L), or endoscopic submucosal dissection (ESD). Thus, in this study, we aim to retrospectively evaluate the most effective endoscopic resection for rectal NETs < 10 mm. PATIENTS AND METHODS: In total, 61 consecutive patients with primary rectal NETs < 10 mm in diameter were included in this study; they were then divided into three groups: those with cEMR; those with modified EMR (mEMR) involving EMR-C and EMR-L; and those with ESD. The primary endpoint was to evaluate the difference in the complete en bloc resection rate. The secondary endpoint was to investigate differences in procedure time and complications. RESULTS: Among the three groups, a significant difference was found in procedure time (cEMR vs ESD, P < .01; mEMR vs ESD, P < .01), en bloc resection rate (cEMR vs mEMR, P = .015), tumor size (mEMR vs ESD, P < .01), percentage of tumor diameter ≥ 5 mm (mEMR vs ESD, P < .01), and complete en bloc resection rate (cEMR vs mEMR, P = .014). Meanwhile, no significant difference was noted in terms of complication rate among the three groups. CONCLUSION: The mEMR was the most suitable resection method for rectal NETs < 10 mm with respect to the risks and benefits from procedure-related factors, such as complete en bloc resection rate, procedure time, and complication rate.

Biological characterization of adipose-derived regenerative cells used for the treatment of stress urinary incontinence.

OBJECTIVE: To assess the characteristics of adipose-derived regenerative cells, and provide supportive data explaining the mechanism of efficacy observed for the use of these cells in the treatment of stress urinary incontinence. METHODS: Adipose tissues were harvested by abdominal liposuction from healthy donors and patients with stress urinary incontinence. Adipose-derived regenerative cells were isolated from tissues using the Celution system, and assessed for their characteristics and ability to differentiate into smooth muscle cells. RESULTS: Adipose-derived regenerative cells isolated by the Celution system developed into fibroblastic colonies. Flow cytometric analysis of adipose-derived stem cell markers showed that adipose-derived regenerative cells were positive for CD34 and CD44, and negative for CD31. Immunofluorescence staining after differentiation showed that colony-forming cells were positive for alpha-smooth muscle actin, calponin and desmin, which are smooth muscle cell markers. A cytokine release assay showed that adherent cells secreted cytokines associated with angiogenesis, including vascular endothelial growth factor-A, angiopoietin-2 and placental growth factor. CONCLUSIONS: Adipose-derived regenerative cells collected by the Celution system might have clonogenic capacity and an angiogenetic function. These properties might contribute to the mechanisms through which regenerative cell therapy by periurethral injection of autologous adipose-derived regenerative cells ameliorates stress urinary incontinence.

O6-methylguanine DNA methyltransferase and glucose transporter 2 in foregut and hindgut gastrointestinal neuroendocrine neoplasms.

BACKGROUND: Streptozocin (STZ) is used for treating both pancreatic (PanNET) and gastrointestinal (GI-NET) neuroendocrine tumors but its therapeutic efficacy is relatively low in GI-NETs. Therefore, it has become pivotal to select GI-NET patients who could benefit from STZ treatment. STZ is transported via the glucose transporter 2 (GLUT2) into the cells and the loss of O6-methylguanine DNA methyltransferase (MGMT) also increases its therapeutic efficacy. Therefore, GLUT2 high and MGMT low status could be the surrogate markers of STZ. METHODS: In this study, we examined the MGMT and GLUT2 status in gastrointestinal neuroendocrine neoplasm (NEN). We studied 84 NEN cases: 33 foregut and 37 hindgut GI-NETs and 14 gastrointestinal neuroendocrine carcinomas (GI-NECs). RESULTS: In GI-NETs, MGMT scores of ≥2 and ≥ 3 were 77% (54/70) and 56% (39/70), respectively, and GLUT2 scores of ≥4 and ≥ 6 were 30% (21/70) and 4.3% (3/70), respectively. Methylation-specific polymerase chain reaction revealed that MGMT promoter methylation was detected only in 2/14 GI-NECs but none of the included GI-NETs. GLUT2 (GLUT2 score) and MGMT immunoreactivity (MGMT and H-scores) were both significantly correlated with Ki-67 labeling index (GLUT2 score: P = 0.0045, ρ = - 0.4570; MGMT score: P = 0.0064, ρ = - 0.4399; H-score: P = 0.0110, ρ = - 0.4135) and MGMT immunoreactivity were significantly correlated with GLUT2 immunoreactivity (MGMT score: P = 0.0198; H-score, P = 0.0004, ρ = 0.5483) in hindgut NETs, but not in foregut NETs. However, discrepancies from the above correlation between GLUT2 and MGMT immunoreactivity were detected in several GI-NET cases which could be potential candidates for STZ therapy. CONCLUSION: The evaluation of MGMT and GLUT2 status could provide an important information in planning STZ therapy in GI-NET patients.

Regenerative treatment for male stress urinary incontinence by periurethral injection of adipose-derived regenerative cells: Outcome of the ADRESU study.

OBJECTIVES: To report the outcome of the ADRESU study, a multicenter, single-arm, investigator-initiated clinical trial to confirm the efficacy and safety of regenerative treatment for male patients with stress urinary incontinence. METHODS: The participants were male patients with mild-to-moderate stress urinary incontinence persisting for >1 year after prostatectomy. Autologous adipose-derived regenerative cells were isolated using the Celution system from adipose tissue obtained by liposuction. Adipose-derived regenerative cells and mixture of adipose-derived regenerative cells with adipose tissue were transurethrally injected into the rhabdosphincter and submucosal space of the urethra, respectively. The primary end-point was the proportion of patients with improvement of the urine leakage volume at 52 weeks (or last visit within 52 weeks). Improvement of leakage volume was defined as a decrease from baseline >50% by the 24-h pad test. A total of 10 secondary end-points were set. RESULTS: A total of 45 patients satisfying the eligibility criteria were enrolled. The primary end-point was met; the proportion of patients with improvement in leakage volume at 52 weeks was 37.2% (95% confidence interval 23.0-53.3%). No serious adverse events with causal relationships to the adipose-derived regenerative cells were encountered. There was a progressive improvement in secondary end-points. In the King's Health Questionnaire, improvement of quality of life scores showed greater improvement in responders, as compared with non-responders. CONCLUSIONS: Findings from the ADRESU study suggest the efficacy and safety of regenerative treatment for male patients with mild-to-moderate stress urinary incontinence.

Breast reconstruction in a patient with an implanted deep brain stimulator.

Deep brain stimulators (DBSs) are sometimes used to treat refractory movement disorders such as Parkinson's disease. When DBSs are implanted in a subcutaneous pocket in the chest region, breast reconstruction becomes a challenge because monopolar electrocautery can lead to DBS dysfunction or brain tissue damage caused by heat. We report a patient with a DBS who underwent one-stage implant-based breast reconstruction. We switched off the DBS before surgery and used monopolar electromagnetic cautery with minimum power settings to undermine the subcutaneous pocket for the breast implant. The DBS was switched back on immediately after completion of the surgery. The patient's postoperative recovery was uneventful with the DBS fully functional.

Variations in clinical features and oncologic behaviors of T1 colorectal cancer according to tumor location.

BACKGROUND: Different genetic characteristics according to tumor location result in variations in survival rates and treatment responses in advanced colorectal cancer (CRC). However, the effects of tumor location during early CRC are still unclear. METHODS: Patients with T1 CRC treated between 2003 and 2019 were enrolled from a prospectively collected database. Patients were once divided into four groups, then combined into two groups (right- and left-sided CRC) according to the tumor location, and clinical features and oncologic behaviors were compared. RESULTS: In total, 458 patients were analyzed. Right-sided CRC had a lower incidence of polypoid type tumor than left-sided CRC (36/126 (28.6%) vs 186/332 (56.0%), p < 0.001). There were no differences in tumor size, pathological grade, pT1 substage and lymphovascular invasion between right- and left-sided CRC. Overall, lymph nodal involvement was observed in 42/458 (9.1%) patients. Right-sided CRC had a lower rate of patients with lymph nodal involvement than left-sided CRC (6/126 (4.8%) vs 36/332 (10.8%), p = 0.04). CONCLUSION: The present study revealed that there were significant differences in the macroscopic type and the incidence of lymph node involvement between right- and left-sided CRC. The clinical features and oncologic behaviors of T1 CRC are possible to vary according to tumor location.

Risk factor analysis for adverse events and stent dysfunction of endoscopic ultrasound-guided choledochoduodenostomy.

BACKGROUND AND AIMS: Although the technique of endoscopic ultrasound-guided choledochoduodenostomy (EUS-CDS) is becoming standardized, its safety issues have not been sufficiently investigated. Therefore, we aimed to identify factors associated with adverse events and stent patency in EUS-CDS. METHODS: Consecutive patients who underwent EUS-CDS between September 2003 and July 2017 were included. Technical/clinical success, adverse events and stent dysfunctions were analyzed retrospectively. RESULTS: A total of 151 patients underwent EUS-CDS. In nine patients, procedures were discontinued before puncture. Technical and clinical success rates were 96.5% (137/142) and 98.5% (135/137), respectively. The adverse event rate was 20.4% (29/142). As a risk factor for peritonitis, plastic stents (PS) showed a significantly high odds ratio (OR) compared with covered self-expandable metal stents (CSEMS; OR, 4.31; P = 0.030). CSEMS cases showed a significantly longer patency period than PS cases (329 vs 89 days; HR, 0.35; P < 0.001). As a risk factor for early stent dysfunction (within 14 days), stent direction to the oral side showed a significantly high OR (OR, 43.47; P < 0.001). In cases with oblique-viewing EUS, double penetration of the duodenum occurred at significantly higher frequency than in cases with forward-viewing EUS (7.0 vs 0.0%; P = 0.024). CONCLUSIONS: Plastic stents and stent direction to the oral side were risk factors for peritonitis and early stent dysfunction, respectively. Using covered self-expandable metal stents and changing stent direction to the anal side seemed appropriate to prevent peritonitis and early stent dysfunction.

Clinical relevance of fluorodeoxyglucose positron emission tomography/computed tomography and magnifying endoscopy with narrow band imaging in decision-making regarding the treatment strategy for esophageal squamous cell carcinoma.

BACKGROUND: Recent advances in endoscopic technology, especially magnifying endoscopy with narrow band imaging (ME-NBI) enable us to detect superficial esophageal squamous cell carcinoma (ESCC), but determining the appropriate method of resection, endoscopic resection (ER) vs surgical resection, is often challenging. Recently, several studies have reported that 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a useful indicator for decision-making regarding treatment for superficial ESCC. Although, there are not enough reports on association between FDG-PET uptake and clinicopathological characteristics of superficial ESCC. And, there are not enough reports on evaluating the usefulness of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC. This study evaluated clinical relevance of FDG-PET and ME-NBI in decision-making regarding the treatment strategy for ESCC. AIM: To investigate the association between FDG uptake and the clinicopathological characteristics of superficial ESCC and its usefulness of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC. METHODS: A database of all patients with superficial ESCC who had undergone both ME-NBI and FDG-PET for pre-treatment staging at Aichi Cancer Center Hospital between January 2008 and November 2018 was retrospectively analyzed. FDG uptake was defined positive or negative whether the primary lesion was visualized or could be distinguished from the background, or not. The invasion depth of ESCC was classified according to the Japan Esophageal Society. Primary endpoint is to evaluate the association between FDG uptake and clinicopathological characteristics of superficial ESCC. Secondary endpoint is to investigate the efficacy of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC. RESULTS: A total of 82 lesions in 82 patients were included. FDG-PET showed positive uptake in 29 (35.4%) lesions. Univariate analysis showed that uptake of FDG-PET had significant correlations with circumferential extension (P = 0.014), pathological depth of tumor invasion (P < 0.001), infiltrative growth pattern (P < 0.001), histological grade (P = 0.002), vascular invasion (P = 0.001), and lymphatic invasion (P < 0.001). On multivariate analysis, only depth of tumor invasion was independently correlated with FDG-PET/computed tomography visibility (P = 0.018). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of Type B2 in ME-NBI for the invasion depth of T1a muscularis mucosae and T1b upper submucosal layer were 68.4%/79.4%/50.0%/89.3%/76.8%, respectively, and those of Type B3 for the depth of T1b middle and deeper submucosal layers (SM2 and SM3) were 46.7%/100%/100%/89.3%/90.2%, respectively. On the other hand, those of FDG-PET for SM2 and SM3 were 93.3%/77.6%/48.2%/98.1%/80.5%, respectively, whereas, if the combination of positive FDG uptake and type B2 and B3 was defined as an indicator for radical esophagectomy or definitive chemoradiotherapy, the sensitivity, specificity, PPV, NPV, and accuracy were 78.3%/91.5%/78.3%/91.5%/87.8%, respectively. CONCLUSION: FDG uptake was correlated with the invasion depth of superficial ESCC. Combined use of FDG-PET and ME-NBI, especially with the microvascular findings of Type B2 and B3, is useful to determine whether ER is indicated for the lesion.