Search

Endoscopic resection (ER) is performed for early esophageal squamous cell carcinoma (ESCC) cases. Additional esophagectomy or chemoradiotherapy is recommended for non-curative resection (NCR) even with pathologically negative vertical margins (pVM0); however, their clinical outcomes remain unknown. We examined the long-term clinical outcomes of NCR for ESCCs according to additional treatments.We retrospectively analyzed the data of patients who underwent ER for cT1N0M0 ESCC between 2009 and 2017 judged to have NCR, which defined when pathologically diagnosed as invading the submucosa (SM) or muscularis mucosae (MM) involving lymphovascular invasion (LVI), pVM0, and endoscopically judged as negative horizontal margin. Additional esophagectomy (involving three-field lymphadenectomy), chemoradiotherapy [mainly cisplatin and 5-fluorouracil with concurrent radiotherapy (41.4 Gy)], or observation was undertaken. Thereafter, computed tomography was performed every 6-12 months. The cumulative recurrence (CRR) and recurrence-free survival (RFS) rates were evaluated.Eighty-nine patients were included. Among them, 14 had pathologically diagnosed pMM with LVI; 9 and 6, and 32 and 28 patients had pSM1 and pSM2 without and with LVI. Twenty-one patients underwent observation, whereas 18 and 50 underwent esophagectomy and chemoradiotherapy. During the 60.6-month median follow-up period, nine patients had recurrence; among them, six patients had occurrence at 4 years after ER. The 5-year CRR/RFS rates were 35.7%/48.1%, 13.4%/80.4%, and 0.0%/98.0% in the observation, esophagectomy, and chemoradiotherapy groups, respectively (observation vs. chemoradiotherapy; P 0.001).Additional treatments showed better long-term outcomes than observation for patients with NCR. As recurrence may occur at 4 years after ER, careful long-term follow-up examinations are needed.

OBJECTIVES Photodynamic therapy (PDT) is an optional salvage treatment for local failure of esophageal squamous cell carcinoma (ESCC) after chemoradiotherapy; however, local failure after PDT sometimes occurs. In such cases, second PDT is sometimes attempted, but its outcomes remain unclear. This study aimed to evaluate the efficacy and safety of second PDT. METHODS We enrolled patients who underwent PDT for local failure of ESCC after chemoradiotherapy. We retrospectively evaluated local-complete response (L-CR) rate and clinical outcomes of first and second PDT. The indications for PDT were lesions within the muscle layer

Background The Cryoballoon focal ablation system (CbFAS) for dysplastic Barrett’s esophagus is simple, time-saving and has high therapeutic efficacy. This study aimed to evaluate the technical feasibility and tissue damage with combination therapy of endoscopic resection (ER) and CbFAS in porcine models. Methods Three pigs (A, B, and C) were included, and all ER procedures were performed by endoscopic mucosal resection using the Cap method (EMR). Combination therapy for each pig was performed as follows: (a) CbFAS was performed for a post-EMR mucosal defect for Pig A; (b) CbFAS for post-EMR scar for Pig B, and (c) EMR for post-CbFAS scar for Pig C. All pigs were euthanized at 32 days after the initial procedure, and the tissue damage was evaluated. Results All endoscopic procedures were followed as scheduled. None of the subjects experienced anorexia, rapid weight loss, bleeding, and perforation during the observation period. They were euthanized at 32 days after the initial endoscopic procedure. On histological assessment, there was little difference between the tissue that was treated with CbFAS alone and that treated with CbFAS in combination with ER. Conclusion Combination therapy with ER and CbFAS can be technically feasible, and its outcome was not significantly different from CbFAS alone in terms of tissue damage.

A drawback of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) is the development of metachronous gastric cancer (MGC). While MGC after ESD for differentiated-type (D-) EGC was well understood, little is known about MGC occurring after ESD for undifferentiated-type (UD-) EGC, because ESD had not been indicated. We evaluated the incidence and treatment outcomes of MGC after ESD of UD-EGC. This study is a post hoc analysis of JCOG1009/1010, a multicenter trial to evaluate the efficacy and safety of ESD for UD-EGC. The patients who underwent curative ESD of index solitary UD-EGC were analyzed. Surveillance endoscopy was performed biannually for the first 3 years and thereafter annually. We assessed the time to MGC occurrence after ESD, lesion characteristics, and treatment outcomes of MGC. Time to MGC occurrence was estimated by cumulative incidence function, with death and total gastrectomy as competing risks. A total of 198 patients were included in this study. During a median follow-up period of 5.8 years, 4 patients (2%) developed MGC. Median time to MGC occurrence was 4.5 years (range: 3.1–5.4). Five-year cumulative incidence of MGC was 1.0% (95% CI: 0.2–3.3%). Two MGCs were histologically D-EGC, and the remaining two were UD-EGC. The median tumor size of MGCs was 1.0 cm (range: 0.7–1.7), and the depth of invasion (M/SM1/SM2) was 2/1/1, respectively. Three patients achieved curative resection with repeated ESD. MGC does not occur commonly after curative ESD of UD-EGC, and repeated ESD could contribute to stomach preservation.

Background Improvements in early detection and treatment have resulted in an increasing number of long-term survivors of colorectal cancer (CRC). For the survivors, second primary cancer and recurrence are important issues; however, evidence for an appropriate surveillance strategy remains limited. This study aimed to investigate the frequency and timing of second primary cancer in patients after surgery for exploring an appropriate surveillance strategy by using an integrated analysis of three large-scale randomized controlled trials in Japan. Methods The eligibility criteria of three trials included histologically confirmed CRC and having received surgery. The timing, site and frequency of second primary cancers and recurrence were investigated. Risk factors associated with second primary cancers were also examined. The standardized incidence ratio (SIR) of second primary cancers compared with the national database of the Japan Cancer Registry was estimated. Results A total of 2824 patients were included in this study. The cumulative incidence of second primary cancer increased over time. The SIR of any second primary cancer was 1.07 (95% CI: 0.94–1.21). The SIR for second primary cancers of colon was 1.09 (95% CI: 0.79–1.47). The cumulative incidence of recurrence almost reached plateau at 3 years. Conclusions A common surveillance strategy for the general population can be applied even for curatively resected CRC patients, as the risk of second primary cancers was almost the same as that of the general population.

Prediction of the invasive depth is the objective of endoscopic observation for digestive cancer. In superficial esophageal cancer, a close relationship between microvascular patterns observed by magnifying endoscopy with narrow-band imaging (M-NBI) and pathological depth of invasion is well known. The ability of M-NBI to predict the invasion depth in superficial pharyngeal squamous cell carcinoma (SPSCC) has been seldom evaluated. This study aimed to clarify the relationship between the microvasculature patterns and pathological depth in SPSCC. SPSCC lesions evaluated with M-NBI followed by endoscopic resection were analyzed between April 2010 and March 2017. Endoscopic images were classified as microvasculature tumor types B1, B2, and B3 according to the Japan Esophageal Society classification. The pathological depth of invasion was described as either squamous cell carcinoma in situ (Tis) or invasive subepithelial cancer, and the tumor thickness of all lesions was examined. Data were analyzed using the unpaired t, χ2, or Mann–Whitney U test. Type B1 and type B2/B3 (35/3) microvessels were found in 180 lesions (82%) and 39 (18%), respectively. Of the flat lesions, 115 (83%) were classified as Tis and 23 (17%) as subepithelial cancer. Positive and negative predictive values of the B1 vessels were 77% and 82%, respectively. Additional analysis showed that the positive predictive value of the B1 vessels for the flat-type lesions was 87%; the negative predictive value for the elevated lesions was 93%. Microvascular patterns observed by M-NBI are an important factor in predicting the pathological depth of invasion.

Local recurrence after definitive chemoradiotherapy, if diagnosed early, can be cured by salvage endoscopic therapy, which allows organ preservation and contributes to maintaining patient quality of life. This study aimed to investigate early endoscopic findings of local recurrence in post-definitive chemoradiotherapy patients. Between January 2008 and June 2012, 17 esophageal squamous cell carcinoma patients with no metastasis but local recurrence after definitive chemoradiotherapy were enrolled. We attempted to find endoscopic hallmarks suggestive of local recurrence by comparing pre- and post-local recurrence diagnostic images. The influence of follow-up schedule on chosen salvage therapy type was also investigated. Endoscopic local recurrence findings included eight submucosal tumors, five ulcers, and four erosions. Upon review of prior images, findings suggestive of local recurrence were detected in seven patients, including six submucosal tumors and one erosion, all of which were smaller than 10 mm. These lesions had changed morphologically at local recurrence diagnosis: three submucosal tumors had become larger and three submucosal tumors and one erosion had changed to ulcers. Of 12 patients with cT1 at local recurrence, four (33%) underwent follow-up endoscopy within 1 month of local recurrence findings and 11 patients (92%) were treated with salvage endoscopic therapy. Endoscopists should be aware that SMTs or erosions, even those smaller than 10 mm, can indicate local recurrence after complete response to definitive chemoradiotherapy. Follow-up endoscopy should be performed within 1–2 months if findings suggestive of local recurrence are observed on prior endoscopy, even when biopsy results are negative.

Immune checkpoint inhibitors may enhance the efficacy of radiotherapy (RT) in cancer treatment but the effect remains unknown in metastatic gastric cancer (mGC). This study aimed to compare the tumor shrinkage by palliative RT for mGC patients with or without previous exposure to anti-PD-1 therapy. Data of 36 mGC patients who had received palliative RT from April 2013 to May 2019 were analyzed. Primary tumor responses were evaluated through a volumetric measurement-based method using computed tomography (CT) and endoscopic responses were evaluated in patients who underwent endoscopy before and after RT. Tumor microenvironment (TME) immune status was investigated by analyzing tumor-infiltrating lymphocytes by flow cytometry. Among 36 patients, 18 had previous exposure to anti-PD-1 before RT showing no significant differences in baseline characteristics with the other 18 patients without exposure to anti-PD-1 treatment. Tumor responses were observed in 28% (5/18) and none (0/18) in the anti-PD-1-exposed vs. naive group, respectively (P = 0.045). Five out of eight patients in the anti-PD-1-exposed group, who underwent endoscopy after RT showed partial response, but none in the anti-PD-1-naive patients showed response (P = 0.026). Increase in the CD8+ T cell/effector regulatory T cell ratio in TILs after anti-PD-1 therapy was noted in three responders to RT, but not in the other three non-responders. Prior exposure to anti-PD-1 therapy increases tumor response to RT. Immune profiling suggests that anti-PD-1 therapy may enhance the efficacy of RT by immunoactivation in the TME.

The width of mucosal defects after endoscopic submucosal dissection (ESD) of esophageal squamous cell carcinoma (ESCC) is known to be a risk factor for esophageal strictures. Although steroid injection and oral steroid have recently been reported as prophylactic treatments, these were shown to be ineffective in a subset of patients with post-ESD mucosal defects involving the entire circumference of the esophagus. The aim of this study was to demonstrate outcome with prophylactic steroid administration for post-ESD mucosal defects involving the entire circumference, and to explore risk factors for esophageal strictures except for circumference of the esophagus. Between November 2012 and August 2018, we enrolled patients with post-ESD mucosal defects involving the entire circumference of the esophagus who had received steroid injection (triamcinolone acetonide 50–100 mg, given immediately after ESD) followed by oral steroid (prednisolone 30 mg/day, tapered gradually over 8 weeks) as prophylactic treatment. Esophageal stricture was defined as case where ordinary-sized endoscope could not pass through post-ESD site, thus requiring endoscopic balloon dilation (EBD) repeatedly until relief of stricture was achieved. We retrospectively evaluated the rates of strictures, refractory strictures (requiring ≥ 6 EBD procedures) and unimproved strictures (not improvable by repeated EBD alone) and explored risk factors for strictures. A total of 26 patients met the including criteria. The rates of strictures, refractory strictures, and unimproved strictures were 62%, 38%, and 12%, respectively. The pre-ESD longitudinal extension of the lesion > 5 cm was identified as a risk factor for refractory strictures, suggesting that lesions with this factor had a shorter time to stricture development, required more EBD procedures, and longer EBD durations. Although additional study is required in a larger number of patients, careful consideration needs to be given to ESD as an indication for large spreading ESCC involving the entire circumference of esophagus given its high stricture risk.

OBJECTIVES S-1 monotherapy with concurrent radiotherapy (RT) is a standard of care for patients with locally advanced pancreatic cancer (LAPC). Although renal dysfunction increases S-1 monotherapy toxicity, its effect in S-1 with concurrent RT remains unknown. We evaluated the effect of renal function on the safety of S-1 with RT for LAPC. METHODS We performed an integrated exploratory post hoc analysis of data from 2 prospective studies (JCOG1106 and LAPC-S1RT), where patients with LAPC received RT (50.4 Gy/28 fraction for 5.5 weeks) and concurrent S-1 (40 mg/m2 per dose, twice daily on the day of irradiation). We split the patients into high creatinine clearance (CCr; ≥80 mL/min) and low CCr (

Endoscopic submucosal dissection (ESD) is the standard treatment for cT1a esophageal squamous cell carcinoma (ESCC), however its indication for the entire circumferential lesions is still controversial because of the risk of severe stricture after ESD. Therefore, several treatment options are performed based on physicians’ choice, however, each clinical course is unclear. This study aimed to clarify the long-term outcome after ESD for patients with entire circumferential cT1aN0M0 ESCC, comparing with esophagectomy or chemoradiotherapy. Methods Patients with entire circumferential cT1aN0M0 SESCC treated with ESD, chemoradiotherapy, or esophagectomy as the initial treatment between January 2010 and December 2016 in our institution were included. Patients who had a history of any malignancy at cStage II-IV within 5 years were excluded. The 5-year overall survival (OS), 5-year disease-free survival (DFS), stricture rate, refractory stricture rate (defined as requiring >6 dilations), curative resection (defined as pT1a without lymphovascular invasion and negative for vertical margin in the pathological evaluation) rate of ESD, and complete response rate of chemoradiotherapy were evaluated for each treatment. Results Of the 48 eligible patients, 25/13/10 patients were performed ESD/chemoradiotherapy/esophagectomy as an initial treatment. Curative resections rate of ESD was 72%, and additional esophagectomy and chemoradiotherapy were performed in three and one patients with non-curative resection. Complete response rate of chemoradiotherapy was 100%, however, 4 patients had recurrence thereafter. No recurrences occurred after esophagectomy in all patients treated with esophagectomy. During median follow-up of 83 months, stricture and refractory stricture rate was 80/44% after ESD, 0/0% after chemoradiotherapy, and 20/10% after esophagectomy. The 5-year OS/DFS was 91/87% after ESD, 92/59% after chemoradiotherapy, and 90/90% after esophagectomy. Conclusion While some patients required additional treatments due to non-curative resection, the long-term survival after ESD for circumferential cT1aN0M0 ESCC was similar as those after chemoradiotherapy or esophagectomy. In contrast, the stricture and refractory stricture rate after ESD was higher than others. Further investigation in a large cohort is necessary to clarify the indication criteria of ESD for patients with the lesion.

The diagnosis of gastrointestinal stromal tumor (GIST) using conventional endoscopy is difficult because submucosal tumor (SMT) lesions like GIST are covered by a mucosal layer. Near-infrared hyperspectral imaging (NIR-HSI) can obtain optical information from deep inside tissues. However, far less progress has been made in the development of techniques for distinguishing deep lesions like GIST. This study aimed to investigate whether NIR-HSI is suitable for distinguishing deep SMT lesions. In this study, 12 gastric GIST lesions were surgically resected and imaged with an NIR hyperspectral camera from the aspect of the mucosal surface. Thus, the images were obtained ex-vivo. The site of the GIST was defined by a pathologist using the NIR image to prepare training data for normal and GIST regions. A machine learning algorithm, support vector machine, was then used to predict normal and GIST regions. Results were displayed using color-coded regions. Although 7 specimens had a mucosal layer (thickness 0.4-2.5 mm) covering the GIST lesion, NIR-HSI analysis by machine learning showed normal and GIST regions as color-coded areas. The specificity, sensitivity, and accuracy of the results were 73.0%, 91.3%, and 86.1%, respectively. The study suggests that NIR-HSI analysis may potentially help distinguish deep lesions.

Background Recently, the JCOG0502 has shown a comparable efficacy of chemoradiotherapy and esophagectomy in patients with clinical T1N0M0 esophageal squamous cell carcinoma. However, few studies have compared the clinical outcomes of these treatments in esophageal squamous cell carcinoma patients (including elderly patients) based on real-world data. Methods This retrospective study determined real-world outcomes in patients who underwent chemoradiotherapy or esophagectomy, including those with clinical T1N0M0 esophageal squamous cell carcinoma, between 2009 and 2017 at the National Cancer Center Hospital East. Results Among a total of 156 patients, 120 and 36 patients underwent esophagectomy and chemoradiotherapy, respectively; 138, 12 and 6 patients had Eastern Cooperative Oncology Group performance status 0, 1, and 2, respectively; and 33 and 123 patients had clinical tumor depth MM-SM1 and SM2-SM3, respectively. In a median follow-up of 72 months, 5-year progression-free survival and overall survival were respectively 77.0% and 81.5% in the esophagectomy group and 74.4% and 82.6% in the chemoradiotherapy group (P = 0.48 and, P = 0.89). Moreover, no treatment-related death was detected in both groups. In elderly patients (75 years or older), 5-year progression-free survival and overall survival were not significantly different between esophagectomy and chemoradiotherapy groups (5-year progression-free survival: 72.3% vs. 81.8%, P = 0.38; 5-year overall survival: 76.9% vs. 81.8%, P = 0.59). Conclusions This real-world study confirms the results of a previous clinical trial, and the present findings support chemoradiotherapy as one of the standard treatment options in patients of all ages with clinical T1N0M0 esophageal squamous cell carcinoma.

A randomized phase III trial commenced in Japan in February 2018. Definitive chemoradiotherapy (CRT) with cisplatin plus 5-fluorouracil is the current standard treatment for locally advanced unresectable esophageal carcinoma. The purpose of this study is to confirm the superiority of induction chemotherapy with docetaxel plus cisplatin and 5-fluorouracil (DCF) followed by conversion surgery or definitive CRT over definitive CRT alone for overall survival (OS) in patients with locally advanced unresectable squamous-cell carcinoma of thoracic esophagus. A total of 230 patients will be accrued from 47 Japanese institutions over 4.5 years. The primary endpoint is OS, and the secondary endpoints are progression-free survival, complete response rate of CRT, response rate of DCF, adverse events of DCF and CRT, late adverse events and surgical complications. This trial has been registered at the Japan Registry of Clinical Trials as jRCTs031180181.

There are few reports on the technical difficulty of gastric endoscopic submucosal dissection (ESD). The aim of this study was to investigate the factors associated with the technical difficulty of ESD for early gastric cancer (EGC) using the data from the multicenter non-randomized confirmatory trial of expanded indication criteria of ESD (JCOG0607).The major inclusion criteria were as follows: (1) histologically proven intestinal-type adenocarcinoma; (2) cT1aN0M0; (3) lesion without finding of ulcer (UL-negative) with 2 cm in size, or UL-positive with ≤ 3 cm; (4) age 20-75 years. The difficult case was defined as ESD taking ≥ 120 min, piecemeal resection, and/or developing perforation during procedure.Between June 2007 and October 2010, 470 patients were enrolled from 29 institutions. Median procedure time was 79 (range 14-462) min, and it was ≥ 120 min in 127 patients. Twelve patients developed perforation during ESD, and the procedure time was ≥ 120 min in 9 of them. Therefore, 130 patients (27.7%) were identified as difficult cases. Multivariable analysis showed that UL-negative with 5 cm (vs. UL-negative with ≤ 3 cm, odds ratio, 24.993; 95% CI 6.130-101.897, p 0.0001) had the largest odds ratio and followed by UL-negative with 3-5 cm upper or middle portion of stomach and age ≤ 60 years were significantly associated with difficulty.UL-negative lesion with 3 cm, upper or middle portion of stomach and age ≤ 60 years were independent factors associated with technical difficulty of ESD for EGC. Trial registered number was UMIN000000737.

JCOG9801, a randomized phase III trial, reported that vincristine, cyclophosphamide, doxorubicin and prednisone (VCAP); doxorubicin, ranimustine and prednisone (AMP); and vindesine, etoposide, carboplatin and prednisone (VECP) (VCAP-AMP-VECP; mLSG15) showed superior clinical outcomes when compared to cyclophosphamide, doxorubicin, vincristine and prednisone every 2 weeks (CHOP-14; mLSG19) in patients with untreated aggressive adult T-cell leukaemia-lymphoma (ATL). To identify patients who require VCAP-AMP-VECP, we conducted a supplementary analysis of JCOG9801. Overall, 105 patients were included and categorized into low- (n = 44), intermediate- (n = 54) and high-risk (n = 7) groups according to the age-adjusted ATL prognostic index (ATL-PI). We excluded the high-risk group due to small numbers of patients. VCAP-AMP-VECP did not show any superior trend for overall survival (OS) in the low-risk group (hazard ratio: 1·04; 95% confidence interval: 0·54-2·04). Better OS was observed in the intermediate-risk group treated with VCAP-AMP-VECP (hazard ratio: 0·65; 95% confidence interval: 0·36-1·19). In the intermediate-risk group, the VCAP-AMP-VECP arm showed higher complete response rates than the CHOP-14 arm (44·0% vs. 13·8%). The VCAP-AMP-VECP arm in both risk groups exhibited grade 4 thrombocytopenia, while grade 4 neutropenia was only observed in the intermediate-risk group. VCAP-AMP-VECP remains suitable for the intermediate-risk group, whereas its benefits appear modest in the low-risk group.

The diagnosis of gastrointestinal stromal tumor (GIST) using conventional endoscopy is difficult because submucosal tumor (SMT) lesions like GIST are covered by a mucosal layer. Near-infrared hyperspectral imaging (NIR-HSI) can obtain optical information from deep inside tissues. However, far less progress has been made in the development of techniques for distinguishing deep lesions like GIST. This study aimed to investigate whether NIR-HSI is suitable for distinguishing deep SMT lesions. In this study, 12 gastric GIST lesions were surgically resected and imaged with an NIR hyperspectral camera from the aspect of the mucosal surface. Thus, the images were obtained ex-vivo. The site of the GIST was defined by a pathologist using the NIR image to prepare training data for normal and GIST regions. A machine learning algorithm, support vector machine, was then used to predict normal and GIST regions. Results were displayed using color-coded regions. Although 7 specimens had a mucosal layer (thickness 0.4–2.5 mm) covering the GIST lesion, NIR-HSI analysis by machine learning showed normal and GIST regions as color-coded areas. The specificity, sensitivity, and accuracy of the results were 73.0%, 91.3%, and 86.1%, respectively. The study suggests that NIR-HSI analysis may potentially help distinguish deep lesions.

Endoscopic ultrasonography (EUS) is reportedly the reliable modality to predict the depth of esophageal squamous cell carcinoma (ESCC), however, most previous studies are retrospective or single-centered. We aimed to evaluate the diagnostic ability of conventional endoscopy and EUS using the data from a multicenter prospective study of endoscopic resection (ER) followed by chemoradiotherapy for cSM1-2N0M0 ESCC (JCOG0508). All lesions were evaluated as cSM cancer with both conventional endoscopy and EUS before enrollment and judged as cSM1 or cSM2 in real time. We compared the clinical and pathological diagnoses for tumor depth and assessed the positive predictive value (PPV) for pSM (pSM/cSM) as the primary endpoint. We also investigated the clinical factors affecting the pathological depth of SM. 175 lesions were examined, and clinical diagnosis was SM1 in 114 and SM2 in 61 lesions. The pathological diagnoses of the epithelium, lamina propria mucosa, muscularis mucosae, SM1, and SM2 were 3, 31, 55, 17, and 69. The PPV for pSM was 49.1% (86/175) in all lesions, 34.2% (39/114) in cSM1 lesions, and 77.0% (47/61) in cSM2 lesions. Multivariable analysis demonstrated that cSM2 (vs. cSM1, OR 6.79) was an independent clinical factor associated with pSM. While the accurate depth diagnosis in cSM ESCC was difficult to make, the clinical diagnosis of SM2 with both conventional endoscopy and EUS was significantly associated with pSM. Furthermore, diagnostic ER could be recommended to confirm the pathological diagnosis especially in cSM1 lesions with both conventional endoscopy and EUS.

Gastric cancer is the most frequent primary cancer-associated with esophageal cancer and is most commonly detected by endoscopic surveillance. However, the clinical features of synchronous or metachronous gastric cancer that could be detected by esophagogastroduodenoscopy in esophageal cancer patients are unknown. We reviewed the clinical records of all esophageal cancer patients (n = 1379) registered in the cancer registration database who underwent initial treatment between April 2010 and October 2015. We retrospectively analyzed the proportions of synchronous and metachronous gastric cancer cases, the cumulative incidence rate of metachronous gastric cancer in total and by esophageal cancer treatments (endoscopic resection, esophagectomy, and chemoradiotherapy), and the clinical features of esophageal cancer patients with synchronous or metachronous gastric cancer. Overall, 67 (5.3% of 1275) esophageal cancer patients with synchronous gastric cancer and 40 (5.1% of 791) esophageal cancer patients with metachronous gastric cancer were analyzed. The 5-year cumulative incidence rate of metachronous gastric cancer was 5.6% in total, 7.8% after endoscopic resection, 4.7% after esophagectomy, and 4.1% after chemoradiotherapy for esophageal cancer. From the results of multivariate analysis, the risk factors for synchronous gastric cancer were male (odds ratio 13.3) and moderate/severe atrophic gastritis (odds ratio 17.9), and the risk factor of metachronous gastric cancer was moderate/severe atrophic gastritis (hazard ratio 27.6) in patients with esophageal cancer. The incidence rates of synchronous and metachronous gastric cancer with esophageal cancer were both over 5%. Careful endoscopic observation is required for moderate and severe atrophic gastritis at detecting concomitant gastric cancer in esophageal cancer patients.

Little is known about the incidence of metachronous advanced neoplasia (AN) following resection of submucosal invasive colorectal cancer (SM-CRC). Here, we aimed to assess the occurrence of metachronous AN following SM-CRC resection. We retrospectively reviewed consecutive patients who underwent SM-CRC resection at an academic medical center between 2005 and 2013. Among 343 patients, 250 (72.9%) underwent surgical resection or endoscopic resection followed by surgical resection and 93 (27.1%) underwent only endoscopic resection. During a median follow-up period of 61.5 months, the overall incidence of metachronous AN was 7.6%, and the cumulative incidence at 5 years was 6.1%. The cumulative incidence was significantly higher in the endoscopic resection group than in surgical resection group, in patients with colonic disease than in those with rectal disease, and in patients with synchronous AN than in those without. Multivariate analysis revealed that synchronous AN was the only significant risk factor for metachronous AN (HR 4.35; 95% CI 1.88–10.1). These findings imply that depending on synchronous AN, a surveillance protocol following SM-CRC resection can be changed for better detection of metachronous AN.

Background and Aims Lymph node recurrence (LNR) after endoscopic resection (ER) in patients with esophageal squamous cell carcinoma (ESCC) invading the muscularis mucosae (pMM) without lymphovascular invasion (LVI) has been reported as non-negligible in the ER guidelines for esophageal cancer by the Japan Gastroenterological Endoscopy Society. However, these data were not regarded as high-level evidence because several retrospective case series were tabulated without sufficient long-term follow-up. Hence, this guideline stated that the administration of additional treatment after ER could not be determined for this population. This study aimed to clarify the long-term clinical outcomes after ER of pMM ESCC without LVI. Methods Between January 2009 and November 2017, we enrolled followed-up patients who underwent ER and were pathologically diagnosed with pMM ESCC without LVI without additional treatments. We retrospectively investigated the cumulative recurrence rate and recurrence-free, overall, and disease-specific survival at 5 years after ER. Results Eighty-seven patients were enrolled. During the median follow-up period of 64 months (range: 12–117), 3 patients developed lymph node and/or distant recurrence, and 2 of these cases occurred more than 3 years after ER; all 3 patients died of the primary disease. The 5-year cumulative recurrence rate was 4.3%, and the 5-year recurrence-free, disease-specific, and overall survival rates were 88.8%, 98.2%, and 91.7%, respectively. Conclusions The long-term outcome for patients with pMM ESCC without LVI was favorable after ER; however, this population had a risk of recurrence directly leading to death. Long-term follow-up is necessary, with attention to the timing of recurrence.

Tumor regression grade of the primary tumor (TRG-PT) and residual lymph node metastasis have been pathologically determined in esophageal squamous cell carcinoma (ESCC) patients who had received neoadjuvant chemotherapy (nCT) followed by surgery; however, TRG of the metastatic tumor involving lymph nodes (LN) has not yet been determined. The aim of the present study was to clarify the impact of TRG on the prognosis of ESCC patients. ESCC patients (n = 110) who had received nCT followed by surgery were enrolled. Dissected LN were classified into 2 categories: plausible positive metastatic LN (pp-MLN) where viable and/or degenerated ESCC cells and/or tissue modifications were observed, and non-metastatic LN (non-MLN) where neither of them was observed. We defined nCT-effective rate (CER) as the ratio of the number of pp-MLN that showed tumor regression to the total number of pp-MLN, and divided CER into low-CER (LCER; ≥0% and

Background and study aims Visual assessment of laterally spreading tumors non-granular type (LST-NG) and depressed lesions by narrow band imaging (NBI) without magnification has not been studied. We investigated the role of non-magnifying NBI in detecting LST-NG and type IIc lesions on colonoscopy. Patients and methods This retrospective study examined consecutive patients diagnosed as having LST-NG and/or type IIc lesions in our hospital between August 2011 and July 2013. These lesions were classified as “Brownish area (BA),” “Brown only in the margins (O-ring sign),” “Same color as the normal mucosa (SC),” and “Whitish area (WA)” based on their appearance on non-magnifying NBI, and their appearance were compared with their histopathological findings. Results A total of 18 type IIc and 180 LST-NG lesions were analyzed. Among the type IIc lesions, 5 (28 %), 12 (67 %), and 1 (5 %) were classified as BA, O-ring sign, and SC, respectively. Among the LST-NG lesions, 126 (70 %), 26 (14 %), and 28 lesions (16 %) were classified as BA, O-ring sign, and SC, respectively. The IIc lesions were found to have 1 lesion (20 %) with high-grade dysplasia (HGD) in the BA, and 2 lesions (17 %) with invasive cancer (IC) in the O-ring sign group. Among the LST-NG lesions, 27 (21 %) were found to have IC and 49 (39 %), HGD in the BA group; 8 lesions (31 %) had IC and 4 (15 %) had HGD in the O-ring sign group; and 1 lesion (4 %) had IC and 4 (14 %) had HGD in the SC group. Conclusions Most flat and depressed colorectal lesions were seen on non-magnifying NBI as brown lesions with the exception of some flat lesions that were indistinguishable in color from the adjacent normal mucosa. Some of these flat lesions were also found to have HGD or IC.

Background and aim Salvage endoscopic resection (ER) is among the curative treatments for superficial local failure after chemoradiotherapy (CRT) for esophageal squamous cell carcinoma (ESCC). The present study aimed to clarify risk factors for recurrence after salvage ER. Methods This study enrolled consecutive ESCC patients treated with salvage ER for local failure after CRT between 1998 and 2013. Recurrences after salvage ER included locoregional recurrences and distant metastases. Multivariate analysis was carried out on clinicopathological parameters to identify risk factors for post-salvage ER recurrence. Results Of the 72 patients enrolled in this study, 37/8/23/4 patients had been staged before CRT as cT1/T2/T3/T4 and 44/28 patients as cN0/N1, respectively, and local failures detected before salvage ER were residual lesions after CRT in 19 and local recurrences in 53 patients. Resected specimens were classified as pT1a (M) in 45 and pT1b (SM) in 27 patients. During the median 45-month follow up (range, 3-175 months) after salvage ER, 27 (38%) patients developed recurrence with a 3-year recurrence-free survival rate of 48.9% (95% confidence interval [CI], 36.5-60.3). Multivariate analysis showed that residual lesions after CRT (HR, 2.55; 95% CI, 1.32-4.94) and lesions with a submucosal tumor (SMT)-like appearance before salvage ER (HR, 2.08; 95% CI, 1.04-4.18) were significantly associated with post-salvage ER recurrence. Conclusions Clinical findings (e.g. residual tumors found immediately after CRT and macroscopic SMT-like appearance before salvage ER) were shown to be significant risk factors for post-salvage ER recurrence.

A randomized phase III trial was initiated in Japan in August 2019 to confirm the superiority of preoperative chemoradiotherapy followed by surgery plus adjuvant chemotherapy compared to the standard treatment, i.e. surgery plus adjuvant chemotherapy, for locally recurrent rectal cancer in local relapse-free survival. In all, 110 patients from 43 Japanese institutions will be recruited over a period of 6 years. Eligible patients would be registered and randomly assigned to each group with an allocation ratio of 1:1. The primary endpoint is local relapse-free survival. The secondary endpoints are overall survival, relapse-free survival, proportion of local relapse, proportion of distant relapse, proportion of patients with pathological R0 resection, response rate of preoperative chemoradiotherapy (preoperative chemoradiotherapy arm), pathological complete response rate (preoperative chemoradiotherapy arm), proportion of patients who completed the protocol treatment, incidence of adverse events (adverse reactions) and quality of life after surgery. This trial has been registered at the Japan Registry of Clinical Trial: jRCTs031190076 [https://jrct.niph.go.jp/latest-detail/jRCTs031190076] and ClinicalTrials.gov: NCT04288999 [https://clinicaltrials.gov/ct2/show/NCT04288999].

Proton beam therapy (PBT) with concurrent chemotherapy is promising for esophageal squamous cell carcinoma (ESCC). The aim of study was to evaluate the outcome of concurrent chemo-proton therapy (CCPT), i.e., PBT with concurrent chemotherapy for cT1 ESCC and the salvage endoscopic therapy for local recurrence. Patients with clinical T1 ESCC who underwent CCPT (60 GyE) between April 2013 and April 2017 at the National Cancer Center Hospital East were investigated. The efficacy of CCPT at the primary site was evaluated via endoscopy; primary complete response (CR) was defined as disappearance of the tumor lesion/ulcer and absence of cancer cells on biopsy. Endoscopic evaluation was performed with the same protocol of conventional chemoradiotherapy. Local recurrence after CCPT was treated with endoscopic resection for cT1a and with esophagectomy or photodynamic therapy for cT1b+. Of the 44 patients (median age, 70 years) that underwent CCPT, 43 patients (98%) achieved primary CR. Among the 44 patients, the 3-year overall survival rate was 95.2%. Five patients (11%) developed local recurrence without regional lymph node or distant metastasis and received endoscopic resection or photodynamic therapy. All five patients were alive with no recurrence after a median 23 months. The results suggest that CCPT is an effective treatment for cT1 ESCC and careful endoscopic follow-up allows preferable local control with salvage endoscopic treatment.

BACKGROUND AND AIM Endoscopic diagnosis of advanced histology in colorectal lesions sized

A randomized phase III trial in Japan commenced in June 2019. The present standard treatment for newly diagnosed glioblastoma is maximal resection followed by chemoradiotherapy with temozolomide. The purpose of this study is to confirm the superiority of maximal resection with carmustine wafer implantation followed by chemoradiotherapy with temozolomide over the standard maximal resection followed by chemoradiotherapy with temozolomide in terms of overall survival for newly diagnosed glioblastoma. A total of 250 patients will be accrued from 35 Japanese institutions in 5.5 years. Patients with >90% surgical resection will be registered and randomly assigned to each group with 1:1 allocation. The primary endpoint is overall survival and the secondary endpoints are progression-free survival, loco-regional progression-free survival and incidence of adverse events. This trial has been registered in the Japan Registry of Clinical Trial, as jRCT1031190035 [https://jrct.niph.go.jp/en-latest-detail/jRCT1031190035].

Objectives Neoadjuvant chemotherapy (nCT) followed by surgery is one of the standard treatments for resectable esophageal squamous cell carcinoma (ESCC). According to the Response Evaluation Criteria in Solid Tumors, endoscopic evaluation of a primary lesion is not recommended during nCT because of reduced objectivity. This study aimed to develop and validate endoscopic evaluation criteria for nCT. Methods This study retrospectively investigated patients with T2/3 ESCC who underwent nCT followed by radical esophagectomy across two institutions (test and validation sets). We retrospectively estimated the therapeutic effect by classifying patients according to degree of tumor shrinkage (evaluated with endoscopy) as follows: marked reduction (MR), half reduction (HR), insufficient reduction (IR), and progressive disease (PD). Three endoscopists evaluated patients in the test set. Another three endoscopists evaluated patients in the validation set. We analyzed recurrence-free survival (RFS) 3 years after surgery. Results Of 129 patients in the test set, 44 had MR, 35 had HR, 44 had IR, and six had PD. The 3-year RFS rates were 55% (overall), 79% (MR), 54% (HR), 35% (IR), and 33% (PD). Of 91 patients in the validation set, 22 had MR, 49 had HR, 18 had IR, and two had PD. The 3-year RFS rates were 54% (overall), 77% (MR), 55% (HR), 22% (IR), and 50% (PD). Conclusions Our endoscopic criteria for nCT predicted prognosis; however, future studies are needed to further investigate our criteria before general application in the clinical setting.

Photodynamic therapy (PDT) using a conventional photosensitizer was approved for esophageal cancer in the early 1990s; however, it was replaced by other conventional treatment modalities in clinical practice because of the high frequency of cutaneous phototoxicity and esophageal stricture after the procedure. The second-generation photosensitizer, talaporfin sodium, which features more rapid clearance from the body, was developed to reduce skin phototoxicity, and talaporfin sodium can be excited at longer-wavelength lights comparing with a conventional photosensitizer. Endoscopic PDT using talaporfin sodium was initially developed for the curative treatment of central-type early lung cancer in Japan, and was approved in the early 2000s. After preclinical experiments, PDT using talaporfin sodium was investigated for patients with local failure after chemoradiotherapy, which was the most serious unmet need in the practice of esophageal cancer. According to the favorable results of a multi-institutional clinical trial, PDT using talaporfin sodium was approved as an endoscopic salvage treatment for patients with local failure after chemoradiotherapy for esophageal cancer. While PDT using talaporfin sodium is gradually spreading in clinical practice, further evaluation at the point of clinical benefit is necessary to determine the importance of PDT in the treatment of esophageal cancer.

178 Background: Recently, JCOG0502 trial have shown a comparable efficacy with chemoradiotherapy (CRT) and esophagectomy as standard treatment in patients with clinical stage (cStage) I esophageal squamous cell carcinoma (ESCC), showing the standard treatment option of CRT. However, there is few reports for comparison of clinical outcomes with these treatments in real-world. The aim of this study was to clarify the real-world outcomes in cStage I ESCC who performed with CRT or esophagectomy. Methods: This retrospective study included patients with clinical stage I ESCC who received thoracoscopic or open esophagectomy with three-field lymph node dissection or CRT mainly consisted of 5-fluorouracil and platinum with concurrent radiotherapy (50.4 Gy/28Fr or 60 Gy/30Fr) between 2009 and 2017 at National Cancer Center Hospital East. Survival outcomes were calculated using the Kaplan-Meier method, and the differences were evaluated using the log-rank test. Results: Among a total of 156 patients, 128 were male and median age was 68 years old. 120 and 36 patients underwent esophagectomy and CRT, respectively. ECOG performance status 0/1/2 were 138/12/6 patients. Tumor location was Ut/Mt/Lt in 16/87/53 patients. Clinical tumor depth (MM-SM1/SM2-SM3) were 33/123 patients. Patients’ characteristics were similar among treatment groups, except clinical tumor depth (SM2-3; 84.2% in esophagectomy group vs. 61.1% in CRT group, p = 0.005). All patients underwent radical surgery in esophagectomy group, while three patients (8.3%) in CRT group were received additional esophagectomy or endoscopic resection due to residual disease. With a median follow-up of 72 months, 5-year overall survival (OS) and progression-free survival rate were 81.5%/77.0% in esophagectomy group and 82.6/74.4% in CRT group (p = 0.89 and p = 0.48). In safety profile, grade 3 or higher stenosis was observed in 21.7% of esophagectomy group. There was no treatment-related death in both groups. In subgroup analysis for OS, elderly patients (75 years and older) tended to have better 5-year OS rate in CRT group (76.9% in esophagectomy group vs. 81.8% in CRT group), while younger patients ( < 75 years) showed comparable 5-year OS rate in both groups (82.4% in esophagectomy group vs. 82.9% in CRT group). Conclusions: Real-world data reproduced the results of clinical trial, supporting CRT as one of the standard treatment options in patients with cStage I ESCC.

TPS257 Background:Parallel-group controlled trial of esophagectomy versus chemoradiotherapy (JCOG0502) showed chemoradiotherapy (CRT) is considered as a standard treatment option for clinical-T1bN0M0 esophageal squamous cell carcinoma (ESCC) with organ preservation. However, locoregional recurrence after CRT occurs in 20% of patients and requires salvage treatment including salvage surgery, chemo(radio)therapy, and endoscopic resection. Salvage treatments can cause complications and treatment-related death. CRT with elective nodal irradiation (ENI) have been reported to reduce the locoregional recurrence of esophageal cancer. We conduct the clinical trial to evaluate the efficacy of modified CRT with ENI compared with CRT without ENI for the patients with cTbN0M0 ESCC. The primary purpose of this study is to investigate whether modified CRT with ENI reduces the locoregional recurrence that cannot be completely resected by salvage endoscopic resection and preserve esophagus without compromising overall survival. Methods:Eligibility criteria include the followings; thoracic ESCC, adenosquamous, or basaloid cell carcinoma with clinical-T1bN0M0, age 20 or older, performance status 0 or 1, adequate organ function, and patient who do not have a preference to receive a surgical resection as an initial therapy. Patients are randomly assigned to following two arms using the minimization method with a random component to balance institution, tumor length (≤4cm versus > 4cm), and age (≤65 years old versus > 65 years old). Patients in arm A receive CRT consisted of CDDP (70 mg/m2/day, days 1 and 29) and 5-FU (700 mg/m2/day, days 1-4 and 29-32, civ) with concurrent radiotherapy (60 Gy/30 fr without ENI). Patients in arm B receive CRT consisted of CDDP (75 mg/m2/day, days 1 and 29) and 5-FU (1000 mg/m2/day, days 1-4 and 29-32, civ) with concurrent radiotherapy (50.4 Gy/ 28 fr with ENI of 41.4 Gy/23 fr). Primary endpoint is major progression-free survival (MPFS), defined as the time from randomization to the date of death or disease progression except achieving curative resection by salvage endoscopic resection. We assumed 5-year MPFS with arm A to be 70% and expected a 10% improvement for arm B. The planned sample size was calculated as a total of 280 patients (140 patients per arm) with a one-sided alpha of 5%, power of 70%, an accrual period of 4 years, and a follow-up period of 5 years. This trial was activated in July 2020. The study was also registered at the Japan Registry of Clinical Trials (jRCT) as study number jRCTs031200067. Clinical trial information: jRCTs031200067.

4565 Background: Esophageal squamous cell carcinoma (ESCC) is associated with synchronous or metachronous cancer at other primary sites. Previous studies have suggested that patients (pts) with ESCC are still at a high risk of second primary malignancies after definitive therapies. In particular, early-stage ESCCs result in good prognosis, which is associated with a higher risk of second primary malignancies. Methods: The JCOG0502 was a phase III trial, which included a randomized and a non-randomized part and compared esophagectomy with definitive chemoradiotherapy in clinical T1bN0 ESCC. We additionally reviewed data of all pts enrolled in the JCOG0502 for second primary malignancies. Lugol-voiding lesions (LVLs) were assessed in the noncancerous esophageal mucosa before the treatments. Results: Among 379 enrolled pts, 213 pts received esophagectomy and the remaining received chemoradiotherapy. Patient characteristics of overall cohort were as follows: male, 85%; median age, 63 (range, 41–75) years; upper- /middle- /lower thoracic esophagus, 11/63/27%; alcohol consumption history, 79%; smoking history, 66%; prevalence of no LVLs/several LVLs/many LVLs/unknown, 45/36/8/11%. With a median follow-up of 7.1 years, a total of 118 second malignancies were observed in 99 pts (26%). Cumulative incidences of second malignancies after 3, 5, 10 years were 9, 15, 36%, respectively. Most common primary tumor sites were head and neck (35%), followed by stomach (20%) and lung (14%). In multivariable analyses, several LVLs [hazard ratio (HR): 2.24, 95% confidential interval (CI): 1.32–3.81, vs. no LVLs] and many LVLs (HR: 2.88, 95% CI: 1.27–6.52, vs. no LVLs) were significantly associated with the development of second malignancies. Regarding the three most common types of cancers, 62 out of the 77 cancers (81%) were diagnosed in clinical stage 0–I. Seventeen pts died due to second primary malignancies. There were 4 and 3 deaths from head and neck and lung cancer, respectively. Whereas, mortality caused by stomach cancer was not observed. Conclusions: In the JCOG0502, the incidence of second malignancies was high, indicating that careful follow-up is required for ESCC pts even after treatment completion. The presence of LVLs in esophagus was identified as an independent predictive factor for second primary malignancies, which may be useful for surveillance strategies. Clinical trial information: UMIN000000551 .

TPS457 Background: Near Infrared Photoimmunotherapy (NIR-PIT) is a newly developed, molecular targeted cancer therapy based on conjugating a near infrared silica-phthalocyanine dye to a monoclonal antibody, which result in necrotic cell death of targeted cancer cell immediately after exposure to near infrared light. Phase IIa trial of NIR-PIT with RM-1929 (anti-EGFR antibody cetuximab conjugated to IRDye 700DX) showed a 43% objective response rate (ORR) for recurrent head and neck squamous cell carcinoma (Cognetti DM, et al.ASCO 2019 abstr 6014). Meanwhile, PD-1 blockade reverses adaptive immune resistance, resulting in activation of tumor infiltrating lymphocyte after NIR-PIT in syngeneic mouse models (Nagaya T, et al. Cancer immunology research. 2019). The objective of this study is to investigate the safety and efficacy of the NIR-PIT using ASP-1929 (analogous to RM-1929) in combination with nivolumab for advanced gastric or esophageal cancer. Methods: The study is an open-label, single-arm, single-center, Phase Ib clinical trial. Eligible patients are with unresectable esophagogastric squamous cell carcinoma or EGFR positive adenocarcinoma after standard chemotherapy. Dose escalation cohort is designed to determine the recommended dose of laser irradiation energy density in a “3+3” design (50, 75, and 100 J/cm2). Nivolumab of 240 mg on Day 1 and ASP-1929 of 640 mg/m2 on Day 8 is administered, and laser irradiation is performed under endoscopy using the laser PIT unit on Day 9. In expansion cohort, approximately 20 patients will be enrolled. The primary endpoint is proportion of incidence of dose-limiting toxicity, and the secondary endpoints are proportion of incidence of adverse events, ORR, local complete response rate, progression-free survival (PFS), local PFS, overall survival, and proportion of incidence of device malfunction. We also investigate several biomarkers using pre- and post-treatment biopsied samples. First patient will be enrolled in December 2019. Clinical trial information: JapicCTI-194969.

TPS263 Background: Local recurrence is one of the most common forms of recurrence after curative resection for primary rectal cancer. Surgical resection is recommended for locally recurrent rectal cancer (LRRC) to achieve radical cure if the tumor is judged as resectable with negative margins. However, a high local re-recurrent risk after surgery is a major problem due to the difficulty of re-resection and the serious symptoms, such as pain or fistula, resulting from re-recurrence. Preoperative chemoradiotherapy (preCRT) is expected to improve local control after radical surgery for radiation naïve LRRC; however, high frequency of surgical complications after preCRT cannot be ignored. Due to the refractory nature and rarity of LRRC, the true impact of preCRT on oncological and surgical outcomes has not been clarified by clinical trials. The purpose of this study is to confirm the superiority of preCRT followed by surgery plus adjuvant chemotherapy over surgery plus adjuvant chemotherapy alone, in terms of local relapse-free survival for resectable LRRC. Methods: Eligibility criteria include resectable LRRC without distant metastasis, no prior pelvic irradiation, no prior surgery for LRRC, aged 20-80 years, and sufficient organ function. Eligible patients are randomized into the surgery and adjuvant chemotherapy (arm A) or preCRT followed by surgery and adjuvant chemotherapy (arm B). PreCRT consists of the standard dose of capecitabine and radiotherapy (50.4Gy). Adjuvant chemotherapy consists of mFOLFOX6, CAPOX, capecitabine, or 5FU+l-LV. The primary endpoint is local relapse-free survival (LRFS), and the secondary endpoints include overall survival, relapse-free survival, %R0 resection, incidence of adverse events, and quality of life after surgery. The 3-year LRFS of arm A is assumed to be 60% with a 13% increase expected in arm B. The sample size was calculated as 106 (53 per arm) with a one-sided alpha of 10%, power of 70%, and accrual period of 6 years. This trial was initiated on 19 August 2019. Clinical trial information: jRCTs031190076.

Standard therapy for gastric diffuse large B‐cell lymphoma (DLBCL) is considered to be chemotherapy with or without involved‐field radiation therapy. Although R‐CHOP therapy alone is widely used for DLBCL with gastric lesions (DLBCL‐GL), the outcome and incidence of treatment‐related gastric complications following R‐CHOP are not well known. This study aimed to evaluate the outcome after R‐CHOP therapy in patients with gastric DLBCL including gastric complications and to identify risk factors for the complications. Consecutive patients with newly diagnosed DLBCL‐GL treated with R‐CHOP between 2003 and 2014 were retrospectively evaluated. DLBCL‐GL was defined only when pathologically confirmed in the stomach. Of the 96 patients with DLBCL‐GL, 63 patients were diagnosed with gastric symptoms. Eighty‐eight patients (92%) completed six to eight cycles of R‐CHOP. The complete remission (CR) rate was 86%, and 3‐year and 5‐year overall survival rates were 80% and 73%, respectively. Patients were well stratified according to the Revised International Prognostic Index (R‐IPI). Complication rate was 8% (8/96); seven patients had bleeding and three had stenosis. No patients had gastric perforation. Bleeding occurred during the first cycle of R‐CHOP in five patients (5/7, 71%). Patients with gastric complications had a lower R‐CHOP completion rate (50%, P = 0.001) and a lower CR rate (25%, P

Background and objectives To clarify prognostic factors for the patients with esophageal squamous cell carcinoma (ESCC) through an assessment of surgically resected specimens modified by neoadjuvant chemotherapy (nCT). Methods We retrospectively reviewed the clinicopathological data of 143 consecutive patients with ESCC who underwent nCT followed by surgery between 2008 and 2012 at our institution and conducted survival analysis. The tumor regression grade (TRG) was classified based on the proportion of residual tumor cells in the area where the tumor was thought to have existed before nCT as follows: Grade 0 (no therapeutic effect), Grade 1a (residual tumor cells ≥2/3), Grade 1b (1/3≤ residual tumor cells

Primary adenocarcinoma arising from heterotopic gastric mucosa (HGM) is rare and the clinicopathological characteristics are not well known. We present two cases of esophageal adenocarcinoma arising from HGM with a review of a case series. Case 1 was a 78-year-old woman who underwent a periodic medical examination without complaining of any symptoms. Preoperative evaluation suggested esophageal adenocarcinoma arising from the HGM. The patient was treated with endoscopic submucosal dissection. Definitive pathological diagnosis confirmed adenocarcinoma arising from the HGM. Case 2 was a 70-year-old man who underwent a medical examination after complaining of dysphagia. Preoperative diagnosis suggested esophageal adenocarcinoma; however, its origin was unclear. The patient was treated with surgical resection. Definitive pathological diagnosis revealed adenocarcinoma arising from the HGM. In this article, the authors report the clinicopathological features of esophageal adenocarcinoma arising from HGM that were collected from a literature review and our cases.

Objectives Lymph node metastasis (LNM) in submucosal invasive esophageal squamous cell carcinoma (SM-ESCC) is a prognostic factor. The aim of this study was to identify a histopathologic predictor of LNM in SM-ESCC. Methods In total, 108 patients who underwent an esophagectomy and lymph node dissection without preoperative therapy and who were pathologically diagnosed with SM-ESCC were enrolled in this study. Relationships between several clinicopathologic factors and LNM were examined. Results A multivariate analysis revealed that a tumor size of 35 mm or more (P = .0025), submucosal invasive depth (SID) of 2,000 μm or more (P = .013), and lymphatic infiltration (P < .0001) were significant independent predictors of LNM. In addition, there were significant differences in recurrence-free survival curves between patients with SID less than 2,000 μm or not (P = .029) and tumor size less than 35 mm or not (P = .049). Conclusions This study suggests that SID may predict not only LNM but also poor prognosis.

Background Although several studies suggested that immune checkpoint inhibitors may enhance an efficacy of radiotherapy (RT), it remains unclear in patients (pts) with advanced gastric cancer (AGC). Methods Total 34 AGC pts treated with RT for the primary gastric lesion from April 2013 to March 2019 were analyzed in this study. Pts were divided into two groups according to whether they had received nivolumab before RT or not. Primary tumor responses were assessed according to volumetry on CT scan with tumor response as > 70% decrease in tumor volume. Endoscopic responses were evaluated in pts who underwent endoscopy after RT. Tumor infiltrating lymphocytes (TILs) were also analyzed to examine the tumor microenvironmental immune status in the pts. Results Among 34 pts, 16 pts had received nivolumab before RT. There were no significant differences in baseline characteristics between nivolumab-exposed and nivolumab-naive groups. 70% tumor reductions by RT were observed in 25% (4/16) in nivolumab-exposed group but no patients (0/18) in nivolumab-naive group (P = 0.039). Among pts who received endoscopy after RT, four of seven pts in nivolumab-exposed group experienced partial response, while no response was observed among 10 nivolumab-naive pts (P = 0.015). TILs were evaluated in pts whose tumor samples were available. CD8+ T cells/effector regulatory T cells (eTreg cells) ratio in TILs was markedly increased after nivolumab in pts who achieved response, but not observed in pts who had no tumor reduction. A significant increase of CD8+ T cells/eTreg cells ratio after nivolumab treatment was observed in nivolumab-exposed pts (n = 15), whereas such a tendency was not observed in nivolumab-naive pts (n = 10). Conclusions RT to primary gastric cancer significantly led to tumor response in nivolumab-exposed pts compared with nivolumab-naive pts. Immune profiling suggested that nivolumab might enhance the sensitivity to RT by immunoactivation via increasing CD8+ T cell/eTreg cell ratio.

301 Background: S-1 is an oral agent consisting of a mixture of tegafur which is a prodrug of 5-fluorouracil (5-FU), 5-chloro-2,4-dihydroxypyrimidine (DHP) and potassium oxonate. Serum concentration of 5-FU increases in case of renal dysfunction due to decrease of DHP excretion into urine. The aim of this study was to evaluate the influence of renal function to the efficacy and safety of S-1 with concurrent radiotherapy (RT) for locally advanced pancreatic cancer (LAPC). Methods: This study was an integrated exploratory analysis of JCOG1106 and LAPC- S1RT, in which pts with LAPC received RT (50.4Gy/28 fr over 5.5 weeks) and concurrent S-1 (40 mg/m2/dose, bid. on the day of irradiation). Eligibility criteria for this study were pts who received both irradiation and S-1 at least once without induction chemotherapy, and who had creatinine clearance (CCr) ≥ 50 ml/min at the time of registration. We assigned pts into high (≥ 80 ml/min) and low (< 80 ml/min) CCr groups. The primary endpoint was the incidence of ≥ Grade 3 adverse reactions (ARs). Secondary endpoints were the incidence of ≥ Grade 2 gastrointestinal ARs (GI-ARs) defined as anorexia, nausea, vomiting, diarrhea and mucositis oral, relative dose intensity of S-1, CA19-9 response, progression-free survival, and overall survival. Results: Fifty and 59 pts were included in this study from JCOG1106 and LAPC-S1RT, respectively. Median age was 65 years old (range: 31–80), and 57 pts were male. Median CCr was 80.4 ml/min. High CCr group included 57 pts and the median was 97.5 ml/min (range 80.0–194.6), and low CCr group included 52 pts and the median was 64.4 ml/min (range 50.0–78.3). Low CCr group tended to have more ≥ Grade 3 ARs and ≥ Grade 2 GI-ARs compared to high CCr group (30.8% vs. 15.8% and 51.9% vs. 36.8%). However, no evident tendencies were observed in other secondary endpoints. Multivariable analysis showed risk ratio of low CCr group for ≥ G3 ARs was 1.493 [95% CI: 0.710–3.145], although risk ratio of females was 2.486 [95% CI: 1.043–5.924]. Conclusions: Our study indicated that renal dysfunction may increase adverse reactions in the treatment of S-1 with concurrent RT for LAPC, and we should pay attention to renal function and consider for dose reduction.

Background and study aims: One of the major complications after endoscopic resection (ER) for large superficial esophageal squamous cell carcinoma (ESCC) is benign esophageal stricture, which can reduce quality of life even if ESCC achieves a cure without organ resection. Recently, steroid administration has been reported as a prophylactic treatment to prevent esophageal strictures. This retrospective study evaluated the stricture rate according to the different width of mucosal defects due to ER and compared it to that seen with prophylactic steroid administration. Patients and methods: Between June 2007 and December 2013, we enrolled patients with ESCC who had 3/4 or larger circumferential mucosal defects due to ER. In December 2009, steroid injections (triamcinolone acetonide 50 mg) into the ulcer bed due to ER were introduced. Beginning in November 2012, we commenced oral steroid administration (prednisolone 30 mg/day, tapered gradually for 8 weeks) in addition to steroid injection. Patients were classified into 3 groups according to the width of mucosal defect after ER (Group A, ≥ 3/4 and