Japanese Society of Medical Oncology clinical guidelines: Molecular testing for colorectal cancer treatment, 5th edition.

Molecular testing to determine optimal therapies is essential for managing patients with colorectal cancer (CRC). In October 2022, the Japanese Society of Medical Oncology published the 5th edition of the Molecular Testing Guideline for Colorectal Cancer Treatment. In this guideline, in patients with unresectable CRC, RAS/BRAF V600E mutational and mismatch repair tests are strongly recommended prior to first-line chemotherapy to select optimal first- and second-line therapies. In addition, HER2 testing is strongly recommended because the pertuzumab plus trastuzumab combination is insured after fluoropyrimidine, oxaliplatin, and irinotecan in Japan. Circulating tumor DNA (ctDNA)-based RAS testing is also strongly recommended to assess the indications for the readministration of anti-EGFR antibodies. Both tissue- and ctDNA-based comprehensive genomic profiling tests are strongly recommended to assess the indications for targeted molecular drugs, although they are currently insured in patients with disease progression after receiving standard chemotherapy (or in whom disease progression is expected in the near future). Mutational and mismatch repair testing is strongly recommended for patients with resectable CRC, and RAS/BRAF V600E mutation testing is recommended to estimate the risk of recurrence. Mutational and mismatch repair and BRAF testing are also strongly recommended for screening for Lynch syndrome. Circulating tumor DNA-based minimal residual disease (MRD) testing is strongly recommended for estimating the risk of recurrence based on clinical evidence, although MRD testing was not approved in Japan at the time of the publication of this guideline.

Whole-transcriptome sequencing in advanced gastric or gastroesophageal cancer: A deep dive into its clinical potential.

Advanced gastric and gastroesophageal junction cancers (GC/GEJCs) harbor diverse molecular signatures, highlighting the need for intricate evaluations to identify potential therapeutic targets. Although whole-transcriptome sequencing (WTS) has emerged as a useful tool for understanding these molecular intricacies, its clinical implications have yet to be fully elucidated. This study evaluated the correlation between immunohistochemistry (IHC) and WTS, compared their clinical significance, and identified potential therapeutic targets undetectable through IHC alone. We enrolled 140 patients with advanced GC/GEJC and assessed them using IHC for six pivotal biomarkers: claudin-18 (CLDN18), human epidermal growth factor receptor 2 (HER2), multiple receptor tyrosine kinases (RTKs), and programmed death ligand 1 (PD-L1). Concurrently, WTS was employed as part of the analyses in MONSTAR-SCREEN-2, a multicenter multiomics study. IHC analysis revealed 16.4% HER2, 39.3% CLDN18 (2+/3 + ≥75%), and 15.8% PD-L1 (combined positive score ≥ 10) positivity, among other molecular markers. Significant correlations were observed between IHC and WTS for all six pivotal biomarkers. Among nineteen HER2 IHC-positive patients treated with anti-HER2 therapeutics, ERBB2 status in WTS was significantly associated with progression-free survival (ERBB2-high vs. -low: median 9.0 vs. 5.6 months, log-rank p = 0.046). IHC-based molecular profiling revealed significantly high expression of CLDN18 in RTK-negative patients, with 78.4% positive for either CLDN18 or PD-L1. Additionally, WTS revealed elevated expression of pivotal biomarkers in patients displaying negative targetable biomarkers via IHC. Our findings highlighted the significant correlation between IHC and WTS, reinforcing the clinical utility of WTS. A subset with IHC-negative but WTS-positive status may benefit from specific biomarker-targeted therapies.

Prognostic and predictive factors for the efficacy and safety of trastuzumab deruxtecan in HER2-positive gastric or gastroesophageal junction cancer.

BACKGROUND: Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate targeting HER2-positive gastric cancer or gastroesophageal junction cancer (GC/GEJC). Although effective, T-DXd has notable toxicities, including interstitial lung disease (ILD). This study evaluated the efficacy, safety, and prognostic factors associated with T-DXd for GC/GEJC. METHODS: A retrospective observational study was conducted at our institution by reviewing medical records of patients treated with T-DXd until September 2023. Eligible patients had unresectable advanced or recurrent GC/GEJC, HER2 status of IHC 3 + or IHC 2 + /ISH-positive, and prior treatment with trastuzumab-containing regimen. RESULTS: Among the 101 patients analyzed, the initial T-DXd dose was 6.4 mg/kg in 77 patients and 5.4 mg/kg in 24 patients. The objective response rate was 54.3%, with a median PFS of 5.4 months and a median OS of 11.4 months. The significant prognostic factors for shorter PFS and OS included ECOG PS ≥ 1, presence of primary lesion, and peritoneal metastasis but not the initial T-DXd dose. ILD occurred in 14.9% of patients. Notably, higher T-DXd dose and smaller tumor burden were associated with a higher incidence of ILD. CONCLUSIONS: Several factors were associated with prognosis after T-DXd treatment in patients with GC/GEJC. Tumor burden is a potential risk factor for T-DXd-related ILD. Further studies are needed to optimize dosing based on tumor burden and to improve the therapeutic index.

Efficacy and safety of trifluridine/tipiracil plus ramucirumab in comparison with trifluridine/tipiracil monotherapy for patients with advanced gastric cancer-single institutional experience.

BACKGROUND: Trifluridine/tipiracil plus VEGF inhibition with ramucirumab (RAM) for advanced gastric cancer (AGC) demonstrated clinical activity with an acceptable toxicity profile in previous phase II trial. However, little is known about its efficacy and safety in clinical practice in comparison with trifluridine/tipiracil monotherapy. METHODS: We retrospectively investigated efficacy and safety of trifluridine/tipiracil plus RAM and trifluridine/tipiracil monotherapy as third or later line treatment for AGC patients. RESULTS: Forty-one patients receiving trifluridine/tipiracil plus RAM and 60 patients receiving trifluridine/tipiracil monotherapy were analyzed. The objective response rate (ORR) and the disease control rate (DCR) were 13.5% and 64.9% in the trifluridine/tipiracil plus RAM group, and 3.8% and 42.3% in the trifluridine/tipiracil monotherapy group, respectively (ORR; P = 0.122, DCR; P = 0.052). The median progression-free survival (PFS) and the median overall survival (OS) were 3.0 months and 7.2 months in the trifluridine/tipiracil plus RAM group, and 1.8 months and 3.8 months in the trifluridine/tipiracil monotherapy group, respectively (HR for PFS = 0.66; P = 0.059, HR for OS = 0.50; P = 0.007). Multivariate analysis showed significantly longer PFS (HR = 0.52; P = 0.011) and OS (HR = 0.51; P = 0.031) in the trifluridine/tipiracil plus RAM group compared to the trifluridine/tipiracil monotherapy group. No unexpected adverse events were observed in both groups. CONCLUSIONS: Trifluridine/tipiracil plus RAM might show favorable anti-tumor activity with an acceptable toxicity profile in comparison with trifluridine/tipiracil monotherapy, suggesting one treatment option for AGC patients in salvage line. The combination needs further evaluation in ongoing randomized trials.

Japanese Society of Medical Oncology/Japan Society of Clinical Oncology/Japanese Society of Pediatric Hematology/Oncology-led clinical recommendations on the diagnosis and use of immunotherapy in patients with DNA mismatch repair deficient (dMMR) tumors, third edition.

BACKGROUND: Clinical trials have reported the efficacy of immune checkpoint inhibitors in the treatment of mismatch repair-deficient (dMMR) advanced solid tumors. The accumulated evidence of tumor agnostic agent has been made since PD-1 inhibitor was approved and used in clinical practice. Therefore, we have revised the guideline "Japan Society of Clinical Oncology provisional clinical opinion for the diagnosis and use of immunotherapy in patients with deficient DNA mismatch repair tumors, cooperated by Japanese Society of Medical Oncology, First Edition". METHODS: Clinical questions regarding medical care were formulated for patients with dMMR advanced solid tumors. Relevant publications were searched by PubMed and Cochrane Database. Critical publications and conference reports were added manually. Systematic reviews were performed for each clinical question for the purpose of developing clinical recommendations. The committee members identified by Japan Society of Clinical Oncology (JSCO), Japanese Society of Medical Oncology (JSMO), and Japanese society of pediatric hematology/oncology (JSPHO) voted to determine the level of each recommendation considering the strength of evidence, expected risks and benefits to patients, and other related factors. Thereafter, a peer review by experts nominated from JSCO, JSMO, and JSPHO and the public comments among all societies' members were done. RESULTS: The current guideline describes two clinical questions and eight recommendations for whom, when, and how MMR status should be tested. CONCLUSION: In this guideline, the committee proposed eight recommendations for performing MMR testing properly to select patients who are likely to benefit from immunotherapy.

Japanese Society of Medical Oncology/Japan Society of Clinical Oncology/Japanese Society of Pediatric Hematology/Oncology-led clinical recommendations on the diagnosis and use of tropomyosin receptor kinase inhibitors in adult and pediatric patients with neurotrophic receptor tyrosine kinase fusion-positive advanced solid tumors.

BACKGROUND: Clinical trials have reported the efficacy of tropomyosin receptor kinase (TRK) inhibitors against neurotrophic receptor tyrosine kinase (NTRK) fusion gene-positive advanced solid tumors. The accumulated evidence of tumor-agnostic agent has made since TRK inhibitors were approved and used in clinical practice. Therefore, we have revised the 'Japan Society of Clinical Oncology (JSCO)/Japanese Society of Medical Oncology (JSMO)-led clinical recommendations on the diagnosis and use of tropomyosin receptor kinase inhibitors in adult and pediatric patients with neurotrophic receptor tyrosine kinase fusion-positive advanced solid tumors, cooperated by the Japanese Society of Pediatric Hematology/Oncology (JSPHO)'. METHODS: Clinical questions regarding medical care were formulated for patients with NTRK fusion-positive advanced solid tumors. Relevant publications were searched by PubMed and Cochrane Database. Critical publications and conference reports were added manually. Systematic reviews were performed for each clinical question for the purpose of developing clinical recommendations. The committee members identified by JSCO, JSMO, and JSPHO voted to determine the level of each recommendation considering the strength of evidence, expected risks and benefits to patients, and other related factors. Thereafter, a peer review by experts nominated from JSCO, JSMO, and JSPHO, and the public comments among all societies' members was done. RESULTS: The current guideline describes 3 clinical questions and 14 recommendations for whom, when, and how NTRK fusion should be tested, and what is recommended for patients with NTRK fusion-positive advanced solid tumors. CONCLUSION: The committee proposed 14 recommendations for performing NTRK testing properly to select patients who are likely to benefit from TRK inhibitors.

Japanese Society of Medical Oncology/Japan Society of Clinical Oncology/Japanese Society of Pediatric Hematology/Oncology-led clinical recommendations on the diagnosis and use of immunotherapy in patients with high tumor mutational burden tumors.

The development of novel antitumor agents and accompanying biomarkers has improved survival across several tumor types. Previously, we developed recommendations for tumor-agnostic treatments in patients with solid tumors with DNA mismatch repair deficient or neurotrophic receptor tyrosine kinase fusions. Recently, immune checkpoint inhibitors have shown efficacy in patient with tumor mutation burden-high (TMB-H) solid tumors and have been established as a third tumor-agnostic agent, making it necessary to develop the guideline prioritized for these patients. Clinical questions regarding medical care were formulated for patients with TMB-H advanced solid tumors. Relevant publications were searched by PubMed and Cochrane Database. Critical publications and conference reports were added manually. Systematic reviews were performed for each clinical question for the purpose of developing clinical recommendations. The committee members identified by Japan Society of Clinical Oncology (JSCO), Japanese Society of Medical Oncology (JSMO), and Japanese society of pediatric hematology/oncology (JSPHO) voted to determine the level of each recommendation considering the strength of evidence, expected risks and benefits to patients, and other related factors. Thereafter, a peer review by experts nominated from JSCO, JSMO, and JSPHO, and the public comments among all societies' members was done. The current guideline describes three clinical questions and seven recommendations for whom, when, and how TMB should be tested, and what is recommended for patients with TMB-H advanced solid tumors. In this guideline, the committee proposed seven recommendations for performing TMB testing properly to select patients who are likely to benefit from immunotherapy.

Complete response to definitive chemoradiotherapy in unresectable locally advanced esophageal squamous cell carcinoma.

BACKGROUND: Although definitive chemoradiotherapy (CRT) is the standard therapy for patients with unresectable locally advanced esophageal squamous cell carcinoma (ESCC), poor survival has been reported. Although the complete response (CR) rate is strongly correlated with good prognosis, the predictive factors for CR have not been elucidated. METHODS: This registry study aimed to identify predictors of CR to definitive CRT in patients with unresectable locally advanced ESCC. "Unresectable" was defined as the primary lesion invading unresectable adjacent structures such as the aorta, vertebral body, and trachea (T4b), or the regional and/or supraclavicular lymph nodes invading unresectable adjacent structures (LNT4b). RESULTS: Overall, 175 patients who started definitive CRT between January 2013 and March 2020 were included. The confirmed CR (cCR) rate was 24% (42/175). The 2-year progression-free survival (PFS) and overall survival (OS) rates of cCR cases vs. non-cCR cases were 59% vs. 2% (log-rank p < 0.001) and 90% vs. 31% (log-rank p < 0.001), with a median follow-up period of 18.5 and 40.5 months, respectively. Multivariate analysis of clinicopathological factors revealed that tumor length ≥ 6 cm [odds ratio (OR) 0.446; 95% CI 0.220-0.905; p = 0.025] was a predictor of cCR. CONCLUSIONS: Favorable PFS and OS rates were observed in patients with cCR. Tumor length was a predictive factor for cCR.

DENEB: Development of new criteria for curability after local excision of pathological T1 colorectal cancer using liquid biopsy.

According to the current international guidelines, high-risk patients diagnosed with pathological T1 (pT1) colorectal cancer (CRC) who underwent complete local resection but may have risk of developing lymph node metastasis (LNM) are recommended additional intestinal resection with lymph node dissection. However, around 90% of the patients without LNM are exposed to the risk of being overtreated due to the insufficient pathological criteria for risk stratification of LNM. Circulating tumor DNA (ctDNA) is a noninvasive biomarker for molecular residual disease and relapse detection after treatments including surgical and endoscopic resection of solid tumors. The CIRCULATE-Japan project includes a large-scale patient-screening registry of the GALAXY study to track ctDNA status of patients with stage II to IV or recurrent CRC that can be completely resected. Based on the CIRCULATE-Japan platform, we launched DENEB, a new prospective study, within the GALAXY study for patients with pT1 CRC who underwent complete local resection and were scheduled for additional intestinal resection with lymph node dissection based on the standard pathologic risk stratification criteria for LNM. The aim of this study is to explore the ability of predicting LNM using ctDNA analysis compared with the standard pathological criteria. The ctDNA assay will build new evidence to establish a noninvasive personalized diagnosis in patients, which will facilitate tailored/optimal treatment strategies for CRC patients.

Definitive chemoradiotherapy has comparable survival outcomes to esophagectomy in patients with clinical T1N0M0 esophageal squamous cell carcinoma: real-world data.

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.

Characteristics and clinical outcomes of patients with advanced gastric or gastroesophageal cancer treated in and out of randomized clinical trials of first-line immune checkpoint inhibitors.

BACKGROUND: Although several randomized trials (RCTs) showed survival benefits of immune checkpoint inhibitor (ICI) plus first-line chemotherapy for advanced gastric or gastroesophageal cancer (AGC), these trials could enroll patients who fulfilled the strict eligibility criteria or waited for certain screening period for central assessment of PD-L1 status. METHODS: We retrospectively compared characteristics and clinical outcomes of the patients with AGC who received first-line chemotherapy in control arm of RCTs with ICIs (control group) or clinical practice (practice group) at our institution from February 2016 to April 2019. RESULTS: The control group had a better baseline Eastern Cooperative Oncology Group performance status (PS0, 81.2% vs. 51.4%, p < 0.001) and a longer interval from first visit to first-line chemotherapy initiation (19 days vs. 9 days, p < 0.001) than the practice group. Median overall survival (OS) was 20.3 months in control group and 15.7 months in practice group, with a trend of longer OS in control group than that in practice group (hazard ratio, 0.71; p = 0.062). More patients in control group were treated with subsequent chemotherapy including ICIs. CONCLUSION: Patients with AGC in RCTs of ICIs had a better PS or a higher chance to receive subsequent chemotherapy, resulting in a better prognosis than those treated in clinical practice. This information should be considered when interpreting RCT results and applying new treatments into clinical practice.

Long-term clinical outcomes of patients diagnosed with pT1a-muscularis mucosae with lymphovascular invasion or pT1b after endoscopic resection for cT1N0M0 esophageal squamous cell carcinoma.

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

CIRCULATE-Japan: Circulating tumor DNA-guided adaptive platform trials to refine adjuvant therapy for colorectal cancer.

Adjuvant chemotherapy has reduced the risk of tumor recurrence and improved survival in patients with resected colorectal cancer. Potential utility of circulating tumor DNA (ctDNA) prior to and post surgery has been reported across various solid tumors. We initiated a new type of adaptive platform trials to evaluate the clinical benefits of ctDNA analysis and refine precision adjuvant therapy for resectable colorectal cancer, named CIRCULATE-Japan including three clinical trials. The GALAXY study is a prospectively conducted large-scale registry designed to monitor ctDNA for patients with clinical stage II to IV or recurrent colorectal cancer who can undergo complete surgical resection. The VEGA trial is a randomized phase III study designed to test whether postoperative surgery alone is noninferior to the standard therapy with capecitabine plus oxaliplatin for 3 months in patients with high-risk stage II or low-risk stage III colon cancer if ctDNA status is negative at week 4 after curative surgery in the GALAXY study. The ALTAIR trial is a double-blind, phase III study designed to establish the superiority of trifluridine/tipiracil as compared with placebo in patients with resected colorectal cancer who show circulating tumor-positive status in the GALAXY study. Therefore, CIRCULATE-Japan encompasses both "de-escalation" and "escalation" trials for ctDNA-negative and -positive patients, respectively, and helps to answer whether measuring ctDNA postoperatively has prognostic and/or predictive value. Our ctDNA-guided adaptive platform trials will accelerate clinical development toward further precision oncology in the field of adjuvant therapy. Analysis of ctDNA status could be utilized as a predictor of risk stratification for recurrence and to monitor the effectiveness of adjuvant chemotherapy. ctDNA is a promising, noninvasive tumor biomarker that can aid in tumor monitoring throughout disease management.

Infusion-related reaction to ramucirumab plus FOLFIRI in patients with advanced colorectal cancer.

BACKGROUND: An infusion-related reaction (IRR) is a well-known adverse event related to monoclonal antibodies, and antihistamine premedication is recommended to prevent IRRs. Ramucirumab plus FOLFIRI therapy is the standard second-line treatment for metastatic colorectal cancer (CRC). Ramucirumab is a fully human antibody, suggesting that the incidence of IRRs is lower, however, the current recommendation for the proper use of ramucirumab is antihistamine premedication, but the incidence and severity of ramucirumab-induced IRR without antihistamine premedication have not been elucidated. METHODS: A retrospective study to evaluate the incidence of ramucirumab-induced IRRs in unresectable CRC patients treated by ramucirumab plus FOLFIRI therapy. If the incidence of IRR without antihistamine premedication was not higher than that of cetuximab in a previous report (5.7%), planning a prospective study was considered. RESULTS: A total of 147 patients with unresectable CRC who had been treated by ramucirumab plus FOLFIRI therapy were identified. Of them, 106 (72%) patients received intravenous antihistamine premedication. An IRR occurred in 2 patients (1.4%), 1 grade 2 and 1 grade 3. They received antihistamine and steroid premedication. On the other hand, IRRs were not observed in 41 patients without antihistamine premedication, and the incidence of IRRs was significantly lower compared with the previous report of cetuximab (p < 0.001). CONCLUSION: The incidence of ramucirumab-induced IRRs without antihistamine premedication is low. Not using antihistamine premedication can decrease medical costs. These findings warrant further investigation in large-scale cohorts to clarify the incidence and severity of ramucirumab-induced IRRs and further clarify the proper use of ramucirumab.

Enhanced tumor response to radiotherapy after PD-1 blockade in metastatic gastric cancer.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. naïve 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-naïve 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. CONCLUSIONS: 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.

Japan Society of Clinical Oncology provisional clinical opinion for the diagnosis and use of immunotherapy in patients with deficient DNA mismatch repair tumors, cooperated by Japanese Society of Medical Oncology, First Edition.

BACKGROUND: Novel therapeutic agents have improved survival outcomes in patients with advanced solid tumors. In parallel, the development of predictive biomarkers to identify patients who are likely to benefit from a certain treatment has also contributed to the improvement of survival. Recently, clinical trials have reported the efficacy of immune checkpoint inhibitors in the treatment of mismatch repair-deficient (dMMR) advanced solid tumors. In Japan, a PD-1 inhibitor for dMMR advanced solid tumors, regardless of the primary tumor site, has been approved. However, there are some issues related to administering immune checkpoint inhibitors in the clinical practice setting, making it necessary to develop the guidelines. METHODS: Clinical questions (CQs) regarding medical care were formulated for patients with dMMR advanced solid tumors, and evidence to the CQs was collected by manual search to prepare recommendations. Then, the committee members voted to determine the level of each recommendation considering the strength of evidence, expected risks and benefits to patients, and other factors. RESULTS: The current guideline, which we consider a provisional clinical opinion at this point, describes the 11 requirements to be considered in terms of patients for whom dMMR testing is recommended, the timing and methods of dMMR testing, and clinical care systems required to perform dMMR testing properly and to administer immune checkpoint inhibitors safely. CONCLUSION: This provisional clinical opinion proposes the requirements for performing dMMR testing properly to select patients who are likely to benefit from immune checkpoint inhibitors and administering them safely.

Japan society of clinical oncology/Japanese society of medical oncology-led clinical recommendations on the diagnosis and use of tropomyosin receptor kinase inhibitors in adult and pediatric patients with neurotrophic receptor tyrosine kinase fusion-positive advanced solid tumors, cooperated by the Japanese society of pediatric hematology/oncology.

BACKGROUND: The development of novel antitumor agents and accompanying biomarkers has improved survival across several tumor types. Previously, we published provisional clinical opinion for the diagnosis and use of immunotherapy in patients with deficient DNA mismatch repair tumors. Recently, efficacy of tropomyosin receptor kinase inhibitors against neurotrophic receptor tyrosine kinase (NTRK) fusion gene-positive advanced solid tumors have been established as the second tumor-agnostic treatment, making it necessary to develop the guideline prioritized for these patients. METHODS: Clinical questions regarding medical care were formulated for patients with NTRK-positive advanced solid tumors. Relevant publications were searched by PubMed and Cochrane Database. Critical publications and conference reports were added manually. Systematic reviews were performed for each clinical question for the purpose of developing clinical recommendations. The committee members identified by Japan Society of Clinical Oncology (JSCO) and Japanese Society of Medical Oncology (JSMO) voted to determine the level of each recommendation considering the strength of evidence, expected risks and benefits to patients, and other related factors. Thereafter, a peer review by experts nominated from JSCO, JSMO, and Japanese Society of Pediatric Hematology/Oncology, and the public comments among all Societies' members was done. RESULTS: The current guideline describes 3 clinical questions and 15 recommendations for whom, when, and how NTRK fusion should be tested, and what is recommended for patients with NTRK fusion-positive advanced solid tumors. CONCLUSION: In the NTRK guideline, the committee proposed 15 recommendations for performing NTRK testing properly to select patients who are likely to benefit from tropomyosin receptor kinase inhibitors.

Predictive factors for hyperprogressive disease during nivolumab as anti-PD1 treatment in patients with advanced gastric cancer.

BACKGROUND: Hyperprogressive disease (HPD) during treatment with anti-programmed death-1/programmed death-ligand 1 monoclonal antibodies has anecdotally been reported in some types of cancers, but is not well-characterized in patients with advanced gastric cancer (AGC). METHODS: Total 62 AGC patients treated with nivolumab in a single institution from September 2017 to April 2018 were enrolled in this study. Tumor responses were assessed according to Response Evaluation Criteria in Solid Tumors version 1.1, and HPD was defined as ≥ two fold increase in tumor growth rate. Clinicopathological and molecular characteristics associated with HPD were also investigated. RESULTS: Thirteen of 62 patients (21%) developed HPD after nivolumab treatment. Overall survival (OS) and progression-free survival (PFS) were significantly shorter in patients with HPD than in patients without HPD (median OS: 2.3 months vs. not reached, P < 0.001; median PFS: 0.7 months vs. 2.4 months, P < 0.001). Liver metastases (77% vs. 41%), Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 1 or 2 (77% vs. 29%), and a large sum of target lesion diameters at baseline (median 104.2 mm vs. 44.9 mm) were significantly associated with HPD. Absolute neutrophil count (ANC) and C-reactive protein (CRP) level significantly increased in the first 4 weeks in only patients with HPD. CONCLUSIONS: HPD was observed in AGC patients treated with nivolumab and correlated with some clinicopathological characteristics. Elevations in ANC and CRP levels upon treatment might indicate HPD.

Clinical practice guidance for next-generation sequencing in cancer diagnosis and treatment (Edition 1.0).

In Japan, the social (medical) health-care system is on the way to being developed to advance personalized medicine through the implementation of cancer genomic medicine, known as "cancer clinical sequencing," which uses a next-generation sequencer. However, no Japanese guidance for cancer genomic testing exists. Gene panel testing can be carried out to help determine patient treatment, confirm diagnosis, and evaluate prognostic predictions of patients with mainly solid cancers for whom no standard treatment is available. This guidance describes how to utilize gene panel testing according to the type of cancer: childhood cancer, rare cancer, carcinoma of unknown primary, and other cancers. The level of evidence classification for unified use in Japan is also detailed. This guidance establishes the basic principles of the quality control of specimens, requirements of medical institutions, informed consent, handling of data during the postanalysis stage, and treatment options based on the evidence level. In Japan, gene panel testing for cancer treatment and diagnosis is recommended to comply with this guidance. This is a collaborative work of the Japanese Society of Medical Oncology, Japan Society of Clinical Oncology, and the Japanese Cancer Association.

Validation of the American Gastroenterological Association guidelines on management of intraductal papillary mucinous neoplasms: more than 5 years of follow-up.

OBJECTIVES: Recent guidelines suggest that imaging surveillance be conducted for 5 years for patients with at most one high-risk feature. If there were no significant changes, surveillance is stopped. We sought to validate this follow-up strategy. METHODS: In study 1, data were analysed for 392 patients with intraductal papillary mucinous neoplasms (IPMNs) and at most one high-risk feature who were periodically followed up for more than 1 year with imaging tests. In study 2, data were analysed for 159 IPMN patients without worsening high-risk features after 5 years (stop surveillance group). RESULTS: In study 1, pancreatic cancer (PC) was identified in 12 patients (27.3%) in the endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) indication group and none in the non-EUS-FNA indication group (P < 0.01). In the EUS-FNA indication group, 11 patients (25%) died, whereas 29 (8.3%) died in the non EUS-FNA indication group (P < 0.01). In study 2 (stop surveillance group), PC was identified in three patients (1.9%) at 84, 103 and 145 months. CONCLUSIONS: PC risk and mortality for IPMNs not showing significant change for 5 years is likely to be low, and the non-EUS-FNA indication can provide reasonable decisions. However, three patients without worsening high-risk features for 5 years developed PC. The stop surveillance strategy should be reconsidered. KEY POINTS: • The AGA guidelines provide reasonable clinical decisions for the EUS-FNA indication. • In stop surveillance group, PC was identified in 3 patients (1.9%). • In stop surveillance group, 2 of 3 PC patients died from PC. • Risk of pancreatic cancer in "stop surveillance" group is not negligible.