Spontaneous regression of multiple solitary plasmacytoma harboring Epstein-Barr virus: a case report and literature review.

We report a rare case of spontaneous regression (SR) in an elderly untreated patient with multiple solitary plasmacytoma (MSP). Diagnosis of MSP was confirmed through surgical resection of the left nasal cavity mass and subsequent biopsy of the right humerus. The patient was considered ineligible for chemotherapy due to poor performance status. At 3-month post-diagnosis, the patient's condition worsened with deteriorating bone lesions and emergence of a new serum monoclonal protein. However, these clinical findings completely disappeared at 6 months, and positron emission tomography-computed tomography at 1 year confirmed complete metabolic remission. Notably, peripheral blood lymphocyte counts were inversely correlated with tumor progression and remission. Pathological re-evaluation of the initial biopsy specimens revealed programmed cell death protein 1 (PD-1) expression in tumor-infiltrating CD8+ T cells. In addition, tumor cells were infected with Epstein-Barr virus (EBV) but were negative for programmed cell death ligand 1 (PD-L1) expression, which is the most potent immune escape mechanism in tumor cells. While the mechanism underlying SR remains unclear, our findings suggest that host immune response as well as EBV infection may contribute to SR. Further studies are needed to elucidate the clinicopathologic mechanisms of tumor regression in plasma cell neoplasms.

Clinical characteristics of patients treated with immune checkpoint inhibitors in EGFR-mutant non-small cell lung cancer: CS-Lung-003 prospective observational registry study.

PURPOSE: Immune checkpoint inhibitors (ICIs) are ineffective against epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). This study aimed to investigate the clinical characteristics of patients who were treated or not treated with ICIs, and of those who benefit from immunotherapy in EGFR-mutant NSCLC. METHODS: We analyzed patients with unresectable stage III/IV or recurrent NSCLC harboring EGFR mutations using a prospective umbrella-type lung cancer registry (CS-Lung-003). RESULTS: A total of 303 patients who met the eligibility criteria were analyzed. The median age was 69 years; 116 patients were male, 289 had adenocarcinoma, 273 had major mutations, and 67 were treated with ICIs. The duration of EGFR-TKI treatment was longer in the Non-ICI group than in the ICI group (17.1 vs. 12.7 months, p < 0.001). Patients who received ICIs for more than 6 months were categorized into the durable clinical benefit (DCB) group (24 patients), and those who received ICIs for less than 6 months into the Non-DCB group (43 patients). The overall survival in the DCB group exhibited longer than the Non-DCB group (69.3 vs. 47.1 months), and an equivalent compared to that in the Non-ICI group (69.3 vs. 68.9 months). Multivariate analysis for time to next treatment (TTNT) of ICIs showed that a poor PS was associated with a shorter TTNT [hazard ratio (HR) 3.309; p < 0.001]. Patients who were treated with ICIs and chemotherapy combination were associated with a longer TTNT (HR 0.389; p = 0.003). In addition, minor EGFR mutation was associated with a long TTNT (HR 0.450; p = 0.046). CONCLUSION: ICIs were administered to only 22% of patients with EGFR-mutated lung cancer, and they had shorter TTNT of EGFR-TKI compared to other patients. ICI treatment should be avoided in EGFR mutated lung cancer with poor PS but can be considered for lung cancer with EGFR minor mutations. Pathological biomarker to predict long-term responders to ICI are needed.

Multicenter, Retrospective Study to Evaluate Necitumumab Plus Cisplatin and Gemcitabine After Immune Checkpoint Inhibitors in Advanced Squamous Cell Lung Cancer in Japan: The NINJA Study.

Introduction: Necitumumab plus gemcitabine and cisplatin (GCN) is a standard therapy for patients with advanced lung squamous cell carcinoma (LSqCC). However, the efficacy and tolerability of GCN in second-line or later treatment for patients previously treated with immune checkpoint inhibitors (ICIs) remain unknown. Methods: This multicenter, retrospective, cohort study assessed the efficacy and tolerability of GCN initiated between November 1, 2019 and March 31, 2022 as second-line to fourth-line treatment in patients with advanced LSqCC who had been pretreated with ICIs. The primary end point was progression-free survival (PFS). Results: A total of 93 patients from 35 institutions in Japan were enrolled. The median PFS, median overall survival (OS), and objective response rate were 4.4 months (95% confidence interval [CI]: 3.8-5.3), 13.3 months (95% CI: 9.6-16.5), and 27.3% (95% CI: 18.3-37.8), respectively. The median PFS, median OS, and objective response rate for second-line, third-line, and fourth-line treatment groups were 4.8 months, 3.8 months, and 4.3 months (p = 0.24); 15.7 months, 11.6 months, and 10.1 months (p = 0.06); and 31.0%, 13.6%, and 37.5% (p = 0.22), respectively. The severity of GCN-related skin disorders was associated with longer PFS (p < 0.05) and OS (p < 0.05). The frequencies of grade ≥3 skin disorders, hypomagnesemia, pneumonitis, and febrile neutropenia were 16.1%, 7.5%, 1.1%, and 4.3%, respectively. There were no treatment-related deaths. Conclusions: GCN for ICI-pretreated patients with LSqCC seems tolerable and offers promising efficacy regardless of treatment line, and ICI pretreatment might enhance GCN efficacy.

Phase III study of bilayer sustained-release tramadol tablets in patients with cancer pain: a double-blind parallel-group, non-inferiority study with immediate-release tramadol capsules as an active comparator.

PURPOSE: We investigated whether twice-daily administration of a bilayer tablet formulation of tramadol (35% immediate-release [IR] and 65% sustained-release) is as effective as four-times-daily IR tramadol capsules for managing cancer pain. METHODS: This randomized, double-blind, double-dummy, active-comparator, non-inferiority study enrolled opioid-naïve patients using non-steroidal anti-inflammatory drugs or acetaminophen (paracetamol) to manage cancer pain and self-reported pain (mean value over 3 days ≥ 25 mm on a 100-mm visual analog scale [VAS]). Patients were randomized to either bilayer tablets or IR capsules for 14 days. The starting dose was 100 mg/day and could be escalated to 300 mg/day. The primary endpoint was the change in VAS (averaged over 3 days) for pain at rest from baseline to end of treatment/discontinuation. RESULTS: Overall, 251 patients were randomized. The baseline mean VAS at rest was 47.67 mm (range: 25.6-82.7 mm). In the full analysis set, the adjusted mean change in VAS was - 22.07 and - 19.08 mm in the bilayer tablet (n = 124) and IR capsule (n = 120) groups, respectively. The adjusted mean difference was - 2.99 mm (95% confidence interval [CI] - 7.96 to 1.99 mm). The upper 95% CI was less than the predefined non-inferiority margin of 7.5 mm. Other efficacy outcomes were similar in both groups. Adverse events were reported for 97/126 (77.0%) and 101/125 (80.8%) patients in the bilayer tablet and IR capsule groups, respectively. CONCLUSION: Twice-daily administration of bilayer tramadol tablets was as effective as four-times-daily administration of IR capsules regarding the improvement in pain VAS, with comparable safety outcomes. CLINICAL TRIAL REGISTRATION: JapicCTI-184143/jRCT2080224082 (October 5, 2018).

A case of synovitis-acne-pustulosis-hyperostosis-osteitis syndrome with right pleural effusion.

A 79-year-old man presented with fatigue and right shoulder pain. Computed tomography revealed right pleural effusion and osteosclerosis of the sternoclavicular joint. There were no signs of malignancy or infection in the pleural fluid studies. His bone scintigraphy exhibited the "bull's head sign." Despite the absence of skin lesions, he was diagnosed with synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) syndrome. Remission was achieved after treatment with non-steroidal anti-inflammatory drugs and oral prednisolone. SAPHO syndrome causes pleural effusion, even in patients without skin lesions. Bone scintigraphy should be considered in the workup for patients with unexplained pleural effusion.

A case of successful desensitization treatment with tepotinib after tepotinib-induced rash.

Tepotinib is one of the key drugs for MET exon 14-skipping mutation-positive non-small cell lung cancer (NSCLC). The main adverse event of tepotinib treatment is edema. Rash is a rare adverse event, affecting only 0.7% of patients. We report a case of successful desensitization after skin rash caused by tepotinib. A 61-year-old male was treated with tepotinib 500 mg as second-line therapy for NSCLC with MET exon 14-skipping mutation. Treatment was discontinued on day 12 due to grade 3 erythema throughout the body. After improvement of the skin rash, he was started on 250 mg tepotinib with an oral antihistamine and topical steroid. Treatment was discontinued on day 11 due to skin rash exacerbation. One month of treatment-free follow-up showed skin rash improvement but lung carcinoma growth. Tepotinib desensitization therapy was started at a dose of 12.5 mg and gradually increased to 250 mg/day. The patient has since continued tepotinib treatment without skin rashes. Desensitization therapy may be effective for managing skin rash due to tepotinib.

A randomized phase II study of afatinib alone or combined with bevacizumab for treating chemo-naïve patients with non-small cell lung cancer harboring EGFR mutations.

BACKGROUND: Adding bevacizumab to first-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) prolonged the progression-free survival (PFS), but limited data are available for second-generation EGFR-TKIs. AfaBev-CS is a randomized, phase II trial comparing afatinib plus bevacizumab and afatinib alone as first-line treatment. PATIENTS AND METHODS: Untreated patients with non-squamous non-small cell lung cancer (NSCLC) harboring EGFR mutations (Del19 or L858R) were enrolled and randomly assigned to receive either afatinib (30 mg) plus bevacizumab (AfaBev group) or afatinib (40 mg) monotherapy (Afa group). The primary endpoint was PFS. The power was >50% under the assumptions of a median PFS of 12 months for the Afa group and hazard ratio (HR) of 0.6 for the AfaBev group. RESULTS: Between August 2017 and September 2019, 100 patients were enrolled. There was no significant difference in PFS between the groups. The median PFS was 16.3 and 16.1 months for the AfaBev and Afa groups, respectively, with an HR of 0.865 (95% confidence interval [CI], 0.539 to 1.388; p = 0.55). In terms of overall survival, there was no significant difference between the groups (HR, 0.84; 95% CI, 0.39 to 1.83; p = 0.67). The overall response rate was 82.6% and 76.6% in the AfaBev and Afa groups, respectively (p = 0.61). Grade ≥ 3 diarrhea, hypertension, acneiform rash, paronychia, and stomatitis were frequently observed in the AfaBev group. CONCLUSIONS: This study failed to show efficacy of AfaBev over Afa for improving PFS in untreated patients with EGFR-mutated NSCLC.

A Retrospective, Multicenter, Observational Study to Evaluate Clinical Outcomes of Lorlatinib After Alectinib in Patients With ALK-Positive NSCLC in Japan.

Introduction: Lorlatinib is an ALK tyrosine kinase inhibitor approved in Japan for the treatment of advanced ALK+ NSCLC. There has been little evidence about lorlatinib efficacy after first-line (1L) alectinib in clinical practice in Japan. Methods: We retrospectively analyzed patients with advanced ALK+ NSCLC previously treated with 1L alectinib at multiple sites in Japan. Primary objectives were to collect patient demographics at baseline and estimate time to treatment failure (TTF) with second-line (2L) or third-line (3L) or later line (≥3L) lorlatinib treatment. Secondary objectives included objective response rate (ORR) with lorlatinib, reason for discontinuation and time to last treatment failure with lorlatinib, TTF and ORR of alectinib, and combined TTF. Results: Among the 51 patients included in the study, 29 (56.9%) received 2L and 22 (43.1%) received ≥3L lorlatinib treatment. At lorlatinib initiation, brain metastases were reported in 25 patients (49.0%), and 32 (62.7%) had an Eastern Cooperative Oncology Group performance status of 0 or 1. Median TTF with lorlatinib was 11.1 months (95% confidence interval [CI]: 4.6-13.8) in any line, 10.8 months (95% CI: 3.9-13.8) in 2L, and 11.5 months (95% CI: 2.9-not reached) in ≥3L. Median TTF was 11.5 months (95% CI: 3.9-not reached) in patients with brain metastases at lorlatinib initiation and 9.9 months (95% CI: 4.3-13.8) in patients without brain metastases. ORR was 35.7% with any-line lorlatinib treatment. Conclusions: Patient characteristics and efficacy were comparable with previous reports when lorlatinib was given after 1L alectinib in patients with ALK+ NSCLC.

Benefit of prednisolone alone in nodal peripheral T-cell lymphoma with T follicular helper phenotype.

A 71-year-old Japanese man presented with severe thrombocytopenia. A whole-body CT at presentation showed small cervical, axillary, and para-aortic lymphadenopathy, leading to suspicion of immune thrombocytopenia due to lymphoma. Biopsy was difficult to perform because of severe thrombocytopenia. Thus, he received prednisolone (PSL) therapy and his platelet count gradually recovered. Two and a half years after PSL therapy initiation, his cervical lymphadenopathy slightly progressed without other clinical symptoms. Hence, a biopsy from the left cervical lymph node was performed, and he was diagnosed with nodal peripheral T-cell lymphoma (PTCL) with T follicular helper (TFH) phenotype. Due to various complications, we continued treatment with prednisolone alone after the diagnosis of lymphoma; however, there was no further increase in lymph node enlargement and no other lymphoma-related symptoms for one and a half years after diagnosis. Although immunosuppressive therapy has been reported to produce a response in some patients with angioimmunoblastic T-cell lymphoma, our experience suggests that a similar subset may exist in patients with nodal PTCL with TFH phenotype, which has the same cellular origin. Immunosuppressive therapies may constitute an alternative treatment option even in the era of novel molecular-targeted therapies, especially for elderly patients who are ineligible for chemotherapy.

Large-scale clinico-genomic profile of non-small cell lung cancer with KRAS G12C: Results from LC-SCRUM-Asia study.

INTRODUCTION: KRAS G12C is an oncogenic driver mutation, accounting for approximately 14% of Caucasian patients with non-small cell lung cancer (NSCLC). Recently, several KRAS G12C-targeted drugs have been developed; however, the clinico-genomic characteristics of NSCLC patients with KRAS G12C remain unclear. MATERIALS AND METHODS: Based on the large-scale prospective lung cancer genomic screening project (LC-SCRUM-Asia) database, the clinico-genomic characteristics and therapeutic outcomes of NSCLC patients with KRAS G12C were evaluated. RESULTS: From March 2015 to March 2021, 10,023 NSCLC patients were enrolled in LC-SCRUM-Asia. KRAS mutations were detected in 1258 patients (14 %), including G12C in 376 (4.0 %), G12D in 289 (3.1 %) and G12V in 251 (2.7 %). The proportions of males and smokers were higher in patients with KRAS G12C than in those with KRAS non-G12C mutations (males: 73 % vs 63 %, p < 0.001; smokers: 89 % vs 76 %, p < 0.001). KRAS G12C-positive tumors showed a higher tumor mutation burden (TMB) (mean, 8.1 mut/Mb, p < 0.001) and a higher percentage of tumors with programmed cell death ligand-1 (PD-L1) expression ≥50 % (52 %, p = 0.08). The overall survival in patients with KRAS G12C (median, 24.6 months) was not different between patients with other mutation subtypes (G12V: 18.2 months, p = 0.23; G12D: 20.6 months, p = 0.65; other KRAS mutations: 18.3 months, p = 0.20). Among KRAS-mutated patients who received immune checkpoint inhibitors (ICIs), the progression-free survival in G12C-positive patients (median, 3.4 months) was similar to that in G12V-positive patients (4.2 months, p = 0.90), but significantly longer than that in G12D- (2.0 months, p = 0.02) and other KRAS mutation-positive patients (2.5 months, p = 0.02). CONCLUSIONS: The frequencies of KRAS G12C were lower in Asian than in Caucasian NSCLC patients. Among the KRAS-mutated NSCLC patients, G12C-positive tumors showed increased immunogenicity, such as high TMB and high PD-L1 expression, and potential sensitivity to ICIs.

A Large-Scale Prospective Concordance Study of Plasma- and Tissue-Based Next-Generation Targeted Sequencing for Advanced Non-Small Cell Lung Cancer (LC-SCRUM-Liquid).

PURPOSE: We evaluated plasma cell-free DNA (cfDNA) and tissue-based sequencing concordance for comprehensive oncogenic driver detection in non-small cell lung cancer (NSCLC) using a large-scale prospective screening cohort (LC-SCRUM-Liquid). EXPERIMENTAL DESIGN: Blood samples were prospectively collected within 4 weeks of corresponding tumor tissue sampling from patients with advanced NSCLC to investigate plasma cfDNA sequencing concordance for alterations in 8 oncogenes (EGFR, KRAS, BRAF, HER2, MET, ALK, RET, and ROS1) compared with tissue-based next-generation targeted sequencing. RESULTS: Paired blood and tissue samples were obtained in 1,062/1,112 enrolled patients with NSCLC. Oncogenic alteration was detected by plasma cfDNA sequencing and tissue assay in 455 (42.8%) and 537 (50.5%) patients, respectively. The positive percent agreement of plasma cfDNA sequencing compared with tissue DNA and RNA assays were 77% (EGFR, 78%; KRAS, 75%; BRAF, 85%; HER2, 72%) and 47% (ALK, 46%; RET, 57%; ROS1, 18%; MET, 66%), respectively. Oncogenic drivers were positive for plasma cfDNA and negative for tissue due to unsuccessful genomic analysis from poor-quality tissue samples (70%), and were negative for plasma cfDNA and positive for tissue due to low sensitivity of cfDNA analysis (61%). In patients with positive oncogenic drivers by plasma cfDNA sequencing but negative by tissue assay, the response rate of genotype-matched therapy was 85% and median progression-free survival was 12.7 months. CONCLUSIONS: Plasma cfDNA sequencing in patients with advanced NSCLC showed relatively high sensitivity for detecting gene mutations but low sensitivity for gene fusions and MET exon 14 skipping. This may be an alternative only when tissue assay is unavailable due to insufficient DNA and RNA. See related commentary by Jacobsen Skanderup et al., p. 1381.

Identification of risk factors for venous thromboembolism and validation of the Khorana score in patients with advanced lung cancer: based on the multicenter, prospective Rising-VTE/NEJ037 study data.

BACKGROUND: Management of cancer-associated venous thromboembolism (VTE) is essential in cancer treatment selection and prognosis. However, currently, no method exists for assessing VTE risk associated with advanced lung cancer. Therefore, we assessed VTE risk, including driver gene mutation, in advanced lung cancer and performed a Khorana score validation. METHODS: The Rising-VTE/NEJ037 study was a multicenter prospective observational study that included patients with advanced lung cancer. In the Rising-VTE/NEJ037 study, the Khorana score was calculated for enrolled patients with available data on all Khorana score components. The modified Khorana score was based on the body mass index of ≥ 25 kg/m2, according to the Japanese obesity standard. A multivariate logistic regression analysis, including patient background characteristics, was performed to evaluate the presence of VTE 2 years after the lung cancer diagnosis. RESULTS: This study included 1008 patients with lung cancer, of whom 100 (9.9%) developed VTE. From the receiver operating characteristic curve analysis, VTE risk could not be determined because both the Khorana score (0.518) and modified Khorana score (0.516) showed very low areas under the curve. The risk factors for VTE in the multivariate analysis included female sex, adenocarcinoma, performance status, N factor, lymphocyte count, platelet count, prothrombin fragment 1 + 2 and diastolic blood pressure. CONCLUSION: The Khorana score, which is widely used in cancer-VTE risk assessment, was less useful for Japanese patients with advanced lung cancer. Prothrombin fragment 1 + 2, a serum marker involved in coagulation, was more suitable for risk identification. CLINICAL TRIAL INFORMATION: jRCTs061180025.

Safety of anti-SARS-CoV-2 messenger RNA vaccine in lung cancer patients undergoing anticancer chemotherapy: A multicenter, prospective, observational, patient-reported outcome study.

BACKGROUND: COVID-19 incidence is high in patients with cancer. The fatality rate was high for the Delta variant, necessitating infection prevention by vaccination. This study evaluated the safety of a SARS-CoV-2 vaccine in patients with advanced lung cancer receiving anticancer therapy. METHODS: We prospectively enrolled patients receiving anticancer drugs for advanced lung cancer and planning SARS-CoV-2 vaccination. Early side effects within 7 days of vaccination were evaluated using patient-reported outcome (PRO) surveys. Chi-square test and multivariate logistic regression analyses were used. RESULTS: Post-vaccination PROs were collected from 406 patients (252 were males). The mean age was 72 years. Treatment at the time of initial vaccination included chemotherapy, immune checkpoint inhibitors (ICI), a combination of chemotherapy and ICI, targeted therapy including tyrosine kinase inhibitors, and others in 115, 93, 45, 147, and six cases, respectively. The vaccines administered were BNT162b2 and mRNA273 in 361 and three cases, respectively and unknown in 42 cases. A total of 16.1% of patients developed fever (38°C) after the second mRNA vaccination (95% confidence interval: 12.6%-20.1%). This rate is comparable to data previously reported in 120 patients and slightly higher than that of healthy participants of the BNT162b2 study. Patients receiving treatment with cytotoxic anticancer agents were more likely to have high fever. Multivariate analysis showed no correlation between fever frequency and patient background. No serious initial adverse events due to vaccination were observed. CONCLUSIONS: Anti-SARS-CoV-2 mRNA vaccination is safe; however, post-vaccination fever is more common in patients undergoing lung cancer treatment than in healthy individuals.

A phase II study of S-1 and cisplatin with concurrent thoracic radiotherapy followed by durvalumab for unresectable, locally advanced non-small-cell lung cancer in Japan (SAMURAI study): primary analysis.

Background: The standard of care for unresectable, locally advanced non-small-cell lung cancer (LA-NSCLC) is chemoradiotherapy (CRT) followed by durvalumab, based on the PACIFIC study. Although multiple Japanese phase II studies have shown high efficacy and tolerability of CRT with cisplatin plus S-1 (SP), no prospective study using durvalumab after SP-based CRT has been reported. Objectives: We conducted a multicenter phase II study of this approach, the interim analysis of which showed a high transition rate to durvalumab consolidation therapy. Here, we report the primary analysis results. Design: In treatment-naïve LA-NSCLC, cisplatin (60 mg/m2, day 1) and S-1 (80-120 mg/body, days 1-14) were administered with two 4-week cycles with concurrent thoracic radiotherapy (60 Gy) followed by durvalumab (10 mg/kg) every 2 weeks for up to 1 year. Methods: The primary endpoint was 1-year progression-free survival (PFS). The expected 1-year PFS and its lower limit of the 80% confidence interval (CI) were set as 63% and 47%, respectively, based on the results of TORG1018 study. Results: In all, 59 patients were enrolled, with 51 (86.4%) proceeding to durvalumab. The objective response rate throughout the study was 72.9% (95% CI: 59.7-83.6%). After median follow-up of 21.9 months, neither median PFS nor OS was reached. The 1-year PFS was 72.5% (80% CI: 64.2-79.2%, 95% CI: 59.1-82.2%), while the 1-year overall survival was 91.5% (95% CI: 80.8-96.4%). No grade 5 adverse events were observed throughout the study. The most common adverse event during the consolidation phase was pneumonitis (any grade, 78.4%; grade ⩾3, 2.0%). Eventually, 52.5% of patients completed 1-year durvalumab consolidation therapy from CRT initiation. Conclusion: This study of durvalumab after SP-based CRT met its primary endpoint and found a 1-year PFS of 73% from CRT initiation. This study provides the first prospective data on the prognosis and tolerability of durvalumab consolidation from the initiation of CRT. Trial registration: Japan Registry of Clinical Trials, jRCTs031190127, registered 1 November, 2019, https://jrct.niph.go.jp/latest-detail/jRCTs031190127.

Prospective analysis of factors precluding the initiation of durvalumab from an interim analysis of a phase II trial of S-1 and cisplatin with concurrent thoracic radiotherapy followed by durvalumab for unresectable, locally advanced non-small cell lung cancer in Japan (SAMURAI study).

Background: The standard of care for unresectable, locally advanced non-small cell lung cancer (LA-NSCLC) is chemoradiotherapy (CRT) followed by durvalumab, based on the PACIFIC trial. Disease progression and pneumonitis were reported as the main reasons to preclude the initiation of durvalumab in multiple retrospective studies. However, the transition rate and the reasons for failure to proceed to consolidation therapy with durvalumab after CRT were not evaluated prospectively. Although phase II studies in Japan have shown high efficacy and tolerability of CRT with cisplatin + S-1 (SP), no prospective study using durvalumab after SP-based CRT has yet been reported. We therefore conducted a phase II study to verify the efficacy and safety of durvalumab following SP-based CRT. In this interim analysis, we report the transition rate and the reasons for its failure. Methods: In treatment-naïve LA-NSCLC, cisplatin (60 mg/m2, day 1) and S-1 (80-120 mg/body, days 1-14) were administered with two 4-week cycles with concurrent thoracic radiotherapy (60 Gy) followed by durvalumab every 2 weeks for up to 12 months. The primary endpoint was 12 month progression-free survival rate. Results: Fifty-nine patients were enrolled, of whom 86.4% (51/59) proceeded to durvalumab. All of them initiated durvalumab within 42 days after CRT [median 18 days (range: 3-38)], including 27.5% (14/51) in <14 days. Common reasons for failure to proceed to durvalumab were disease progression (2/59, 3.4%) and adverse events (6/59, 10.2%). Among the latter cases, four resumed treatment and proceeded to durvalumab within 42 days on off-protocol. The objective response rate and the disease control rate were 62.7% and 93.2%, respectively. The incidences of ⩾grade 3 pneumonitis, febrile neutropenia, and esophagitis were 0%, 8.5%, and 3.4%, respectively. Conclusion: Regarding durvalumab after CRT, this interim analysis of the SAMURAI study clarified the high transition rate, early introduction, and reasons for failure to proceed to consolidation therapy, which were not determined in the PACIFIC trial. Trial registration: Japan Registry of Clinical Trials, jRCTs031190127, registered 1 November, 2019, https://jrct.niph.go.jp/latest-detail/jRCTs031190127.