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BACKGROUND: Genomic profiling of tumors from cancer patients facilitates molecular-guided therapy. The turnaround time is one of important issues to deliver results timely for clinical decisions. The Ion Torrent™ Genexus™ Integrated Sequencer automates all next generation sequencing (NGS) workflows and delivers results within a day. METHODS: In this study, we conducted a feasibility study to evaluate the detection rate of genomic alterations from cell-free total nucleic acid (cfTNA, containing cfDNA and cfRNA) of 119 non-small cell lung cancer using Oncomine Precision Assay on Genexus™ Integrated Sequencer. Oncomine Precision Assay (OPA) covers actionable mutations, copy number variations and fusion genes and that are applicable for the selection of targeted therapy. cfTNA isolated from plasma (derived from 14 ml of blood) were subjected to the Genexus system for library construction, templating, sequencing, and data analyses. RESULTS: The sequencing resulted in median overall depth of 35,773× and median molecular coverage of 2,192× with cfTNA input ranged from 11 to 36 ng. Among the 119 samples evaluated, we detected at least one genomic alteration in plasma cfTNA of 79 cases (66%). When comparing to standard-of-care testing, the sensitivity and specificity of mutation detection in non-small cell lung cancer related genes using liquid biopsy with Genexus-OPA ranged between 49–67% and 93–100%, respectively. 59% of actionable mutations, which were present in tumor tissues, were detected by the Genexus- Oncomine Precision Assay using plasma cfTNA. Among the 5 mutations detected from liquid biopsy only, three mutations are of level 1 evidence according to OncoKB database, highlighting the clinical utilities of liquid biopsy in addressing tumor heterogeneity. Extrathoracic metastasis and levels of lactate dehydrogenase (LDH), C-reactive protein (CRP) and Carcinoembryonic Antigen (CEA) are found to be associated with increased circulating tumor DNA detection. CONCLUSIONS: The Genexus™ Integrated Sequencer system is an automated, accurate NGS system with short turnaround time (TAT) that could assist clinicians to make more timely decision.

Data on the re-administration of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) after osimertinib failure in patients with T790M-positive non-small cell lung cancer (NSCLC) is limited. EGFR-TKI re-administration efficacy may vary between patients with T790M loss and those with T790M persistent with re-biopsy after osimertinib treatment. Patients who received EGFR-TKI re-administration (gefitinib, erlotinib, afatinib, dacomitinib, and osimertinib) after osimertinib failure were identified from our database. T790M mutation status before EGFR-TKI re-administration was analyzed via repeat biopsy. We retrospectively evaluated the efficacy of EGFR-TKI re-administration, especially differences according to the T790M mutation status, via repeat biopsy. Until June 2020, 28 patients received EGFR-TKI re-administration and 17 underwent repeat biopsy after osimertinib failure. Patients were divided into three groups, including the T790M loss group, where active mutation persisted and T790M was lost (13/17); T790M remaining group, where both the active mutation and T790M persisted (3/17); and active mutation loss group where both the active mutation and T790M were lost (1/17). The overall response rate (ORR) of EGFR-TKI re-administration in the T790M loss group was 31% and the disease control rate (DCR) was 54%, which were higher than the ORR of 21% and DCR of 43% in the entire patient population. ORR and DCR of the not re-biopsy group were low (9% and 27%, respectively). The therapeutic effect of EGFR-TKI re-administration in patients with T790M-positive NSCLC after osimertinib failure is limited. EGFR-TKI re-administration may be considered in cases of T790M loss after repeat biopsy.

Background Several companion diagnostic (CDx) tests for epidermal growth factor receptor tyrosine kinase inhibitors (EGFR‐TKIs) have been approved. In our institute, the CDx test for EGFR‐TKIs was changed from the Therascreen test (Therascreen) to the Cobas EGFR v2 test (Cobas) because only Cobas was approved for the use of osimertinib in patients with EGFR‐mutated non‐small cell lung cancer (NSCLC) with T790M mutations. The clinical influence of switching the CDx test has not yet been examined comprehensively. Methods All serial patients with lung cancer tested for EGFR mutations with CDx tests between February 2014 and February 2016 at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research (JFCR) were enrolled in this analysis. Results Therascreen was used as a CDx test for EGFR‐TKI therapy in 607 patients between February 2014 and January 2015, and Cobas was used in 621 patients between February 2015 and February 2016. EGFR mutations were detected in 218 patients (35.9%) and 244 patients (39.3%) tested with Therascreen and Cobas, respectively. At the initial diagnosis, 400 and 459 patients were tested with Therascreen and Cobas, respectively. EGFR mutation subtypes, including del19, L858R, and others, were detected in 13.0%, 17.0%, and 2.5% of patients using Therascreen and 17.4%, 14.4%, and 1.5% of patients using Cobas, respectively. Conclusions No significant impact of switching from Therascreen to Cobas as the CDx test for EGFR mutations in clinical practice was observed. However, the detection pattern of the EGFR mutation subtypes between the two CDx tests was slightly different. Key points Significant findings of the study We examined the influence of changing the EGFR test in 1228 patients in total. The detection rate of EGFR mutations was similar. However, the detection pattern for EGFR subtype mutations was slightly different between the two tests. What this study adds Switching CDx tests from target polymerase chain reaction (PCR)‐ to next‐generation sequencing (NGS)‐based methods may lead to obvious changes in clinical practice. When the CDx test is required to change, the investigation of this influence is warranted in future studies., We examined the influence of changing the EGFR test among target PCR methods in 1228 patients in total. The detection rate of EGFR mutations was similar while the detection pattern for EGFR subtype mutations was slightly different between the two tests. In the future, switching companion diagnostic (CDx) tests from target PCR methods to NGS‐based methods may lead to obvious changes in clinical practice.

Background The usefulness of the Oncomine Dx Target test (Oncomine Dx), a next‐generation sequencing (NGS) test, has already been proven in clinical trials. However, NGS requires high‐quality tumor samples and takes a long time to generate results. The feasibility of NGS for use in advanced non‐small cell lung cancer (NSCLC) patients in clinical practice has not yet been determined. Methods Patients serially diagnosed with advanced NSCLC were evaluated in our hospital. The Oncomine Dx, Cobas EGFR mutation test (Cobas EGFR), and ALK‐IHC were performed. The patients were divided into four sets: the full analysis set (FAS) that referred to patients diagnosed with NSCLC, the intent to perform companion diagnostics (CDx) set (IPS) that referred to patients in which CDx had been ordered regardless of sample quality, the per‐performed CDx set (PPS) that referred to patients who could undergo CDx regardless of the results, and the per‐completed CDx set (CCS) that referred to patients in which informative results were received from the CDx. Results The total number of patients analyzed in the study was 167. The IPS/FAS of Oncomine Dx (80.2%) was lower than that of the ALK‐IHC (85.0%) and Cobas EGFR (92.8%). The CCS/FAS of Oncomine Dx (65.9%) was lower than that of the ALK‐IHC (82.0%) and Cobas EGFR (92.2%). PPS/IPS and CCS/PPS of the Oncomine Dx with nonsurgical biopsy ranged between 78.6% and 90.9%, which was lower than those patients who underwent surgical resection (95.0% and 100%). Conclusions The feasibility of Oncomine Dx in clinical practice was lower than the other CDx. The feasibility of Oncomine Dx will increase by improving the biopsy procedure. Key points Significant study findings The usefulness of a next‐generation sequencing (NGS) test has been proven in clinical trials.The feasibility of NGS is lower than other diagnostics in clinical practice especially with regard to nonsurgical biopsy. What this study adds It is necessary to improve the feasibility of NGS in clinical practice.To improve NGS feasibility, turnaround time must be shortened, and larger samples must be obtained during surgical procedures., The feasibility of Oncomine Dx in clinical practice is relatively low compared with that of the ALK‐IHC and Cobas EGFR.

Background The efficacy of anti‐programmed cell death‐1/ligand 1 antibody monotherapy (anti‐PD‐1/PD‐L1 monotherapy) in patients with active brain metastases (BMs) is not established. Here, we aimed to evaluate the efficacy of anti‐PD‐1/PD‐L1 monotherapy in non‐small cell lung cancer (NSCLC) patients with active BMs. Methods This retrospective study included NSCLC patients treated with second‐line or later‐line anti‐PD‐1/PD‐L1 monotherapy between December 2015 and August 2019. Patients were classified into those with or without active BMs, including symptomatic BMs requiring systemic steroids and untreated BMs. The progression‐free survival (PFS) and overall survival (OS) of the patients with and without active BMs were compared. Intracranial and extracranial tumor responses were evaluated in patients with active BMs. Results We analyzed 197 patients who had received anti‐PD‐1/PD‐L1 monotherapy. Among them, 24 had active BMs. Among those without active BMs, 145 had no BMs and 28 had treated asymptomatic BMs. The PFS and OS of patients with active BMs were significantly shorter than those of patients without active BMs (1.3 vs. 2.7 months; P, The present study showed that anti‐PD‐1/PD‐L1antibody monotherapy was not effective for non‐small cell lung cancer patients with active brain metastases. Intracranial and extracranial response rates were 13.3% and 26.7% respectively. Further studies on immunotherapy are needed for patients with active BMs.

Background/aim STK11/LKB1 mutation has been suggested as a poorly responding candidate biomarker of the anti-programmed cell death-1 (PD-1) antibody; however, the association between STK11/LKB1 expression and the effects of anti-PD-1 antibodies is uncertain. The aim of the study was to correlate the efficacy of pembrolizumab monotherapy and STK11/LKB1 expression in untreated patients with non-small-cell lung carcinoma (NSCLC) and high PD-ligand 1 expression. Patients and methods From February 2017 to January 2020, we retrospectively analyzed 30 previously untreated patients with NSCLC and a tumor proportion score (TPS) ≥50% treated with pembrolizumab monotherapy. STK11/LKB1 expression in tumor tissue was evaluated by immunohistochemistry. Results Twenty-three (76.7%) of the 30 patients were classified with low-STK11/LKB1 expression. The median progression-free survival and overall survival of patients with low-STK11/LKB1 expression was shorter than those with high-STK11/LKB1 expression, although the results were not statistically significant. The disease progression rate for the low-STK11/LKB1 group was higher than that of the high-STK11/LKB1 group. Conclusion STK11/LKB1 expression, as measured by immunohistochemistry, could be a useful biomarker associated with the efficacy of pembrolizumab monotherapy for patients with NSCLC and a TPS ≥50%.

Chemoradiotherapy (CRT) is the standard treatment for locally advanced non-small cell lung cancer (NSCLC). Recently, anti-PD-1 antibody therapy became a key treatment for stage IV NSCLC as the combination of immune checkpoint inhibitors (ICIs) and platinum doublet chemotherapy. However, the efficacy and toxicity of anti-PD-1 therapy for recurrence after CRT in stage III NSCLC are not well examined. Patients who received anti-PD-1 therapy for recurrence after CRT were identified in our clinical database. The safety and efficacy of anti-PD-1 therapy were retrospectively analyzed. From March 1, 2013 to April 30, 2018, there were 20 patients who received anti-PD-1 therapy for recurrence after CRT. The median duration from CRT to initial anti-PD-1 therapy was 9.3 months. 12 patients (60%) were alive and 7 patients (35%) were still receiving anti-PD-1 therapy at the data cutoff point (median follow-up, 13.5 months). The ORR for anti-PD-1 therapy was 45.0%. Median progression-free survival (PFS) and overall survival (OS) from initiation of anti-PD-1 therapy was 8.4 months and 26.2 months, respectively. PFS in patients who had a short interval from last CRT to initial anti-PD-1 therapy seemed to have better outcomes (duration from last CRT to initial anti-PD-1 therapy

Background Most patients treated with anaplastic lymphoma kinase (ALK)‐tyrosine kinase inhibitors for ALK‐positive non‐small cell lung cancer (NSCLC) develop resistance, leading to metastasis, with progression to the central nervous system (CNS) being a primary concern. Although alectinib has better CNS penetration than crizotinib, patients treated with alectinib also develop CNS progression. CNS metastases more likely occurs during crizotinib treatment due to less blood‐brain barrier (BBB) penetration capability than alectinib. CNS progression pattern may be different during crizotinib and alecitinib treatment. Understanding the characteristics of CNS progression is important for developing treatment strategies. Aims We compared the clinical‐radiographic characteristics of CNS metastases among patients undergoing crizotinib and alectinib treatment for ALK‐positive NSCLCs. Methods and results We retrospectively analyzed the radiographic and clinical characteristics of CNS progression in ALK‐positive NSCLC patients treated with crizotinib or alectinib at our hospital between July 2011 and May 2020. CNS and systemic tumor progression were evaluated using computed tomography or magnetic resonance imaging. Fifty‐three and 65 patients were treated with crizotinib and alectinib, respectively. Baseline CNS metastasis was observed in 18 and 27 patients in the crizotinib and alectinib groups, respectively. Among the patients in the crizotinib and alectinib groups who developed disease progression, 15/49 (30.6%) and 9/44 (20.5%) had CNS progression, respectively (P = .344). Intra‐CNS progression‐free survival was significantly longer in the alectinib group than in the crizotinib group (median: 14.0 vs 5.6 months, P = .042). The number of CNS metastases sized ≥3 cm, rate of peritumoral brain edema, and the second progression pattern after treatment continuation was not significantly different between the groups. Conclusion We observed no significant difference in the clinical‐radiographic characteristics of CNS progression between patients undergoing crizotinib and alectinib treatments. Local therapy, including stereotactic radiosurgery, for CNS progression may be suitable and important following alectinib and crizotinib treatment.

Background/aim The Renin-Angiotensin system (RAS) induces immunosuppression in the tumor microenvironment, and RAS inhibitors (RASi) improve the tumor immune microenvironment. We evaluated the impact of RASi on the efficacy anti-programmed cell death-1/Ligand-1 (anti-PD-1/PD-L1) antibodies. Patients and methods This retrospective study analyzed non-small cell lung cancer (NSCLC) patients who received anti-PD-1/PD-L1 antibodies monotherapy as second- or later-line treatment. We classified patients into those with or without use of RASi. Results A total of 256 NSCLC patients were included and 37 patients used RASi. The median PFS of patients treated with RASi was significantly longer than that of patients treated without (HR=0.59, 95%CI=0.40-0.88). The median OS of patients treated with RASi tended to be longer than that of patients treated without (HR=0.71, 95%CI=0.45-1.11). Conclusion The use of RASi was associated with a significantly longer PFS in NSCLC patients treated with anti-PD-1/PD-L1 antibodies. RASi use may enhance the efficacy of anti-PD-1/PD-L1 antibodies.

Background Dissociated responses (DR) are phenomena in which some tumors shrink, whereas others progress during treatment of patients with cancer. The purpose of the present study was to evaluate the frequency and prognosis of DR in non-small cell lung cancer (NSCLC) patients treated with anti-programmed cell death-1/ligand 1 (anti-PD-1/L1) inhibitors. Methods This retrospective study included NSCLC patients who received anti-PD-1/L1 inhibitor as second- or later-line treatment. We excluded patients without radiological evaluation. In patients who showed progressive disease (PD) according to the RECIST 1.1 at the initial CT evaluation, we evaluated all measurable lesions in each organ to identify DR independently of RECIST 1.1. We defined DR as a disease with some shrinking lesions as well as growing or emerging new lesions. Cases not classified as DR were defined as ‘true PD’. Overall survival was compared between patients with DR and those with true PD using Cox proportional hazards models. Results The present study included 62 NSCLC patients aged 27–82 years (median: 65 years). DR and true PD were observed in 11 and 51 patients, respectively. The frequency of DR in NSCLC patients who showed PD to anti-PD-1/L1 was 17.7%. Median overall survival was significantly longer in patients with DR versus true PD (14.0 vs. 6.6 months, respectively; hazard ratio for death: 0.40; 95% confidence interval: 0.17–0.94). Conclusions Patients with DR exhibited a relatively favorable prognosis.

Background Dissociated responses (DR) are phenomena in which some tumors shrink, whereas others progress during treatment of patients with cancer. The purpose of the present study was to evaluate the frequency and prognosis of DR in non-small cell lung cancer (NSCLC) patients treated with anti-program cell death-1/ligand 1 (anti-PD-1/L1) inhibitors. Methods This retrospective study included NSCLC patients who received anti-PD-1/L1 inhibitor as second- or later-line treatment. We excluded patients without radiological evaluation, including brain imaging within 28 days prior to the treatment, and those without measurable lesions. We evaluated all measurable lesions in each organ. We defined DR as a disease with some shrinking lesions as well as growing or emerging new lesions in patients who showed progressive disease (PD), according to the RECIST 1.1 at the initial CT evaluation. Cases not classified as DR were defined as ‘true PD’. Overall survival was compared between patients with DR and those with true PD using Cox proportional hazards models. Results The present study included 62 NSCLC patients aged 27–82 years (median: 65 years). DR and true PD were observed in 11 and 51 patients, respectively. Nivolumab, pembrolizumab, and atezolizumab were administered to 45, 7, and 10 patients, respectively. Median overall survival was significantly longer in patients with DR versus true PD (14.0 vs. 6.6 months; hazard ratio for death: 0.40; 95% confidence interval: 0.17–0.94). Conclusions The frequency of DR in NSCLC patients who showed PD to anti-PD-1/L1 was 17.7%. Patients with DR exhibited a relatively favorable prognosis.

Objectives : Docetaxel (DTX) efficacy increases in patients with non-small cell lung cancer (NSCLC) who had received anti-programmed cell death-1/ligand 1 (anti-PD-1/L1) therapy. However, the effect of ramucirumab (Ram) on DTX efficacy following anti-PD-1/L1 therapy is unknown. Here, we aimed to evaluate the effect of Ram on DTX efficacy following anti-PD-1/L1 therapy. Materials and methods This retrospective study included 99 patients with NSCLC, who were divided into those who had (pre-ICI group) or had not (no-ICI group) received anti-PD-1/L1 antibody before DTX. Both groups were then treated with DTX or DTX plus Ram (DTX/Ram). Patient characteristics were compared between the DTX and DTX/Ram groups and adjusted with inverse probability of treatment weighting using propensity scores and the following confounding variables: age, sex, performance status, smoking status, histology, driver mutation, and line of treatment. We compared DTX/Ram and DTX in terms of efficacy in both the pre-ICI and no-ICI groups. Results In the pre-ICI group, 18 and 21 patients received DTX and DTX/Ram, respectively. In the no-ICI group, 35 and 25 patients received DTX and DTX/Ram. In the no-ICI group, progression-free survival (PFS) and overall survival (OS) were not significantly different between DTX/Ram- and DTX-treated patients (median PFS, 2.6 versus 1.6 months; p = 0.30, median OS; 8.2 versus 8.0 months; p = 0.30). In the pre-ICI group, PFS was significantly longer in DTX/Ram-treated than in DTX-treated patients (median, 5.9 versus 2.8 months; p = 0.03). Hazard ratio for disease progression or death was 0.75 (95% confidence interval, 0.20–0.96). The OS of DTX/Ram-treated patients tended to be longer than that of DTX-treated patients (median, 19.8 versus 8.6 months; p = 0.10). Conclusions DTX efficacy following anti-PD-1/L1 therapy may be enhanced by Ram. Further studies are needed to validate the efficacy of inhibiting the vascular endothelial growth factor pathway following anti-PD-1/L1 therapy.

Sinobronchial syndrome (SBS) is a disease involving chronic upper and lower airway inflammation caused by a decline in bronchial mucociliary transport or mucosal immunity. This article describes a case of refractory SBS that progressed despite macrolide therapy, and discusses the possible causes of the intractable nature of the disease.

Background This study aimed to determine whether the neutrophil-to-lymphocyte ratio (NLR) reflected poor treatment benefits in patients with tumor proportion score (TPS) ≥50% and who under went first-line pembrolizumab monotherapy. Patients and methods This study retrospectively analyzed patients with untreated stage III/IV or recurrent non-small cell lung cancer (NSCLC) with TPS ≥50% and who received pembrolizumab monotherapy at two hospitals between February 2017 and April 2019. The NLR was calculated from pre-treatment complete blood counts. Results A total of 51 previously untreated patients with NSCLC who had TPS ≥50% and who underwent pembrolizumab monotherapy were evaluated. Multivariate analysis revealed that high NLR, Eastern Cooperative Oncology Group performance status (PS) ≥2, stage IV or recurrent cancer, and TPS=50-74% were significantly and independently associated with poor progression-free survival. Moreover, high NLR and PS ≥2 were significantly associated with short overall survival. Conclusion A high pre-treatment NLR was associated with significantly short progression-free and overall survival in previously untreated patients with NSCLC with high expression of programmed cell-death ligand 1 treated with pembrolizumab monotherapy.

Key Clinical Message We present a rare case of gingival cancer with pulmonary metastases that developed life‐threatening complete atrioventricular block and ventricular fibrillation as a result of myocardial metastases. This case suggests that implantable cardioverter defibrillators significantly improve the quality of life in these patients and maintain their performance status.

e14511 Background: The efficacy of anti-programmed cell death-1/ligand 1 (anti-PD-(L)1) for active brain metastases (BMs) is not established, because most clinical trials excluded patients (pts) with active BMs such as untreated, symptomatic, or unstable BMs. The aim of this study was to evaluate the efficacy of anti-PD-(L)1 monotherapy in non-small cell lung cancer (NSCLC) pts with active BMs. Methods: This retrospective study included NSCLC pts who had received anti-PD-(L)1 monotherapy in 2nd or later line between December 2015 and August 2019. Pts who had not evaluated BMs by CT/MRI before anti-PD-(L)1 were excluded. Pts were classified into those with or without active BMs which were defined as untreated or symptomatic BMs or BMs requiring systemic steroids. Progression free survival (PFS) and overall survival (OS) of pts with or without active BMs were compared. Intra-cranial and extra-cranial tumor responses were evaluated in pts with active BMs. Results: In this study, 242 pts who had received anti-PD-(L)1 monotherapy were identified and 197 pts were analyzed. Twenty-four pts were classified to pts with active BMs. Among pts without active BMs, 145 pts had no BMs and 28 pts had treated asymptomatic BMs. PFS of pts with active BMs was significantly shorter than that of pts without active BMs (1.3 versus 2.7 months; p < 0.001). OS of pts with active BMs was significantly shorter than that of pts without active BMs (4.5 vs 16.3 months; p = 0.001). Intracranial response rate (RR) was 13.3% (2/15) and extracranial RR was 26.7% (4/15) in pts with active BMs. In multivariate Cox regression analysis, active BM, poor PS and EGFR/ALK(+) were selected as significant factors associated with poor PFS. Active BM and poor PS were selected as significant factors associated with poor OS. Conclusions: Anti-PD-(L)1 monotherapy is not recommend for pts with active BMs.

Objectives Vascular endothelial growth factor-A (VEGF-A) plays important roles in tumor immune suppression and thus correlates with the efficacy of anti-programmed cell death-1/ligand 1 (anti-PD-1/PD-L1) antibodies. We aimed to determine the association between change in plasma VEGF-A levels and the efficacy of chemotherapy combined with anti-PD-1/PD-L1 antibodies (chemo-PD1) in non-small cell lung cancer (NSCLC) patients. Methods We included NSCLC patients treated with chemo-PD1. Plasma VEGF-A levels were measured at baseline (Pre) and days 7 (D7) and 14 (D14) after the initiation of chemo-PD1. Continuous VEGF-A decrease was determined by comparing Pre with the median value of maximum change rate of posttreatment VEGF-A as cutoff. Patients whose change rates of VEGF-A at both D7 and D14 were consistently lower than the cutoff value were classified into the VEGF-A decrease group, whereas those whose VEGF-A at D7 or D14 were higher than the cutoff level were classified into the VEGF-A no-decrease group. The primary outcome was progression-free survival (PFS). Results A total of 32 patients were evaluated. The median Pre VEGF-A levels was 49 (range, 13–257). The median change rate of VEGF-A at D7 and D14 was -25.6% (range, -77.5–376.9) and -42.3% (range, -100–138.5) respectively. The cutoff value of posttreatment VEGF-A change rate was -9.3%. The PFS was significantly longer in the VEGF-A decrease group than that in the VEGF-A no-decrease group (median, not reached vs 2.4 months; p = 0.017). Conclusions Continuous decrease of plasma VEGF-A levels during treatment may be associated with the efficacy of chemo-PD1.

e21042Background: In clinical practice of advanced NSCLC pts, a control of CNS metastasis is important issue. Several clinical trials of ICIs have demonstrated the survival benefit in advanced NSCL...

A type of sandwich beam, consisting of thin bamboo facings and poplar core, is proposed by the author, in order to increase the use of abundant precocious woods by reinforcing with bamboo layers. The objectives of this study are the experimental characterization of the static bending behaviour of the proposed sandwich beam and examining the theoretical predictability of the behaviour. The moment-deflection curve, computed on the basis of the stress extension across the beam section, corresponded remarkably well to the actual curves from the experiments. This computation method, interpreting the mechanical contribution of the thin bamboo facings to the bending capacity improvement, can be considered effective to estimate the ultimate strength, as well as the elastic plastic deflection evolution of the sandwich beam.

Associating bamboo with weak precocious woods, a type of sandwich beam was conceived. This combination, having bamboo layers that act as a reinforcement, develops the usage of less marketed forest products. This paper is devoted to present the conception of this composite beam and its viability. Following the general description of the beam conception, the first half is focused on the manufacture feasibility including the bond ability of bamboo and the lamina production. In the latter half, in view of the realization, the supplemental cost of reinforcement related with the technical performance is discussed in respect of the economical viability of the product.