Progress report of a cross-organ and biomarker-based basket-type clinical trial: BELIEVE Trial.

Cancer genomic medicine using next-generation sequencers has been developing. However, the number of patients who could receive genomically matched therapy is limited because off-label use or patient-oriented compassionate use was not permitted under National Health Insurance in Japan. To improve patient drug accessibility, we initiated a biomarker-based basket-type clinical trial (NCCH1901) in October 2019 under patient-proposed healthcare services. We listed the drugs that had high medical needs but were not covered by National Healthcare Insurance. Then we included these drugs before patient proposal so that they could access off-label drugs soon after they had the results of CGP tests. All drugs were provided free of charge by pharmaceutical companies. The objective was to administer off-label drugs and to collect efficacy and safety data for these drugs. The primary endpoint was the response rate based on the best overall response for up to 16 weeks. As of January 31, 2022, we included 18 drug cohorts and 295 patients were treated in this study. The most common cancer was brain tumor, followed by carcinoma of endocrine organs and colorectal cancer. BRAF mutations and ERBB2 amplifications were the frequent genomic abnormalities to be enrolled. This study was one way to access off-label drugs, and contributed significantly to providing treatment opportunities for patients in Japan.

Identification of barriers to implementation of precision oncology in patients with rare cancers.

Established treatment options for rare cancers are limited by the small number of patients. The current comprehensive genomic profiling (CGP) testing might not fully exploit opportunities for precision oncology in patients with rare cancers. Therefore, we aimed to explore the factors associated with CGP testing utility in rare cancers and identify barriers to implementing precision oncology. Patients who underwent CGP testing at our institution between September 2019 and June 2021 were enrolled in this retrospective study. Based on their results, the patients received molecularly targeted drugs or immune checkpoint inhibitors. Univariate and multivariate analyses evaluated the association between patient characteristics and the proportion of patients receiving molecularly targeted drugs. Overall, 790 patients underwent CGP testing. Among them, 333 patients with rare cancers were identified, of whom 278 (83.5%) had actionable genomic alterations, 127 (38.1%) had druggable genomic alterations, and 25 (7.5%) received genomically matched therapy. The proportion of patients receiving molecularly targeted drugs was significantly higher among those with treatment options with evidence levels A-D (8.7%) than those without treatment options with evidence levels A-D (2.9%). A potential barrier to CGP testing utility in rare cancers is the limited number of molecularly targeted drugs with clinical evidence. We propose that CGP testing be performed in patients with rare cancers who have treatment options with evidence levels A-D to maximize CGP testing utility in real-world practice.

Vaginal Transmission of Cancer from Mothers with Cervical Cancer to Infants.

Two cases of pediatric lung cancer (in 23-month-old and 6-year-old boys) resulting from mother-to-infant transmission of uterine cervical tumors were incidentally detected during routine next-generation sequencing of paired samples of tumor and normal tissue. Spontaneous regression of some lesions in the first child and slow growth of the tumor mass in the second child suggested the existence of alloimmune responses against the transmitted tumors. Immune checkpoint inhibitor therapy with nivolumab led to a strong regression of all remaining tumors in the first child. (Funded by the Japan Agency for Medical Research and Development and others; TOP-GEAR UMIN Clinical Trials Registry number, UMIN000011141.).

Platform trial for off-label oncology drugs using comprehensive genomic profiling under the universal public healthcare system: the BELIEVE trial.

BACKGROUND: Precision medicine has transformed cancer treatment by focusing on personalized approaches based on genomic abnormalities. However, comprehensive genomic profiling (CGP) and access to targeted therapies are limited in Japan. This study investigates the BELIEVE trial, which aims to improve drug accessibility for patients with actionable genetic abnormalities through off-label drug administration. METHODS: The BELIEVE trial is a platform trial with a single master protocol, conducted under the Clinical Trials Act and the patient-proposed health services (PPHS) scheme. Eligible patients with solid tumors exhibiting actionable alterations were enrolled, and CGP tests covered by national health insurance were employed. Treatment selection, study drugs from collaborating pharmaceutical companies, and treatment schedules adhered to predefined protocols. Primary and secondary endpoints were evaluated, and statistical analysis was conducted based on patient response rates. RESULTS: The BELIEVE trial offered treatment opportunities for patients with relapse/refractory disease who lacked standard therapies or clinical trial options. This study addresses unmet medical needs and contributes to the establishment of precision medicine systems. Similar trials like NCI-MATCH and TAPUR are being conducted globally. The BELIEVE trial provides a platform for off-label drug administration, collects essential clinical data, and contributes to drug approval applications. CONCLUSION: The BELIEVE trial provides hope for patients with actionable genetic abnormalities by facilitating access to targeted therapies through off-label drug administration. It establishes a regulatory framework and promotes collaboration between industry and academia by expanding organ-specific and cross-organ biomarker-based treatments.

Loss of H3K27 trimethylation in a distinct group of de-differentiated chordoma of the skull base.

De-differentiated chordoma is defined as a high-grade sarcoma lacking notochordal differentiation, which arises in association with conventional chordoma. The mechanism underlying de-differentiation remains unclear. We immunohistochemically investigated trimethylation at lysine 27 of histone 3 (H3K27me3) in nine de-differentiated chordomas. The tumours occurred at the skull base (n = 5) or the sacrum (n = 4) in four men and five women with a median age of 50 years. De-differentiation occurred de novo in four cases and at recurrence/metastasis in five cases. Five tumours retained H3K27me3, whereas four showed complete loss of H3K27me3 only in the de-differentiated component, while the conventional chordoma component retained H3K27me3. All the H3K27me3-negative tumours showed co-loss of dimethylation at H3K27 (H3K27me2), consistent with inactivation of polycomb repressive complex 2. Two genetically analysed H3K27me3-negative tumours harboured EED homozygous deletions. All four H3K27me3-negative de-differentiated chordomas affected the skull base of young or middle-aged women. Unlike dense proliferation of highly pleomorphic spindle or epithelioid cells in the H3K27me3-positive de-differentiated chordomas, all H3K27me3-negative tumours displayed swirling fascicles of relatively uniform spindle cells with alternating cellularity and perivascular accentuation, resembling malignant peripheral nerve sheath tumour (MPNST). Rhabdomyoblastic differentiation was present in one H3K27me3-negative tumour. We identified a novel group of de-differentiated chordomas in the skull base that lost H3K27me3/me2 only in the de-differentiated component, which was associated with EED homozygous deletion and MPNST-like histology. Our data suggest a distinct 'polycomb-type' de-differentiation pathway in chordoma, similar to a recently described de-differentiated chondrosarcoma with H3K27me3 loss.

Chronological improvement in precision oncology implementation in Japan.

In Japan, comprehensive genomic profiling (CGP) tests for refractory cancer patients have been approved since June 2019, under the requirement that all cases undergoing CGP tests are annotated by the molecular tumor board (MTB) at each government-designated hospital. To investigate improvement in precision oncology, we evaluated and compared the proportion of cases receiving matched treatments according to CGP results and those recommended to receive genetic counseling at all core hospitals between the first period (11 hospitals, June 2019 to January 2020) and second period (12 hospitals, February 2020 to January 2021). A total of 754 and 2294 cases underwent CGP tests at core hospitals in the first and second periods, respectively; 28 (3.7%) and 176 (7.7%) patients received matched treatments (p < 0.001). Additionally, 25 (3.3%) and 237 (10.3%) cases were recommended to receive genetic counseling in the first and second periods, respectively (p < 0.001). The proportion was associated with the type of CGP test: tumor-only (N = 2391) vs. tumor-normal paired (N = 657) analysis (10.0% vs. 3.5%). These results suggest that recommendations regarding available clinical trials in networked MTBs might contribute to increasing the numbers of matched treatments, and that tumor-normal paired rather than tumor-only tests can increase the efficiency of patient referrals for genetic counseling.

Clinical utility of comprehensive genomic profiling tests for advanced or metastatic solid tumor in clinical practice.

Previous clinical trials indicate that 10%-25% of patients received genomically matched therapy after comprehensive genomic profiling (CGP) tests. However, the clinical utility of CGP tests has not been assessed in clinical practice. We assessed the clinical utility of CGP tests for advanced or metastatic solid tumor and determined the proportion of patients receiving genomically matched therapy among those with common and non-common cancers. From August 2019 to July 2020, a total of 418 patients had undergone CGP tests, and the results were discussed through the molecular tumor board at our site. The median age of patients was 57 (range: 3-86) years. Colorectal cancer was the most common, with 47 (11%) patients. Actionable genomic alterations (median 3, range: 1-17) were identified in 368 (88.0%) of 418 patients. Druggable genomic alterations were determined in 196 (46.9%) of 418 patients through the molecular tumor board. Genomically matched therapy was administered as the subsequent line of therapy in 51 (12.2%) patients, which is comparable to the proportion we previously reported in a clinical trial (13.4%) (p = 0.6919). The proportion of patients receiving genomically matched therapy was significantly higher among those with common cancers (16.2%) than non-common cancers (9.4%) (p = 0.0365). Genomically matched therapy after the CGP tests was administered to 12.2% of patients, which is similar to the proportion reported in the previous clinical trials. The clinical utility of CGP tests in patients with common cancers greatly exceeded that in patients with non-common cancers.

Expert panel consensus recommendations on the use of circulating tumor DNA assays for patients with advanced solid tumors.

Comprehensive genomic profiling is increasingly used to facilitate precision oncology based on molecular stratification. In addition to conventional tissue comprehensive genomic profiling, comprehensive genomic profiling of circulating tumor DNA has become widely utilized in cancer care owing on its advantages, including less invasiveness, rapid turnaround time, and capturing heterogeneity. However, circulating tumor DNA comprehensive genomic profiling has some limitations, mainly false negatives due to low levels of plasma circulating tumor deoxyribonucleic acid and false positives caused by clonal hematopoiesis. Nevertheless, no guidelines and recommendations fully address these issues. Here, an expert panel committee involving representatives from 12 Designated Core Hospitals for Cancer Genomic Medicine in Japan was organized to develop expert consensus recommendations for the use of circulating tumor deoxyribonucleic acid-based comprehensive genomic profiling. The aim was to generate guidelines for clinicians and allied healthcare professionals on the optimal use of the circulating tumor DNA assays in advanced solid tumors and to aid the design of future clinical trials that utilize and develop circulating tumor DNA assays to refine precision oncology. Fourteen clinical questions regarding circulating tumor deoxyribonucleic acid comprehensive genomic profiling including the timing of testing and considerations for interpreting results were established by searching and curating associated literatures, and corresponding recommendations were prepared based on the literature for each clinical question. Final consensus recommendations were developed by voting to determine the level of each recommendation by the Committee members.

Appropriate use of cancer comprehensive genome profiling assay using circulating tumor DNA.

Comprehensive genomic profiling (CGP) is being increasingly used for the routine clinical management of solid cancers. In July 2018, the use of tumor tissue-based CGP assays became available for all solid cancers under the universal health insurance system in Japan. Several restrictions presently exist, such as patient eligibility and limitations on the opportunities to perform such assays. The clinical implementation of CGP based on plasma circulating tumor DNA (ctDNA) is also expected to raise issues regarding the selection and use of tissue DNA and ctDNA CGP. A Joint Task Force for the Promotion of Cancer Genome Medicine comprised of three Japanese cancer-related societies has formulated a policy proposal for the appropriate use of plasma CGP (in Japanese), available at https://www.jca.gr.jp/researcher/topics/2021/files/20210120.pdf, http://www.jsco.or.jp/jpn/user_data/upload/File/20210120.pdf, and https://www.jsmo.or.jp/file/dl/newsj/2765.pdf. Based on these recommendations, the working group has summarized the respective advantages and cautions regarding the use of tissue DNA CGP and ctDNA CGP with reference to the advice of a multidisciplinary expert panel, the preferred use of plasma specimens over tissue, and multiple ctDNA testing. These recommendations have been prepared to maximize the benefits of performing CGP assays and might be applicable in other countries and regions.

Study protocol for NCCH1908 (UPFRONT-trial): a prospective clinical trial to evaluate the feasibility and utility of comprehensive genomic profiling prior to the initial systemic treatment in advanced solid tumour patients.

Comprehensive genomic profiling has been approved for use in patients with advanced solid tumours; however, it is only indicated in advanced solid tumour patients without available standard chemotherapeutic treatment or those who have completed standard treatments in Japan, and there are no available data on the clinical feasibility and utility of comprehensive genomic profiling in treatment-naive patients. This multicentre, single-arm, prospective study aims to evaluate the feasibility and utility of the OncoGuide NCC Oncopanel System in treatment-naive patients with six advanced major malignancies: non-small cell lung cancer, breast cancer, gastric cancer, colon cancer, pancreatic cancer and biliary tract cancer (NCCH1908). This study (study cohort) will be compared with the other prospective observational study (control cohort), which enrols patients not receiving comprehensive genomic profiling prior to initial systemic treatment. A total of 200 patients will be enrolled in the study over 21 months. This study has been registered in the UMIN Clinical Trials Registry (www.umin.ac.jp/ctr/) (UMIN000040743). CLINICAL TRIAL REGISTRATION: This study, initiated in June 2020, has been registered in the UMIN Clinical Trials Registry (www.umin.ac.jp/ctr/) (registration number: UMIN000040743). We plan to enrol a total of 200 patients over a period of 21 months.

The initial assessment of expert panel performance in core hospitals for cancer genomic medicine in Japan.

BACKGROUND: Since June 2019, cancer genomic profiling (CGP) tests have been reimbursed by the National Health Insurance system in Japan, with restrictions for government-designated hospitals with a molecular tumor board composed of multidisciplinary specialists, known as an expert panel (EP). The standardization of EPs is a critical challenge for implementing precision oncology in the clinical setting. METHODS: Data on consecutive cases who underwent the CGP tests at 11 core hospitals between June 2019 and January 2020 were collected. We evaluated the proportions of cases that received genomically matched treatments, including investigational new drugs (INDs) based on CGP results, and/or for which genetic counseling was recommended. Two simulated cases were annotated by each EP. The annotated reports were then centrally assessed. RESULTS: Each EP mainly discussed the applicability to genomically matched treatments and the necessity of performing genetic counseling. A pre-review of the report by key members in each EP reportedly made the EP conference more interactive and efficient, and thereby saved time. A total of 747 cases underwent CGP tests, 28 cases (3.7%) received genomically matched treatment, and 17 cases (2.3%) were referred for genetic counseling. Annotated reports for the simulated cases varied across the EPs, particularly the number of recommended IND trials, which seemed to be associated with the actual number of participants in IND trials. CONCLUSIONS: This investigation provides reference data for the application of precision oncology in a clinical setting. Further investigations on the standardization of clinical annotations are warranted.

Clinical practice guidance for next-generation sequencing in cancer diagnosis and treatment (edition 2.1).

BACKGROUND: To promote precision oncology in clinical practice, the Japanese Society of Medical Oncology, the Japanese Society of Clinical Oncology, and the Japanese Cancer Association, jointly published "Clinical practice guidance for next-generation sequencing in cancer diagnosis and treatment" in 2017. Since new information on cancer genomic medicine has emerged since the 1st edition of the guidance was released, including reimbursement for NGS-based multiplex gene panel tests in 2019, the guidance revision was made. METHODS: A working group was organized with 33 researchers from cancer genomic medicine designated core hospitals and other academic institutions. For an impartial evaluation of the draft version, eight committee members from each society conducted an external evaluation. Public comments were also made on the draft. The finalized Japanese version was published on the websites of the three societies in March 2020. RESULTS: The revised edition consists of two parts: an explanation of the cancer genomic profiling test (General Discussion) and clinical questions (CQs) that are of concern in clinical practice. Particularly, patient selection should be based on the expectation that the patient's post-test general condition and organ function will be able to tolerate drug therapy, and the optimal timing of test should be considered in consideration of subsequent treatment plans, not limited to treatment lines. CONCLUSION: We expect that the revised version will be used by healthcare professionals and will also need to be continually reviewed in line with future developments in cancer genome medicine.

Genomic alterations in STK11 can predict clinical outcomes in cervical cancer patients.

OBJECTIVE: Cervical cancer is the fourth most common cause of cancer-related deaths in Asian women, due to its poor prognosis. This study aimed to decipher genomic alteration profiles of a cohort of Japanese cervical cancer patients to understand why certain patients benefited from molecular targeted therapies and their prognostic significance. METHODS: During 2008-2018, 154 cervical cancer patients underwent a potentially curative resection procedure at the National Cancer Center Hospital. Genomic DNA samples were analyzed using Ion AmpliSeq™ Cancer Hotspot Panel v2. Alterations in the copy number of PIK3CA, ERBB2, PTEN, and STK11 were detected using the TaqMan assay. HPV-positive results were confirmed by genomic testing and in situ hybridization assay. RESULTS: The frequency of genomic alterations in PIK3CA (36%), STK11 (16%), PTEN (11%), TP53 (11%), and KRAS (8%) was >5%. KRAS mutations were preferentially detected in patients with adenocarcinomas, and the frequency of PIK3CA mutations in patients with squamous cell carcinomas was higher than that in patients with other histological cancer types. HPV-positive results were observed in 139/154 (90.3%) patients, and TP53 mutants were detected in HPV-negative specimens. In this study, the overall survival of patients with genomic alterations in STK11 was worse than in patients with wild-type STK11 (hazard ratio = 10.6, P = 0.0079) and TCGA dataset (hazard ratio = 2.46, P = 0.029). CONCLUSIONS: More than one-third of Japanese cervical cancer patients exhibit mutations targeted by molecular targeted therapies. We have proposed the prognostic value of STK11 genomic alterations.

Multiplex gene-panel testing for lung cancer patients.

The year 2019 was considered to be the first year of cancer genome medicine in Japan, with three gene-panel tests using next-generation sequencing (NGS) techniques being introduced into clinical practice. Among the three tests, the Oncomine CDx Target test was approved under the category of regular molecular testing for lung cancer, which meant that this test could be used to select patients for molecularly targeted drugs. Conversely, the other two tests, NCC OncoPanel and FoundationOne CDx, were assigned to be used under the National Cancer Genome Medicine Network, and implementation was restricted to patients for whom standard treatment was completed or expected to be completed. These NGS tests can detect a series of genetic alterations in individual tumors, which further promotes the development of therapeutic agents and elucidates molecular pathways. The NGS tests require appropriate tissue size and tumor cell content, which can be accessed only by pathologists. In this report, we review the current reimbursement schema in our national healthcare policy and the requirements of the specimens for NGS testing based on the recently published 'Guidance of Gene-panel Testing Using Next-Generation Sequencers for Lung Cancer', by the Japanese Society of Lung Cancer.

Feasibility and utility of a panel testing for 114 cancer-associated genes in a clinical setting: A hospital-based study.

Next-generation sequencing (NGS) of tumor tissue (ie, clinical sequencing) can guide clinical management by providing information about actionable gene aberrations that have diagnostic and therapeutic significance. Here, we undertook a hospital-based prospective study (TOP-GEAR project, 2nd stage) to investigate the feasibility and utility of NGS-based analysis of 114 cancer-associated genes (the NCC Oncopanel test). We examined 230 cases (comprising more than 30 tumor types) of advanced solid tumors, all of which were matched with nontumor samples. Gene profiling data were obtained for 187 cases (81.3%), 111 (59.4%) of which harbored actionable gene aberrations according to the Clinical Practice Guidelines for Next Generation Sequencing in Cancer Diagnosis and Treatment (Edition 1.0) issued by 3 major Japanese cancer-related societies. Twenty-five (13.3%) cases have since received molecular-targeted therapy according to their gene aberrations. These results indicate the utility of tumor-profiling multiplex gene panel testing in a clinical setting in Japan. This study is registered with UMIN Clinical Trials Registry (UMIN 000011141).

[The Role of Core Hospitals and Cooperative Hospitals for Cancer Genomic Medicine in Japan].

Genomic profiling tests using next-generation sequencer have been approved in December 2018 and their reimbursement by the national health insurance system will start soon. The Ministry of Health, Labor and Welfare assigned "Core Hospitals" and "Cooperative Hospitals" as a framework to provide cancer genomic medicine in Japan. Core Hospitals perform molecular tumor board meetings, called "Expert Panel", to make therapeutic recommendation based on the profiling results in cooperation with "Cooperate Hospitals". National Cancer Center has developed an original genomic profiling system(NCC Oncopanel system)to identify genetic alterations of 114 cancer-related genes. Clinical utility and feasibility of this system is being validated by 50Core and Cooperative Hospitals within the Advanced Medical Care B system.

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.

Picoliter-Droplet Digital Polymerase Chain Reaction-Based Analysis of Cell-Free Plasma DNA to Assess EGFR Mutations in Lung Adenocarcinoma That Confer Resistance to Tyrosine-Kinase Inhibitors.

PURPOSE: The objective of this study was to evaluate the utility of analyzing cell-free plasma DNA (cfDNA) by picoliter-droplet digital polymerase chain reaction (ddPCR) to detect EGFR mutations that confer resistance to tyrosine-kinase inhibitors (TKIs) used for treatment of lung adenocarcinoma (LADC). EXPERIMENTAL DESIGN: Thirty-five LADC patients who received epidermal growth factor receptor (EGFR)-TKI therapy, including ten who received tumor rebiopsy after development of resistance, were subjected to picoliter-ddPCR-cfDNA analysis to determine the fraction of cfDNA with TKI-sensitive (L858R and inflame exon 19 deletions) and -resistant (i.e., T790M) mutations, as well as their concordance with mutation status in rebiopsied tumor tissues. RESULTS: cfDNA samples from 15 (94%) of 16 patients who acquired resistance were positive for TKI-sensitive mutations. Also, 7 (44%) were positive for the T790M mutation, with fractions of T790M (+) cfDNA ranging from 7.4% to 97%. T790M positivity in cfDNA was consistent in eight of ten patients for whom rebiopsied tumor tissues were analyzed, whereas the remaining cases were negative in cfDNA and positive in rebiopsied tumors. Prior to EGFR-TKI therapy, cfDNAs from 9 (38%) and 0 of 24 patients were positive for TKI-sensitive and T790M mutations, respectively. Next-generation sequencing of cfDNA from one patient who exhibited innate resistance to TKI despite a high fraction of TKI-sensitive mutations and the absence of the T790M mutation in his cfDNA revealed the presence of the L747P mutation, a known driver of TKI resistance. CONCLUSION: Picoliter-ddPCR examination of cfDNA, supported by next-generation sequencing analysis, enables noninvasive assessment of EGFR mutations that confer resistance to TKIs. IMPLICATIONS FOR PRACTICE: Noninvasive monitoring of the predominance of tumors harboring the secondary T790M mutation in the activating mutation in EGFR gene is necessary for precise and effective treatment of lung adenocarcinoma. Because cells harboring the T790M mutation are resistant to epidermal growth factor receptor-tyrosine-kinase inhibitors (TKIs), the predominance of tumor cells harboring the T790M mutations influences the choice of whether to use conventional or next-generation TKIs. Digital polymerase chain reaction-based examination of cfDNA is a promising method; however, its feasibility, including its consistency with examination of rebiopsied tumor tissue, has not been fully proven. Here, picoliter-droplet digital polymerase chain reaction technology is presented as a candidate method for testing cfDNA and assessing the predominance of T790M-mutant tumors.

Impact of KRAS mutation on response and outcome of patients with stage III non-squamous non-small cell lung cancer.

The frequency and clinical profile of patients with stage III non-small cell lung cancer harboring KRAS mutations have not yet been well documented. Here, we analyzed hotspot KRAS mutations using high-resolution melting analyses in tumor specimens from patients who received chemoradiotherapy between January 2001 and December 2010 at the National Cancer Center Hospital. The associations between the presence of KRAS mutations and the response rate, relapse-free survival, first relapse sites, survival post-progression and overall survival were investigated. A total of 274 non-squamous non-small cell lung cancer patients received chemoradiotherapy at our hospital. After excluding 121 patients for whom tumor specimens were not available and 34 patients with EGFR mutations, the remaining 119 patients were included in the analysis. KRAS mutations were found at a frequency of 13%. Patients with KRAS mutations had a shorter median relapse-free survival (6.1 vs 10.9 months) and a lower response rate (63% vs 81%). As for the first relapse site, patients with KRAS mutations had fewer local relapses (8% vs 23%) and more brain metastases (46% vs 12%). After disease progression, patients with KRAS mutations had a significantly shorter median survival post-progression (2.5 vs 7.3 months, P = 0.028) and median overall survival (15.1 vs 29.1 months, P = 0.022). Our results suggested that KRAS mutation could be associated with a reduced efficacy of chemoradiotherapy and a shortened survival time.