The Frequency of Specific KRAS Mutations, and Their Impact on Treatment Choice and Survival, in Patients With Metastatic Colorectal Cancer.

BACKGROUND: Patients with metastatic colorectal cancer (mCRC) and KRAS mutations have a poor prognosis, seemingly dependent on the location of the mutation. This multicenter, retrospective, cohort study assessed the frequency and prognostic value of specific KRAS mutation codon locations in mCRC patients, and survival outcomes in relation to treatment. MATERIALS AND METHODS: Data from mCRC patients treated in 10 Spanish hospitals between January 2011 and December 2015 were analyzed. The main objective was to investigate (1) the impact of KRAS mutation location on overall survival (OS), and (2) the effect of targeted treatment plus metastasectomy and primary tumor location on OS in patients with KRAS mutations. RESULTS: The KRAS mutation location was known for 337/2002 patients. Of these, 177 patients received chemotherapy only, 155 received bevacizumab plus chemotherapy, and 5 received anti-epidermal growth factor receptor therapy plus chemotherapy; 94 patients underwent surgery. The most frequent KRAS mutation locations were G12A (33.8%), G12D (21.4%), and G12V (21.4%). Compared with other locations, patients with a G12S mutation had the shortest median OS (10.3 [95% CI, 2.5-18.0] months). OS was longer in patients who underwent surgery versus those who did not, with a trend toward prolonged survival with bevacizumab (median OS 26.7 [95% CI, 21.8-31.7] months) versus chemotherapy alone (median OS 23.2 [95% CI, 19.4-27.0] months). CONCLUSION: These findings confirm that KRAS mutation location may predict survival outcomes in patients with mCRC, and suggest that pre-/post-operative bevacizumab plus metastasectomy provides survival benefits in patients with KRAS mutations.

Preoperative Risk Stratification of Follicular-patterned Thyroid Lesions on Core Needle Biopsy by Histologic Subtyping and RAS Variant-specific Immunohistochemistry.

Follicular-patterned lesions often have indeterminate results (diagnostic category III or IV) by core needle biopsy (CNB) and fine needle aspiration (FNA). However, CNB diagnoses follicular neoplasm (category IV) more frequently than FNA. Therefore, we aimed to develop a risk stratification system for CNB samples with category III/IV using immunohistochemistry (IHC). The specificity of the RAS Q61R antibody was validated on 58 thyroid nodules with six different types of RAS genetic variants and 40 cases of RAS wild-type. We then applied IHC analysis of RAS Q61R to 207 CNB samples with category III/IV in which all patients underwent surgical resection. RAS Q61R IHC had 98% sensitivity and 98% specificity for detecting the RAS p.Q16R variant. In an independent dataset, the positive rate of RAS Q61R was significantly higher in NIFTP (48%) and malignancies (45%) than in benign tumors (19%). The risk of NIFTP/malignancy was highest in the group with nuclear atypia and RAS Q61R expression (86%) and lowest in the group without both parameters (32%). The high-risk group with either nuclear atypia or RAS Q61R had 67.3% sensitivity, 73.4% specificity, 75.2% positive predictive value, and 65.1% negative predictive value for identifying NIFTP/malignancy. We conclude that RAS Q61R IHC can be a rule-in diagnostic test for NIFTP/malignancy in CNB category III/IV results. Combining of the histologic parameter (nuclear atypia) with RAS Q61R IHC results can further stratify CNB category III/IV into a high-risk group, which is sufficient for a surgical referral, and a low-risk group sufficient for observation.

Epidemiological and molecular evaluation of BRAF, KRAS, NRAS genes and MSI in the development of colorectal cancer.

BACKGROUND AND OBJECTIVES: KRAS, NRAS, BRAF mutations and microsatellite instability (MSI) can be associated with Colorectal Cancer (CRC) development. MATERIAL AND METHODS: We evaluated 828 medical records of CRC patients from a school hospital from January/2016 to December/2020. Variables such as age, gender, ethnicity, literacy level, smoking, alcoholism, primary anatomical site, tumor staging, presence of BRAFV600E, KRAS, NRAS mutations and MSI , survival and metastasis were identified. The statistical analyses were performed (p < 0.05 was considered significant). RESULTS: There was a predominance of males (51.93%), whites (90.70%), low education (72.34%), smokers (73.79%), and non-alcoholics (79.10%). Rectum was the most affected site (42.14%), advanced tumor stage was most prevalent (62.07%), and metastasis occurred in (64.61%). Of the enrolled patients; 204 were investigated for BRAF mutation and detected in (2.94%); 216 for KRAS gene and detected in (26.08%); 210 for NRAS gene, and detected in (25.36%); 370 for MSI and detected in (44.68%). A significant association of CRC with NRAS mutation and alcohol habit (p = 0.043) was observed. The presence of MSI was associated with primary site proximal colon (p < 0.000), distal colon (p = 0.001) and rectum (p = 0.010). CONCLUSION: Patients with CRC are male, over 64 years old, white, with low education, smokers and non-alcoholics. The most affected primary site is rectum in advanced stage with metastasis. CRC is associated with NRAS mutation and alcohol habit, there is increased risk for primary site of proximal colon and MSI; decreased risk for distal colon and rectum in the presence of MSI.

Correlation of KRAS gene mutation and programmed death receptor ligand 1 expression with prognosis of first-line concurrent chemoradiotherapy in patients with locally advanced non-small cell lung cancer / 肿瘤研究与临床

Objective:To investigate the relationship between KRAS gene mutation, programmed death receptor ligand 1 (PD-L1) expression and prognosis of first-line concurrent chemoradiotherapy in patients with locally advanced non-small cell lung cancer.Methods:The clinical data of 50 patients with locally advanced non-small cell lung cancer who were admitted to Nanping First Hospital from January 2018 to December 2021 were retrospectively analyzed. All patients were treated with first-line concurrent chemoradiotherapy. Tissue samples of patients were obtained and paraffin embedded before treatment. Real-time fluorescence quantitative polymerase chain reaction was used to detect the type of KRAS gene mutation in tissues before treatment, and the expression of PD-L1 was determined by immunohistochemistry (the percentage of positive cells in tumor cells ≥1% was positive), and the relationship between KRAS gene status, PD-L1 expression and clinical characteristics and short-term efficacy of patients was analyzed. Patients were followed up for 1 year, and progression-free survival (PFS) curves were plotted by Kaplan-Meier method, and log-rank test was used for comparison. Univariate and multivariate Cox proportional hazards models were used to analyze the influencing factors of PFS.Results:Among the 50 patients, 11 (22.00%) were KRAS mutant, and 36 (72.00%) were PD-L1 positive. Among the 11 patients with KRAS mutation, there were 2 cases of codon 13 mutation and 9 cases of codon 12 mutation in exon 2. The objective response rate (ORR) and clinical control rate (DCR) were 76.00% (38/50) and 86.00% (43/50). There were no significant differences in patients' age, pathological type, TNM stage, ORR and DCR between KRAS mutant group and KRAS wild type group (all P > 0.05). The proportions of male patients [72.73% (8/11) vs. 38.46% (15/39)], patients with smoking history [90.91% (10/11) vs. 20.51% (8/39)] and patients with PD-L1 positive expression [100.00% (11/11) vs. 64.10% (25/39)] in KRAS mutant group were higher than those in KRAS wild type group (all P < 0.05). There were no significant differences in patients' age, pathological type, gender, smoking history, TNM stage, ORR and DCR between PD-L1 positive group and PD-L1 negative group (all P > 0.05). The median PFS time of patients in KRAS mutant group and wild type group was 8.75 and 11.32 months, and the difference in PFS between the two groups was statistically significant ( P = 0.039). The median PFS time of patients with PD-L1 positive and negative was 10.19 and 11.16 months, and there was no statistical significance in PFS between the two ( P = 0.116). Multivariate Cox regression analysis showed that KRAS gene mutation was an independent risk factor for PFS in patients with locally advanced NSCLC after first-line concurrent chemoradiotherapy ( HR = 1.449, 95% CI 1.071-1.196, P = 0.017). PD-L1 expression, smoking history and gender were not independent influencing factors for PFS (all P > 0.05). Conclusions:KRAS gene status is closely related to the prognosis of patients with locally advanced non-small cell lung cancer treated with first-line concurrent chemoradiotherapy, while PD-L1 expression is not.

Value of 18F-FDG PET/CT radiomics for predicting KRAS gene mutations in non-small cell lung cancer / 中华核医学与分子影像杂志

Objective:To assess the predictive efficacy of 18F-FDG PET/CT-based radiomics models for the mutation status of Kirsten rats sarcoma viral oncogene homolog (KRAS) in patients with non-small cell lung cancer (NSCLC). Methods:From January 2016 to January 2021, the 18F-FDG PET/CT images and KRAS testing of 258 NSCLC patients (180 males, 78 females; age: 33-91 years) in the First Affiliated Hospital of the Air Force Military Medical University were retrospectively analyzed. Patients were randomly divided into training set ( n=180) and validation set ( n=78) in the ratio of 7∶3. Tumor lesions on PET and CT images were drawn respectively, and the radiomics features of PET and CT lesions were extracted. The radiomics features were screened by least absolute shrinkage and selection operator (LASSO). CT radiomics score (RS) model, PET/CT RS model and composite models of PET/CT RS combined with screened clinical information were eventually developed. ROC curves were used to assess the predictive efficacy of these models. Results:The CT RS model included 4 radiomics features and the PET/CT RS model included 4 CT radiomics features and 8 PET radiomics features. The CT RS model and the PET/CT RS model both had significant differences in RS between KRAS mutant and wild-type patients in the training set and validation set ( z values: from -8.30 to -4.10, all P<0.001). In predicting KRAS mutations, the composite model of PET/CT RS combined with age showed AUCs of 0.879 and 0.852 in the training and validation sets respectively, which were higher than those of the CT RS model (0.813 and 0.770) and the PET/CT RS model (0.858 and 0.834). The accuracy of the composite model of PET/CT RS combined with age were 81.67%(147/180) and 79.49%(62/78) in the training set and validation set respectively, which were also higher than those of the CT RS model (75.00%(135/180) and 74.36%(58/78)) and the PET/CT RS model (78.89%(142/180) and 78.21%(61/78)). Conclusion:Models based on radiomics features can predict KRAS gene mutation status, and the composite model combining PET/CT RS and age can improve the prediction performance.

BRAF and NRAS prognostic values in conjunctival melanoma: analysis and literature review / Análise do valor prognóstico dos marcadores BRAF e NRAS no melanoma da conjuntiva e revisão da literatura

ABSTRACT Purpose: Conjunctival melanoma is a rare and aggressive tumor with a propensity for regional and distant metastases. This study aimed to analyze BRAF/NRAS markers in conjunctival melanoma and their relationship with tumor recurrences and patient prognosis. Methods: This retrospective, observational, single-center study included consecutive patients with an anatomopathological diagnosis of conjunctival melanoma, registered between January 1992 and December 2019. BRAF/NRAS mutations were analyzed using cobas®4800 kit (Roche®) in samples obtained by excisional or map biopsy. Additionally, the presence of other associated precancerous or tumor lesions was assessed. Results: A total of 12 patients with positive histological samples for conjunctival melanoma were included (7 women, 5 men), with a mean age at diagnosis of 60 years and a mean evolution time of 6.38 ± 3.4 years. BRAF V600E mutation was observed in three biopsies (25%), similar to NRAS Q61X (25%). Recurrences occurred in all patients with positive BRAF or NRAS mutation, and five of these patients developed systemic dissemination (83.33%). Moreover, four of six patients with mutated BRAF or NRAS (66.66%) had histopathological findings of tumor or precancerous lesions. Conclusions: BRAF and NRAS mutations may be risk factors for recurrence and shorter survival in conjunctival melanoma, which would make these patients candidates for targeted therapies and comprehensive and individualized follow-up. All these data warrant standardized prospective studies.

RESUMO Objetivo: O melanoma da conjuntiva é um tumor raro e agressivo, com propensão à disseminação metastática regional e distante. Este estudo tem como objetivo analisar os marcadores BRAF e NRAS no melanoma da conjuntiva e sua relação com recidivas tumorais e com o prognóstico do paciente. Métodos: Este foi um estudo retrospectivo, observacional e unicêntrico de pacientes consecutivos com diagnóstico anatomopatológico de melanoma da conjuntiva feito entre janeiro de 1992 e dezembro de 2019. As mutações BRAF e NRAS foram analisadas com o kit cobas® 4800 (Roche®) em amostras obtidas através de biópsia excisional ou por mapa. Além disso, foi avaliada a presença de lesões pré-cancerosas ou tumorais associadas. Resultados: Foram incluídos 12 pacientes com amostras histológicas positivas para melanoma da conjuntiva (7 mulheres e 5 homens), com idade média ao diagnóstico de 60 anos e tempo médio de evolução de 6,38 ± 3,4 anos. A mutação BRAF V600E foi encontrada em 3 biópsias (25%), bem como a NRAS Q61X (25%). Ocorreram recidivas em todos os pacientes positivos para mutações de BRAF ou NRAS e 5 desses pacientes desenvolveram disseminação sistêmica (83,33%). Além disso, 4 dos 6 pacientes com BRAF ou NRAS mutante (66,66%) apresentaram achados histopatológicos de lesões tumorais ou pré-cancerosas. Conclusões: As mutações BRAF e NRAS podem ser fatores de risco para recorrência e menor sobrevida no melanoma da conjuntiva, o que tornaria esses pacientes candidatos a terapias direcionadas e a um acompanhamento mais abrangente e individualizado. Todos esses dados justificam mais estudos prospectivos padronizados.

Correlation of miR-31 and miR-373 expression with KRAS mutations and its impact on prognosis in colorectal cancer.

INTRODUCTION: Colorectal cancers (CRC) are among the most common cancers. There are different modalities for treatment including chemotherapy, surgery, and radiotherapy. There are some mutations in cancers which can assist in the treatment and better prognosis of patients. In this study, two molecular markers (miR-31 and miR-373) were involved in the pathogenesis of CRC and their association with histopathological features was investigated. As well, the prognostic value of these molecular markers was investigated in CRC patients with or without common KRAS mutations. METHODS: Paraffin blocks of tissue samples from 150 patients who underwent colon surgery between 2018 and 2020 were prepared by the Pathology Department of Imam Hossein Hospital (Tehran, Iran). After DNA and RNA isolation, gene expression of miR-31 and miR-373 was determined using probe-based quantitative real-time polymerase chain reaction (qRT-PCR). Mutations of KRAS were surveyed using conventional PCR and agarose gel electrophoresis. RESULTS: The mean age of the patients was 57.2 ± 13.4 years. KRAS codon 12 and 13 mutations were positive in 31 (20.6%) and 22 (14.6%) cases, respectively. The results showed that KRAS common mutations occurred in 32.6% of Iranian CRC patients. The expression levels of miR-31 and miR-373 increased in CRC patients with KRAS mutations in comparison with patients without these mutations. CONCLUSION: Considering the role of miR-31 and miR-373 in CRC tumor progression, it seems that the CRC patients bearing KRAS mutations have a poorer prognosis respective to patients without KRAS mutations.

Clinical value of circulating tumor cell typing and RAS/RAF gene detection in colorectal cancer / 中国医师杂志

Objective:To investigate the correlation between circulating tumor cell (CTC) detection, RAS/RAF gene mutation and clinicopathological characteristics in patients with colorectal cancer (CRC).Methods:The Amplification Refractory Mutation System (ARMS)-polymerase chain reaction (PCR) were used to detect the gene mutation in the tumor tissues of 138 CRC patients in the Third Affiliated Hospital of Sun Yat-sen University from May 2017 to May 2020. At the same time, the venous blood of 138 patients was collected and enriched for CTC genotyping by mRNA in situ hybridization. The correlation between CTC, RAS/RAF gene mutation and clinicopathological features of CRC patients was analyzed.Results:The mutation rates of KRAS, NRAS and BRAF genes were 48.6%(67/138), 5.1%(7/138) and 1.4%(2/138), respectively; The overall positive rate of CTC was 84.1%(116/138). The positive rates of different CTC types were: 23.1%(32/138) in epithelial type, 71.7%(99/138) in mixed type and 12.3%(17/138) in interstitial type respectively. The positive rate of CTC in CRC patients with clinical stage Ⅲ-Ⅳ, lymph node metastasis (N1-N3) and distant metastasis (M1) was significantly higher than that in CRC patients with stage Ⅰ-Ⅱ, no lymph node metastasis (N0) and no distant metastasis (M0) (all P<0.05). The total number of CTC, mixed CTC and interstitial CTC were positively correlated with clinical stage, lymph node metastasis and distant metastasis (all P<0.05). RAS/RAF gene mutation, gender, age, tumor location and tumor differentiation did not affect the positive rate of CTC (all P>0.05). Conclusions:The results of CTC typing are of great research significance for comprehensive treatment, prognosis assessment and stratified management of CRC, among which the interstitial type of CTC may be a high risk factor for the recurrence and metastasis of CRC.

Correlation between RAS and BRAF V600E gene mutations and clinicopathological characteristics of colorectal cancer / 肿瘤研究与临床

Objective:To investigate the correlation between KRAS, NRAS and BRAF V600E gene mutations and the clinicopathological characteristics of patients with colorectal cancer.Methods:Specimens from 217 patients with colorectal cancer who underwent surgical resection and were pathologically confirmed in Shanxi Province Cancer Hospital from January 2020 to December 2021 were selected, and the clinical data of the patients were retrospectively analyzed. The mutation status of KRAS, NRAS and BRAF V600E genes were detected in the paraffin specimens of surgically-resected tissues by direct sequencing. The mutation rates of KRAS, NRAS and BRAF V600E were compared among patients with different clinicopathological characteristics.Results:The mutation rates of KRAS, NRAS and BRAF V600E in 217 patients with colorectal cancer were 48.4% (105/217), 4.1% (9/217) and 3.7% (8/217), of which 1 patient (0.5%) had both KRAS and NRAS mutations. NRAS gene mutation was not correlated with gender, age, tumor size, tumor location, pathological type, degree of differentiation, depth of invasion, lymph node metastasis, distant metastasis, TNM stage, hemangioma thrombus/nerve invasion (all P>0.05); KRAS mutation rate in patients ≥ 60 year old was higher than that in patients < 60 year old [55.3% (63/114) vs. 40.8% (42/103), χ2 = 4.55, P = 0.033),and there was no correlation between KRAS gene mutation and other clinicopathological features (all P > 0.05); the mutation rate of BRAF V600E gene in colorectal cancerpatients with distant metastasis was higher than that in patients without distant metastasis [16.7% (4/24) vs. 2.1% (4/193), P = 0.006], and there was no correlation between BRAF V600E gene mutation and other clinicopathological features (all P > 0.05). Conclusions:Older colorectal cancer patients may be prone to KRAS gene mutation, and the BRAF V600E gene mutation rate is higher in patients with distant metastasis, and there is no correlation between NRAS gene mutation and clinicopathological characteristics.

Evaluación de la metilación del DNA en tejidos de cáncer colorrectal fijados en formalina y embebidos en parafina (FFPE) / Evaluation of DNA methylation in formalin-fixed, paraffin embedded colorectal cancer tissues (FFPE)

Resumen Las alteraciones en la metilación de dinucleótidos CpG en regiones promotoras es uno de los mecanismos epigenéticos implicados en cáncer que tiene uso potencial como biomarcador. Su evaluación, a partir de tejidos fijados en formalina y embebidos en parafina (FFPE), representa un gran desafío dadas la degradación parcial, el entrecruzamiento y las bajas cantidades del DNA obtenido. En esta nota técnica, describimos un protocolo para el estudio del estado de metilación del promotor distal del proto-oncogén K-RAS, a partir de varias muestras obtenidas de dos tejidos FFPE de cáncer colorrectal con antigüedad de 11 años. Se empleó un protocolo de conversión con bisulfito alternativo al usual; se usó una DNA polimerasa modificada y una PCR anidada y se optimizó la secuenciación directa del DNA convertido con bisulfito. Este protocolo podría ser aplicado para determinar estados de metilación en otros genes y tipos de cáncer en tejidos FFPE.

Abstract Alterations in the methylation of CpG dinucleotides in promoter regions is one of the epigenetic mechanisms involved in cancer that has potential use as a biomarker. Its evaluation from formalin-fixed and paraffin-embedded (FFPE) tissues represents a great challenge given the partial degradation, crosslinking, and low amounts of the obtained DNA. In this technical note we describe a protocol for the study of the methylation status of the distal promoter of the K-RAS proto-oncogene from several samples obtained from two 11-years old FFPE tissues of colorectal cancer. An alternative bisulfite conversion protocol to the usual one was used; a modified DNA polymerase and a nested PCR were used and the direct sequencing of the converted DNA with bisulfite was optimized. This protocol could be applied to determine methylation states in other genes and types of cancer.

Molecular Correlates and Nuclear Features of Encapsulated Follicular-Patterned Thyroid Neoplasms.

BACKGROUND: Assessing nuclear features is diagnostically challenging in the aspect of thyroid pathology. The aim of this study was to determine whether pathologists could distinguish BRAF-like and RAS-like nuclear features morphologically and identify morphological features to differentiate thyroid tumors with RAS-like mutations from encapsulated papillary thyroid carcinoma (PTC) with predominant follicular growth and BRAFV600E mutation. METHODS: Representative whole slide images of 16 encapsulated thyroid tumors with predominant follicular growth were reviewed by 12 thyroid pathologists using a web browser-based image viewer. Total nuclear score was calculated from semi-quantitatively scored eight nuclear features. The molecular profile of RAS and BRAF genes was determined by Sanger sequencing. RESULTS: Total nuclear score ranging 0 to 24 could differentiate BRAF-like tumors from RAS-like tumors with a cut-off value of score 14. The interobserver agreement was the highest for the assessment of nuclear pseudoinclusions (NPIs) but the lowest for nuclear elongation and sickle-shaped nuclei. NPIs were found in tumors with BRAFV600E mutation, but not in tumors with RAS-like mutations. Total nuclear scores were significantly higher for tumors with BRAFV600E than for those with RAS-like mutations (P<0.001). CONCLUSION: Our results suggest that NPIs and high nuclear scores have diagnostic utility as rule-in markers for differentiating PTC with BRAFV600E mutation from benign or borderline follicular tumors with RAS-like mutations. Relaxation of rigid criteria for nuclear features resulted in an overdiagnosis of PTC. Immunostaining or molecular testing for BRAFV600E mutation is a useful adjunct for cases with high nuclear scores to identify true PTC.

Cytoplasmic-membrane egfr predicts expanded ras mutation status in colorectal carcinomas? / Egfr membrano-citoplasmático prediz mutação ras expandida no carcinoma colorretal?

ABSTRACT Background: Inhibitors of the epidermal growth factor (EGFR) represent an effective therapeutic option for patients with metastatic colorectal carcinoma, free of activating mutations in KRAS and NRAS. However, the research of mutations is of high cost and scarcely accessible. The expression of the EGFR by immunohistochemistry predicting the mutation status of the expanded RAS (KRAS and NRAS), may allow treatment by a diagnostic method less costly and more accessible. Aim: Investigate the correlation between the clinical-pathological data, the cytoplasmic-membrane expression of the EGFR and the mutational status of the expanded RAS. Method: A total of 139 patients with colorectal carcinoma from the archives of Instituto Goiano de Oncologia e Hematologia were evaluated. Results: Mutation of the expanded RAS was detected in 78 (56.1%) cases. The EGFR expression was stratified in 23 (16.5%) "positive", 49 (35.2%) "negative" and 67 (48.2%) "uncertain". No significant correlation was found between the mutational status of the RAS and the EGFR expression in comparison to age, gender, location, histological type, histological grade and stage. From 23 "positive" cases, 21 (91.3%) showed wild-type RAS gene, and 49 "negative", 41 (83.7%) presented mutation, resulting in a strong association between EGFR "positive", "negative" groups and the mutational status of the RAS (p<0.001), with 86.1% of accuracy. Conclusions: The cytoplasmic-membrane analysis of the EGFR expression stratified into "positive", "negative" and "uncertain" predicts mutational status of the RAS in 51.7% of the cases (p<0.001), with 86.1% of accuracy.

RESUMO Racional: Inibidores do fator de crescimento epidermal (EGFR) representam opção de terapia efetiva para o câncer colorrectal metastático, na ausência de ativação de mutações KRAS e NRAS. Entretanto, a pesquisa de mutações é cara e pouco acessível. A expressão de EGFR por imuno-histoquímica predizendo o status mutacional do RAS expandido (KRAS e NRAS) poderia permitir o tratamento por método diagnóstico menos caro e mais acessível. Objetivo: Investigar a correlação entre os dados clinicopatológicos, a expressão de EGFR na membrana citoplasmática e o status mutacional do RAS expandido. Método: Estudo retrospectivo de acurácia envolvendo 139 pacientes com carcinoma colorretal. Resultado: A mutação do RAS expandido foi detectada em 78 (56,1%) casos. A expressão de EGFR foi estratificada em 23 (16,5%) casos "positivos", 49 (35,2%) casos "negativos" e 67 (48,2%) "duvidosos". Não houve correlação significante entre o status mutacional do RAS e a expressão de EGFR em relação a idade, gênero, local do tumor, tipo histológico, grau histológico e estádio clínico. Em 23 casos "positivos", 21 (91,3%) mostraram gene RAS tipo selvagem, e em 49 "negativos", 41 (83,7%) apresentaram mutação, resultando em forte associação entre grupos EGFR "positivo" ou "negativo" e o status mutacional do RAS (p<0.001), com 86,1% de acurácia. Conclusão: A análise da expressão de EGFR na membrana citoplasmática estratificada em "positivo", "negativo" e "duvidoso" prediz o status mutacional do RAS em 51,7% dos casos (p<0.001), com 86,1% de acurácia.

[Combined detection of KRAS, NRAS, BRAF and PIK3CA mutations in the plasma and tumor tissues of colorectal cancer patients].

Objective: To analyze the concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations detected in plasma and matched tumor tissues in colorectal cancer patients, in order to provide good evidences to support plasma could be a potential surrogate of tumor tissue for gene mutation test. Methods: One hundred and seventy-five cases of colorectal cancer were collected at the First Hospital of Jilin University, from October 2016 to October 2017.There were 101 males and 74 females, their ages ranged from 28 to 85 years,with median age of 59 years. The KRAS, NRAS, BRAF and PIK3CA gene mutations in the plasma and paired tumor specimens of all patients were detected by next generation sequencing. Results: The results of tissue samples test were gold standard. Comparison of the four genes showed that concordance rates between plasma and tissue samples were 81.1%(Kappa=0.543), 99.4%(Kappa=0.886), 99.4% (Kappa=0.886) and 97.7%(Kappa=0.714) respectively for KRAS, NRAS, BRAF and PIK3CA. The plasma detection rates of these genes were related to tumor stage(P=0.001), but not to gender(P=0.468) and age(P=1.000) of patients. Conclusions: The study shows a high concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations in plasma against mutation status in tumor tissue. In colorectal cancer, tumor tissue remains the best specimen for gene detection. However, patients from tumor tissue specimens cannot be obtained, especially those with advanced metastases, plasma can be used instead of tissue to detect the mutation status of KRAS, NRAS, BRAF and PIK3CA to guide targeted therapy.

Combined detection of KRAS, NRAS, BRAF and PIK3CA mutations in the plasma and tumor tissues of colorectal cancer patients / 中华病理学杂志

Objective@#To analyze the concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations detected in plasma and matched tumor tissues in colorectal cancer patients, in order to provide good evidences to support plasma could be a potential surrogate of tumor tissue for gene mutation test.@*Methods@#One hundred and seventy-five cases of colorectal cancer were collected at the First Hospital of Jilin University, from October 2016 to October 2017.There were 101 males and 74 females, their ages ranged from 28 to 85 years,with median age of 59 years. The KRAS, NRAS, BRAF and PIK3CA gene mutations in the plasma and paired tumor specimens of all patients were detected by next generation sequencing.@*Results@#The results of tissue samples test were gold standard. Comparison of the four genes showed that concordance rates between plasma and tissue samples were 81.1%(Kappa=0.543), 99.4%(Kappa=0.886), 99.4% (Kappa=0.886) and 97.7%(Kappa=0.714) respectively for KRAS, NRAS, BRAF and PIK3CA. The plasma detection rates of these genes were related to tumor stage(P=0.001), but not to gender(P=0.468) and age(P=1.000) of patients.@*Conclusions@#The study shows a high concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations in plasma against mutation status in tumor tissue. In colorectal cancer, tumor tissue remains the best specimen for gene detection. However, patients from tumor tissue specimens cannot be obtained, especially those with advanced metastases, plasma can be used instead of tissue to detect the mutation status of KRAS, NRAS, BRAF and PIK3CA to guide targeted therapy.

[KRAS mutations analysis in mucinous epithelial lesions of the endometrium].

Objective: To investigate the frequency of KRAS mutation in mucinous epithelial lesions of the endometrium, and analyze the correlation between KRAS mutation and the clinicopathologic features. Methods: The cohort included forty-three cases of mucinous epithelial lesions of the endometrium selected from July 2015 to October 2017 from Beijing Obstetrics and Gynecology Hospital, and 22 control cases. Genomic DNA was extracted from formalin-fixed paraffin-embedded tissue sections. Polymerase chain reaction amplification for KRAS exons 2 and 3 was performed, followed by sequencing using capillary electrophoresis. The Fisher exact test was used to compare the prevalence of KRAS mutation among the different groups. Results: The patients'age ranged from 33 to 77 years [mean (55.12±9.34) years, median 55 years]. None of the eight cases of endometrial hyperplasia with mucinous differentiation without atypia showed KRAS mutation. The frequency of KRAS mutations was 1/10 in endometrial atypical hyperplasia, 1/12 in endometrioid carcinoma, 4/11 in endometrial atypical hyperplasia with mucinous differentiation (EAHMD), 6/15 in endometrioid carcinoma with mucinous differentiation (ECMD) and 8/9 in mucinous carcinoma (MC), respectively. The differences were statistically significant between MC versus EC (P<0.01) and MC versus ECMD (P<0.05). Conclusion: The high frequency of KRAS mutation in EAHMD, ECMD and MC indicates that KRAS mutational activation is implicated in the pathogenesis of endometrial mucinous carcinoma.

Epidermal Nevi and Related Syndromes - Part 2: Nevi Derived from Adnexal Structures. / Nevus epidérmicos y síndromes relacionados. Parte 2: Nevus derivados de estructuras anexiales.

Epidermal nevi are hamartomatous lesions derived from the epidermis and/or adnexal structures of the skin; they have traditionally been classified according to their morphology. New variants have been described in recent years and advances in genetics have contributed to better characterization of these lesions and an improved understanding of their relationship with certain extracutaneous manifestations. In the second part of this review article, we will look at nevi derived from the adnexal structures of the skin and associated syndromes.

KRAS mutations analysis in mucinous epithelial lesions of the endometrium / 中华病理学杂志

Objective@#To investigate the frequency of KRAS mutation in mucinous epithelial lesions of the endometrium, and analyze the correlation between KRAS mutation and the clinicopathologic features.@*Methods@#The cohort included forty-three cases of mucinous epithelial lesions of the endometrium selected from July 2015 to October 2017 from Beijing Obstetrics and Gynecology Hospital, and 22 control cases. Genomic DNA was extracted from formalin-fixed paraffin-embedded tissue sections. Polymerase chain reaction amplification for KRAS exons 2 and 3 was performed, followed by sequencing using capillary electrophoresis. The Fisher exact test was used to compare the prevalence of KRAS mutation among the different groups.@*Results@#The patients′age ranged from 33 to 77 years [mean (55.12±9.34) years, median 55 years]. None of the eight cases of endometrial hyperplasia with mucinous differentiation without atypia showed KRAS mutation. The frequency of KRAS mutations was 1/10 in endometrial atypical hyperplasia, 1/12 in endometrioid carcinoma, 4/11 in endometrial atypical hyperplasia with mucinous differentiation (EAHMD), 6/15 in endometrioid carcinoma with mucinous differentiation (ECMD) and 8/9 in mucinous carcinoma (MC), respectively. The differences were statistically significant between MC versus EC (P<0.01) and MC versus ECMD (P<0.05).@*Conclusion@#The high frequency of KRAS mutation in EAHMD, ECMD and MC indicates that KRAS mutational activation is implicated in the pathogenesis of endometrial mucinous carcinoma.

Correlation between K-ras gene mutation and clinicopathological characteristics and prognosis of colorectal cancer patients with different primary sites / 肿瘤研究与临床

Objective To analyze the correlation between K-ras gene mutation and clinicopathological characteristics and prognosis of colorectal cancer patients with different primary sites.Methods The clinical and pathological records of 69 patients who were pathologically confirmed as colorectal cancer and tested K-ras gene status at Wuxi People's Hospital Affiliated to Nanjing Medical University between May 2007 and August 2017 were adopted.The correlation between clinicopathological characteristics and prognosis of colorectal cancer patients with different primary sites and K-ras gene mutation status were retrospectively analyzed.And the patients were visited to adopt the prognosis data and perform the Kaplan-Meier survival analysis.Results The K-ras mutation rate was 50.7％(35/69),including 40.0％(12/30)in left-side colon cancer,73.3％(11/15)in right-side colon cancer and 50.0％(12/24)in rectal cancer.The mutation rate of K-ras gene in patients ≥ 60 years old [61.5％(24/39)vs.36.7％(11/30),χ2= 4.197,P = 0.041] or serum CA19-9 raising up abnormally was conspicuously high [65.6％(19/29)vs.37.5％(15/40),χ 2= 5.486,P =0.019].Other clinicopathological characteristics,such as gender,lesion location,histological classification,TNM stage,serum CEA expression,clinical features had no correlation with K-ras gene mutation status(all P＞ 0.05).And no relationship was found between prognosis and overall survival of colorectal cancer patients with different primary sites and K-ras gene mutation status(χ 2= 0.001,P = 0.997; χ 2= 0.583,P =0.445).In general,the 5-year survival rate of left-side colon cancer patients was highest(76.9％),followed by rectal cancer(69.7％),and right-side colon cancer was lowest(31.3％).The primary site of colorectal cancer was related to the overall survival of patients(χ2=11.004,P =0.004).Conclusions K-ras gene mutation in colorectal cancer is closely related to age and serum CA19-9 levels of the patients.The prognosis of left-side colon cancer is best,rectal cancer second,and right-side colon cancer poorest.Whether K-ras gene mutation is the prognostic factor of colorectal cancer is not clear.Testing the K-ras gene status and serum tumor index expression,distinguish the primary site and age group will provide the theory basis and promote the clinical targeted therapy and improve the survival of colorectal cancer patients.

Research on ligase-ELISA method for detecting K-ras gene mutations / 重庆医学

Objective To research a simple and sensitive K-ras gene mutations detection method in order to be suitable for the routine mutation detection.Methods The corresponding detection locus oligonucleotide probe was designed.By the connection,amplification,labeling and ELISA reaction in probe,the mutation locus genotype was determined by the ELISA reaction detection value.With the six point mutations of G12S,G12R,G12C,G12D,G12A and G12V in 12 codons of K-ras gene as the detection objects,the plasma circulation DNA sample in 72 cases of lung cancer was detected,then the results were compared with those obtained by the direct sequencing.Results Three samples were identified as the G12S,G12R and G12A mutatins by the established method.But no K-ras mutations were detected in the samples by using the direct sequencing,indicating that the direct sequencing had lower sensitivity and was not suitable for the mutation detection of heterogeneous samples such as circulating DNA.Conclusion The simple and sensitive K-ras gene mutation detection method is established and can conduct the routine mutation detection for the heterogeneous samples.