Unraveling the Interplay of KRAS, NRAS, BRAF, and Micro-Satellite Instability in Non-Metastatic Colon Cancer: A Systematic Review.

Microsatellite Instability (MSI-H) occurs in approximately 15% of non-metastatic colon cancers, influencing patient outcomes positively compared to microsatellite stable (MSS) cancers. This systematic review focuses on the prognostic significance of KRAS, NRAS, and BRAF mutations within MSI-H colon cancer. Through comprehensive searches in databases like MEDLINE, EMBASE, and others until 1 January 2024, we selected 8 pertinent studies from an initial pool of 1918. These studies, encompassing nine trials and five observational studies involving 13,273 patients, provided insights into disease-free survival (DFS), survival after recurrence, and overall survival. The pooled data suggest that while KRAS and BRAF mutations typically predict poorer outcomes in MSS colorectal cancer, their impact is less pronounced in MSI contexts, with implications varying across different stages of cancer and treatment responses. In particular, adverse effects of these mutations manifest significantly upon recurrence rather than affecting immediate DFS. Our findings confirm the complex interplay between genetic mutations and MSI status, emphasizing the nuanced role of MSI in modifying the prognostic implications of KRAS, NRAS, and BRAF mutations in colon cancer. This review underscores the importance of considering MSI alongside mutational status in the clinical decision-making process, aiming to tailor therapeutic strategies more effectively for colon cancer patients.

It was not possible to detect BRAF V600E mutation in circulating cell-free DNA from patients with ameloblastoma: A diagnostic accuracy study.

BACKGROUND: The objective of this study is to evaluate the diagnostic accuracy of plasma-based liquid biopsy for the detection of the BRAF V600E mutation in circulating cell-free DNA from patients with ameloblastoma. METHODS: This is a prospective diagnostic accuracy study conducted based on the Standards for Reporting Diagnostic Accuracy recommendations. The index test was the plasma-based liquid biopsy, whereas the reference standard was the conventional tissue biopsy. The target condition was the detection of BRAF V600E mutation. The study population consisted of individuals with ameloblastoma recruited from three tertiary hospitals from Brazil. A negative control group composed of three individuals with confirmed wild-type BRAF lesions were included. The participants underwent plasma circulating cell-free DNA and tumor tissue DNA isolation, and both were submitted to using competitive allele-specific TaqMan™ real-time polymerase chain reaction technology mutation detection assays. Sensitivity and specificity measures and positive and negative predictive values were calculated. RESULTS: Twelve patients with conventional ameloblastoma were included. BRAF V600E mutation was detected in 11/12 (91.66%) ameloblastoma tissue samples. However, the mutation was not detected in any of the plasma-based liquid biopsy circulating cell-free DNA samples in both ameloblastomas and negative control group. The sensitivity and specificity of plasma-based liquid biopsy for the detection of the BRAF V600E mutation in circulating cell-free DNA was 0.0 and 1.0, respectively. The agreement between index test and reference standard results was 26.66%. CONCLUSION: Plasma-based liquid biopsy does not seem to be an accurate method for the detection of the BRAF V600E mutation in circulating circulating cell-free DNA from patients with ameloblastoma, regardless of tumor size, anatomic location, recurrence status, and other clinicopathological features.

A phase 1 study of triple-targeted therapy with BRAF, MEK, and AKT inhibitors for patients with BRAF-mutated cancers.

BACKGROUND: Aberrant PI3K/AKT signaling in BRAF-mutant cancers contributes to resistance to BRAF inhibitors. The authors examined dual MAPK and PI3K pathway inhibition in patients who had BRAF-mutated solid tumors (ClinicalTrials.gov identifier NCT01902173). METHODS: Patients with BRAF V600E/V600K-mutant solid tumors received oral dabrafenib at 150 mg twice daily with dose escalation of oral uprosertib starting at 50 mg daily, or, in the triplet cohorts, with dose escalation of both oral trametinib starting at 1.5 mg daily and oral uprosertib starting at 25 mg daily. Dose-limiting toxicities (DLTs) were assessed within the first 56 days of treatment. Radiographic responses were assessed at 8-week intervals. RESULTS: Twenty-seven patients (22 evaluable) were enrolled in parallel doublet and triplet cohorts. No DLTs were observed in the doublet cohorts (N = 7). One patient had a DLT at the maximum administered dose of triplet therapy (dabrafenib 150 mg twice daily and trametinib 2 mg daily plus uprosertib 75 mg daily). Three patients in the doublet cohorts had partial responses (including one who had BRAF inhibitor-resistant melanoma). Two patients in the triplet cohorts had a partial response, and one patient had an unconfirmed partial response. Pharmacokinetic data suggested reduced dabrafenib and dabrafenib metabolite exposure in patients who were also exposed to both trametinib and uprosertib, but not in whose who were exposed to uprosertib without trametinib. CONCLUSIONS: Concomitant inhibition of both the MAPK and PI3K-AKT pathways for the treatment of BRAF-mutated cancers was well tolerated, leading to objective responses, but higher level drug-drug interactions affected exposure to dabrafenib and its metabolites.

Does BRAF V600E mutation affect recurrence rate of ameloblastomas? Systematic review and meta-analysis.

OBJECTIVE: The objective of this systematic review with meta-analysis was to critically evaluate the available data on the association of the BRAF V600E mutation and recurrence rate of ameloblastomas. MATERIALS AND METHODS: This systematic review was registered in Prospero (CRD42020183645) and performed based on the PRISMA statement. A comprehensive search in PubMed, Web of Science, Scopus and Cochrane Library databases was performed in order to answer the question "Does BRAF V600E mutation affect recurrence rate of ameloblastomas?" Methodological quality and risk of bias of the selected studies were assessed with JBI Critical Appraise Tool. Meta-analysis of quantitative data was conducted with RevMan 5.3 and Jamovi 2.3. RESULTS: The initial search identified 302 articles, and 21 met the inclusion criteria. A total of 855 subjects with ameloblastoma were included in the analysis. The pooled measures for frequency of BRAF V600E mutation was 65.30% (95% CI: 0.56-0.75; p < .001; I2 = 90.85%; τ = 0.205; p < .001), and the pooled recurrence rate was 25.30% (95% CI: 0.19-0.31; p < .001; I2 = 79.44%; τ = 0.118; p < .001). No differences in recurrence rate were observed between the BRAF V600E and wild type BRAF ameloblastomas, with a pooled Odds Ratio of 0.93 (95% CI: 0.56-1.54; p = .78; I2 = 31%; p = .09). CONCLUSIONS: BRAF V600E mutation is a frequent event in ameloblastomas, but does not increase nor reduce its recurrence rate, and thus have a limited value in predicting its prognosis.

[Molecular pathology of colorectal cancer]. / Molekularpathologie kolorektaler Karzinome.

In recent years, the treatment of colorectal carcinoma has experienced increasing individualization. In addition to RAS and BRAF mutational status that is firmly established in routine diagnostics, new therapeutic options evolved based on MSI and HER2 status as well as primary tumour localization. Offering the best targeted options in therapy requires new evidence-based decision-making algorithms regarding timing and scope of molecular pathological diagnostics in order for patients to receive an optimized therapy according to current treatment guidelines. New targeted therapies, some of which are about to be approved and for which pathology has to provide new molecular pathological biomarkers, will also play an increasingly important role in the future.

Association between macrocalcification and papillary thyroid carcinoma and corresponding valuable diagnostic tool: retrospective study.

BACKGROUND: Microcalcifications are suggested to be an indicator of thyroid malignancy, especially for papillary thyroid carcinoma (PTC), nonetheless, the association between macrocalcification and PTC is underexplored. Furthermore, screening methods like ultrasonography and ultrasound-guided fine needle aspiration biopsy (US-FNAB) are limited in evaluating macro-calcified thyroid nodules. Thus, we aimed to investigate the relationship between macrocalcification and PTC. We also explored the diagnostic efficiency of US-FNAB and proto-Oncogene Proteins B-raf V600E (BRAF V600E) mutation in macro-calcified thyroid nodules evaluation. METHODS: A retrospective research of 2645 thyroid nodules from 2078 participants was performed and divided into three groups as non-, micro-, and macro-calcified for further PTC incidence comparison. Besides, a total of 100 macro-calcified thyroid nodules with both results of US-FNAB and BRAF V600E mutation were screened out for subsequent evaluation of diagnostic efficiency. RESULTS: Compared to non-calcification, macrocalcification showed a significantly higher incidence of PTC (31.5% vs. 23.2%, P<0.05). Additionally, when compared with a single US-FNAB, the combination of US-FNAB and BRAF V600E mutation showed better diagnostic efficiency in diagnosing macro-calcified thyroid nodule (area under the curve (AUC) 0.94 vs. 0.84, P=0.03), with a significantly higher sensitivity (100.0% vs. 67.2%, P<0.01) and a comparable standard of specificity (88.9% vs. 100.0%, P=0.13). CONCLUSIONS: Occurrence of macrocalcification in thyroid nodules may suggest a high risk of PTC, and the combination of US-FNAB and BRAF V600E showed a greater value in identifying macro-calcified thyroid nodules, especially with significantly higher sensitivity. TRIAL REGISTRATION: The Ethics Committee of The First Affiliated Hospital of Wenzhou Medical University (2018-026).

BRAF inhibitor cessation prior to disease progression in metastatic melanoma: Long-term outcomes.

BACKGROUND: BRAF mutant melanoma treated with BRAF ± MEK inhibitor (targeted therapy) has a high response rate; however, most patients progress (PD). Some patients have durable response, but it is unknown whether treatment can be discontinued in these patients. We describe the recurrence risk, progression patterns, response to subsequent treatment, and survival of patients with advanced melanoma who ceased targeted therapy prior to PD. PATIENTS AND METHODS: Ninety-four patients who ceased targeted therapy without progression were identified retrospectively from 11 centres: 45 were male; 81 V600E; 88 stage IV. Fifty-nine were treated with BRAF + MEK inhibitor, and 35 were treated with BRAF inhibitor alone. Median treatment duration was 29.6 months (range 0.36-77.9). At cessation, 67 were in complete response, 21 in partial response, and 2 stable disease. RESULTS: After median follow-up from cessation of 42.9 months (range 0.0-88.7), 36 (38%) progressed; median time to progression was 4.7 months (range 0.7-56.9); 30 (83%) were asymptomatic and 7 (19%) had new brain metastases. Progression rates did not differ by best response: 34% for complete response and 43% for partial response (P = 0.65). Treatment duration was strongly associated with risk of progression: Median treatment duration was 18.3 (range 0.85-65.7) months for those who progressed and 34.6 (range 0.36-77.9) months for those who did not (P = 0.0004). Twenty-two received further targeted therapy with 15 (68%) responses. CONCLUSION: Risk of progression after cessation of targeted therapy is strongly associated with treatment duration. Response to retreatment with targeted therapy is high.

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.

Presença de mutações no gene BRAF e outros oncogenes e associação com características clínicas e epidemiológicas em pacientes com melanoma metastático / Presence of risk in the BRAF gene and other oncogenes and association with clinical and epidemiological characteristics in patients with metastatic melanoma

Embora o melanoma seja representado por apenas cerca de 5% dos casos de tumores malignos de pele, é responsável pela ampla maioria de óbitos relacionados a tumores cutâneos. Seu desenvolvimento está principalmente associado à presença de mutações em oncogenes específicos, como BRAF, c-KIT e PDGFRA, os quais estão relacionados ao metabolismo celular. OBJETIVOS: Avaliar retrospectivamente a presença de mutações nos genes BRAF (éxons 15), C-KIT (éxons 9,11,13 e 17) e PDGFRA (éxons 12 ,14 e 18) e correlacionar os resultados com as características clínicas e epidemiológicas e desfecho dos pacientes. METODOLOGIA: Foi realizado um estudo retrospectivo de 94 pacientes com melanoma metastático atendidos no Hospital Amaral Carvalho entre os anos de 2015 a 2022, de acordo com as seguintes variáveis: idade ao diagnóstico, gênero, cor, local do tumor primário, local de metástase, subtipo histológico de melanoma, dosagem de LDH, positividade para marcadores de imuno-histoquímica, espessura, presença de ulceração, metástase no linfonodo ao diagnóstico do tumor primário, espessura Breslow, classificação Clark, índice mitótico e desfecho (óbito, sobrevida). RESULTADOS: A maioria dos pacientes eram do sexo masculino (52,1%), de cor branca (97,9%) e com idade acima de 60 anos (42,5%). O subtipo histológico mais encontrado foi o extensivo superficial (42,5%), sendo os membros inferiores o local mais acometido (35,1%). O nível IV de Clark (39,4%) e índice de Breslow acima de 4mm (33,0%) foram os mais prevalentes. A maior parte dos tumores não apresentou ulceração (53,2%) e mais da metade dos pacientes apresentou mais de uma mitose por mm² (47,9%). A dosagem de desidrogenase láctica (LDH) se manteve dentro da normalidade na maioria dos pacientes no momento do diagnóstico (43,6%) e no surgimento de metástases (30,9%). Todos os pacientes apresentaram ao menos uma metástase, sendo os linfonodos regionais o local de maior incidência. A maioria dos pacientes faleceu em decorrência da doença (66,0%). A análise de BRAF apresentou significância estatística para as variáveis idade ao diagnóstico (p= 0,0085), tipo histológico (p= 0,048) e nível de Clark (p= 0,0290). A mediana de sobrevivência para pacientes com mutações em BRAF foi de 62 meses e 50 meses para aqueles que não apresentaram mutações. Não foram encontradas significâncias estatísticas entre c-KIT e as variáveis analisadas. A mediana de sobrevivência para pacientes com mutações em c-KIT foi de 38 meses e 70 meses para aqueles que não apresentaram mutações. CONCLUSÕES: A presença de mutação em BRAF esteve associada à menor idade e menores índices de Clark, e relacionada à ligeira maior sobrevida. O contrário foi observado para mutações em c-KIT, apesar da ausência de significância estatística: uma ligeira menor sobrevida foi observada em pacientes mutados. O LDH não esteve bem correlacionado à presença do melanoma metastático ao se apresentar normal na maioria dos casos. Grande parte dos pacientes tiveram o tumor primário localizado nos membros inferiores, diferentemente do relatado por outros estudos, e apesar de não significante, os tumores de tronco foram em sua maioria mutados para BRAF, e o oposto observado em membros inferiores e superiores. Assim, o papel prognóstico da mutação em BRAF na progressão da doença é ainda controverso. Tais dados podem fornecer mais informações para a adequação de protocolos de prevenção e tratamento de pacientes acometidos por melanoma.

INTRODUCTION: Although melanoma is represented by only about 5% of cases of malignant skin tumors, it is responsible for the vast majority of deaths related to skin tumors. Its development is mainly associated with the presence of mutations in specific oncogenes, such as BRAF, c-KIT and PDGFRA, which are related to cell metabolism. OBJECTIVES: Retrospectively evaluate the presence of mutations in BRAF (exons 15), C-KIT (exons 9,11,13 and 17) and PDGFRA (exons 12, 14 and 18) genes and correlate the results with the clinical and epidemiological characteristics and patient outcomes. METHODS: A retrospective study of 94 patients with metastatic melanoma treated at Hospital Amaral Carvalho between the years 2015 to 2022 was carried out, according to the following variables: age at diagnosis, gender, color, site of primary tumor, site of metastasis, histological subtype of melanoma, LDH dosage, positivity for immunohistochemical markers, thickness, presence of ulceration, lymph node metastasis at diagnosis of the primary tumor, Breslow thickness, Clark classification, mitotic index and outcome (death, survival). RESULTS: Most patients were male (52.1%), white (97.9%) and aged over 60 years (42.5%). The most common histological subtype was superficial extensive (42.5%), with the lower limbs being the most affected site (35.1%). Clark's level IV (39.4%) and Breslow thickness above 4mm (33.0%) were the most prevalent. Most tumors did not show ulceration (53.2%) and more than half of the patients had more than one mitosis per mm² (47.9%). The lactate dehydrogenase (LDH) dosage remained within the normal range in most patients at the time of diagnosis (43.6%) and at the onset of metastases (30.9%). All patients had at least one metastasis, with regional lymph nodes being the site with the highest incidence. Most patients died as a result of the disease (66.0%). BRAF analysis showed statistical significance for the variables age at diagnosis (p= 0.0085), histological type (p= 0.048) and Clark's level (p= 0.0290). Median survival for patients with BRAF mutations was 62 months and 50 months for those without mutations. No statistical significance was found between c-KIT and the analyzed variables. The median survival for patients with c-KIT mutations was 38 months and 70 months for those without mutations. CONCLUSIONS: The presence of a BRAF mutation was associated with younger age and lower Clark scores, and related to slightly longer survival. The opposite was observed for mutations in c-KIT, despite the absence of statistical significance: a slightly lower survival was observed in mutated patients. LDH was not well correlated with the presence of metastatic melanoma as it was normal in most cases. Most of the patients had the primary tumor located in the lower limbs, unlike what has been reported by other studies, and although not significant, the trunk tumors were mostly mutated to BRAF, and the opposite was observed in the lower and upper limbs. Thus, the prognostic role of the BRAF mutation in disease progression is still controversial. Such data may provide more information for the adequacy of prevention and treatment protocols for patients affected by melanoma.

Significance of BRAF V600E mutation in prediction of the efficacy of apatinib for radioactive iodine-refractory differentiated thyroid cancer / 中华核医学与分子影像杂志

Objective:To investigate the significance of B-Raf proto-oncogene, serine/threonine kinase (BRAF) V600E mutation in the prediction of response to apatinib treatment in advanced radioactive iodine-refractory differentiated thyroid cancer (RAIR-DTC). Methods:Twenty patients (10 males, 10 females, age: 51.5(46.3, 65.0) years) with advanced RAIR-DTC from Peking Union Medical College Hospital between March 2016 and March 2023 were retrospectively enrolled, and all patients were treated with apatinib and underwent genetic sequencing (including BRAF V600E and telomerase reverse transcriptase (TERT) promoter). The serological and imaging data, progression-free survival (PFS) and overall survival (OS) data were collected during apatinib treatment. The Kaplan-Meier survival analysis (log-rank test) was performed, and Mann-Whitney U test were used to analyze the differences of duration of response (DOR) between mutation group and wild-type group. Then univariate and multivariate Cox regression analyses were conducted. Results:The PFS (35.3 vs 9.2 months, χ2=7.53, P=0.006) and DOR (25.8(7.4, 35.2) vs 8.2(2.5, 13.4) months, U=23.00, P=0.046) of the BRAF V600E mutation group were longer than those of the wild-type group. Univariate Cox regression analysis showed that the BRAF V600E mutation group had better PFS benefit (hazard ratio ( HR)=0.22 (95% CI: 0.06-0.72), P=0.013), and the risk of disease progression or death in patients with lung metastasis and bone or brain metastasis was 3.06(95% CI: 1.10-8.54, P=0.033) times higher than that in patients with lung metastasis alone. Further, multivariate cox regression analysis showed that only BRAF V600E mutation was an independent predictor of PFS ( HR=0.23 (95% CI: 0.07-0.80), P=0.021), suggesting that RAIR-DTC patients with BRAF V600E mutation might have better efficacy of apatinib. There was no significant difference in PFS ( χ2=1.34, P=0.247) and OS ( χ2=0.19, P=0.664) between TERT promoter mutation group and wild-type group. Conclusion:RAIR-DTC patients with BRAF V600E mutation have longer PFS and DOR after apatinib treatment than those with BRAF V600E wild-type, suggesting that BRAF V600E may be a potential biomarker to guide tyrosine kinase inhibitor (TKI) therapy and help to refine TKI treatment indications.

Diagnostic value of BRAF V600E mutation detection in BSRTC categories Ⅰ and Ⅲ thyroid nodules / 中华核医学与分子影像杂志

Objective:To evaluate the value of B-Raf proto-oncogene, serine/threonine kinase (BRAF) V600E mutation detection in the differentiating malignant from benign with Bethesda system for reporting thyroid cytopathology (BSRTC) categories Ⅰ and Ⅲ nodules. Methods:From January 2019 to December 2020, a total of 264 nodules from 263 patients (79 males, 184 females; median age 46 years) were retrospectively enrolled and all patients underwent BRAF V600E mutation detection, fine-needle aspiration cytology (FNAC) and thyroid nodulectomy in the Affiliated Drum Tower Hospital of Nanjing University Medical School. Thirteen nodules of 12 patients had repeat aspirate samples and 51 nodules were examined with multiple genes assay in formalin fixed paraffin embedded tissues. Taken the postoperative histopathological results as the gold standard, the diagnostic efficiency of BRAF V600E mutation was analyzed by comparing the results of multiple genes assay and BRAF V600E mutation detection of repeated puncture samples. Results:Of 264 nodules, 230 were malignant (papillary thyroid cancer (PTC)) and 34 were benign, with BSRTC categories Ⅰ (nondiagnostic) and Ⅲ (follicular lesion) nodules of 58 and 206. The sensitivities of BRAF V600E mutation detection in BSRTC categories Ⅰ and Ⅲ nodules were 77.1%(37/48) and 78.0%(142/182), the specificities were 9/10 and 91.7%(22/24), the positive predictive values were 97.4%(37/38) and 98.6%(142/144), the negative predictive values were 45.0%(9/20) and 35.5%(22/62), and the accuracy rates were 79.3%(46/58) and 79.6%(164/206). The diagnostic concordance of BRAF V600E mutation detection was 90.2%(46/51) in the preoperative and postoperative samples of 51 nodules with preoperative BRAF V600E wild type but postoperative pathology confirmed as PTC and was 11/13 in repeat puncture samples. Conclusion:BRAF V600E mutation detection is an effective diagnostic method for BSRTC categories Ⅰ and Ⅲ nodules.

BRAF V600E Mutation in Ameloblastoma: A Systematic Review and Meta-Analysis.

The discovery that ameloblastoma has a high mutation incidence of BRAF V600E may enable a better investigation of pathophysiology. However, there is inconsistent evidence regarding this mutation occurrence and its association with clinical information. This systematic review and meta-analysis aim to pool the overall mutation prevalence of BRAF V600E in reported ameloblastoma cases and to determine its association with patient demographic and clinicopathological features. Following the PRISMA guidelines, a comprehensive article search was conducted through four databases (Scopus, Google Scholar, PubMed, and Web of Science). Seventeen articles between 2014 and 2022 met the inclusion criteria with 833 ameloblastoma cases. For each included study, the significance of BRAF V600E on the outcome parameters was determined using odd ratios and 95% confidence intervals. Meta-analysis prevalence of BRAF V600E in ameloblastoma was 70.49%, and a significant meta-analysis association was reported for those younger than 54 years old and in the mandible. On the contrary, other factors, such as sex, histological variants, and recurrence, were insignificant. As a result of the significant outcome of BRAF V600E mutation in ameloblastoma pathogenesis, targeted therapy formulation can be developed with this handful of evidence.

Three cases of BRAF-mutant melanoma with divergent differentiation masquerading as sarcoma.

Melanoma is an important cause of skin cancer related death throughout the world, particularly in Europe, the United States, and Australia. Rarely melanoma undergoes divergent differentiation to simulate the full morphologic and immunohistochemical features of other malignancies, notably sarcoma. However, such cases retain the molecular signatures of melanoma, including BRAF gene mutations. Gene mutation analysis of tumour DNA, now standard practice for all melanomas of stage III or above, may establish the diagnosis of melanoma in some advanced malignancies of unknown lineage. A prior history of melanoma or risk factors for melanoma may be the first clue that an advanced malignancy represents metastatic melanoma. Recognition of this presentation of melanoma can allow a patient to access well-tolerated life-prolonging therapies such as targeted therapy, inhibiting the BRAF/MEK pathway, and immune checkpoint inhibitor therapy.

Phenotype expansion of variants affecting p38 MAPK signaling in hypospadias patients.

BACKGROUND: Hypospadias is a congenital anomaly of the male urogenital system. Genetics factors play an important role in its pathogenesis. To search for potential causal genes/variants for hypospadias, we performed exome sequencing in a pedigree with three patients across two generations and a cohort of 49 sporadic patients with hypospadias. RESULTS: A novel BRAF variant (NM_004333.6: c.362C > A) was found to co-segregate with the hypospadias phenotype in the disease pedigree. In cells overexpressing the BRAF mutant, the phosphorylation level of p38 MAPK was significantly increased as compared with the cells overexpressing the wild-type BRAF or RASopathy-related BRAF mutant. This variant further led to a reduced transcription level of the SRY gene, which is essential for the normal development of the male reproductive system. In the cohort of sporadic patients, we identified two additional variants in p38 MAPK signaling-related genes (TRIM67 and DAB2IP) potentially associated with hypospadias. CONCLUSION: Our study expands the phenotypic spectrum of variants affecting p38 MAPK signaling toward the involvement of hypospadias.

Analysis of BRAF V600E expression and disease-free survival in patients with ameloblastoma.

The correlation between BRAF mutation and the aggressiveness of ameloblastoma remains controversial. The aim of this study was to investigate the association of BRAF V600E expression with clinicopathological features and disease-free survival (DFS) in patients with ameloblastoma. Seventy-four conventional ameloblastoma samples were collected. Immunohistochemistry using anti-BRAF V600E antibody was performed on formalin-fixed, paraffin-embedded tissue sections. Clinicopathological characteristics and treatment outcomes were retrieved from the patient medical records. BRAF V600E immunoreactivity was detected in 50/74 cases (67.6%); 39 were strongly positive and 11 weakly. There was a significant difference in BRAF V600E expression between ameloblastoma and dental follicle (P = 0.034). However, there was no significant association of BRAF V600E expression with any clinicopathological features, including sex, age, location, duration, tumour size, radiographic appearance, cortical perforation, recurrence, and histological subtype. DFS analysis revealed that patients with BRAF-mutated ameloblastoma had a shorter median survival time (84 months vs 168 months) and lower 5-year survival rate (59% vs 67%) compared to the BRAF wild-type group; however, this was not statistically significant (P = 0.169). Moreover, logistic regression analysis revealed that treatment with enucleation was an independent risk factor for tumour recurrence (odds ratio 9.236; P = 0.028). This study demonstrated that the BRAF V600E mutation was not associated with any clinicopathological features of ameloblastoma. A trend towards earlier recurrence in tumours with BRAF mutation was observed, but this requires further investigation. Furthermore, the findings suggest that the treatment modality is an important factor in determining recurrence in ameloblastoma despite genetic alterations.

Diagnostic accuracy of immunohistochemistry compared with molecular tests for detection of BRAF V600E mutation in ameloblastomas: Systematic review and meta-analysis.

OBJECTIVE: The objective of this systematic review with meta-analysis was to critically evaluate the available data on sensitivity and specificity of IHC compared with molecular tests in the detection of BRAF V600E mutation in ameloblastomas. MATERIALS AND METHODS: This systematic review was performed based on the PRISMA statement and registered in Prospero (CRD42021259117). PubMed, Web of Science, Scopus, and Cochrane Library databases were searched for observational studies to answer the question "What is the diagnostic accuracy of immunohistochemistry compared with molecular tests for the diagnosis of BRAF V600E mutation in ameloblastomas?". Methodological quality and risk of bias assessment of the selected studies were based on the QUADAS-2. Meta-analysis based on hierarchical SROC curve model and summary measures for sensitivity and specificity were computed. RESULTS: A total of 226 records were found, but only 05 articles met the inclusion criteria, with 277 FFPE specimens of ameloblastoma included in the quantitative analysis. The sensitivity of the IHC compared to molecular tests ranged from 0.71 to 1.00, while all of the included studies showed perfect specificity (1.00). Pooled measures for sensitivity and specificity were 0.95 [95% CI 0.89, 1.00] and 1.00 [95% CI 0.95, 1.00], respectively. The diagnostic odds ratio was 4.05, and the AUC for SROC curve was calculated as 0.979. CONCLUSIONS: BRAF V600E-specific IHC using VE1 antibody showed extremely high sensitivity and specificity when compared with molecular tests in the detection of the mutation in ameloblastomas.

TREM1 fosters an immunosuppressive tumor microenvironment in papillary thyroid cancer.

The immunosuppressive microenvironment is associated with poor prognosis in papillary thyroid cancer (PTC); however, the molecular mechanisms involved are unknown. Among the triggering receptors expressed on myeloid cell (TREM) family, we found that TREM1 expression in PTC was significantly higher than that in normal tissues. TREM1 overexpression was associated with BRAFV600E profiles and advanced tumor stages. Furthermore, TREM1 mRNA expression was negatively correlated with promoter methylation status. Specifically, hypomethylation of CpG site cg06196379 in the TREM1 promoter was related with poor patient disease-free survival (DFS) and a high PTC recurrence rate. Mechanistically, TREM1 was mainly expressed in malignant epithelial cells but not in macrophages in PTC by single-cell analysis. PTC tissues with high TREM1 levels had enhanced infiltration of regulatory T cells (Tregs) and decreased infiltration of CD8+ T cells. Our study confirms that hypomethylation-mediated overexpression of TREM1 in PTC cells promotes an immunosuppressive microenvironment by enhancing Treg infiltration. We recommend the future use of therapeutic strategy targeting TREM1 for the treatment of PTC.

Long-term vemurafenib therapy in advanced melanoma patients: cutaneous toxicity and prognostic implications.

BACKGROUND: The introduction of targeted therapies for the treatment of BRAF-mutated metastatic melanoma was associated with different cutaneous adverse events (AEs). OBJECTIVES: To describe the type, frequency and severity of cutaneous AEs related to vemurafenib; to understand the association between AEs and vemurafenib efficacy in terms of median overall survival (OS) and median progression-free survival (PFS); to identify molecular characteristics of long-term responders. METHODS: This observational, retrospective, monocentric study included all consecutive patients with unresectable stage III or stage IV melanoma and BRAF V600E mutation that started treatment with vemurafenib between May 2012 and May 2014. RESULTS: 62 patients with a median age of 56 years (range 26-82) were enrolled and received vemurafenib for a median period of 7.9 months (range 0.8-63.7). Among them, 45 patients presented at least one skin AE, 12 reduced the dosage due to cutaneous toxicity, and only one firstly reduced and after stopped the therapy. No specific molecular biomarkers were detected in long-term survivors. CONCLUSIONS: Among long-term survivors, skin AEs seem to be less frequent and less severe. Results on multivariable analysis revealed that the presence of at least one G2 toxicity is a protective factor considering PFS, but not in terms of OS.

Prognostic value of total metabolic tumour volume and therapy-response assessment by [18F]FDG PET/CT in patients with metastatic melanoma treated with BRAF/MEK inhibitors.

OBJECTIVES: Target therapy with BRAF/MEK inhibitors in metastatic melanoma is characterised by a high response rate; however, acquired resistance to treatment develops in many cases. We aimed to investigate if baseline total metabolic tumour volume (TMTV) and therapy-response assessment by [18F]FDG PET/CT have a prognostic role on progression-free survival (PFS) and overall survival (OS) in patients with metastatic melanoma receiving BRAF ± MEK inhibitors. METHODS: Fifty-seven patients who performed an [18F]FDG PET/CT at baseline and on treatment were retrospectively evaluated. A Cox proportional-hazard model was used to examine associations between OS and PFS with baseline clinical/PET parameters as well as for PET response. RESULTS: According to EORTC criteria, 34 patients were classified as responders (partial/complete metabolic response [PMR/CMR]) and 23 as non-responders (progressive/stable metabolic disease [PMD/SMD]). Baseline characteristics associated with a shorter PFS were more than two metastatic organ sites and TMTV > 56 cm3; the latter was the only independent feature at multivariate analysis. Patients achieving a CMR were associated with a prolonged PFS compared with those with PMR (median PFS 42.9 vs 8.8 months; p = 0.009). Disease progression occurred in new-onset disease sites in 87.5% of CMR, 7.1% of PMR and 34.8% of PMD/SMD (p < 0.001). High baseline TMTV and lack of treatment response were independent prognostic factors for OS, stratifying patients in three different prognostic classes (median OS 6.7, 18.3 and 102.2 months, respectively). CONCLUSIONS: Baseline TMTV and metabolic response may be useful prognostic indicators for PFS and OS in patients with advanced melanoma treated with BRAF/MEK inhibitors. KEY POINTS: • In a retrospective cohort of 57 metastatic melanoma patients treated with BRAF/MEK inhibitors, a TMTV > 56 cm3 at baseline [18F]FDG PET/CT was significantly correlated with a shorter PFS and OS. • The combined use of baseline TMTV along with PET response during treatment allowed for the identification of three groups of patients with very different median OS.