In our study of 51 primary nodular melanomas and 18 paired metastases, we found mutations in BRAF (codon 600, previously denoted 599) in 15 primary tumors (29%) and eight metastases (44%).
Therefore, we established a large collection of patient-derived xenografts (PDXs), derived from BRAF(V600E), NRAS(Q61), or BRAF(WT)/NRAS(WT) melanoma metastases prior to treatment with BRAF inhibitor and after resistance had occurred.
In this study, the occurrence and percentage of the BRAFV600E mutated allele was not preferentially associated with the development of metastases and the average mutated allele percentage decreased as the tumor progresses from the primary site to the lymph node metastatic sites.
Here we analyse 20 BRAF(V600)-mutant melanoma metastases derived from 10 patients treated with the combination of dabrafenib and trametinib for resistance mechanisms and genetic correlates of response.
The mutant allele frequency of KRAS in metachronous metastases was higher in 6 cases (mean difference =% 25.5% (range, 9.5%-58.0%)) and lower in 3 cases (mean difference = 9.3% (range, 8.0-10.0%) compared with each of their primary tumors.
The alterations of p16 gene may play a major role in malignancy and development and metastases of buccal carcinoma and may be an excellent marker of aggressive clinical behavior.
At multivariable analysis, significant association with pathological response was found for number of resected metastases (p = 0.015) and bevacizumab allocation (p < 0.001), while KRAS mutation showed only a trend.
The utility of immunohistochemistry (IHC) as an alternative approach for detection of BRAF(V600E) in the thoracic metastases of sporadic mCRC patients has not been evaluated until now.
In our study, 43 primary cutaneous melanoma and 30 metastases were screened for CTNNB1 exon 3 mutations by using a denaturing gradient gel electrophoresis technique and sequencing. beta-Catenin mutations were found in 2 primary melanomas and 1 metastatic melanoma and were not correlated with nuclear accumulation of beta-catenin in these cases.
Most sporadic gastrointestinal stromal tumors (GISTs) occur solitary, whereas a multicentric appearance is suspicious for a familial or syndromal setting such as with germline mutations of proto-oncogene tyrosine protein kinase Kit (KIT) or platelet derived growth factor receptor alpha (PDGFRA), or even for metastases.
Discordance in BRAF mutation status was found only in four patients, involving all three patients in whom sentinel lymph node (SLN) metastases were sampled.
We analyzed 18 formalin-fixed, paraffin-embedded ONB specimens (12 primary tumors and six recurrences or metastases) from 14 patients for p53 alterations using immunohistochemistry for p53 and WAF1 together with topographic genotyping (selection of minute tissue targets from unstained sections, PCR [polymerase chain reaction] amplification of exons 5-8 followed by direct DNA sequencing).
Patients were matched according to somatic <i>BRAF</i>V600E mutation (80 BRAF+ and 80 BRAF- patients) and to the presence (LN+, 40 patients each group) or absence (LN, 40 patients each group) of neck lymphnode metastases.
Overall median survival time (MST), stratified for variables, including BRAFV600E mutation and eligibility for treatments with new immunotherapy drugs, was retrospectively assessed in 41 patients with pelvic melanoma loco regional metastases.
The following algorithm was applied: "(colorectal OR rectal OR colon OR colonic) AND (liver OR hepatic) AND (metastasis OR metastases) AND (gene OR mutation OR KRAS OR BRAF OR SMAD4 OR RAS OR TP53 OR P53 OR APC OR PI3K OR MSI OR EGFR OR MACC1 OR microsatellite)."
Statistical significance was assumed at P < 0.05 RESULTS: The metastases in EGFR-mutant adenocarcinoma had lower SUV max than EGFR wild-type adenocarcinoma (nodal SUV max 3.4 vs 5.5, distant metastasis SUV max 3.4 vs 4.7, respectively; both P < 0.001).
During 3 years of follow-up, 2 patients whose peripheral blood had carcinoembryonic antigen and CD44 variant mRNA also had distant metastases (lung or spleen).
The status of the HER2 (ERBB2) gene in breast cancer is not static and may change among the primary tumor, lymph node metastases, and distant metastases.
Heterogeneity of KRAS status consisted in KRAS mutated in (i) the primary tumour but not in its synchronous metastasis, (ii) the metastasis but not in the primary tumour, (iii) the pelvic recurrence but not in the primary tumour, (iiii) some metastases and not in others from the same patient.