The Evolution of Clinically Aggressive Triple-Negative Breast Cancer Shows a Large Mutational Diversity and Early Metastasis to Lymph Nodes.

In triple-negative breast cancer (TNBC), only 30% of patients treated with neoadjuvant chemotherapy achieve a pathological complete response after treatment and more than 90% die due to metastasis formation. The diverse clinical responses and metastatic developments are attributed to extensive intrapatient genetic heterogeneity and tumor evolution acting on this neoplasm. In this work, we aimed to evaluate genomic alterations and tumor evolution in TNBC patients with aggressive disease. We sequenced the whole exome of 16 lesions from four patients who did not respond to therapy, and took several follow-up samples, including samples from tumors before and after treatment, as well as from the lymph nodes and skin metastases. We found substantial intrapatient genetic heterogeneity, with a variable tumor mutational composition. Early truncal events were MCL1 amplifications. Metastatic lesions had deletions in RB1 and PTEN, along with TERT, AKT2, and CCNE1 amplifications. Mutational signatures 06 and 12 were mainly detected in skin metastases and lymph nodes. According to phylogenetic analysis, the lymph node metastases occurred at an early stage of TNBC development. Finally, each patient had three to eight candidate driving mutations for targeted treatments. This study delves into the genomic complexity and the phylogenetic and evolutionary development of aggressive TNBC, supporting early metastatic development, and identifies specific genetic alterations associated with a response to targeted therapies.

Comprehensive Genomic Profile of Heterogeneous Long Follow-Up Triple-Negative Breast Cancer and Its Clinical Characteristics Shows DNA Repair Deficiency Has Better Prognostic.

Triple-negative breast cancer (TNBC) presents a marked diversity at the molecular level, which promotes a clinical heterogeneity that further complicates treatment. We performed a detailed whole exome sequencing profile of 29 Mexican patients with long follow-up TNBC to identify genomic alterations associated with overall survival (OS), disease-free survival (DFS), and pathologic complete response (PCR), with the aim to define their role as molecular predictive factors of treatment response and prognosis. We detected 31 driver genes with pathogenic mutations in TP53 (53%), BRCA1/2 (27%), CDKN1B (9%), PIK3CA (9%), and PTEN (9%), and 16 operative mutational signatures. Moreover, tumors with mutations in BRCA1/2 showed a trend of sensitivity to platinum salts. We found an association between deficiency in DNA repair and surveillance genes and DFS. Across all analyzed tumors we consistently found a heterogeneous molecular complexity in terms of allelic composition and operative mutational processes, which hampered the definition of molecular traits with clinical utility. This work contributes to the elucidation of the global molecular alterations of TNBC by providing accurate genomic data that may help forthcoming studies to improve treatment and survival. This is the first study that integrates genomic alterations with a long follow-up of clinical variables in a Latin American population that is an underrepresented ethnicity in most of the genomic studies.

Safety and Cost-Effectiveness in Thyroidectomy Using the HARMONIC Scalpel Compared to Traditional Hemostasis: A Controlled Clinical Assay.

INTRODUCTION: The aim of this clinical control trial is to analyze the cost-effectiveness and to understand the efficacy of the HARMONIC FOCUS®+ (Ethicon Inc., Somerville, New Jersey) scalpel as the only system to cut and coagulate in thyroidectomy. MATERIALS AND METHODS: One hundered patients of the thyroid clinic of the Mexico City General Hospital were included. All patients underwent surgery and were divided into two randomized groups. In Group 1, the HARMONIC scalpel was the only device used for cut and coagulate (50 patients), and in Group 2 clamp, tie, and electrocautery (50 patients) were used. Surgical bleeding, operative time, complications, diagnosis, thyroid size, and hospital stay were evaluated in both groups. The statistical analysis was done using central trend measurements, Student's t-, chi-squared, and Fisher's exact test, with a significance level of p < 0.05. The cost-effectiveness analysis was completed by determining the total cost of the surgical procedure per hour in US dollars, and the evolution to compare efficacy will be the number of re-interventions due to postoperative bleeding. RESULTS: The use of the HARMONIC scalpel in thyroid surgery had the same results as the traditional method when comparing complications, reoperation, hospital stay, and hypoparathyroidism. In total thyroidectomy patients, the bleeding in Group 1 was 55.16ml ( ± 32.97) and 85.4ml ( ± 69.41) in Group 2 , p=0.034. Operative time in Group 1 was 74.6 minutes (± 23.39) and 104.09 minutes (± 34.66) in Group 2, p= 0.0001. In both groups, there were no statistical differences in lobectomy. Cost-effectiveness analysis implies an adequate hemostasis if we are using a hemostatic device, and above all, the avoidance of a re-intervention due to hematoma, and the cost-effectiveness with regard to the re-intervention as a result of a hematoma implies that $161 US more is spent for each re-intervention. CONCLUSION: The utilization of the HARMONIC scalpel device is similar to the traditional technique of ligature and knots as far as cost-effectiveness is concerned, due to the fact that the greater expense of the device is compensated by the lower expense in time and surgical re-intervention.