This narrative review aims to clarify the role of tertiary lymphoid structures in breast cancer. We examine their development, composition, and prognostic value, and current ways of recognizing them. A comprehensive literature review was performed using the PubMed/Medline, Scopus, and EMBASE databases. A significant area of interest in breast cancer research involves targeting immune checkpoint molecules, particularly in the triple-negative subtype, where treatment options remain limited. However, existing biomarkers have limitations in accurately predicting treatment response. In this context, tertiary lymphoid structures (TLSs) emerge as a prognostic biomarker and also as a promising predictive marker for response. TLSs are ectopic lymphoid formations or neo-organogenesis that can develop after prolonged exposure to inflammatory signals mediated by chemokines and cytokines. Their presence is inversely correlated with estrogen receptor (ER) and/or progesterone receptor (PR) expression, but positively associated with a higher pathologic complete response rate and improved overall survival. In certain scenarios, TLS-positive tumors were associated with improved outcomes regardless of the presence of PDL-1 (programmed cell death ligand 1) expression or TILs (tumor-infiltrating lymphocytes).

Gastric cancer has a high incidence and mortality rate worldwide. Epidemiological, clinical, and molecular features significantly impact patient outcomes. In regions lacking a national gastric cancer registry, hospital-based registries can provide crucial data that may aid in planning therapeutic strategies for the disease. A retrospective observational cohort design was carried out in European Union (EU) and Latin American (LATAM) countries participating in the LEGACy project. Survival estimates were determined using actuarial Kaplan–Meier curves. Comparison was carried out with the log-rank test, and differences were considered statistically significant for P values ≤0.05. A total of 689 patients diagnosed with gastric cancer from November 2018 to November 2019 were included. Both cohorts had the body as the most common site reported (34.4% for EU and 51% for LATAM). The most used method for staging was computed tomography for both cohorts, although 6.9% of the LATAM population had positron emission tomography/computed tomography instead. Intestinal histological subtype was the most common (41.9% and 46.3% reported by EU and LATAM), while diffuse subtype was 44.9% for the LATAM and 21.3% for the EU population. Among patients tested for human epidermal growth factor receptor 2 (HER2), 12.5% were positive in the EU cohort and 13.8% in the LATAM cohort. For both cohorts, the most common site of human epidermal growth factor receptor 2 positivity was the gastroesophageal junction. Systemic treatment with curative intention was indicated in 50.7% in the EU cohort and 46.4% of the LATAM cohort. The most frequent scheme indicated for both the localized and the advanced setting was platinum-based (42.6% and 84.8% for EU and LATAM). Considering both cohorts, only 14.4% of the patients received second-line treatment, and 3% received a third-line treatment. After using Cox regression analysis, no difference in overall survival was reported, with a median of 10.9 months. Despite the limitations of hospital-based registry analysis, our study has provided valuable insights into clinical characteristics and treatment approaches of EU and LATAM populations.

PURPOSE: This study aims to describe genomic characteristics of patients with metastatic prostate cancer (mPC). PATIENTS AND METHODS: This study is a retrospective, multicenter cohort study of patients with mPC and reports on genomic testing. Patients were included from 12 academic centers in five countries. RESULTS: A total of 349 patients with PC were included in this study. Most patients (209, 59.9%) were de novo metastatic. Genomic analysis was performed in 233 (66.6%) patients in the metastatic castration-resistant prostate cancer (mCRPC) setting, and only 115 (32.8%) patients had a tumor evaluation in the metastatic hormone sensitive prostate cancer scenario. The evaluation of somatic and/or germline mutations was performed through multigene panel analyses in 290 (83.09%) patients, and next-generation sequencing of BRCA1 and BRCA2 genes was performed in 59 (16.91%) patients. Analyzing the mCRPC subgroup, with a median follow-up of 15.6 months (IQR, 14-19.06), the median progression-free survival (PFS) was not reached (NR) and the PFS at 16 months was 58.7% (95% CI, 50.8 to 67.8). When comparing patients with BRCA mutations with those who are not BRCA -mutated in the mCRPC scenario, the median PFS was NR (95% CI, 14 to NR) and 26.3 months (95% CI, 16.7 to 36.5; P = .2), respectively. Two of six patients with BRCA mutations were treated with targeted therapies (poly-ADP-ribose polymerase inhibitors). CONCLUSION: Our study, to the best of our knowledge, represents one of the larger data sets for somatic testing in patients with PC in Latin America (LATAM). It adds valuable information to the growing body of knowledge about the genomic landscape of advanced PC in real-world daily practice scenarios in LATAM countries, which are not always well-represented in large-scale randomized clinical trials.

Background/Objectives: The BRAF-mutation is a poor prognostic factor in colorectal cancer (CRC). There is a need for real-world data in low-middle-income countries regarding clinical characteristics, outcomes, and treatment strategies. This study aims to describe progression-free survival (PFS) and in the first- and second-line setting and sequences of treatment regimens. Methods: We retrospectively analyze patients from ten oncology centers in Argentina, diagnosed with BRAF^V600E-mutated advanced CRC between January 2014 and July 2023. Results: A total of 161 patients with metastatic CRC and BRAF^V600E-mutation. The median age was 58.5 (IQR 47–69), and 21.7% were MMR-deficient (dMMR). Of these patients, 93.8% received first-line treatment. With a median follow-up of 23 months (95% CI 16.5–33.4 months), the median PFS was 9 months (95% CI 7.4–10.5 months). The most common regimen in first line setting was doublet chemotherapy plus anti-VEGF for 49% of the patients. Twenty-six percent of the patients received BRAF inhibitors in the second-line setting, with a median PFS of 5.2 months (95% CI 4.9—NR); the overall response rate (ORR) was 10.5%. Conclusions: This study represents, to the best of our knowledge, the largest published real-world cohort of BRAF^V600E-mutated CRC in Latin America. The heterogeneity of the treatments reflects the existence of barriers to access to high-cost drugs in our country. Cooperative efforts are needed to understand the particular characteristics of this subgroup of patients.

Targeted therapies in neoadjuvant treatment for gastroesophageal cancer Berenice Freile, Andrés Rodriguez, Greta Catani, Marcos Bortz, Luisina Bruno, Juan

Background/Objectives: BRAF-mutation is a poor prognostic factor in colorectal cancer (CRC). There is a need for real-world data in low-middle-income countries regarding clinical characteristics, outcomes, and treatment strategies. This study aims to describe progression free survival (PFS) and overall survival (OS) in the first-line setting, and sequences of treatment regimens. Methods: We retrospective analyze patients from ten oncology centers in Argentina, diagnosed with BRAFV600E-mutated advanced CRC between January 2014 and July 2023. Results: A total of 161 patients with metastatic CRC and BRAFV600E-mutation. The median age was 58.5 (IQR 47-69) and 21.7% were MMR-deficient (dMMR). 93.8% of the patients received first-line treatment. With a median follow-up of 23 months (95% CI 16.5 - 33.4 months), the median OS was 20.6 months (95% CI 18.4 - 29 months) and PFS 9 months (95% CI 7.4 - 10.5 months). The most common regimen was doublet chemotherapy plus anti-VEGF in 49%. 26% received BRAF inhibitors in second line setting. Conclusions: This study represents, to the best of our knowledge, the largest published real-world cohort of BRAFV600E-mutated CRC in Latin America. The heterogeneity in treatments reflect the existence of barriers to access high-cost drugs in our country. Cooperative efforts are needed to understand the particular characteristics of this subgroup of patients.