Gastric cancer (GC) represents a serious health problem on a global scale. Despite some recent advances in the field, the prognosis in metastatic GC remains poor. Even in localized disease the adjunctive therapies improve overall survival (OS) by only approximately 10%. A better understanding of molecular biology, which would lead to improved treatment options, is needed and is the basis for this review. Many potential biomarkers of prognostic significance have been identified, including ALDH, SHH, Sox9, HER2, EGFR, VEGF, Hippo/YAP, and MET. However, inhibition of only HER2 protein has led to a modest survival benefit. A new approach to GC treatment, which is a disease influenced by inflammation, is the exploitation of the immune system to fight disease. Two interesting targets/prognostic markers that bear further investigation in GC are PD1 and PDL, particularly given their success in the treatment of other inflammation/immune-associated malignancies.
Elena Elimova, Roopma Wadhwa, Hironori Shiozaki, Kazuki Sudo, Jeannelyn S. Estrella, Brian D. Badgwell, Prajnan Das, Aurelio Matamoros Jr, Shumei Song, and Jaffer A. Ajani
Derek J. Erstad, Mariela Blum, Jeannelyn S. Estrella, Prajnan Das, Bruce D. Minsky, Jaffer A. Ajani, Paul F. Mansfield, Naruhiko Ikoma, and Brian D. Badgwell
Background: The optimal number of examined lymph nodes (ELNs) and the positive lymph node ratio (LNR) for potentially curable gastric cancer are not established. We sought to determine clinical benchmarks for these values using a large national database. Methods: Demographic, clinicopathologic, and treatment-related data from patients treated using an R0, curative-intent gastrectomy registered in the National Cancer Database during 2004 to 2016 were evaluated. Patients with node-positive (pTxN+M0) disease were considered for analysis. Results: A total of 22,018 patients met the inclusion criteria, with a median follow-up of 2.2 years. Mean age at diagnosis was 65.6 years, 66% were male, 68% were White, 33% of tumors were located near the gastroesophageal junction, and 29% of patients had undergone preoperative therapy. Most primary tumors (62%) were category pT3–4, 67% had a poor or anaplastic grade, and 19% had signet features. Clinical nodal staging was inaccurate compared with staging at final pathology. The mean [SD] number of nodes examined was 19 . On multivariable analysis, the pN category, ELNs, and LNR were independently associated with survival (all P<.0001). Using receiver operating characteristic (ROC) analysis, an optimal ELN threshold of ≥30 was established for patients with pN3b disease and was applied to the entire cohort. Node positivity and LNR had minimal change beyond 30 examined nodes. Stage-specific LNR thresholds calculated by ROC analysis were 11% for pN1, 28% for pN2, 58% for pN3a, 64% for pN3b, 30% for total combined. By using an ELN threshold of ≥30, prognostically advantageous stage-specific LNR values could be determined for 96% of evaluated patients. Conclusions: Using a large national cancer registry, we determined that an ELN threshold of ≥30 allowed for prognostically advantageous LNRs to be achieved in 96% of patients. Therefore, ≥30 examined nodes should be considered a clinical benchmark for practice in the United States.