Neoadjuvant and Adjuvant Therapy Approaches to Gastric Cancer

Opinion statement Gastric cancer is an aggressive malignancy, requiring a multimodality approach to achieve optimal curative rates even when the disease is amenable to surgical resection. Neoadjuvant and adjuvant approaches differ across the globe—a preference for peri-operative chemotherapy exists in Europe, in contrast to the adoption of adjuvant chemotherapy in Asia and adjuvant chemoradiotherapy in North America. There are nuances and limitations associated with each therapeutic strategy and an understanding of these distinct approaches is integral to judicious clinical application of the available data. Although a multimodal approach provides a clear survival benefit above a surgical-only approach, data report low completion rates of adjuvant therapy components and strongly suggest a need to refine patient selection particularly for ongoing treatment in the post-operative period. This may be achieved using a risk-stratified strategy. Hence, there is a need to transition from a generalised approach to a multimodality treatment towards one guided by individual patient clinical features and biomarker profiles in order to improve tolerability and patient outcomes irrespective of geographical variation in clinical practice. While the evidences supporting molecular features such as microsatellite instability and predictive gene signatures are provocative, prospective validation is required before these can be confidently used to direct clinical decision-making.