TTD expert consensus on emesis in gastric cancer: evidence-based strategies for prevention and treatment.

Emesis is a common complication in patients with gastric cancer (GC), resulting from both tumor progression and adverse events of antineoplastic therapies. It is estimated that up to 70% of patients experience nausea and vomiting, significantly impacting quality of life. Symptoms can lead to dehydration, malnutrition, fatigue, and emotional disturbances like anxiety and depression. Etiological factors fall into two categories. First, neoplasia-related mechanisms-gastric outlet obstruction, gastroparesis due to autonomic dysfunction, invasion of adjacent structures, presence of peritoneal carcinomatosis or malignant ascites-contribute to gastric emptying disorders. Second, antineoplastic treatments-including chemotherapy, radiotherapy, and targeted therapies-carry an inherent inducing emesis risk and can cause acute, delayed, anticipatory, breakthrough, or refractory emesis. International guidelines from the American Society of Clinical Oncology (ASCO), European Society for Medical Oncology (ESMO), Multinational Association of Supportive Care in Cancer (MASCC), and National Comprehensive Cancer Network (NCCN) recommend combination regimens that include 5-hydroxytryptamine type 3 receptor antagonist (anti-5-HT3), dexamethasone, neurokinin-1 receptor antagonists (anti-NK1), and, occasionally, olanzapine. Prophylaxis should be tailored to the emetic risk of the treatment and the individual characteristics of the patient, like age, sex, and pharmacogenomic factors. Pharmacological strategies should be complemented with non-pharmacological interventions to enhance therapeutic efficacy and alleviate symptoms. This consensus guide from the Spanish Cooperative Group for the Treatment of Digestive Tumours (TTD) highlights the importance of multidisciplinary and individualized approaches to managing emesis associated with GC. Evidence-based therapeutic algorithms are essential to achieving these goals.