Whether gastric cancer in young adults differs from gastric cancer in older patients has been a controversial issue. It has long been suspected that young patients with gastric cancer have different biological features with a more aggressive course of disease and a poorer prognosis than older patients. This, however, has not been firmly substantiated. We report on the clinical course of four patients (three female and one male) with locally advanced (n = 1) or metastasized (n = 3) non-resectable gastric cancer diagnosed under the age of 29 years (23, 25, 27, 28 years). Prior to diagnosis, all three women had recently been pregnant (1-22 months). Diagnosis was endoscopically biopsy-proven and staging work-up was performed by primary explorative surgery (n = 1), laparoscopy and explorative surgery (n = 1) or CAT scan and ultrasound (n = 2). The delay between initial symptoms and diagnosis was 8-22 weeks (median, 10 weeks). The histology was signet-ring cell (n = 2) or undifferentiated (n = 2) gastric cancer. All patients had the diffuse type of gastric cancer according to Lauren. Patients were treated with the FLAP polychemotherapy regimen consisting of leucovorin, 5-fluorouracil, doxorubicin and cisplatinum, as previously reported. The best response after chemotherapy was partial in two patients. Two patients showed progressive disease. Secondary surgery was performed in three responding patients (one of them responded only locally). One patient achieved no evidence of disease after complete tumor resection (R0). In two patients surgery was palliative (R2/exploration). Three patients died 6, 4 and 8 months after diagnosis. One patient is still alive. In our series, very young adults with gastric cancer had adverse clinical and pathological features. In accordance with other reports, we observed a predominance of female patients and a possible association with recent pregnancies. Though the delay between the first symptoms and diagnosis in our patients was no different from that reported for older patients, special emphasis should be given to prompt referral and diagnostic investigations, ensuring the diagnosis of gastric cancer early in the course of disease.