Triplication of 1q is a very rare chromosomal abnormality in hematologic malignancies, and it has been related to Fanconi anemia. The clinical significance of this abnormality is unknown. We report here on a 55-year-old female patient who had myelodysplastic syndrome (refractory anemia with excess blasts) with triplication of 1q and trisomy 8 as the clonal cytogenetic abnormalities, as determined by bone marrow cytogenetic analysis. However, there were no clinical manifestations of Fanconi anemia or any chromosomal instability according to the peripheral blood chromosomal breakage testing. The patient developed early gastric carcinoma (poorly differentiated adenocarcinoma with a signet ring cell component) eight months later. She continuously had pancytopenia with dysplastic features, but this showed no evidence of evolving to leukemia or any relapse of the gastric carcinoma over a 2 year follow up.