{Reference Type}: Case Reports {Title}: Cranial hypertrophic pachymeningitis with myelodysplastic syndrome. {Author}: Kikuchi S;Hayashi T;Nitta H;Kamihara Y;Wada A;Minemura T;Nabe Y;Murakami J;Nakatsuji Y;Sato T; {Journal}: Heliyon {Volume}: 10 {Issue}: 12 {Year}: 2024 Jun 30 {Factor}: 3.776 {DOI}: 10.1016/j.heliyon.2024.e32973 {Abstract}: Hypertrophic pachymeningitis (HP) is a rare inflammatory disease characterized by thickening of the dura mater. HP develops with several inflammatory diseases. Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis and IgG4 related disease are reported as 2 major causes. With hematologic diseases, only 3 cases have been reported. We report the case of myelodysplastic syndrome (MDS) developing HP. Our case provides a thought-provoking hypothesis regarding the potential relationship between MDS and HP.