Ida announced his decision on social media (thanks, VGC), stating that although he had already come up with ideas for the upcoming game, he will pass these on to others while he receives treatment. Koji Igarashi, long-time producer of the Castevania series, reposted this message to express his sadness while wishing Ida a quick recovery.
Shuntaro Ida - "I, Shutaro, also known as Curry Boy and Curry Sage, have been diagnosed with cancer and have now begun my battle with the disease. I had already started discussing the sequel to Bloodstained and I have various ideas for the game. From now on, I will hand over this work to others. Thank you for your support."
Koji Igarashi - "Up until now, the DS [Castlevania] series and Bloodstained have been produced primarily by director Shutaro. They can truly be called his works. It is a great blow that he is stepping away from the project, but we will do our best to make up for this. We hope that he will recover soon so we can work together again."
Ida has worked on several Castlevania titled before joining Igarashi to work on Bloodstained. He contributed greatly to the DS trilogy, consisting of Dawn of Sorrow, Portrait of Ruin, and Order of Ecclesia, but also worked alongside Hideo Kojima on Metal Gear Solid V: The Phantom Pain as a lead programmer. Switch players can now experience the DS Castlevania trilogy via the recently-released Castlevania Dominus Collection.
We here at Nintendo Life wish Shuntaro Ida the very best and a swift recovery.