Her Royal Highness Princess Chulabhorn will be admitted to Vichaiyut Hospital on Friday for a biopsy.
In a statement released on Thursday evening, the Royal Household Bureau said the princess was sick. A team of doctors at the hospital detected a lump in her neck and a biopsy was required.
The princess had a stomach ache and felt nauseous as a result of an inflamed pancreas, which required continual checkup and treatment, the statement said.