Mature Cystic Teratoma Ovary Masquerading as Abdominal Malignancy—Diagnostic Challenges and Review of Literature: A Case Report

We present the case of a 23-year-old unmarried female who experienced dull lower abdominal pain for 1 month, along with a midline mass.Notably, her carbohydrate antigen 19.9 (CA 19.9) levels were significantly elevated, which initially raised concerns about a gastrointestinal mass.However, further evaluation, including a magnetic resonance imaging (MRI), revealed a midline mass that appeared to originate from the left adnexa.Surgical exploration followed by histopathological analysis confirmed that the mass was a mature cystic teratoma of the ovary.This case underscores the importance of considering ovarian pathology, even when elevated tumor markers suggest gastrointestinal involvement.