Infiltrative endometriosis without endometrioma: A case report and imaging findings mimicking a bladder malignancy

Endometriosis affects 10%-15% of women of childbearing age, but the incidence can be as high as 90% in those with chronic pelvic pain. Endometriosis is categorized into ovarian endometriomas, superficial peritoneal implants, and deep infiltrating endometriosis. In this case report a 40-year-old woman gravida 1, para 1 with a history of hysterectomy in Mexico presented with chronic abdominal pain and severe hematuria. Magnetic resonance imaging revealed an infiltrative pelvic mass involving the bladder concerning for a neoplasm that demonstrated subtle hyperintense components on T1-weighted images. The diagnosis of infiltrative endometriosis was established following cystoscopy and tissue sampling. This case highlights the importance of considering endometriosis in the differential for patients with pelvic masses, and recognizing potential features that could suggest the diagnosis.