Managing concurrent endometrial stromal sarcoma during pregnancy.

The co-occurrence of endometrial stromal sarcoma and pregnancy is a rarely documented occurrence, leading to a scarcity of comprehensive research and treatment guidelines in the current literature. This case is centred around a low-grade stromal sarcoma in a woman at 15 weeks of gestation. Initially presenting with left iliac fossa pain and elevated inflammatory markers, the diagnosis was suspected to be pyelonephritis, which prompted the initiation of intravenous antibiotics. Persistent symptoms prompted an MRI at 19 weeks' gestation, which revealed a mass expanding into the left internal iliac and left common iliac veins, as well as compression and invasion of the left distal ureter and associated obstructive uropathy to the level of the mass. This case highlights the diagnostic challenges and multidisciplinary management of the patient as well as the justification for supporting her wishes to continue with the pregnancy.