{"paper_id":"d417ca49-31dc-450f-9a31-bb354c34ca93","body_text":"A 51-year-old nulliparous woman was referred to our department for an MRI scan of the\npelvis in the work-up of pathologically proven cervical cancer. A HPV (humane\npapilloma virus) DNA test was positive for high-risk HPV types. Pathological\nanalysis of a cervical biopsy showed poorly differentiated squamous cell carcinoma.\nThe patient had a personal history of left renal agenesis, a presumed Müllerian\nduct anomaly, and surgery for endometriosis. At our department, the routine scanning\nprotocol for cervical cancer staging consists of sagittal, para-axial, and\nparacoronal T2 HASTE images adjusted to the cervical axis and axial\ndiffusion-weighted images. Based on this MRI exam, the tumor was locally staged as\ncT2bN1. Treatment consisted of surgical removal of a large external iliac adenopathy\nfollowed by concomitant radio-chemotherapy.\nIn this patient, MRI also confirmed the presence of a uterine anomaly (Figure  1 ). The left uterine horn contained a distinct\ncavity (*) and junctional zone (line) that were separated from the right horn and\ncorpus by a layer of myometrial tissue (white dashed line). In the right uterine\nhorn, the junctional zone was focally thickened. A small amount of fluid with a\nT2-hypointense component was also seen in the recto-uterine pouch (arrow).\nAdditionally, a complex thick-walled cystic mass was found in the left iliac fossa,\nadjacent to the left uterine horn. To further characterize this unknown lesion,\naxial T1 images with fat saturation were made (Figure  2 ). A distinct T1 hyperintense and T2 hypointense layer was seen within\nthis mass (arrows).\nBased on these observations, the diagnosis of right unicornuate uterus with\nnoncommunicating left cavitary horn was made. The junctional zone thickening was\ncompatible with adenomyosis. The complex cystic mass was consistent with\nendometrioma. A small amount of hemoperitoneum was the final important secondary\nfinding.\n\nThe female reproductive organs develop during the sixth week of gestation, when the\npaired Müllerian (or paramesonephric) ducts fuse to create the uterus, cervix,\nand upper two-thirds of the vagina. Unicornuate uterus is a result of abnormal or\nfailed development of one of the Müllerian ducts. Unilateral renal agenesis is\nthe most frequently associated urinary tract abnormality [ 1 ].\nFour subtypes of unicornuate uterus have been described, based on the presence or\nabsence of a rudimentary uterine horn, which may or may not communicate with the\nnormal horn. If present, functional endometrial tissue within a rudimentary horn\nputs the patient at higher risk for endometriosis, hematometra, and hematosalpinx,\nas well as adenomyosis. Fetal implantation can occur in a noncommunicating\nrudimentary horn, but it will generally result in a life-threatening uterine\nrupture. Therefore, the correct diagnosis of this entity has important clinical\nimplications, especially in young patients with a desire for pregnancy.\nMRI, with its excellent soft tissue contrast and complete lack of radiation exposure,\nallows accurate diagnosis of all subtypes of unicornuate uterus. Unicornuate uterus\nwith cavitary noncommunicating horn can be classified as a Müllerian duct\nanomaly type A1b, according to the American Fertility Society. Differential\ndiagnosis includes adnexal mass or pedunculated uterine fibroma.","source_license":"CC-BY-4.0","license_restricted":false}