Pathologies of the uterine endometrial cavity: usual and unusual manifestations and pitfalls on magnetic resonance imaging

Abstract

The endometrial cavity may demonstrate various imaging manifestations such as normal, reactive, inflammatory, and benign and malignant neoplasms. We evaluated usual and unusual magnetic resonance imaging (MRI) findings of the uterine endometrial cavity, and described the diagnostic clues to differential diagnoses. Surgically proven pathologies of the uterine endometrial cavity were evaluated retrospectively with pathologic correlation. The pathologies included benign endometrial neoplasms such as endometrial hyperplasia and polyp, malignant endometrial neoplasms such as endometrial carcinoma and carcinosarcoma, endometrial-myometrial neoplasm such as endometrial stromal sarcoma, pregnancy-related lesions in the endometrial cavity such as gestational trophoblastic diseases (hydatidiform mole, invasive mole and choriocarcinoma) and placental polyp, myometrial lesions simulating endometrial lesions such as submucosal leiomyoma and some adenomyosis, endometrial neoplasms simulating myometrial lesions such as adenomyomatous polyp and endometrial lesions arising in the hemicavity of a septate/bicornate uterus, and fluid collections in the uterine cavity (hydro/hemato/pyometra). It is important to recognize various imaging findings in these diseases, in order to make a correct preoperative diagnosis.

Functional Images Reflect Aggressiveness of Endometrial Carcinoma: Estrogen Receptor Expression Combined with 18F-FDG PET

“…The cutoff 18 F-FDG-to-18 F-FES ratio of 0.5 and the 18 F-FDG SUV of 2.0 could differentiate lowrisk carcinoma from hyperplasia, and all malignancies were correctly distinguished from benign lesions, with no falsepositive findings and 100% accuracy. Some characteristic MRI findings of benign endometrial lesions such as endometrial hyperplasia and polyps were reported previously (18,19). Those specific findings are occasionally detected in the case of relatively large tumor volume, whereas it is difficult to differentiate small-sized endometrial hyperplasia from stage Ia carcinoma.…”

Diagnostic accuracy of the apparent diffusion coefficient in differentiating benign from malignant uterine endometrial cavity lesions: initial results

“…Previous reports have demonstrated the advantages of MR imaging in visualizing endometrial lesions and in the differential diagnosis [18][19][20][21][22]. Meanwhile, some of the endometrial cavity lesions cannot be diagnosed via endometrial cytology or endometrial curettage because sampling is difficult to detect [18], and they are incidentally found at the MR examination of ovarian tumor.…”

“…Some diseases of the endometrial cavity can be diagnosed via endometrial cytology or endometrial curettage; however, others are difficult to detect, and characteristic imaging findings are helpful in diagnosis [18]. Previous reports have demonstrated the usefulness of MR imaging techniques such as contrast-enhanced dynamic imaging for differentiating abnormalities of the uterine endometrial cavity [18][19][20][21][22], while there are a few studies about the utility of DW imaging for gynecological imaging [10,[23][24][25][26][27][28][29]. In the uterine cervix, ADC measurement potentially enables differentiation between normal and cancerous tissue [10]; however, to the best of our knowledge, no reports have demonstrated the utility of ADC measurement for differential diagnosis in the uterine endometrial cavity lesions.…”

Differentiation of benign and malignant uterine corpus tumors by using proton MR spectroscopy at 3T: preliminary study

“…Various benign and malignant tumours in the endometrial cavity, such as endometrial polyp, endometrial hyperplasia and endometrial cancer may show similar magnetic resonance (MR) manifestations [1][2][3]. However some diseases can be diagnosed via endometrial cytology or endometrial curettage, conclusive pathological diagnosis is not always available.…”