Imaging malignant and apparent malignant transformation of benign gynaecological disease

Common benign gynaecological diseases, such as leiomyoma, adenomyosis, endometriosis, and mature teratoma, rarely undergo malignant transformation. Benign transformations that may mimic malignancy include benign metastasizing leiomyoma, massive ovarian oedema, decidualization of endometrioma, and rupture of mature teratoma. The aim of this review is to provide a contemporary overview of imaging findings in malignant and apparent malignant transformation of benign gynaecological disease.     

Pearls and Potential Pitfalls for Correct Diagnosis of Ovarian Cystadenofibroma in MRI: A Pictorial Essay

Ovarian cystadenofibroma is a benign ovarian tumor that is characterized by a consistent percentage of masses, which remain indeterminate in ultrasonography and require magnetic resonance (MR) investigation; they may mimic borderline or malignant lesions. Three main morphologic patterns, resembling different ovarian neoplasms, can be identified in cystadenofibromas: multilocular solid lesions, unilocular cystic lesions with parietal thickening, and purely cystic masses. However, a cystoadenofibroma has typical features, such as T2-weighted hypointensity associated with no restrictions in diffusion-weighted imaging (the so-called “dark-dark appearance”) and progressive post-contrast enhancement (type I perfusion curve). The purpose of this study was to review the features of ovarian cystadenofibromas in MR imaging and to suggest pearls and pitfalls regarding their correct diagnosis.     

Evaluation of gynecologic malignancy by magnetic resonance imaging.

Currently, MR imaging has demonstrated the greatest accuracy and has potentially the greatest clinical utility for the staging of cervical carcinoma. Endometrial carcinoma also can be staged by MR imaging with reasonable accuracy, although the clinical indications for preoperative endometrial carcinoma staging are less clear. MR imaging has unparalleled capacity for the tissue characterization of adnexal disease and has demonstrated utility for diagnosis of common adnexal masses such as pedunculated leiomyoma, endometrioma, and ovarian dermoid. Its use in the evaluation or staging of ovarian, vaginal, and vulvar carcinoma has not been evaluated fully. MR imaging can demonstrate complications of radiation therapy and surgery and can distinguish most recurrent carcinomas from postradiation fibrosis. New techniques such as arrayed use of surface coils, endoluminal surface coils, fast spin-echo acquisitions, and contrast agents show promise for contributing to the already rapid pace of technologic advancement in the field of MR imaging of the female pelvis.     

MRI对合并子宫内膜病变的卵巢肿瘤的诊断价值

目的探讨MRI对合并子宫内膜病变的卵巢肿瘤的诊断价值。方法回顾性分析27例经病理证实的合并子宫内膜病变的卵巢肿瘤患者的临床特征及MRI表现。结果27例卵巢肿瘤患者中,卵巢颗粒细胞瘤6例,其中2例(2/6)合并子宫内膜增生,3例(3/6)合并子宫内膜息肉,1例(1/6)合并子宫内膜浆液性癌;卵泡膜纤维瘤15例,其中9例(9/15)合并子宫内膜增生,5例(5/15)合并子宫内膜息肉,1例(1/15)合并子宫内膜浆液性癌;卵巢子宫内膜样癌6例,其中2例(2/6)合并子宫内膜增生,4例(4/6)合并子宫内膜样癌。27例患者卵巢肿瘤的MRI特点卵巢颗粒细胞瘤表现为附件区囊实性占位,具有海绵样外观;卵泡膜纤维瘤T1WI及T2WI常呈等低信号;卵巢子宫内膜样癌常表现为盆腔内体积较大的带有壁结节的囊实性肿块,增强扫描表现为“火焰征”。结论卵巢颗粒细胞瘤、卵泡膜纤维瘤及卵巢子宫内膜样癌均可同时合并子宫内膜病变,它们的MRI表现具有一定特征性,当MRI检查发现卵巢肿瘤与子宫内膜病变并存时,根据其影像特点,能够作出较明确的诊断。     

Cystic adenomyosis with florid glandular differentiation mimicking ovarian malignancy

We report a case of cystic adenomyosis, presenting as a huge exophytic cystic mass with florid glandular differentiation. MR findings of the mass mimicked ovarian carcinoma associated with endometriosis. The presence of signal voids bridging the uterus and tumour should suggest a mass of uterine origin. Hyperintense protuberance in a hypointense loculus on T(2) weighted images may suggest benign disease. However, surgical exploration and resection is still required to exclude an ovarian malignancy.     

Ovarian carcinoma in patients with endometriosis: MR imaging findings

OBJECTIVE: Various types of malignancy can develop in patients with endometriosis. Enhancing mural nodules have been reported as an imaging characteristic of malignant transformations. We evaluated contrast-enhanced MR imaging to determine the optimum sequence to reveal mural nodules and other characteristics of malignant transformations. MATERIALS AND METHODS: We examined 10 patients with pathologically proven ovarian adenocarcinoma in endometriosis and 10 patients (the control group) with ovarian endometrioma suggestive of malignant transformation on the basis of sonographic findings. We analyzed the size and nature of the endometriomas in each patient. We compared four types of contrast-enhanced MR imaging to determine which sequence best revealed mural nodules. RESULTS: In the malignant and control groups, 80% of the cysts with findings suggestive of malignant transformation showed unilateral disease or larger endometrial cysts on the suggestive side than on the contralateral side. High signal intensity on T1-weighted images and low signal intensity on T2-weighted images relative to the myometrium were observed only in two of 10 malignant endometrial cysts and in all control cysts. All malignant endometriomas had small mural nodules with low signal intensity on T1-weighted contrast-enhanced images. Only three benign endometriomas had mural nodules and none of them enhanced. The enhancement of mural nodules was easily seen on dynamic subtraction imaging. CONCLUSION: On the basis of our findings, endometrial cysts with malignant transformation rarely show low signal intensity on T2-weighted images and usually have enhancing mural nodules. Because the enhancement of mural nodules is often difficult to evaluate on conventional T1-weighted images, dynamic subtraction imaging can be valuable.     

MR imaging of renal cell carcinoma: its role in determining cell type

Chemical shift gradient-echo MR imaging (CSI) can detect a small amount of fat as signal loss on opposed-phase images as compared with in-phase images. Cytoplasmic fat in clear cell renal cell carcinoma (RCC) or interstitial histiocytic fat in papillary cell RCC can be successfully demonstrated by this technique. T2*-weighted gradient-echo or echo-planar MR imaging can detect local susceptibility, for example, due to cytoplasmic or interstitial histiocytic hemosiderin deposition in papillary cell RCC. CSI can also show this focal susceptibility as excessive signal loss on in-phase images as compared with opposed-phase images. MR imaging can thus help predict the cell types (clear cell and papillary cell) of RCC. These findings may be important in the decision-making process in the management of patients with suspected RCC, particularly those who are not indicated for radical surgery.     

Magnetic resonance imaging of ovarian cancer arising in endometriomas

The magnetic resonance imaging (MRI) findings in 2 cases of ovarian cancer arising in an endometrioma are presented. In both cases, the cancer was evident as an enhancing mass within a blood-filled adnexal cyst. The MRI findings of an enhancing mass within a blood-filled adnexal cyst should prompt consideration of ovarian cancer arising in an endometrioma, facilitating recognition of a superimposed malignancy and potentially allowing for earlier and more efficacious treatment.     

First experiences with technetium-99m furifosmin as tumour-seeking agent in breast cancer and recurrent ovarian cancer

Recent in vitro studies suggest that technetium-99m furifosmin may have tumour-seeking properties. We analysed the diagnostic value of^99mTc-furifosmin scintigraphy in nine patients with documented carcinoma of the breast and in eight patients with continued recurrent ovarian cancer. In the breast,^99mTc-furifosmin failed to visualize the primary malignant tumour and the associated malignant lymph nodes in all patients. In contrast, multiple sites of increased tracer uptake were demonstrated in one patient with acute benign inflammatory breast disease. In four of eight patients with recurrent ovarian cancer,^99mTc-furifosmin scintigraphy demonstrated early (5 min p.i.) localized increased uptake corresponding to adhesions to the bowel as diagnosed by computed tomography, but failed to reveal further abnormalities in all patients. The present study demonstrates that furifosmin is of no value in the imaging of breast cancer and recurrent ovarian cancer. These results do not continue the pattern observed in cell culture studies and are quite in contrast to the findings of mammoscintigraphy using^99mTc-methoxyisobutylisonitrile and^99mTc-tetrofosmin.     

COVID-Related Leukoencephalopathy: Unusual MRI Features and Comparability to Delayed Post Hypoxic Ischemic Encephalopathy

COVID-19 related leukoencephalopathy can be multifactorial given the systemic effects of the viral disease. We present couple of cases with typical clinico-imaging stigmata of COVID-19 resulting in severe respiratory insufficiency. MR brain imaging revealed confluent diffuse supratentorial white matter T2 hyperintensity with restricted diffusion during the sub-acute course of the disease. The MR imaging pattern of leukoencephalopathy was non-specific but more comparable to delayed post-hypoxic leukoencephalopathy (DPHL) as also previously reported in COVID-19. Interestingly, T2 imaging showed unusual but peculiar finding of “accentuated medullary veins” in the superficial zones. No dural venous sinus thrombosis or micro-hemorrhages were present to explain “dots and stripes” due to dilated medullary veins. The patho-mechanism of this findings is not clear but may possibly be related to demyelination as DPHL has shown to be a demyelinating process. We present a review of COVID-related leukoencephalopathy with discussion on hypoxia-induced demyelinating process with accentuated medullary veins as possible associated marker.     

Computed tomography of benign ovarian masses

Although ultrasound is the primary imaging modality for evaluating benign gynecologic pelvic masses, CT may provide diagnostic information regarding ovarian masses that are discovered fortuitously. The relatively infrequent use of CT in evaluating the adnexa has resulted in a paucity of literature regarding the CT characteristics of benign ovarian masses. The CT appearances of 24 benign ovarian masses are presented. Pathologic diagnoses were ovarian cyst (nine), endometrioma (five), teratoma (three), serous cystadenoma (two), mucinous cystadenoma (two), thecoma (one), cystadenofibroma (one), and Brenner tumor (one). Benign ovarian cysts have characteristic homogeneous water density and smooth walls on CT. Single internal septations and slight wall irregularity are also common features, but soft-tissue mural or septal nodules are uncommon. Computed tomography can be diagnostic in evaluating cystic teratomas. Other benign ovarian masses exhibit a spectrum of CT appearances that is often nonspecific, and surgical or biopsy proof may be necessary to exclude malignancy.     

Malignant struma ovarii: Case report of an unusual ovarian tumor with CT imaging

Struma ovarii is categorised as a monodermal type of mature teratoma and consists primarily of thyroid tissue. It is an uncommon ovarian tumor, with non–specific clinical, and imaging findings. The majority of struma ovarii are benign and are typically associated with mature cystic teratomas. A small proportion of struma ovarii may undergo malignant transformation, with papillary carcinoma the most common type of malignancy. The criteria used to identify a malignant change in struma ovarii are identical to those used to evaluate the thyroid gland. Nevertheless, due to the rarity of struma ovarii, imaging diagnostic criteria, and subsequent management are not clearly defined. This case report describes a 41-year-old female patient who presented with rapid abdominal enlargement over a period of 1 month, accompanied by elevation of the tumor marker CA-125. Based on these clinically findings, ovarian cancer was suspected. The patient underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy. Histopathology results revealed a malignant struma ovarii.     

Discrepancy of contrast-enhanced ultrasonographic pattern with two contrast agents in steatohepatitic subtype hepatocellular carcinoma: A case report

Contrast-enhanced ultrasound (CEUS) is one of the important imaging modalities for diagnosis of hepatocellular carcinoma (HCC). Sonovue and Sonazoid are the third-generation of ultrasound contrast agents that have been commercialized and widely used in clinical applications. This study introduces the imaging differences between these two agents in vascular phases for the first time. A 54-year-old man clinical suspected liver cancer. He had chronic hepatitis B for more than 20 years. The result of alpha-fetoprotein was 36.45μg/L (normal< 20μg/L). The imaging pattern of CEUS with Sonovue was “fast-in and fast-out” performance, while the pattern of “fast-out” was absent after portal phase with Sonazoid, even in Kupffer phase. The lesion was diagnosed as lipid-rich HCC by contrast-enhanced MRI. After liver resection, pathology revealed that it was hepatocellular carcinoma contained poor-differentiated steatohepatitis subtype and moderate-differentiated microtrabecular subtype. The imaging difference mainly existed in the part of steatohepatitis subtype. Steatohepatitis subtype HCC can be showed as “fast-in and no wash-out” characteristic in Sonazoid CEUS. Though the mechanism remains not fully clarified, this different enhancing pattern may provide a potential for the supplement of the guidelines and differential of steatohepatitis subtype HCC.     

Imaging findings of primary adrenal tumors in pediatric patients

Apart from neuroblastomas, adrenal tumors are rarely seen in children. The most common adrenal tumors are adrenocortical carcinoma and pheochromocytoma. Adrenocortical carcinoma is usually a large heterogeneous, well-marginated mass with solid/cystic areas and calcifications, with poor prognosis. Most of the pheochromocytomas are benign tumors and usually show intense contrast enhancement, the pattern of which may be diffuse, mottled, or peripheral on computed tomography and magnetic resonance imaging. The purpose of this article is to evaluate primary nonneurogenic adrenal tumors.

In children, neoplastic and non-neoplastic lesions might be seen in the adrenal region. Pediatric adrenal lesions may be found incidentally, can be suspected in children that suffer endocrine, metabolic, neurological problems or with an abdominal mass. In fetal life, adrenal glands are much larger than in adults because of the existence of a prominent fetal cortex. Their prominent fetal size is also seen in early neonatal life. Ultrasonography (US) is the initial imaging technique to examine the adrenal glands in newborns. In older children, due to the physiologic atrophy of the fetal adrenal cortex, adrenal limbs are thinner than the adjacent crura of the diaphragm. Consequently, they are much more difficult to specify with US, but can be easily identified on computed tomography (CT) or magnetic resonance imaging (MRI). US is the primary modality for imaging the pediatric abdomen. CT or MRI are used as a problem-solving tool for lesion characterization, to determine the relationship to adjacent tissues, and to differentiate benign from malignant masses after initial US evaluation (1). In older children MRI should be preferred rather than CT examination. In adults, abdominal CT examinations assess tumor washout of contrast material based upon multi-phase CT, which is necessary to characterize adrenocortical masses (especially adenomas). However, pediatric CT examinations should be done in single portal venous phase to comply with “Image Gently” and “as low as reasonably achievable” (ALARA) principles.Primary adrenal tumors are classified according to their origin and function. They might originate from the medulla or cortex, and they are hyperfunctioning or nonfunctioning. Primary medullary tumors encompass a spectrum of sympathetic neuroectodermal tumors, which are neuroblastoma, ganglioneuroblastoma, ganglioneuroma, and pheochromocytoma, all of which stem from the neural crest and may take place anywhere along the sympathetic chain aside from the adrenal gland itself. Neoplasms arising from the adrenal cortex are adrenocortical carcinoma and adenoma.In the literature, few studies have reported imaging findings of pediatric adrenal tumors, including all types of involvement (i.e., benign, malignant, and metastatic) (1–3). The aim of this article is to describe the imaging findings of primary nonneurogenic adrenal tumors.     

The role of MRI in the diagnosis of endometriosis

Aim

The aim of this study is to evaluate the accuracy of the magnetic resonance imaging in diagnosis of endometriosis especially in non-apparent types as tubal and cul de sac endometriosis.

Patients and methods

MRI obtained between January 2007 and June 2009 for 34 premenopausal women complaining of dysmenorrhea, menorrhagia and infertility and the diagnosis of endometriosis were included in the differential diagnosis. T1 weighted fat saturated and T2 weighted images were done for every patient, we evaluated the MR images for the presence of T1 bright signal suggesting endometriosis. Transvaginal US was performed in two perpendicular planes for the detection of focal areas with ill defined borders or abnormal echo texture. Suspicious cases which become negative by laparoscopy were excluded from the study.

Results

MRI diagnosed endometriosis in the uterus in 18 patients, ovarian endometriosis in 13 patients, tubal in two patients, and cul de sac in one patient.

Conclusion

It is concluded that MRI is superior in the diagnosis of endometriosis than transvaginal ultrasound.     

Role of diffusion MRI and proton magnetic resonance spectroscopy in characterization of ovarian neoplasms

Introduction

Adnexal masses are a common clinical problem and considered as the leading indication for gynecological surgery. The ovary and adnexal structures are relatively difficult to image with any technology. Magnetic resonance spectroscopy (MRS) can detect metabolic changes. As molecular changes often precede morphologic alterations, sensitivity is expected to improve by MRS. Diffusion weighted magnetic resonance imaging (DW-MRI) is sensitive to molecular diffusion which is due to random microscopic translational motion of molecules (known as Brownian motion). In the event of morphologic evaluation of cystic ovarian tumors, whether benign or malignant, DW-MR imaging and calculated apparent diffusion coefficient (ADC) values would be useful for evaluation.

Purpose

The aim of this study is to evaluate the role of diffusion MRI & proton magnetic resonance spectroscopy (H-MRS) in diagnosis of ovarian neoplasms.

Subjects and methods

This study included 20 patients, their ages ranged from 20 to 72 years. In all cases, diagnosis was proven by surgical and pathological examination. Trans-abdominal ultrasound (n = 20) and trans-vaginal ultrasound (n = 11) were included in our routine protocol to obtain baseline information preceding MR examination. The routine MR examination protocol included: T1WI, T2WI, and post contrast fat suppressed T1WI. Diffusion weighted imaging (DWI) was done to all patients at b0, b500, b1000 and ADC values were calculated. MRS was performed in all cases using multi-voxel point resolved surface coil spectroscopy (PRESS sequence) for volume localization.

Results

Fourteen cases (70%) had benign ovarian masses while the remaining six cases (30%) had malignant masses. High lipid peak was detected in all three cases of mature cystic teratoma. All cases of simple serous cysts showed choline and creatine signals that were higher than the average noise level but lower than the two fold higher noise level. Sharp choline peak was detected in all malignant ovarian masses (except a case of metastases under chemotherapy) as well as the case of fibroma. Creatine signal was detected in all benign and malignant masses except two cases of mature cystic teratoma and cases of endometrioma. Lactate signal was detected only in cases of hemorrhagic cysts, mature cyst teratoma and one case of endometrioma and not obtained in any of malignant lesions except dysgerminoma. High NAA signal was detected in dysgerminoma and all three cases of mature cystic teratomas. The mean Cho/Cr ratio was significantly higher in malignant than benign ovarian masses (<0.05), there was no significant difference in mean and lowest ADC values between malignant and benign lesions.

Conclusion

Proton MRS using Cho/Cr ratio added useful information for the diagnosis of different ovarian neoplasms. Direct visual assessment of DWI of ovarian lesions is not useful in differentiating benign from malignant ovarian lesions; determining the threshold of the ADC for diagnosing cystic ovarian tumors is difficult because of their large variance. Further experience with a larger and more biologically variable range of tumors is recommended.     

Ovarian Cancer Management: the role of imaging and diagnostic challenges

Worldwide, ovarian cancer accounts for 4% of all female cancers with over 190,000 new cases diagnosed each year. The incidence rates vary considerably across the globe with the highest rates seen in Europe and the USA and low rates in Africa and Asia. Ovarian cancer has been termed a ‘silent’ killer with the majority of patients presenting with advanced disease due to the vague, non-specific nature of the presenting symptoms such as abdominal discomfort and bloating in 50%. The most important determinant of survival for ovarian cancer patients is the disease stage at diagnosis. Therefore there is a thrust for early detection and two large screening trials are currently underway in the UK and USA.Ovarian cancer is most commonly staged using the International Federation of Gynecology and Obstetrics (FIGO) surgical-pathological staging system. Imaging findings are not a formal component of the staging system but in clinical practice they play a significant role in the diagnosis and management of suspected ovarian cancer. Adnexal masses which are shown to have benign features on imaging can undergo simple excision at a local unit by a non-oncological gynaecologist. If a mass has malignant characteristics on imaging, then a radical surgical approach is indicated and this should be performed by a gynaecological oncological surgeon at a specialist cancer centre, as optimal cytoreductive surgery has been reported to improve outcome.This review article discusses the role of various imaging modalities in the initial assessment of an adnexal mass, the contribution to management planning and to the follow-up of patients with ovarian cancer.     

MRI in the Diagnosis of Endometriosis and Related Diseases

Endometriosis, a common chronic inflammatory disease in female of reproductive age, is closely related to patient symptoms and fertility. Because of its high contrast resolution and objectivity, MRI can contribute to the early and accurate diagnosis of ovarian endometriotic cysts and deeply infiltrating endometriosis without the need for any invasive procedure or radiation exposure. The ovaries, which are the most frequent site of endometriosis, can be afflicted by multiple related conditions and diseases. For the diagnosis of deeply infiltrating endometriosis and secondary adhesions among pelvic organs, fibrosis around the ectopic endometrial gland is usually found as a T2 hypointense lesion. This review summarizes the MRI findings obtained for ovarian endometriotic cysts and their physiologically and pathologically related conditions. This article also includes the key imaging findings of deeply infiltrating endometriosis.     

Magnetic resonance imaging findings of endometrioid adenocarcinoma of the ovary

PURPOSE: We assessed magnetic resonance imaging (MRI) features and clinical characteristics of ovarian endometrioid adenocarcinoma. MATERIALS AND METHODS: A total of 31 patients with 39 surgically proven ovarian endometrioid adenocarcinomas were analyzed retrospectively. Histologically, 13 lesions in 12 patients arose from proven endometriomas (group A), and 26 lesions in 19 patients did not coexist with endometrioma (group B). The morphological pattern of the lesion on MRI was classified as a solid or a cystic type: A solid type was defined as a solid component occupying more than half of the lesion; and a cystic type was a cystic lesion with one or more mural nodules. RESULTS: Altogether, 11 lesions in group A were the cystic type on MRI, whereas 24 lesions in group B were the solid type (P < 0.0001). Among the 11 cystic-type lesions in group A, the cysts of 5 lesions were hypointense on T1-weighted images, and the cysts of 6 lesions were hyperintense on T1- and T2-weighted images without "shading." The nuclear grade was higher (P = 0.0028) and the clinical stage more advanced (P = 0.0018) in group B compared to group A. CONCLUSION: MRI of ovarian endometrioid adenocarcinomas revealed two types: a solid type and a cystic type. The lesions arising from endometriomas tended to be the cystic type on MRI and have a good prognosis. Preexisting endometrioma in this entity rarely showed "shading" on T2-weighted images.     

Value of magnetic resonance imaging for the diagnosis of ovarian tumors: a review

This article reviews the value of magnetic resonance imaging (MRI) for the diagnosis of ovarian tumors especially when ultrasonography is indeterminate. Although ultrasonography is the first imaging technique used to investigate suspected pelvic masses, it has a limited capacity for tissue characterization. In addition to morphological characteristics, many tissue parameters such as T1, T2, perfusion, and diffusion contribute to signal intensity, so MRI is able to identify various types of tissue contained in pelvic masses. Magnetic resonance imaging helps to locate large solid masses and to distinguish benign from malignant ovarian tumors, with an overall accuracy of 88% to 93% for the diagnosis of malignancy. The aims of this review are 3-fold. First, we review state-of-the-art and usual MRI techniques and published findings. Second, we recall the MR features most useful for assessing the main ovarian tumors. Finally, we discuss the relevance of various features for distinguishing between benign, borderline, and invasive ovarian tumors.