MR imaging and CT of the female pelvis: radiologic-pathologic correlation

Identification of dirty necrosis in colorectal carcinoma based on multiphoton microscopy

Dirty necrosis within glandular lumina is often considered as a characteristic of colorectal carcinomas (CRCs) that is a diagnostically useful feature of CRCs with DNA microsatellite instability (MSI). Multiphoton microscopy (MPM), which is based on the second-harmonic generation and two-photon excited fluorescence signals, was used to identify dirty necrosis. Our results demonstrated that MPM has the ability to exhibit the microstructure of dirty necrosis and the signal intensity as well as an emission spectrum that can help to differentiate dirty necrosis from cancer cells. These findings indicate that MPM may be helpful in distinguishing MSI colorectal carcinoma via the identification of dirty necrosis.

Endometrial carcinoma: MR staging and causes of error

PURPOSE

This study was undertaken to prospectively determine the diagnostic capabilities of magnetic resonance (MR) imaging in detecting myometrial and cervical invasion and lymph node involvement in endometrial carcinoma and to identify the causes of errors in staging endometrial carcinoma.

MATERIALS AND METHODS

Twenty consecutive patients with a histological diagnosis of endometrial carcinoma underwent preoperative MR imaging. MR findings were compared with surgical staging, considered as the standard of reference.

RESULTS

In assessing myometrial invasion, MR imaging showed 70% accuracy, 80% sensitivity, 40% specificity, 80% positive predictive value (PPV), and 40% negative predictive value (NPV). In detecting cervical invasion, MR imaging had 95% accuracy, 100% sensitivity, 94.4% specificity, 66.7% PPV, and 100% NPV. In evaluating lymph node involvement, MR imaging showed 100% accuracy, sensitivity, specificity, PPV and NPV. Errors in evaluating myometrial invasion were caused by polypoid tumour, adenomyosis and leiomyomas, whereas those in evaluating cervical invasion were caused by dilatation and curettage.

CONCLUSIONS

MR imaging is a reliable technique for preoperative evaluation of endometrial carcinoma. Its main limitation is differentiating between stage IA and IB carcinomas, which is not highly important for surgical planning. Cooperation between the gynaecologist and radiologist is mandatory to avoid staging errors.

Pelvic incidentalomas

Recent advances in multi-detector computed tomography, magnetic resonance imaging, and ultrasound have led to the detection of incidental ovarian, uterine, vascular and pelvic nodal abnormalities in both the oncology and non-oncology patient population that in the past remained undiscovered. These incidental pelvic lesions have created a management dilemma for both clinicians and radiologists. Depending on the clinical setting, these lesions may require no further evaluation, additional immediate or serial follow-up imaging, or surgical intervention. In this review, guidelines concerning the diagnosis and management of some of the more common pelvic incidentalomas are presented.

Multi-detector CT features of benign adnexal lesions

RATIONALE AND OBJECTIVES

The purpose of our study was to evaluate the multidetector computed tomography (MDCT) features of benign adnexal lesions.

METHODS AND MATERIALS

We report the MDCT features of 68 histologically proven benign adnexal lesions. Pathologic diagnoses were nonneoplastic adnexal cysts (n = 16), endometriomas (n = 12), serous or mucinous cystadenomas (n = 15), fibromas or fibrothecomas (n = 7), teratomas (n = 6), and a variety of benign adnexal lesions (n = 12). The CT protocol included scanning of the abdomen after the intravenous administration of iodinated contrast material (portal phase) using a detector collimation of 16 x 0.75 mm and a pitch of 1.2.

RESULTS

Ovarian cysts had a characteristic CT appearance of a cystic lesion, with smooth, thin wall, and occasionally a few septa. Serous and mucinous cystadenomas were detected as multilocular cystic tumors containing serous fluid or liquids of higher than water CT density, respectively. Dilated fallopian tube was seen as an oblong, tubular, fluid-filled structure. MDCT was accurate to characterize mature cystic teratomas. Endometriomas had a variable CT appearance, including a unilocular or multilocular cystic mass, and a homogeneous hyperdense mass lesion. Fibrous tissue had a 50 HU CT density in patients with fibromas or fibrothecomas.

CONCLUSION

MDCT may provide accurate diagnostic information about the benign nature of adnexal lesions.

Uterine fibroid embolization imaging: interventionalist's perspective

Uterine fibroid embolization (UFE) is a minimally invasive and well-accepted form of treatment for patients with symptoms from fibroids. Imaging is routinely performed before the procedure for various reasons and after the procedure in cases with either complications or incomplete response to UFE. The interventionalists performing the procedure require specific information from these imaging studies. This article describes the imaging workup of patients referred for UFE, specifically the information from these imaging examinations before the procedure that are necessary to the interventionalist and the complications seen after the procedure.

Sonography of the pelvis in patients with primary amenorrhea

Duplex/color Doppler sonography (US) is the imaging modality of choice for the evaluation of patients with primary amenorrhea. Careful correlation with clinical history, physical examination and laboratory findings significantly narrows the diagnostic possibilities thus allowing for a more precise diagnosis. This article discusses the wide gamut of etiologies of primary amenorrhea, the US appearance of pathologic processes that result in primary amenorrhea, and helps the reader understand when additional higher tech imaging is indicated.

Diameter-by-age reference curves for the uterine cervix by computerized tomography

OBJECTIVE

To create diameter-by-age reference curves for the uterine cervix using computerized tomographic studies.

METHODS

Measurements of the anterior-posterior (AP) and lateral diameters of nonpathological cervices were made at the level of the vaginal fornices in 499 computerized tomographic studies. Patients were grouped by 10-year age intervals. For each age group, median AP and lateral cervical diameters were calculated, as were 10th and 90th percentile values. Values for the 3 curves were smoothed across age categories using second-order polynomial regression procedures.

RESULTS

The median AP diameter was 26 mm (range, 15-45 mm), and the median lateral diameter was 32 mm (range, 20-70 mm). For both measurements, the range of values between the 10th and 90th percentiles decreased with increasing age, creating funnel-shaped plots.

CONCLUSIONS

Radiological measurements of cervical diameters and comparison to standard curves may contribute information in the evaluation of uterine cervical pathology or may heighten awareness of pathologies not previously identified.

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.

Preoperative investigations in the management of peritoneal surface malignancy with cytoreductive surgery and perioperative intraperitoneal chemotherapy: Expert consensus statement

At the Fifth International Workshop on Peritoneal Surface Malignancy, in Milan, the consensus on preoperative investigations for peritoneal surface malignancy was obtained through the Delphi process. The results showed that 100% of the voters considered that contrast-enhanced multi-sliced CT was the fundamental imaging modality, whereas MRI, PET, laparoscopy and serum tumor markers were regarded as useful, but not fundamental investigational modalities.

Verwendung der Magnetresonanztomographie in der Diagnostik von Neoplasien der Vulva und Vagina

Magnetic resonance imaging (MRI) is widely accepted as an established method in the diagnostic imaging of diseases of the female pelvis. This review article describes the role of MRI in the diagnosis of neoplasms of the vulva and the vagina. MRI is useful in the pretherapeutic staging of vulval and vaginal neoplasms in order to assess tumor size, local tumor extent and presence of lymph node metastases. Further indications for MRI are the diagnosis of posttherapeutic changes and tumor recurrence.

Magnetic resonance imaging of adnexal masses

Adnexal masses are common in women of all ages. A range of physiological and benign ovarian conditions that develop in women, especially in the reproductive age, and adnexal malignancies can be evaluated with magnetic resonance imaging (MRI). Management of women with adnexal masses is frequently guided by imaging findings; therefore, precise characterization of adnexal pathology should be performed whenever possible. Magnetic resonance imaging is useful in characterization of adnexal masses that are not completely evaluated by ultrasound because it can provide additional information on soft tissue composition of adnexal masses based on specific tissue relaxation times and allows multiplanar imaging at large field of view to define the origin and extent of pelvic pathology. The patients most likely to benefit from MRI are pregnant women and those who are premenopausal and have masses that have complex features on ultrasound but do not have raised cancer antigen 125 tumor marker levels. The overlap in imaging appearance among different cell type malignancies makes it difficult to predict exact histology based on MRI appearance; however, MRI has a high accuracy in differentiating benign from malignant masses. Teratomas, endometriomas, simple and hemorrhagic cysts, fibromas, exophytic or extrauterine fibroids, and hydrosalpinges can be diagnosed with high confidence. In this article, the authors review the histopathologic background and MRI features of adnexal masses and discuss the role of MRI in the differentiation of benign from malignant adnexal pathologies.

MR Imaging of Benign Uterine Disease

MR provides excellent depiction of the female pelvic anatomy and has become the imaging modality of choice for the accurate diagnosis of numerous benign gynecologic conditions. Detection and characterization of leiomyomata and adenomyosis is performed routinely at many centers, and MR plays an important role in stratifying patients into appropriate treatment options. MR imaging is also uniquely well suited to the evaluation of gynecologic conditions that occur during pregnancy and in the postpartum period. This article describes MR protocols and the typical findings of various benign conditions of the uterine corpus and cervix, including congenital anomalies, leiomyomas, adenomyosis, and complications related to pregnancy.

MR Imaging of Malignant Uterine Disease

The role of MR imaging in the diagnosis and management of patients who have uterine malignancy continues to evolve. MR imaging has been shown to be effective for preoperative characterization and staging of endometrial and cervical carcinoma, and for the evaluation of posttreatment changes and recurrent disease. Because of its potential to provide detailed information about local extent and metastatic disease, MR imaging has enormous potential to help triage patients to appropriate treatment groups and provide imaging surveillance after therapy. This article reviews the MR imaging technique and the imaging characteristics of malignant disease of the uterine corpus and cervix.

Multidetector CT of the Female Pelvis

In the emergency room setting, multidetector detector CT (MDCT) offers rapid, noninvasive, multiplanar evaluation of female patients who have acute pelvic pain. MDCT has been integrated into several of the major trauma centers, and its use may surpass the use of ultrasound in the trauma evaluation of the pregnant patient. In the nonemergent setting, MDCT can be used to stage gynecologic malignancy and to evaluate tumor recurrence. Multiplanar MDCT has received some acceptance for evaluation of small primary tumor volume and small metastatic implants. MDCT also has a role in the evaluation of pelvic varices and suspected pelvic congestion syndrome.

The use of MRI in the diagnosis and management of a bulky cervical carcinoma

BACKGROUND

In the treatment of gynecologic cancer, surgical planning depends on the site and extent of disease. The evaluation of the origin of a large pelvic mass with combined pelvic examination and ultrasound is often adequate. However, the following case report illustrates the utility of magnetic resonance imaging (MRI) when sonographic findings are indeterminate and the origin of a pelvic mass is unclear.

CASE

A 73-year-old woman presented for her first gynecologic exam in over 40 years. On speculum examination the cervix was not visible. A large, mobile pelvic mass was palpated during physical examination. Pelvic ultrasound revealed a large, cystic pelvic mass thought to be ovarian in origin. Surgery for presumed ovarian carcinoma was planned. Because a vaginal Pap smear revealed squamous-cell carcinoma, MRI was performed for further evaluation. MRI demonstrated a blood distended uterus with a large cervical tumor obstructing the endocervical os. After cervical dilatation under sonographic guidance, evacuation of the hematometrium was performed. Multiple biopsies of the cervix confirmed the diagnosis of a bulky Stage IIA squamous-cell carcinoma of the cervix. The patient was subsequently treated with concomitant chemotherapy and radiation therapy. Follow-up MRI demonstrated an excellent treatment response. Modified radical hysterectomy was performed demonstrating very small residual tumor.

CONCLUSIONS

Magnetic resonance imaging, through multiplanar capabilities and high-contrast resolution, is a valuable tool that can assist the clinician in the evaluation, diagnosis, and management of challenging gynecologic malignancies.

Whole-body PET with FDG is useful for following up an ovarian cancer patient with only rising CA-125 levels within the normal range

In April 2000, a 54-year-old woman underwent surgery for ovarian serous cell carcinoma (stage IIb). After initial treatment, the patient underwent a physical examination, ultrasound examination and measurement of serum CA-125 levels every month. Although neither diagnostic imaging (ultrasound and computed tomography) nor physical examination showed any evidence of recurrence, the CA-125 level rose slowly and continuously within the normal range. In March 2001, an increased accumulation of 18F-fluorodeoxyglucose (FDG) in the pelvic cavity was seen on a positron emission tomography (PET) scan obtained 2 weeks before a relapse of a malignant lesion was diagnosed by gadolinium-enhanced MRI (Gd-MRI). It is reasonable to suppose that FDG-PET is clinically useful for detecting an early, small region of relapsed ovarian cancer. Moreover, FDG-PET may be helpful for determining whether a patient who has a continuous rising CA-125 level within the normal range should be treated in the absence of relapse regions detected by conventional methods.

Asymptomatic adnexal masses: correlation of FDG PET and histopathologic findings

PURPOSE

To analyze asymptomatic adnexal masses at positron emission tomography (PET) with fluorodeoxyglucose (FDG) in correlation with histopathologic findings and evaluate FDG PET for assessing malignancy in comparison with transvaginal B-mode and Doppler ultrasonography (US) and magnetic resonance (MR) imaging.

MATERIALS AND METHODS

Ninety-nine patients underwent static FDG PET of the abdomen. US scans were evaluated according to sonomorphologic scoring systems. Resistance index of tumor blood vessels was calculated. Transverse and sagittal T1-weighted MR images obtained before and after intravenous administration of gadopentetate dimeglumine with a fat-saturation technique and T2-weighted MR images were acquired at 1.5 T. Adnexal mass malignancy was first assessed with each modality and then with a combination of the three techniques. Final diagnosis was made with histopathologic evaluation.

RESULTS

FDG PET depicted seven of 12 malignant and 66 of 87 benign asymptomatic adnexal tumors. False-negative PET results were obtained in five of seven stage pT1a cystadenocarcinomas and tumors of low malignant potential but not in advanced-stage ovarian carcinomas. Small moderately intense FDG accumulations in the lower pelvis were caused by benign adnexal tumors or gastrointestinal activity in 21 of 27 cases. The overall sensitivities and specificities were 58% (95% CI: 27.7, 84.8) and 76% (95% CI: 65.5, 84.4), respectively, for FDG PET; 92% (95% CI: 61.5, 99.8) and 60% (95% CI: 48.7, 70.1), respectively, for US; 83% (95% CI: 51.6, 97.7) and 84% (95% CI: 74.5, 90.9), respectively, for MR imaging; and 92% (95% CI: 61.5, 99.8) and 85% (95% CI: 75.8, 91.8), respectively, for the combination of three modalities.

CONCLUSION

Since the sensitivity of US is as high as that of PET, MR imaging, and the combination of three modalities, it remains the method of choice for diagnosis and assessment of asymptomatic adnexal masses.

Detection and characterization of adnexal masses

The main challenge to the radiologist is to differentiate benign from malignant adnexal masses. Both US and MRI perform well for prediction of benignity. There is less specificity for diagnosis of malignancy but features, such as papillary projections, thickened septations, and internal vascularity within nodules, aid in this differentiation. The combination of morphology and Doppler characteristics provide the most accurate US diagnosis. For sonographically indeterminate masses, MRI is useful for additional lesion characterization. Analysis of T1- and T2-weighted signal intensities for benign-appearing lesions with the addition of fat saturation for high signal on T1-weighted sequences may lead to an exact diagnosis or a narrow differential. For cases considered suspicious by TVUS, more specific diagnosis by MRI may obviate the need for surgery or otherwise change management by identification of benign etiology.