Role Of Preoperative Magnetic Resonance Imaging Research Articles

The role of preoperative MRI in endoscopic transnasal transsphenoidal hypophysectomy of pituitary adenoma.

The trans-sphenoidal approach, commonly used for removing pituitary adenomas, has become a widely accepted and successful method. In recent years, the endoscopic trans-sphenoidal technique has emerged as a minimally invasive surgical approach for pituitary adenoma removal. The majority of pituitary adenomas exhibit a soft consistency and can be successfully extracted with aspiration and curettage using the trans-sphenoidal approach. However, a subset of around 5-15% of these adenomas possess a solid and fibrous texture. The occurrence of firm and fibrous adenomas is relatively common; unfortunately, there are no reliable predictors to identify them preoperatively. The ability to forecast the reliability of magnetic resonance imaging (MRI) holds promise for improving prior preparation and impacts the extent of resection. A cross-sectional analysis of the investigation of magnetic resonance imaging (MRI) in relation to cancer histology was performed on 68 patients who had endoscopic trans-nasal excision for nonfunctional adenomas. The determination of an intensity ratio was performed by employing quantitative estimates of MRI signal intensity obtained from both the adenoma and pons. During the surgical procedure, a series of sequential-graded procedures were used for the removal of tumours with varying consistencies. Softer tumours were addressed using the Suction technique (R1), while tumours of intermediate consistency were treated using curettes (R2). In order to evaluate the fibrotic content of firmer tumours, the utilization of Cavitron Ultrasound Surgical Aspirator(CUSA), and/or other micro-instruments (R3) was employed, with the histologic collagen fraction being quantified. In order to investigate and analyse the data, a statistical analysis was conducted. A predictive relationship between resection category and both intensity ratio, and collagen percentage was noted. The primary objective of this study was to determine the appropriate cutoff criteria for clinical utilization, as well as to investigate the association between intensity ratios and collagen percentage. Tumors with ratios ≤ 1.6 on the T2-weighted image and collagen content > 5.3% required more meticulous and sharp dissection for resection. The utilization of MRI analysis may offer some assistance, but not conclusive, in the prediction of tumour consistency.

Abstract OT2-02-01: Brazilian randomized study - Impact of preoperative magnetic resonance in the evaluation for breast cancer conservative surgery (BREAST-MRI trial)

Abstract Background: A precise preoperative evaluation of the tumor is essential to improve breast cancer surgical management. Currently, mammography associated with ultrasound and clinical exam are the standard techniques for evaluating extension and tumor localization. However, approximately one third of the lesions in patients eligible for conservative surgical treatment are misevaluated by these methods. Breast magnetic resonance imaging (MRI) has a high sensitivity (95-100%) in detecting invasive neoplasms, and is able to detect occult tumors, multifocal and/or multicentric disease, and contralateral breast cancer more accurately than mammography and ultrasound. Until now, there are only three randomized trials assessing the role of preoperative MRI. These trials have different designs and contradictory results. Trial design: BREAST-MRI is a randomized, open label, unblinded trial designed to compare the accuracy of breast MRI in the preoperative planning of surgical treatment of breast cancer to standard protocol (clinical exam of the breast, mammography and/or breast ultrasound) and the impact of breast MRI on breast cancer outcome. Patients are randomized on a 1:1 basis, stratified for mammary density, into two groups: 1)MRI group: patients are submitted to MRI and standard protocol 2)Control group: standard protocol. First phase: patient recruitment and data collection up until surgery. Second phase: follow-up for five years or until death. Eligibility criteria: women aged 18 years or older with breast cancer stages I to III candidates for conservative surgery (CC). Specific aims: The aim of this study is to evaluate the ability of MRI in selecting patients for conservative treatment of breast cancer. Primary outcomes are: false positive rates, false negative rates, positive predictive value and negative predictive value of MRI in breast cancer CC. Secondary outcomes are: rates of positive margins on pathological examination; reoperation rates; number of conversions to mastectomy; accuracy of MRI according to mammographic density, immunohistochemical subtype and histopathology of the tumor; rates of multicentricity, multifocality and bilateralality of tumors; disease-free survival after 3 and 5 years; and cost-effectiveness of breast MRI. Statistical methods: The calculated total case number for this trial is 372, assuming a recurrence rate of 10% for CC and 1% for mastectomies. The Shapiro-Whilks test will be used to verify if distribution of the quantitative variables follows normal distribution. The baseline population will be analyzed using the t-Student test, or the Mann-Whitney test when appropriate. To test the existence of a possible association between outcomes and the categorized characteristics, chi-square and Fisher's exact test will be performed. Disease progression will be reassessed at 3 and 5 years follow-up, in order to produce a log-rank Kaplan-Meier curve of survival. Present accrual and target accrual: In June 2017, randomizations are at approximately 90% of the target sample size. Citation Format: Dória MT, Mota BS, Reis YN, Ricci MD, Piato JRM, Ferreira VCCS, Shimizu C, Barros N, Filassi JR, Baracat EC. Brazilian randomized study - Impact of preoperative magnetic resonance in the evaluation for breast cancer conservative surgery (BREAST-MRI trial) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-02-01.

Stage IB1 Cervical Cancer: Role of Preoperative MR Imaging in Selection of Patients for Fertility-Sparing Radical Trachelectomy

To determine whether magnetic resonance (MR) imaging evaluation of key morphologic tumor characteristics can improve patient selection for radical trachelectomy. The institutional review board approved and waived informed consent for this study of 62 patients (mean age, 32 years; age range, 23-42 years) with International Federation of Gynecology and Obstetrics stage IB1 cervical carcinoma who underwent attempted radical trachelectomy between November 2001 and January 2011 and had preoperative MR imaging. Retrospectively, two radiologists reviewed MR images for tumor presence and size, distance between tumor and internal os, and presence of deep cervical stromal invasion. Associations between MR imaging findings and surgery type were tested. Sensitivity and specificity of tumor detection were, respectively, 87% and 100% (reader 1) and 76% and 95% (reader 2). Six of six patients with negative cone biopsy margins and no tumor at postconization MR imaging were without tumor at trachelectomy pathologic analysis. Mean differences between MR imaging and histologic tumor sizes were 0.7 mm (range, -15 to 11 mm) for reader 1 and 2.2 mm (range, -9 to 15 mm) for reader 2. Sensitivities for deep cervical stromal invasion were 75% (reader 1) and 50% (reader 2). For each reader, nine of nine (100%) patients with tumor 5 mm or less from the internal os and three of five (60%) patients with tumor 6-9 mm from the internal os at MR imaging needed radical hysterectomy. For both readers, tumor size of 2 cm or larger (P < .001) and deep cervical stromal invasion (P ≤ .003) at MR imaging were associated with increased chance of radical hysterectomy. Pretrachelectomy MR imaging can help identify high-risk patients likely to need radical hysterectomy or confirm the absence of residual tumor in the cervix after a cone biopsy with negative margins.

Review of Preoperative Magnetic Resonance Imaging (MRI) in Breast Cancer: Should MRI Be Performed on All Women with Newly Diagnosed, Early Stage Breast Cancer?

Randomized controlled trials have shown equivalent survival for women with early stage breast cancer who are treated with breast-conservation therapy (local excision and radiotherapy) or mastectomy. Decades of experience have demonstrated that breast-conservation therapy provides excellent local control based on defined standards of care. Magnetic resonance imaging (MRI) has been introduced in preoperative staging of the affected breast in women with newly diagnosed breast cancer because it detects additional foci of cancer that are occult on conventional imaging. The median incremental (additional) detection for MRI has been estimated as 16% in meta-analysis. In the absence of consensus on the role of preoperative MRI, we review data on its detection capability and its impact on treatment. We outline that the assumptions behind the adoption of MRI, namely that it will improve surgical planning and will lead to a reduction in re-excision surgery and in local recurrences, have not been substantiated by trials. Evidence consistently shows that MRI changes surgical management, usually from breast conservation to more radical surgery; however, there is no evidence that it improves surgical care or prognosis. Emerging data indicate that MRI does not reduce re-excision rates and that it causes false positives in terms of detection and unnecessary surgery; overall there is little high-quality evidence at present to support the routine use of preoperative MRI. Randomized controlled trials are needed to establish the clinical, psychosocial, and long-term effects of MRI and to show a related change in treatment from standard care in women newly affected by breast cancer.

The utility of preoperative breast magnetic resonance imaging in invasive breast cancer according to HER2 status.

Abstract Abstract #4020 Background: HER2 positive (HER2+) breast cancer accounts for 20% of all breast cancer and is an independent adverse prognostic factor. Breast magnetic resonance imaging (MRI) has been shown to identify additional mammographically occult ipsilateral (I/L) and contralateral (C/L) disease, however indications for preoperative MRI in patients with newly diagnosed breast cancer are not standardized. While invasive lobular cancer, younger patient age, and increased breast density have been suggested as routine indications, the role of preoperative MRI according to HER2 status has not been evaluated.&amp;#x2028; Methods: All patients with invasive breast cancer who underwent preoperative MRI between January 2003 and December 2007 were reviewed. Retrospective chart review was performed to collect clinical, radiographic, and pathologic data. The incidence of additional I/L or C/L malignacy was calculated. Additionally, changes in surgical management because of MRI findings were recorded.&amp;#x2028; Results: Of the 401 women with invasive breast cancer undergoing preoperative breast MRI, 51 (13%) had HER2+ tumors. The average age at the time of MRI was similar in both groups. HER2+ patients were more likely to have nodal disease, and tumors with higher rates of lymphovascular invasion or extensive intraductal components.&amp;#x2028; &amp;#x2028; When compared to HER2- patients, more HER2+ patients had additional ipsilateral MRI abnormalities. A second ipsilateral cancer was found in 31% of HER2+ patients compared to 25% of HER2- patients. When analyzed according to ER status, HER2+/ ER- patients were more likely to have an additional site of cancer compared to HER2+/ER+ patients (42% vs 23%). Conversely, among HER2- patients, rates of additional ipsilateral cancer were similar for HER2-/ER+ (26%) and HERr2-/ER- (23%) patients. Of the 216 patients (HER2+ and HER2-) with additional ipsilateral MRI findings (benign or malignant), 125/216 (58%) patients were deemed appropriate breast conservation (BCT) candidates after MRI. However, BCT was only chosen in 84/125 (67%) patients. Additional contralateral disease was documented in 8% of HER2+ versus 5% of HER2- patients.&amp;#x2028; Conclusions: HER2 positivity remains and important prognostic factor for women with breast cancer. Indications for routine preoperative MRI are unclear. In patients with newly diagnosed Her2+ invasive breast cancer routine preoperative MRI may be valuable in the subset of patients who are also ER-. Further study is needed to determine the influence of MRI on patient decisions for surgical therapy. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4020.

The ability of preoperative magnetic resonance imaging to predict actual pathologic tumor size in women with newly diagnosed breast cancer.

Abstract Abstract #4018 Background: Preoperative breast magnetic resonance imaging (MRI) has been shown to identify occult breast disease in women with newly diagnosed breast cancer. We sought to determine the accuracy of MRI in predicting the actual pathologic tumor size in women with newly diagnosed breast cancer.&amp;#x2028; Methods: Preoperative breast MRI was reviewed in 460 women with newly diagnosed breast cancer. The size in terms of maximum tumor dimension, of 476 incident breast cancers on MRI were recorded and correlated with the actual pathologic size upon surgical resection. The correlation of size from MRI to pathology was determined. The size discrepancy was analyzed in relation to tumor size and histology.&amp;#x2028; Results: MRI demonstrated 476 breast cancers (460 in the ipsilateral breast and 16 with concurrent contralateral breast cancer). Median age was 62 with a range of 25 to 91. The T stages of the population included T0 in 19% of the women, 60% had T1 lesions, 18% had T2 lesions and 3% were T3 or T4. The histology consisted of DCIS alone in 20%, infiltrating ductal in 74% and infiltrating lobular in 6%. Pre-operative MRI was unable to define an enhancing lesion usually due to hematoma following core needle biopsy in 9.8% (47/476). MRI described the size of the incident lesion in 90% (429/476). The mean difference in size between the preoperative MRI and the actual pathologic size for the entire group was 2.4 mm. MRI underestimated tumor size in only 3% of cases. The mean difference according to T stage and histology between MRI and actual pathologic size is listed in Table 1. The percentage of difference between MRI size and pathologic size for the entire group is presented in Table 2.&amp;#x2028; &amp;#x2028; &amp;#x2028; &amp;#x2028; Discussion: The mean difference in tumor size estimated by preoperative MRI in women with newly diagnosed breast cancer was within 5 mm of the actual pathologic size in 68% of patients. MRI was accurate in predicting T stage with no significant difference in relation to histology or T stage. This analysis further clarifies the role of preoperative MRI in surgical and treatment planning. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4018.