Magnetic Resonance Imaging Tumor Size Research Articles

Diagnostic accuracy of pre-operative breast magnetic resonance imaging (MRI) in predicting axillary lymph node metastasis: variations in intrinsic subtypes, and strategy to improve negative predictive value—an analysis of 2473 invasive breast cancer patients

BackgroundThe value and utility of axillary lymph node (ALN) evaluation with MRI in breast cancer were not clear for various intrinsic subtypes. The aim of the current study is to test the potential of combining breast MRI and clinicopathologic factors to identify low-risk groups of ALN metastasis and improve diagnostic performance.Material and methodsPatients with primary operable invasive breast cancer with pre-operative breast MRI and post-operative pathologic reports were retrospectively collected from January 2009 to December 2021 in a single institute. The concordance of MRI and pathology of ALN status were determined, and also analyzed in different intrinsic subtypes. A stepwise strategy was designed to improve MRI-negative predictive value (NPV) on ALN metastasis.Results2473 patients were enrolled. The diagnostic performance of MRI in detecting metastatic ALN was significantly different between intrinsic subtypes (p = 0.007). Multivariate analysis identified tumor size and histologic type as independent predictive factors of ALN metastases. Patients with HER-2 (MRI tumor size ≤ 2 cm), or TNBC (MRI tumor size ≤ 2 cm) were found to have MRI–ALN-NPV higher than 90%, and these false cases were limited to low axillary tumor burden.ConclusionThe diagnostic performance of MRI to predict ALN metastasis varied according to the intrinsic subtype. Combined pre-operative clinicopathologic factors and intrinsic subtypes may increase ALN MRI NPV, and further identify some groups of patients with low risks of ALN metastasis, high NPV, and low burdens of axillary disease even in false-negative cases.

Revisit the practice of lymph node biopsy in patients diagnosed as ductal carcinoma in situ before operation: a retrospective analysis of 682 cases and evaluation of the role of breast MRI

BackgroundThe optimal axillary lymph node (ALN) management strategy in patients diagnosed with ductal carcinoma in situ (DCIS) preoperatively remains controversial. The value of breast magnetic resonance imaging (MRI) to predict ALN metastasis pre-operative DCIS patients was evaluated.MethodsPatients with primary DCIS with or without pre-operative breast MRI evaluation and underwent breast surgery were recruited from single institution. The value of breast MRI for ALN evaluation, predictors of breast and ALN surgeries, upgrade from DCIS to invasive cancer, and ALN metastasis were analyzed.ResultsA total of 682 cases with pre-operative diagnosis of DCIS were enrolled in current study. The rate of upgrade to invasive cancer were found in 34.2% of specimen, and this upgrade rate is 23% for patients who received breast conserving surgery and 40.7% for mastectomy (p < 0.01). Large pre-operative imaging tumor size and post-operative invasive component were risk factors to ALN metastasis. Breast MRI had 53.8% sensitivity, 77.8% specificity, 14.9% positive predictive value, 95.9% negative predictive value (NPV), and 76.2% accuracy to predict ALN metastasis in pre-OP DCIS patients. In MRI node-negative breast cancer patients with MRI tumor size < 3 cm, the NPV was 96.4%, and all these false-negative cases were N1. Pre-OP diagnosed DCIS patients with MRI tumor size < 3 cm and node negative suitable for BCS could safely omit SLNB if whole breast radiotherapy is to be performed.ConclusionBreast MRI had high NPV to predict ALN metastasis in pre-OP DCIS patients, which is useful and could be provided as shared decision-making reference.

Direct comparison of magnetic resonance imaging and pathological shrinkage patterns of triple-negative breast cancer after neoadjuvant chemotherapy

BackgroundWe aimed to investigate the usefulness of magnetic resonance imaging (MRI) and histopathological shrinkage patterns to formulate a predictive equation for estimating residual tumor size after neoadjuvant chemotherapy (NAC) in triple-negative breast cancer (TNBC) patients.MethodsWe enrolled 34 TNBC patients who underwent MRI before and after NAC. The MRI and histopathological shrinkage patterns were analyzed and classified into five categories—types I and II (concentric shrinkage without or with surrounding lesions, respectively), type III (shrinkage with residual multinodular lesions), type IV (diffuse contrast enhancement in the entire quadrant), and non-visualization. The residual tumor sizes following MRI and histopathological examination were also compared.ResultsThe most common MRI and histopathological shrinkage pattern was type I (41.2% and 38.2%, respectively), followed by non-visualization (26.5% and 32.4%, respectively); the concordance rate between MRI and histopathological shrinkage patterns was 41.2%. There was a strong correlation between MRI tumor size and pathological tumor size (r = 0.89). Based on these findings, a predictive equation for pathological tumor size was formulated as follows: pathological tumor size (mm) = 1.1502 × (MRI tumor size [mm]) + 8.4277.ConclusionsOur equation may aid accurate preoperative assessment. Further studies are needed to determine its predictive value and applicability.

Outcomes of pre-operative brachytherapy followed by hysterectomy for early cervical cancer

ObjectiveThe standard of care for early cervical cancer is radical hysterectomy; however, consideration of pre-operative brachytherapy has been explored. We report our experience using pre-operative brachytherapy plus Wertheim-type hysterectomy to...

Preoperative Staging in Women with Known Breast Cancer: Comparison between Digital Breast Tomosynthesis (DBT) and Magnetic Resonance Imaging (MRI)

Objectives&#x0D; &#x0D; To prospectively evaluate the accuracy in tumor extent and size assessment of Digital Breast Tomosynthesis (DBT) and Magnetic Resonance Imaging (MRI) in women with known breast cancer, with pathological size as the gold standard.&#x0D; &#x0D; Methods&#x0D; &#x0D; From May 2014 to April 2016, 50 patients with known breast cancer were enrolled in our prospective study. All patients underwent MRI on a 3T magnet and DBT projections. Two radiologists, with 15 and 7 years of experience in breast imaging respectively, evaluated in consensus each imaging set unaware of the final histological examination. MR and DBT sensitivity, PPV and accuracy were calculated, using histology as the gold standard. McNemar test was used to compare MR and DBT sensitivity. Correlation and regression analyses were used to evaluate MRI vs Histology, DBT vs Histology and MRI vs DBT lesions tumor size agreement to histological results. &#x0D; &#x0D; Results&#x0D; &#x0D; On histological examination 70 lesions were detected. MRI showed 100% sensitivity, 96% PPV and 96% accuracy; DBT sensitivity was 81%, PPV 92% and accuracy 77%. McNemar test p-value was 0.0003. Lesions size Pearson correlation coefficient was 0.97 for MRI vs Histology, 0.92 for DBT vs Histology, (p-value&amp;lt;0.0001). MRI vs DBT regression coefficient was 0.83.&#x0D; &#x0D; Conclusions&#x0D; &#x0D; MRI confirmed to be the most accurate imaging technique in preoperative staging of breast cancer. However, DBT showed very good accuracy, sensitivity and tumor size assessment and could be a valid tool for preoperative staging when MRI is contraindicated.

Predicting the necessity of adding catheters to intracavitary brachytherapy for women undergoing definitive chemoradiation for locally advanced cervical cancer

PurposeTo identify if baseline patient or magnetic resonance imaging (MRI) features can predict which women are at risk for inadequate tumor coverage with only intracavitary tandem and ovoid (T + O) brachytherapy and to correlate tumor coverage with clinical outcomes. Methods and MaterialsWe performed a retrospective study of 50 women with cervical cancer treated with chemoradiation at a single institution between January 2014 and December 2015. All patients had a 3T-MRI performed at baseline (MRI1) and at the completion of external beam radiation therapy (MRI2). Gross tumor volume initial (GTV-Tinit) was measured on MRI1 and high-risk clinical tissue volume (CTVHR) on MRI2. CTVHR extending beyond point A was classified as too large for adequate coverage with T + O and requiring interstitial needles. Multivariate analysis was performed to determine predictive factors of inadequate coverage. Kaplan–Meier and Cox Regression were performed to correlate inadequate coverage with outcomes. ResultsMean patient age was 49.2 ± 13.2 years, and 84% had Federation of Gynecology and Obstetrics IIB/IIIB disease. Forty-two percent of women were estimated to have inadequate tumor coverage with T + O brachytherapy. The GTV-Tinit volume and dimensions (superior-inferior, left-right, anterior-posterior) on MRI1 were all important predictive factors of inadequate coverage on multivariate analysis. Receiver operating characteristics curves identified optimal thresholds of superior-inferior ≥ 4.5 cm (area under the curve [AUC] = 0.718), left-right ≥ 4.5 cm (AUC = 0.745), anterior-posterior ≥ 5.0 cm (AUC = 0.767), and GTV-Tinit ≥ 85 cm3 (AUC = 0.842). Patients with inadequate coverage had worse clinical outcomes. ConclusionsBaseline MRI tumor size may predict inadequate CTVHR coverage at the time of brachytherapy (i.e., the need for interstitial needles). This may help identify a subset of women requiring early referral to adequately resourced centers to improve clinical outcomes.

Abstract P5-22-02: Surgical strategy after neoadjuvant therapy in patients with operable breast cancer can be optimized by knowledge of the level of agreement of measured tumor size on MRI after neoadjuvant therapy and final pathologic assessment

Abstract Introduction Neoadjuvant chemotherapy (NAC) is increasingly applied in the treatment of patients with operable breast cancer. Wide local excision after NAC aims to remove the complete residual tumor with no tumor on ink, without compromising cosmetics. Therefore, surgical strategies are determined based on the remaining tumor size after NAC visualized on magnetic resonance imaging (MRI). Recent studies on the correlation between preoperative MRI and pathological response demonstrate inconsistent results. A need remains to adequately guide surgical decisions after NAC. The aim of this study was to not only investigate the correlation between MRI and pathological evaluation but to gain knowledge of the exact level of agreement, specified for different tumor subtypes, which could further guide surgical decision making. Methods All patients operated for breast cancer after NAC between January 2013 and July 2016 in a large teaching hospital were retrospectively included. Longest residual tumor diameter was determined with MRI and correlated with postoperative pathological findings. Tumors were subdivided based on estrogen receptor (ER) status and human epidermal growth factor receptor 2 (HER2). Spearman correlation was used to correlate MRI and pathological tumor size findings. Bland-Altman method was used to evaluate the agreement between both measurements. Results 193 patients with 195 breast cancers were included. The correlation between tumor size at MRI and pathology was 0.63 for the whole group, 0.39 for tumors with subtype ER+/HER2-, 0.55 for ER+/HER2+, 0.63 for ER-/HER2+ and 0.85 for ER-/HER2-. The correlation for lobular carcinomas was 0.44. The mean difference and limits of agreement (LoA), between tumor size measured at MRI and pathological size was 4.6 mm (LoA -27.0 to 36.3 mm, n=195). Mean difference and LoA for subtype ER+/HER2- was 7.6 mm (LoA -31.3 to 46.5 mm, n=100), for ER+/HER2+ 0.9 mm (LoA -8.5 mm to 10.2 mm, n=33), for ER-/HER2+ -1.2 mm (LoA -5.1 to 7.5 mm, n=21), for ER-/HER- -0.4 mm (LoA -8.6 to 7.7 mm, n=41) and 19.4 mm (LoA -16.8 to 55.6 mm, n=14) for lobular carcinoma. Conclusion The correlation and agreement between the post-NAC MRI and postoperative pathological assessment of residual tumor size for ER+/Her2- and lobular tumors is weak. The agreement shows a wide variation in over- and underestimation of tumor size in mm by MRI and thus surgical strategy can still be poorly guided. It does however provide us with exact information on the possible range of margins we should take into account at surgery. As demonstrated in other studies ER+/HER2+, ER-/HER2+ and ER-/HER2- tumors demonstrate a clear correlation. Also, the level of agreement in these tumor subtypes shows that we can use MRI evaluation as a reliable predictive tool of tumor residual size to base our surgical strategy upon with a small variation in over- and underestimation of tumor size. Because the lobular carcinoma and HER2+ subgroups were small, conclusions should of course be viewed cautiously. Citation Format: Boersma C, van Veen JLC, Maaskant JM, Van der Starre-Gaal J, Van 't Veer-Ten Kate M, Francken AB, Noorda EM. Surgical strategy after neoadjuvant therapy in patients with operable breast cancer can be optimized by knowledge of the level of agreement of measured tumor size on MRI after neoadjuvant therapy and final pathologic assessment [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 P5-22-02.

Tumor size assessment of invasive breast cancers: which pathological features affect MRI-pathology agreement?

BackgroundPreoperative assessment of tumor size is important in breast cancer treatment planning, especially in breast conservation surgeries. The use of the Magnetic Resonance Imaging (MRI) is increasing among patients with newly diagnosed breast cancers. However, some pathological features can overestimate the measurement of tumor size by MRI, increasing mastectomy rates. The objective is to evaluate which pathological features may affect the agreement between MRI and pathologic tumor size on invasive breast carcinomas.MethodsEighty seven patients with breast cancer who underwent preoperative breast MRI were retrospectively evaluated. The main tumor size measured by MRI was compared with pathology (gold standard) and concordance was defined as a greater diameter difference of less than 10 mm.ResultsThere was MRI-pathology concordance in 60 cases (69.0%), MRI overestimated tumor size in 21 (24.1%) and underestimated in 6 (6.9%). After multivariate analysis, only associated ductal carcinoma in situ (DCIS) remained significantly related to overestimation of tumor size on MRI (OR: 9.00; 95% IC:1.13-71.87; p = 0.038).ConclusionThere was good correlation between tumor size evaluation on MRI and pathology. The presence of associated DCIS was the only pathological parameter associated with size overestimation on MRI.

Agreement between MRI and pathologic analyses for determination of tumor size and correlation with immunohistochemical factors of invasive breast carcinoma.

Background There may be discordance between tumor size determined by magnetic resonance imaging (MRI) and that observed during pathologic analyses. Purpose To evaluate MRI-pathology concordance of tumor size in patients with invasive breast carcinoma. Material and Methods Data from 307 invasive breast carcinomas were analyzed retrospectively. Preoperative breast MRI was reviewed for size, lesion type, morphology, and dynamic contrast-enhanced tumor kinetics. MRI tumor size was compared with tumor size measurements from the pathologic analysis. Concordance was defined as a difference in diameter of ≤ 0.5 cm. MRI-pathology concordance was compared according to clinical and histopathologic features. Results The mean tumor size on MRI was 2.48 ± 1.41 cm. Tumor measurements determined by MRI were not significantly different from those recorded in the pathologic reports (2.56 ± 1.61 cm, P = 0.199). MRI-pathology concordance was found in 229/307 (74.6%) cases; the size was overestimated in 36 (11.7%) tumors and underestimated in 42 (13.7%). On univariate analysis, MRI-pathology discordance was associated with larger tumor size ( P < 0.001), estrogen receptor (ER) negativity ( P = 0.006), and lymphovascular invasion ( P = 0.003). Human epidermal growth factor receptor 2 positive molecular subtype showed worse correlation between the tumor size measured by MRI and pathology compared with luminal A and luminal B subtypes ( P = 0.008 and 0.007). On multivariate analysis, tumor size and ER status significantly influenced MRI-pathology concordance ( P < 0.05). Conclusion ER negativity and larger tumor size were strongly associated with MRI-pathology discordance in invasive breast carcinomas. Awareness of these factors might improve surgical planning.

Evaluation of Soft Tissue Sarcoma Response to Preoperative Chemoradiotherapy Using Dynamic Contrast-Enhanced Magnetic Resonance Imaging.

This study aims to assess the utility of quantitative dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters in comparison with imaging tumor size for early prediction and evaluation of soft tissue sarcoma response to preoperative chemoradiotherapy. In total, 20 patients with intermediate- to high-grade soft tissue sarcomas received either a phase I trial regimen of sorafenib + chemoradiotherapy (n = 8) or chemoradiotherapy only (n = 12), and underwent DCE-MRI at baseline, after 2 weeks of treatment with sorafenib or after the first chemotherapy cycle, and after therapy completion. MRI tumor size in the longest diameter (LD) was measured according to the RECIST (Response Evaluation Criteria In Solid Tumors) guidelines. Pharmacokinetic analyses of DCE-MRI data were performed using the Shutter-Speed model. After only 2 weeks of treatment with sorafenib or after 1 chemotherapy cycle, Ktrans (rate constant for plasma/interstitium contrast agent transfer) and its percent change were good early predictors of optimal versus suboptimal pathological response with univariate logistic regression C statistics values of 0.90 and 0.80, respectively, whereas RECIST LD percent change was only a fair predictor (C = 0.72). Post-therapy Ktrans, ve (extravascular and extracellular volume fraction), and kep (intravasation rate constant), not RECIST LD, were excellent (C > 0.90) markers of therapy response. Several DCE-MRI parameters before, during, and after therapy showed significant (P < .05) correlations with percent necrosis of resected tumor specimens. In conclusion, absolute values and percent changes of quantitative DCE-MRI parameters provide better early prediction and evaluation of the pathological response of soft tissue sarcoma to preoperative chemoradiotherapy than the conventional measurement of imaging tumor size change.

Early Prediction and Evaluation of Breast Cancer Response to Neoadjuvant Chemotherapy Using Quantitative DCE-MRI

The purpose is to compare quantitative dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) metrics with imaging tumor size for early prediction of breast cancer response to neoadjuvant chemotherapy (NACT) and evaluation of residual cancer burden (RCB). Twenty-eight patients with 29 primary breast tumors underwent DCE-MRI exams before, after one cycle of, at midpoint of, and after NACT. MRI tumor size in the longest diameter (LD) was measured according to the RECIST (Response Evaluation Criteria In Solid Tumors) guidelines. Pharmacokinetic analyses of DCE-MRI data were performed with the standard Tofts and Shutter-Speed models (TM and SSM). After one NACT cycle the percent changes of DCE-MRI parameters Ktrans (contrast agent plasma/interstitium transfer rate constant), ve (extravascular and extracellular volume fraction), kep (intravasation rate constant), and SSM-unique τi (mean intracellular water lifetime) are good to excellent early predictors of pathologic complete response (pCR) vs. non-pCR, with univariate logistic regression C statistics value in the range of 0.804 to 0.967. ve values after one cycle and at NACT midpoint are also good predictors of response, with C ranging 0.845 to 0.897. However, RECIST LD changes are poor predictors with C = 0.609 and 0.673, respectively. Post-NACT Ktrans, τi, and RECIST LD show statistically significant (P < .05) correlations with RCB. The performances of TM and SSM analyses for early prediction of response and RCB evaluation are comparable. In conclusion, quantitative DCE-MRI parameters are superior to imaging tumor size for early prediction of therapy response. Both TM and SSM analyses are effective for therapy response evaluation. However, the τi parameter derived only with SSM analysis allows the unique opportunity to potentially quantify therapy-induced changes in tumor energetic metabolism.

Agreement between MRI and pathologic breast tumor size after neoadjuvant chemotherapy, and comparison with alternative tests: individual patient data meta-analysis.

BackgroundMagnetic resonance imaging (MRI) may guide breast cancer surgery by measuring residual tumor size post-neoadjuvant chemotherapy (NAC). Accurate measurement may avoid overly radical surgery or reduce the need for repeat surgery. This individual patient data (IPD) meta-analysis examines MRI’s agreement with pathology in measuring the longest tumor diameter and compares MRI with alternative tests.MethodsA systematic review of MEDLINE, EMBASE, PREMEDLINE, Database of s of Reviews of Effects, Heath Technology Assessment, and Cochrane databases identified eligible studies. Primary study authors supplied IPD in a template format constructed a priori. Mean differences (MDs) between tests and pathology (i.e. systematic bias) were calculated and pooled by the inverse variance method; limits of agreement (LOA) were estimated. Test measurements of 0.0 cm in the presence of pathologic residual tumor, and measurements >0.0 cm despite pathologic complete response (pCR) were described for MRI and alternative tests.ResultsEight studies contributed IPD (N = 300). The pooled MD for MRI was 0.0 cm (LOA: +/−3.8 cm). Ultrasound underestimated pathologic size (MD: −0.3 cm) relative to MRI (MD: 0.1 cm), with comparable LOA. MDs were similar for MRI (0.1 cm) and mammography (0.0 cm), with wider LOA for mammography. Clinical examination underestimated size (MD: −0.8 cm) relative to MRI (MD: 0.0 cm), with wider LOA. Tumors “missed” by MRI typically measured 2.0 cm or less at pathology; tumors >2.0 cm were more commonly “missed” by clinical examination (9.3 %). MRI measurements >5.0 cm occurred in 5.3 % of patients with pCR, but were more frequent for mammography (46.2 %).ConclusionsThere was no systematic bias in MRI tumor measurement, but LOA are large enough to be clinically important. MRI’s performance was generally superior to ultrasound, mammography, and clinical examination, and it may be considered the most appropriate test in this setting. Test combinations should be explored in future studies.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-015-1664-4) contains supplementary material, which is available to authorized users.

■ Dr. Constantin Cope Medical Student Research Award Transcatheter intraarterial delivery of superparamagnetic iron oxide-labeled natural killer lymphocytes to hepatocellular carcinoma: longitudinal efficacy studies in a rat model

Purpose Adoptive immunotherapy (AIT) with natural killer (NK) lymphocytes is a promising therapy for hepatocellular carcinoma (HCC). The purpose of this study was to test the hypotheses that superparamagnetic iron oxide (SPIO) nanoparticle labeling permits magnetic resonance imaging (MRI)-based quantification of NK delivery to HCC post infusion; intraarterial (IA) NK infusion demonstrates a therapeutic benefit compared to intravenous (IV) NK infusion; and NK delivery is correlated with tumor therapeutic response 8 days post infusion. Materials and Methods NK-92MIs were labeled with fluorescent SPIOs (GENOVIS, Sweden). 18 Sprague Dawley rats were implanted with McA-RH7777 tumors; 6 rats each comprised IA NK, IA saline, and IV NK groups. Catheter (Terumo Medical, NJ) was placed in hepatic artery or tail vein for IA NK/saline and IV NK infusions, respectively. MRI tumor size and T2* measurements were compared pre and 8 days post infusion. Tumor size changes, ΔT2*, and histological measurements were compared; Prussian blue staining was used for histological identification of labeled NK cells. CD56 and fluorescence microscopy qualitatively confirmed NK delivery. ANOVA, t-test, and Pearson correlation coefficients were used for statistical analyses. Results 91.7%, 85.7%, and 100.0% of tumors grew in IA NK, IA saline, and IV NK groups, respectively; initial tumor diameters were not different between groups (p=0.15), but final tumor diameters were different between all groups (p Conclusion The intrahepatic distribution of SPIO-labeled NKs was quantitatively visualized with MRI, and both labeled NK delivery as measured by histology and MRI were well-correlated with tumor response as determined by change in tumor diameter, with IA NKs demonstrating the strongest response. The developed techniques demonstrate potential for the adjustment of patient-specific therapeutic regimens during AIT for the treatment of HCC.

Tumor Size on Abdominal MRI Versus Pathologic Specimen in Resected Pancreatic Adenocarcinoma: Implications for Radiation Treatment Planning

We assessed the accuracy of abdominal magnetic resonance imaging (MRI) for determining tumor size by comparing the preoperative contrast-enhanced T1-weighted gradient echo (3-dimensional [3D] volumetric interpolated breath-hold [VIBE]) MRI tumor size with pathologic specimen size. The records of 92 patients who had both preoperative contrast-enhanced 3D VIBE MRI images and detailed pathologic specimen measurements were available for review. Primary tumor size from the MRI was independently measured by a single diagnostic radiologist (P.M.) who was blinded to the pathology reports. Pathologic tumor measurements from gross specimens were obtained from the pathology reports. The maximum dimensions of tumor measured in any plane on the MRI and the gross specimen were compared. The median difference between the pathology sample and the MRI measurements was calculated. A paired t test was conducted to test for differences between the MRI and pathology measurements. The Pearson correlation coefficient was used to measure the association of disparity between the MRI and pathology sizes with the pathology size. Disparities relative to pathology size were also examined and tested for significance using a 1-sample t test. The median patient age was 64.5 years. The primary site was pancreatic head in 81 patients, body in 4, and tail in 7. Three patients were American Joint Commission on Cancer stage IA, 7 stage IB, 21 stage IIA, 58 stage IIB, and 3 stage III. The 3D VIBE MRI underestimated tumor size by a median difference of 4 mm (range, -34-22 mm). The median largest tumor dimensions on MRI and pathology specimen were 2.65 cm (range, 1.5-9.5 cm) and 3.2 cm (range, 1.3-10 cm), respectively. Contrast-enhanced 3D VIBE MRI underestimates tumor size by 4 mm when compared with pathologic specimen. Advanced abdominal MRI sequences warrant further investigation for radiation therapy planning in pancreatic adenocarcinoma before routine integration into the treatment planning process.

Tumor Size on Abdominal MRI Versus Pathologic Specimen in Resected Pancreatic Adenocarcinoma: Implications for Radiation Therapy Planning

Tumor Size on Abdominal MRI Versus Pathologic Specimen in Resected Pancreatic Adenocarcinoma: Implications for Radiation Therapy Planning

Diagnostic Accuracy of MRI in Primary Cervical Cancer

Introduction: Magnetic resonance imaging (MRI) studies obtained during the initial staging of patients affected by uterine cervical cancer were compared to the final histological report after surgery. Methods: Data were retrieved from published papers. Results: MRI detection of lymph node metastases shows a sensitivity of 49.3% (1209 patients) and a specificity of 87.7% (1182 patients). Parametrial involvement detection has 66.2% sensitivity (1288 patients) and 83.6% specificity (1282 patients). MRI tumor size evaluation shows significant error. Even detection of over 1 cm diameter primary tumor can fail. MRI appears promising in the detection of myometrial and endometrial involvement. Conclusions: Primary uterine cervical cancer evaluation with routine MRI has a limited accuracy especially in the detection of lymph node involvement and parametrial invasion. It is not sensitive enough to replace histology of dissected nodes and parametria. Tumor size estimation is imprecise. Detection of myometrial and endometrial invasion using MRI might be possible. Awareness of MRI limitations is crucial in primary cervical cancer staging.

MRI Staging After Neoadjuvant Chemotherapy for Breast Cancer: Does Tumor Biology Affect Accuracy?

A discrepancy often exists between the post-neoadjuvant chemotherapy (NAC) breast tumor size on magnetic resonance imaging (MRI) and pathologic tumor size. We seek to quantify this MRI/pathology discrepancy and determine if the accuracy of MRI post NAC varies with tumor subtype. The University of Pittsburgh Medical Center (UPMC) Cancer Registry and radiology database were searched for patients with breast cancer who underwent NAC and MRI staging between 2004 and 2009. We compared radiologic to pathologic staging and stratified differences based on tumor biology using univariate, multivariate, and receiver operating characteristic (ROC) analysis. Two hundred three of 592 patients undergoing surgery after NAC for breast cancer had MRI staging pre and post chemotherapy. All patients had intact tumors prior to the initiation of chemotherapy. Average tumor size by MRI was 4.0 cm pre chemotherapy and 1.2 cm post chemotherapy. The average pathologic tumor size was 1.7 cm (range 0-13 cm). The difference between MRI and pathologic tumor size was greatest in luminal (1.1 cm) and least in triple-negative (TN) and human epidermal growth factor receptor 2 (HER2)-positive tumors (<0.1 cm) (p = 0.015). MRI was a good discriminator for pathologic complete response (pCR) [area under the curve (AUC) 0.777]. Its predictive value for pCR was much greater in TN and estrogen receptor(ER)-/HER2+ than in luminal tumors (73.6 vs. 27.3%). MRI is an effective tool for predicting response to NAC. The accuracy of MRI in estimating postchemotherapy tumor size varies with tumor subtype. It is highest in ER-/HER2+ and TN and lowest in luminal tumors. Knowledge of how tumor subtype affects MRI accuracy can guide recommendations for surgery following NAC.

Abstract P2-02-09: The Effect of Breast-MRI in Work-Up of Primary Operable Breast Cancer

Abstract Background: Breast magnetic resonance imaging (MRI) is becoming an often-utilized examination in the preoperative planning for breast cancer. However, it is not yet accepted as a routine examination for all breast cancer patients due to the lack of data regarding whether breast MRI has any effect on recurrence or survival. Aim: The aim of this study is to evaluate the effect of MRI on surgical management in operable breast cancer. Methods: From April 2008 till January 2010 consecutive primary operable breast cancer patients had a preoperative breast-MRI in addition to regular mammography and ultrasonography. Additional lesions newly found by MRI were evaluated with a target ultrasound and if needed biopsied. Moreover MRI tumor size was compared to mammographic and ultrasonographic tumor size. Blinded for MRI results and the performed surgical plan, surgical management based on traditional radiological work-up was determined retrospectively by 2 surgeons. Change of surgical plan by MRI was subsequently analysed. Accuracy of MRI based surgical plan was evaluated by comparing definitive pathology. Results Hundred ninety eight consecutive patients were analyzed. Median age was 59 years (23-82). Additional ipsilateral and contralateral suspicious lesions were detected by MRI in 53 patients (27%). Twenty two patients had additionally target-ultrasonography: 5 lesions were not found, 4 lesions had benign aspect. Five out of 13 biopsied patients had second breast cancer, 3 patients had contralateral breast cancer and 2 patients had multicentric breast cancer. In 31 patients no further evaluation was performed because the new focus was supposed to be a satellite (n=12) or mastectomy was already chosen to be done (n=19). There was a change in surgical plan due to MRI results in 35 of 198 patients (18%), all of whom received more extensive surgery than previously planned: in 17 patients mastectomy was performed instead of lumpectomy, 15 patients had a more extensive lumpectomy. Three patients had contralateral surgery for breast cancer. In 24 patients (69%) MRI based surgical plan was confirmed by definitive pathology. In 11 patients MRI overestimated tumor size or misinterpreted a satellite lesion. Conclusion. Breast MRI contributes to a significantly change of surgical plan. However, false-positive findings are frequent. Therefore, in unselected primary operable breast cancer patients routine implementation of breast MRI is not right away justified. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-02-09.

Is there a Role for MRI in the Preoperative Assessment of Patients with DCIS?

Breast magnetic resonance imaging (MRI) is used to identify residual and additional disease in patients with invasive carcinoma. The use of MRI in assessing extent of disease for ductal carcinoma in situ (DCIS) is less well defined. This study assessed the value of MRI in the preoperative evaluation of DCIS. We identified 98 patients with DCIS in 2007. Of these, 63 underwent stereotactic biopsy, followed by MRI. There were 35 who underwent stereotactic biopsy alone. Concordance between MRI and histopathology was defined as the presence or absence of residual disease. There was no significant difference in mastectomy rates between the MRI and non-MRI group (20.3% vs 25.7%, P = .62). In patients undergoing breast-conserving surgery (BCS), there were fewer positive margins in the MRI versus the non-MRI group (21.2% vs 30.8%, P = .41). Of the 64 cases that underwent preoperative MRI, 43 (67.2%) were concordant. Also, 15 of 43 cases (34.8%) had MRI results that accurately predicted pathologic size. In 28 of 43 patients (65.2%), MRI overestimated disease in 20, by a mean of 1.97 cm. In patients with MRI tumor size >2 cm, MRI overestimated disease by a mean of 3.17 cm. Of the 64 cases, 21 (32.8%) were discordant. Also, 10 of 21 (47.6%) had a positive MRI and no residual disease on histopathology, and 11 of 21 (52.3%) had negative MRI and residual disease on pathology. MRI does not accurately predict extent of disease in patients with extensive DCIS. In patients with MRI tumor size < or = 2 cm, MRI may assist in surgical planning. MRI results in patients with DCIS should be interpreted with caution; decision for mastectomy should not be made on MRI findings alone.

A Combined Pharmacokinetic and Radiologic Assessment of Dynamic Contrast-Enhanced Magnetic Resonance Imaging Predicts Response to Chemoradiation in Locally Advanced Cervical Cancer

To investigate the combination of pharmacokinetic and radiologic assessment of dynamic contrast-enhanced magnetic resonance imaging (MRI) as an early response indicator in women receiving chemoradiation for advanced cervical cancer. Twenty women with locally advanced cervical cancer were included in a prospective cohort study. Dynamic contrast-enhanced MRI was carried out before chemoradiation, after 2 weeks of therapy, and at the conclusion of therapy using a 1.5-T MRI scanner. Radiologic assessment of uptake parameters was obtained from resultant intensity curves. Pharmacokinetic analysis using a multicompartment model was also performed. General linear modeling was used to combine radiologic and pharmacokinetic parameters and correlated with eventual response as determined by change in MRI tumor size and conventional clinical response. A subgroup of 11 women underwent repeat pretherapy MRI to test pharmacokinetic reproducibility. Pretherapy radiologic parameters and pharmacokinetic K(trans) correlated with response (p < 0.01). General linear modeling demonstrated that a combination of radiologic and pharmacokinetic assessments before therapy was able to predict more than 88% of variance of response. Reproducibility of pharmacokinetic modeling was confirmed. A combination of radiologic assessment with pharmacokinetic modeling applied to dynamic MRI before the start of chemoradiation improves the predictive power of either by more than 20%. The potential improvements in therapy response prediction using this type of combined analysis of dynamic contrast-enhanced MRI may aid in the development of more individualized, effective therapy regimens for this patient group.