Is capsular retraction a specific CT sign of malignant liver tumor?

The aim of this study was to assess if a liver capsular retraction is a specific CT sign in malignant hepatic tumors. The authors reviewed retrospectively 320 hepatic CT scans obtained in 300 patients during a 3-year period. These patients presented with benign (n = 64) or malignant (n = 236) hepatic tumors. In 7 patients we found retraction of the capsule surrounding the tumor. All these tumors were histologically proven as malignant lesions: 4 metastases (none being chemically treated), 2 peripheral cholangiocarcinomas, and 1 epithelioid hemangioendothelioma. The prevalence of this sign was 2.18 % (7 of 320) in this series. This capsular retraction pattern has never been found in hepato-cellular carcinomas (no fibrolamellar in this series) and benign lesions. Liver capsular retraction is an uncommon but specific (100 %) sign in malignant hepatic tumors; however, a larger and prospective series is needed. Received: 7 August 1998; Revision received: 2 October 1998; Accepted: 27 January 1999     

MRI findings in intramuscular lipomas

Objective. To investigate the spectrum of magnetic resonance (MR) findings of intramuscular lipoma. Design and patients. A retrospective review of 17 consecutive cases of intramuscular lipoma examined with MR imaging was undertaken. Features assessed included the size and margin of the mass; the homogeneity of the contents, including the presence or absence of intermingled muscle fibers; whether the mass was uninodular or multinodular; and the presence of linear structures between and within the tumor nodules. Three well-differentiated liposarcomas and one dedifferentiated liposarcoma associated with lipoma-like components were also studied to allow a comparison of the benign and malignant lesions. Results. The diameter of the intramuscular lipomas varied from less than 3 cm to more than 10 cm. Ten of the intramuscular lipomas were homogeneous but the remaining seven were inhomogeneous with intermingled muscle fibers within the mass. The intramuscular lipomas were well defined in 12 cases, and infiltrative in five. In one case the margin of the lesion showed prominent infiltration of the surrounding muscle tissue. Of the 17 cases of intramuscular lipoma, 15 were composed of a single nodule, whereas three of four cases of liposarcoma were composed of multinodular masses. Conclusion. The MR findings of intramuscular lipoma varied from a small, single and homogeneous mass identical to ordinary (superficial) lipoma, to a large, inhomogeneous lesion with an infiltrative margin. The presence of infiltrative margins and intermingled muscle fibers in intramuscular lipoma indicates a benign lesion rather than malignancy. In addition, uninodularity of the mass is helpful in differentiating intramuscular lipoma from well-differentiated liposarcoma. Received: 26 May 1998 Revision requested: 7 August 1998 Revision received: 10 November 1998 Accepted: 16 November 1998     

Diffusivity Measurements Differentiate Benign from Malignant Lesions in Patients with Peripheral Neuropathy or Plexopathy

BACKGROUND AND PURPOSE:Peripheral nerve disorders caused by benign and malignant primary nerve sheath tumors, infiltration or compression of nerves by metastatic disease, and postradiation neuritis demonstrate overlapping features on conventional MR imaging but require vastly different therapeutic approaches. We characterize and compare diffusivities of peripheral nerve lesions in patients undergoing MR neurography for peripheral neuropathy or brachial or lumbosacral plexopathy.MATERIALS AND METHODS:Twenty-three patients, referred for MR neurography at our institution between 2003 and 2009 for a peripheral mononeuropathy or brachial or lumbosacral plexopathy and whose examinations included DWI, received a definitive diagnosis, based on biopsy results or clinical and imaging follow-up, for a masslike or infiltrative peripheral nerve or plexus lesion suspicious for tumor. Mean ADC values were determined within each lesion and compared across 3 groups (benign lesions, malignant lesions, and postradiation changes).RESULTS:Both ANOVA and Kruskal-Wallis tests demonstrated a statistically significant difference in ADC values across the 3 groups (P = .000023, P = .00056, respectively). Post hoc pair-wise comparisons showed that the ADC within malignant tumors differed significantly from that within benign tumors and postradiation changes. ADC within benign tumors and postradiation changes did not differ significantly from each other.CONCLUSIONS:DWI may be highly effective for the differentiation of benign from malignant peripheral nerve masslike or infiltrative lesions.

Peripheral neuropathies can be divided into mononeuropathies, polyneuropathies, and plexopathies. Patients present with pain, sensory symptoms, and/or motor deficits in the distribution of a single peripheral nerve, multiple peripheral nerves, or a nerve plexus. Mononeuropathies affect a single peripheral nerve. Polyneuropathies affect multiple peripheral nerves. In plexopathies, symptoms are localized to the brachial or lumbosacral plexus.Polyneuropathies are generally attributable to systemic diseases (eg, diabetes and vitamin deficiencies), while mononeuropathies are most often due to trauma, nerve compression syndromes that occur at a few characteristic anatomic locations, or mass lesions. History and physical examination, supplemented in a subset of cases by laboratory studies, electrodiagnostic studies, and neuroimaging, are the main tools for diagnostic evaluation. In patients with a classic compression mononeuropathy, such as median nerve compression at the carpal tunnel, the diagnosis can often be made clinically and corroborated by needle electromyography, nerve conduction, and/or imaging studies.^1–4 For mononeuropathies involving nerves not typically susceptible to compression syndromes, imaging can play an essential role in identifying the lesion and guiding management.Plexopathies give rise to motor and/or sensory deficits in an extremity. Most brachial plexopathies (75%) are attributable to postradiation changes, primary and metastatic lung cancer, or metastatic breast cancer.⁵ Common causes of lumbosacral plexopathy are primary and metastatic tumor, including cervical, endometrial, ovarian, prostate, testicular, and colorectal cancer; postradiation changes; and diabetes.⁶ For patients with a history of radiation for malignancy, recurrent tumor with nerve invasion must be distinguished from radiation plexopathy; both can develop months to years following therapy and can have similar clinical presentations.⁶Although benign and malignant primary nerve sheath tumors, infiltration of nerves by metastatic disease, and postradiation neuritis require different therapeutic approaches, they also demonstrate overlapping features on MR imaging, including T2 hyperintensity, focal enlargement, and enhancement.^7,8 Diffusivity measurements from DWI may be helpful in differentiating distinct pathologic entities. In prior studies, DWI was useful in differentiating malignant and benign peripheral nerve sheath tumors,⁹ retroperitoneal masses,¹⁰ head and neck tumors,^11,12 and lymph nodes.^13,14 Other studies have demonstrated differences in the diffusivities of adult¹⁵ or pediatric brain tumors¹⁶ that correlate with tumor grade and/or histologic type. In this study, we focus on masslike or infiltrative lesions of the peripheral nerves detected by MR imaging in patients presenting clinically with a peripheral mononeuropathy or plexopathy. We characterize and compare the diffusivities of these lesions and demonstrate significant differences among benign and malignant peripheral nerve tumors and postradiation changes.     

Differentiation of soft tissue benign and malignant peripheral nerve sheath tumors with magnetic resonance imaging

PURPOSE: The objective of this study was to differentiate the magnetic resonance (MR) imaging appearance of benign peripheral nerve sheath tumors (PNSTs) from that of malignant PNSTs. MATERIALS AND METHODS: Twenty-six patients who underwent MR imaging and had a histologic diagnosis of benign (schwannoma, n=16; neurofibroma, n=1) or malignant (n=9) PNST were retrospectively reviewed. The size, location, shape, margin, and signal intensities of the tumors on precontrast and gadolinium-enhanced MR imaging were analyzed. In each patient, the presence or absence of split fat, target, and fascicular signs was determined. RESULTS: The mean size of the benign PNSTs (3.4 cm, S.D.=2.5 cm) was significantly smaller than that of the malignant tumors (8.2 cm, S.D.=3.1 cm) (P<.001). Seventeen (65.4%) of the 26 tumors were spindle shaped or ovoid (12 benign and 5 malignant tumors). Contiguity with specific nerves was identified in 15 (88.2%) of the 17 benign PNSTs but in none of the malignant tumors (P<.05). Well-defined margins were noted in all 17 benign PNSTs but in only 3 (33.3%) of the 9 malignant tumors (P<.001). Five (55.6%) of the 9 malignant PNSTs but none of the benign tumors showed signal intensity change in adjacent soft tissue (P<.05). There was no significant difference in signal intensity between the benign and malignant tumors on T(1)-weighted, T(2)-weighted, and contrast-enhanced MR images. The split fat and target signs were present more frequently in the benign PNSTs than in the malignant PNSTs (P<.05).Conclusions: Benign and malignant PNSTs are often spindle shaped. Recognition of contiguity with adjacent nerves, a well-defined margin, and the presence of the split fat sign may suggest benignity. Imaging features suggestive of malignancy can be a larger size and an infiltrative margin.     

髂骨原发囊样骨肿瘤及瘤样病变的影像学诊断

目的:分析髂骨囊样骨肿瘤及肿瘤样病变的影像学表现。方法:回顾性分析经穿刺或/和手术病理证实的46例髂骨囊样骨肿瘤及肿瘤样病变影像学表现。46例全部行X线片检查,38例行CT检查,20例行MRI检查(增强16例)。结果:46例中骨肿瘤29例,其中良性肿瘤12例(骨巨细胞瘤4例,内生软骨瘤、软骨母细胞瘤各2例,血管瘤、骨母细胞瘤、骨样骨瘤、软骨黏液样纤维瘤各1例),恶性肿瘤17例(恶性巨细胞瘤、骨恶性纤维组织细胞瘤各1例,软骨肉瘤、淋巴瘤各4例,骨肉瘤7例),肿瘤样病变17例(单纯性骨囊肿1例,邻关节骨囊肿、动脉瘤样骨囊肿、嗜酸性肉芽肿各2例,骨纤维异常增生症10例)。发病部位为髂翼39例,髋臼7例。病变主要表现为髂骨囊样骨质破坏,呈膨胀性改变30例,硬化环形成24例,病变内见钙化灶14例,软组织肿块20例。结论:常见的髂骨囊样骨肿瘤和肿瘤样病变一般都具有某些特征性的CT表现,必要时综合X线、MRI表现,可提高定性诊断符合率。     

Benign and malignant hepatocellular tumors: evaluation of tumoral enhancement after mangafodipir trisodium injection on MR imaging

The aim of this work was to study the ability of mangafodipir trisodium (Mn-DPDP)-enhanced MR imaging in differentiating malignant from benign hepatocellular tumors. Eleven patients with pathologically proved hepatocellular carcinomas, six with focal nodular hyperplasias, and one with a single hepatocellular adenoma were examined by spin-echo and gradient-echo T1-weighted sequences before, 1 h after, and 24 h after intravenous injection of Mn-DPDP (5 μmol/kg). Quantitative analysis including enhancement and lesion-to-liver contrast-to-noise ratio, and qualitative analysis including the presence of a central area and a capsule were done on pre- and post-Mn-DPDP-enhanced images. Enhancement was observed in all the tumors with significant improvement (p < 0.05) in contrast-to-noise ratio 1 h after, and 24 h after intravenous injection of Mn-DPDP. There were no significant differences in the mean enhancement and the mean contrast-to-noise ratio (CNR) between benign and malignant tumors. No enhancement was seen within internal areas observed in 7 hepatocellular carcinomas, and in 5 focal nodular hyperplasias, and within capsules which were observed in 9 hepatocellular carcinomas. In our study, Mn-DPDP increased CNR of both benign and malignant tumors but did not enable differentiation between benign and malignant tumors of hepatocellular nature. Received: 7 October 1997; Revision received: 25 February 1998; Accepted: 10 July 1998     

Enhancement of intramammary lymph nodes with lymphoid hyperplasia: a potential pitfall in breast MRI

We present three cases of breast lesions labeled as probable intramammary lymph nodes that showed an increase in size on follow-up mammography. Contrast-enhanced MRI was performed and the three lesions showed strong and rapid uptake of the intravenous contrast. Core needle biopsy established the diagnosis of lymphoid hyperplasia in all three patients. Because intramammary lymph nodes affected by benign processes can present findings similar to malignant lesions, the usefulness of contrast-enhanced MRI in these cases is controversial. Received 7 July 1997; Revision received 16 January 1998; Accepted 30 March 1998     

Contrast-enhanced three-dimensional helical CT for soft tissue tumors in the extremities

Objective. To evaluate the ability of contrast-enhanced three-dimensional (3D) helical computed tomography (CT) to image soft tissue tumors in the extremities. Design and patients. Forty-five consecutive patients with soft tissue tumors in the extremities were examined (mean age 46.2 years; 24 females, 21 males). Twenty-five patients had benign lesions and 20 had malignant lesions. All the patients underwent contrast-enhanced 3DCT scanning and magnetic resonance (MR) imaging preoperatively. All patients were surgically treated. Spiral CT scanning was performed with intravenous contrast enhancement. 3D reconstruction images were produced after thresholding, using Active-Windows (version 2.0, General Electric, Milwaukee, WI) software. 3DCT findings were compared in a masked fashion with the MR imaging and surgical findings regarding bone and major vessel invasion by the tumors. Results. Forty-four of 45 tumors were satisfactorily imaged for the interpretation of their size, location and relationship to the skeleton and major vessels. One malignant tumor was judged on 3DCT to invade the major vessel, but the vessel proved to be normal at surgery. Conclusions. Contrast-enhanced 3D helical CT can be used for the evaluation of soft tissue tumors in the extremities, for preoperative surgical planning. Received: 14 August 2000 Revision requested: 28 November 2000 Revision received: 29 December 2000 Accepted: 1 February 2001     

Retrospective review: usefulness of a number of imaging modalities including CT, MRI, technetium-99m pertechnetate scintigraphy, gallium-67 scintigraphy and F-18-FDG PET in the differentiation of benign from malignant parotid masses

Objective The aim of this study is to evaluate an imaging approach using computed tomography (CT), magnetic resonance imaging (MRI), technetium-99m pertechnetate scintigraphy (^99mTc pertechnetate scintigraphy), gallium-67 scintigraphy (⁶⁷Ga scintigraphy) and fluorine-18 fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET). Material and Methods We reviewed retrospectively 59 patients with parotid masses. CT, MRI,⁶⁷Ga scintigraphy,^99mTc pertechnetate scintigraphy, and¹⁸F-FDG PET were performed. Results All of the benign tumors had smooth margins on CT and MRI. Patients with inflammatory lesions and malignant lesions showed well-defined margins or ill-defined margins. All Warthin's tumors showed high technetium accumulation. Many of malignant tumors showed high FDG accumulation. Both pleomorphic adenomas and Warthin's tumors showed high accumulation in some cases on¹⁸F-FDG PET. Among 15 patients with pleomorphic adenoma, 14 patients showed marked hyperintensity relative to CSF on T2-weighted images and partial enhancement on contrast-enhanced T1-weighted images. Combination of several imaging modarity offered usefulness of differential diagnosis for parotid masses. Conclusion An efficient combination of imaging methods may be helpul for achieve the correct diagnosis.     

Critical evaluation of the specificity of MRI and TVUS for differentiation of malignant from benign adnexal lesions

The aim of our work was to study the specificity of MRI in comparison with transvaginal US for differentiation of malignant from benign adnexal lesions. A total of 67 patients with clinically suspicious adnexal lesions were evaluated by MRI. Transaxial and coronal images were acquired using T1-weighted sequences before and following IV contrast and T2-weighted sequences. In all patients transvaginal ultrasound examinations (TVUS) were performed. For both imaging modalities each lesion was classified separately as either benign or malignant according to previously published criteria. Pathologic findings were available in 65 cases. Both MRI and TVUS correctly classified the 12 malignant lesions (sensitivity 100 %). Specificity (MRI: 78.2 %, TVUS: 65.5 %) and accuracy (MRI: 82 %, TVUS: 71.6 %) were higher with MRI than with TVUS, but differences were statistically not significant (p = 0.18 and p = 0.20, chi-square test). There was agreement/disagreement between findings of MRI and US in 52/15 lesions. The macroscopic criteria for malignancy are unspecific and result in a limitation of the specificity of both MRI and TVUS. The MRI technique is a valuable adjunct to TVUS by enabling further clarification of adnexal tumors with equivocal complex or solid vaginal sonographic findings. Received 6 December 1996; Revision received 17 March 1997; Accepted 9 April 1997     

Benign vascular lesions of bone: radiologic and pathologic features

 The benign vascular tumors of bone represent a diverse group of tumors that can present with a broad spectrum of clinical signs and symptoms. They can also present a significant diagnostic challenge due to their widely variable radiographic imaging and histologic features. Some of the tumors manifest as clearly benign lesions with tissue-specific diagnostic imaging features, while others have non-specific imaging features that may simulate malignant neoplasm. This article will provide a review of the nomenclature and the characteristic radiographic and pathologic features of the benign vascular lesions of bone. The information will aid in improving our diagnostic accuracy and enhance our understanding of the biologic potential of this diverse group of osseous lesions. Received: 14 May 1999 Revision requested: 17 June 1999, 6 October 1999 Revision received: 27 October 1999 Accepted: 27 October 1999     

CT扫描在甲状腺肿瘤诊断中的意义

目的分析甲状腺肿瘤的CT表现，对照病理结果，评价CT扫描对甲状腺良、恶性肿瘤鉴别诊断的价值。方法对56例甲状腺肿瘤患者增强前后CT图像进行综合分析，所有病例均经活检或手术病理证实。其中，良性病变25例，包括腺瘤14例及结节性甲状腺肿11例；恶性病变31例，包括乳头状癌19例，滤泡癌12例。结果良性病变边界比较清晰，形态较规整；恶性者边缘不清，密度不均匀，与周围结构分界不清，可见颈部淋巴结增大；良、恶性病变内均可见钙化、囊变、出血性改变。结论CT扫描是检查甲状腺病变的有效方法，对甲状腺病变的良、恶性鉴别诊断具有一定的价值。     

Differentiation of benign and malignant tumors of the parotid gland: value of pulsed Doppler and color Doppler sonography

To establish criteria for the differentiation of benign and malignant tumors of the parotid gland using color Doppler sonography (CDS) and pulsed Doppler sonography (PDS) we examined 37 patients with parotid tumors by gray-scale ultrasound, CDS, and PDS. Tumor vascularization displayed by CDS was graded subjectively on a 4-point scale (0 = no vascularization, 3 = high vascularization). From the Doppler spectrum, the highest systolic peak flow velocity, the resistive index (RI), and the pulsatility index (PI) were calculated. There were 11 malignant and 26 benign tumors. Tumor vascularization by CDS was grade 0 or 1 in 88.5 % of benign lesions, whereas it was grade 2 or 3 in 82 % of malignant lesions (P < 0.0001). The highest systolic peak flow velocity was statistically significantly higher in malignant lesions than in benign lesions. Using a threshold systolic peak flow velocity of 25 cm/s, sensitivity was 72 % and specificity was 88 % for the detection of a malignant tumor. Evaluation of tumor vascularization by CDS and PDS cannot differentiate between benign and malignant parotid tumors with certainty. However, high vascularization and high systolic peak flow velocity in tumor vessels should raise the suspicion of malignancy, even if tumor morphology on gray-scale sonography indicates a benign lesion. Received 5 February 1998; Accepted 5 March 1998     

Fibroma of tendon sheath of the infrapatellar fat pad

We report on a 13-year-old boy who was found to have a fibroma of the tendon sheath associated with the patellar tendon and within Hoffa’s fat pad of the knee. This benign tumor has never been described in this location previously. The MRI characteristics are correlated with the histologic findings. Received: 20 November 1998 Revision requested: 17 December 1998 Revision received: 16 February 1999 Accepted: 19 February 1999     

CT对腮腺病变的诊断价值

目的:评价CT对腮腺良恶性病变的诊断价值。方法:回顾性分析经手术病理证实的47例腮腺病变的CT表现。良性36例,恶性11例。CT平扫46例,增强扫描38例。结果:良性肿瘤无侵袭性,边缘清楚,密度均匀或不均匀,有钙化、囊变、坏死;炎性肿块者,灶周可有磨玻璃影,呈晕征;恶性肿瘤具有不同程度的侵袭性,多呈分叶状,不规则或浸润性生长,边缘不清。CT对腮腺病变定位准确率100% ,而对良恶性定性诊断符合率分别为恶性组72.7% ,良性组80.6% 。结论:CT对腮腺病变定位、定性诊断,特别是区别良恶性病变方面具有较高的价值     

99 Tcm-MIBI与99Tcm-MDP骨显像诊断 骨良恶性病变的比较

目的　对比分析99Tcm 甲氧基异丁基异腈 (MIBI)和99Tcm 亚甲基二膦酸盐 (MDP)对骨良恶性病变的诊断价值和疗效评估。方法　 6 1例临床拟诊骨良恶性病变患者分别进行 2项骨显像 ,其中 6例恶性肿瘤患者分别进行化疗前后显像。显像后均经手术、病理检查对比分析。结果　99Tcm MIBI显像 :73 %恶性肿瘤病灶肉眼见中、高度MIBI浓聚 ,6 0 %良性病灶肉眼未见MIBI聚集。恶性病灶部位与对侧正常组织放射性计数比值 (L C)即99Tcm MIBI摄取比值 (3 0 8± 1 6 7)明显高于良性病灶(1 36± 0 6 4) ,P <0 0 1。99Tcm MDP显像 :大多数恶性或良性病灶肉眼见中、高度MDP浓聚 ,但恶性病灶99Tcm MDPL C(3 76± 1 37)与良性病灶L C(3 10± 1 0 5 )比较差异无显著性 (P >0 0 5 )。化疗可以抑制99Tcm MIBI摄取 ,99Tcm MIBI摄取程度与99Tcm MDP比较能较好反应治疗效果。结论　99Tcm MIBI对鉴别诊断良恶性骨病和评估疗效有较好的应用价值 ,与99Tcm MDP显像联合应用可更全面地提供信息     

骨良性肿瘤与肿瘤样病变的MR诊断

目的：探讨磁共振在骨良性肿瘤与肿瘤样病变诊断中的价值。材料和方法：搜集骨良性肿瘤与肿瘤样病变３４例，分析其磁共振表现。全部病例均做磁共振检查。采用常规ＳＥ序列，Ｔ１Ｗ及Ｔ２Ｗ成像。其中２０例同时做了脂肪抑制成像。结果：磁共振诊断正确率为９４．１％（３２／３４）。磁共振征象包括：骨质破坏（３０／３４）；软组织肿块（３／３４）；关节侵犯（１／３４）；骨壳（１０／３４）；硬化缘（１７／３４）；钙化（３／３４）；骨间隔（７／３４）；囊变坏死（８／３４）；出血（７／３４）；软组织水肿（３／３４）；髓腔水肿（３／３４）；关节积液（３／３４）。结论：磁共振是骨良性肿瘤与肿瘤样病变的有效辅助诊断方法。磁共振与平片、ＣＴ相结合有利于提高定性诊断正确率。     

Bleomycin labelled with 99mTc for differentiation of breast tumors

Bleomycin labelled with ^99mTc was used to differentiate benign and malignant breast tumors. Breast scintigraphy was performed 15 and 60 min following the IV injection of 5 mCi^99mTc bleomycin. Thirty-two patients with breast tumor (14 carcinomas and 18 benign nodular lesions) were examined. Cytologic or histologic verification of the tumor was carried out in all cases. All malignant tumors of the breast in the investigated group of patients revealed significantly increased accumulation of ^99mTc-bleomycin.     

MR imaging of a case of adenomatoid tumor of the adrenal gland

The aim of this case report is to describe the appearance on magnetic resonance imaging (MRI) of an incidentally found adenomatoid tumor of the adrenal gland, and to evaluate the utility of MRI in characterizing this type of tumor. The appearance of the tumor was nonspecific on T1-weighted in-phase, opposed-phase, and T2-weighted images, as well as its behavior after paramagnetic contrast administration, outlining the differential diagnosis among carcinoma, metastatic tumors, and pheochromocytoma. After surgery, the pathologic diagnosis was adenomatoid benign tumor of mesothelial origin. Although MRI enables the characterization of most benign lesions of the adrenal gland, the appearance of other lesions is nonspecific. In our case, MRI did not assist in preoperative diagnosis, guiding us towards a diagnosis of malignancy. Received: 16 February 1998; Revision received: 17 April 1998; Accepted: 12 May 1998     

The diverse pathology and kinetics of mass, nonmass, and focus enhancement on MR imaging of the breast

Purpose:

To compare the pathology and kinetic characteristics of breast lesions with focus‐, mass‐, and nonmass‐like enhancement.

Materials and Methods:

A total of 852 MRI detected breast lesions in 697 patients were selected for an IRB approved review. Patients underwent dynamic contrast enhanced MRI using one pre‐ and three to six postcontrast T₁‐weighted images. The “type” of enhancement was classified as mass, nonmass, or focus, and kinetic curves quantified by the initial enhancement percentage (E₁), time to peak enhancement (T_peak), and signal enhancement ratio (SER). These kinetic parameters were compared between malignant and benign lesions within each morphologic type.

Results:

A total of 552 lesions were classified as mass (396 malignant, 156 benign), 261 as nonmass (212 malignant, 49 benign), and 39 as focus (9 malignant, 30 benign). The most common pathology of malignant/benign lesions by morphology: for mass, invasive ductal carcinoma/fibroadenoma; for nonmass, ductal carcinoma in situ (DCIS)/fibrocystic change(FCC); for focus, DCIS/FCC. Benign mass lesions exhibited significantly lower E₁, longer T_peak, and lower SER compared with malignant mass lesions (P < 0.0001). Benign nonmass lesions exhibited only a lower SER compared with malignant nonmass lesions (P < 0.01).

Conclusion:

By considering the diverse pathology and kinetic characteristics of different lesion morphologies, diagnostic accuracy may be improved. J. Magn. Reson. Imaging 2011;33:1382–1389. © 2011 Wiley‐Liss, Inc.