Diffusion weighted MRI and spectroscopy in invasive carcinoma of the breast at 3Tesla. Correlation with dynamic contrast enhancement and pathologic findings.

BACKGROUND: The most common histological types of invasive breast carcinomas are the invasive ductal carcinoma (IDC) and the invasive lobular carcinoma (ILC). The purpose of our study was to evaluate the role of the diffusion-weighted imaging (DWI) and the in vivo proton magnetic resonance spectroscopy (1H-MRS ) at 3 Tesla magnet in invasive breast cancer and correlate them with the dynamic contrast enhancement (DCE) and pathologic findings. METHODS: We retrospectively studied at 3Tesla magnet the apparent diffusion coefficient (ADC) values, the detection of choline in the 1H-MRS and the kinetic analyses obtained after DCE in 181 patients with histologically confirmed invasive breast carcinomas. Among these patients, 160 had IDC and 21 ILC. We used the DWI sequence with a b value of 1,000 mm2/sec for the calculation of the ADC value, the fat-suppressed point-resolved spectroscopy (PRESS) sequence in order to evaluate the existence of a choline peak in the spectrum and the T1W GRE FAT SAT VIBRANT sequence for the characterization of the kinetic curves. Finally, we correlated the pathologic type of invasive cancer, as well as the type of the kinetic curve with the ADC value and the detectability of choline resonance in the spectrum in each of the 181 patients. RESULTS: The ADC values in the 158 out of 160 IDC patients, ranged from 0.5 x 10-3 to 1.2 x 10-3 mm2/sec, with 78.1 % having ADC value of 1 x 10-3 mm2/sec. Regarding the 1H-MRS, in 121 out of 160 IDC patients, choline was found in 72.3 %. The ADC values in the 21 ILC patients also ranged from 0.5 x 10-3 to 1.2 x 10-3 mm2/sec with 57.1 % having ADC value of 1 x 10-3 mm2/sec. Regarding the 1H-MRS, in 10 out of 21 ILC patients, detection of choline was positive in 60 % of them. In the 21 ILC patients, the kinetic analysis after the dynamic administration of contrast medium showed type I (persistent) curve in 4.3 %, type II (plateau) curve in 33.3 % and type III (washout) in 52.4 %. In the 158 IDC patients (missing in two cases) type I curve was obtained in 0.63 %, type II in 19.4 % and type III in 80 %. From the correlation analysis of the IDC results using Kruskal-Wallis Test and the non-parametric Kendall's tau-b test, the curve type was positively associated (Kendal tau-b: 0.254, p =0.005) with the presence of choline, while the ADC value was negatively associated (Kendal tau-b: -0.224, p =0.011) with the presence of choline. In the ILC cases, the sample was insufficient for the correlation to become statistically significant. However, the ADC values tended to be lower in IDC patients (78.1 % having ADC value 1 x 10-3 mm2/sec) compared to ILC (57.1 % having ADC value 1 x 10-3 mm2/sec). Choline was more commonly detected in the IDC (72.3 %) than ILC (60 %) patients. CONCLUSION: Our results are consistent with previous findings that both ADC values and choline detection in the spectrum play a significant role in establishing the final diagnosis of malignancy, especially when the kinetic pattern of enhancement is misleading. Hippokratia 2016, 20(3): 192-197.

Imaging Findings of an Epidermoid Cyst Undergoing Malignant Transformation.

Malignant transformation of epidermoid cyst into squamous cell carcinoma (SCC) is rare. We report the case of a 39-year-old woman presenting with dizziness and cerebellar ataxia. MR scan revealed a mass in the left cerebropontine angle compressing the brainstem and the cerebellum, with two main components, a cystic and a solid one. The cystic component displayed imaging findings consistent with an epidermoid cyst. The solid component showed dense calcifications, low signal intensity on T1W, T2W and DW images and peripheral nodular enhancement. MR spectroscopy detected high lipid/lactate peaks and choline/creatine ratio. Imaging findings raised suspicion for malignant transformation, which was confirmed by histopathologic examination revealing an SCC. MR imaging with intravenous administration of gadolinium, DW images and MR spectroscopy can play a critical role in the diagnosis of malignant transformation of an epidermoid cyst.

CT and MR imaging findings in cerebral toxocaral disease.

We report serial MR findings in a 54-year-old woman with eosinophilic meningoencephalitis due to Toxocara canis infection, a parasitic disease contracted through exposure with soil contaminated by the eggs of the roundworm. MR imaging revealed several enhancing subcortical and white matter lesions in both lobes. Antihelminthic chemotherapy yielded marked improvement of the neurologic deficits and cerebral lesions. The specific MR findings-low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, and contrast enhancement-and the clinical and epidemiologic features of CNS involvement are herein reviewed.

Lipomatous tumors of soft tissue: MR appearance with histological correlation.

There is a broad spectrum of lipomatous tumors that involve soft tissues including ordinary lipomas, variants of lipomas, heterotopic lipomas, lipomatosis, hibernomas and liposarcomas. The recognition of these tumors is important to avoid diagnostic pitfalls. The MR imaging appearance of the lesion, including location, shape and internal architecture, suggests the diagnosis of lipomatous tumors. The signal intensity on T1-, T2-, fat-suppressed T2-weighted (FS-T2) images or short tau inversion recovery (STIR), T1- and fat-suppressed T1-weighted images after Gd-DTPA administration can be a useful aid in distinguishing between biologically different types of lipomatous tumors. The imaging features are often characteristic and reflect the histological pattern of the tumors. We present an overview of the lipomatous tumors and we correlate MR imaging appearance with histological findings.

Foci of decreased signal on T2-weighted MR images in leiomyosarcomas of soft tissue: correlation between MR and histological findings.

OBJECTIVE: Leiomyosarcomas are rare soft tissue sarcomas with varying MR signal characteristics and histologic pictures. The purpose of this study was to investigate the histological features of foci, which showed decreased signal on T2-weighted images in leiomyosarcomas of soft tissue. MATERIAL AND METHODS: We reviewed the MR images of six histologically proved cases of leiomyosarcomas of soft tissue and correlated the foci, which showed decreased signal on T2-weighted images with the histologic findings. RESULT: Microscopic examination revealed that these foci were composed of hyalinization of neoplastic tissue, internal septations, deposition of hemosiderin, or corresponded to metaplastic bone. CONCLUSION: The authors explain that the foci of decreased signal on T2-weighted MR images correspond to tissue components of the lesion, particularly fibrous tissue, hemosiderin and metaplastic bone. So, the suggestion is that leiomyosarcoma should be considered in the differential diagnosis of soft-tissue tumors that show foci of decreased signal on T2-weighted MR images.

Ground-glass pattern fibrous dysplasia of frontal sinus.

The case of a 5-year-old boy with ground-glass pattern craniofacial fibrous dysplasia (FD) presenting with progressive swelling in the right frontal region is reported. The imaging findings with computed tomography and magnetic resonance imaging (MRI) findings are presented. The differential diagnosis with inspissated mucocele is discussed as well. Fibrous tissue could be hypo dense on CT. Post-contrast enhancement of the lesion on MRI is the key for diagnosis.

The clinical presentation of Von Meyenburg complexes.

Von Meyenburg Complexes (VMCs) is a rare clinicopathologic entity, consisting of small (<1.5cm), usually multiple and nodular cystic lesions. VMCs typically cause no symptoms or disturbances in liver function and thus in most instances they are diagnosed incidentally. We present four VMCs cases, each with a distinct clinical presentation. In two of our cases, VMCs caused mild, non-specific abdominal symptoms, including diffuse abdominal pain and discomfort. In the other two cases, in a 60-year-old woman and a 25-year-old man, the clinical presentation was implicative of an infectious hepatic process reminiscent of cholangitis and liver abscesses respectively. In each case the diagnosis was based on magnetic resonance imaging and magnetic resonance cholangiopancreatography findings showing multiple hyper-intense cystic nodules not communicating with the biliary tree. Physicians should be aware of the entire clinical spectrum of VMCs and its unique radiologic features in order to differentiate VMCs from other cystic liver lesions.

Meningioma growth and interferon beta-1b treated multiple sclerosis: coincidence or relationship?

Although the coincidence of multiple sclerosis (MS) and central nervous system (CNS) tumors has been reported in over 30 cases in English literature, meningioma growth was associated with interferon-beta (INF-b) treated MS only in two of them. We report the case of a 19-year-old woman with clinically possible, laboratory supported MS, and a concomitant right intraventricular tumor with magnetic resonance imaging (MRI) characteristics consistent with meningioma (similar signal with grey matter on T1 and T2-weighted images and homogenous, intense enhancement). Two years after initiation of INF-b treatment, follow-up brain MRI revealed enlargement of the intraventricular mass and relative increase in the number of white matter lesions without significant clinical deterioration. She underwent almost total resection of the mass and histology confirmed the diagnosis of papillary meningioma. Based on the immunohistochemistry results, we speculate that INF-b resulted in meningioma growth by enhancing platelet derived growth factor (PDGF) receptors or/and down-regulating transforming growth factor receptors on the tumor itself.

Mediastinal germ cell tumors: a radiologic-pathologic review.

Germ cell tumors of the mediastinum are histologically identical to those found in the testes and ovaries. Early diagnosis and treatment improve the survival rate. Imaging studies of teratoma demonstrate a rounded, often lobulated heterogeneous mass containing soft tissue elements with fluid and fat attenuation. Calcification is present in 20-43% of cases. Seminomas are large masses of homogeneous soft tissue attenuation. Malignant nonseminomatous germ cell tumors are heterogeneous tumors with irregular borders due to invasion of adjacent structures. CT shows the location and extent of the tumors as well as intrinsic elements including soft tissue, fat, fluid, and calcification. CT is the modality of choice for the diagnostic evaluation of these tumors. MRI reveals masses of heterogeneous signal intensity, is more sensitive in depicting infiltration of the adjacent structures by fat plane obliteration, and is performed as an ancillary study.

MRI findings of extramedullary haemopoiesis.

Extramedullary haemopoiesis (EH) is a compensatory process associated with chronic haemolytic anaemia. It is rare, however, for such an abnormality to cause spinal cord compression. We present two patients with known beta-thalassaemia intermedia who developed spinal cord compression due to masses of extramedullary haematopoietic tissue in the epidural space of the thoracic spine. The EH masses were diagnosed by MRI as an isointense epidural lesion on both T1- and T2-weighted images, compressing severely the spinal cord. After administration of a paramagnetic agent, an intermediate enhancement of the masses was evident. All the vertebral bodies had low to intermediate signal intensity as a result of displacement of fatty marrow by haematopoietic marrow. Expansion of thoracic ribs with bilateral paravertebral masses were characteristic. A small dose of radiotherapy was given and marked improvement in neurological symptoms was evident. An MRI examination established shrinkage of the mass and decompression of spinal cord. The role of MRI in diagnosis of EH masses is essential and radiation therapy is a very effective treatment for this rare complication.

Correlation of dementia, neuropsychological and MRI findings in multiple sclerosis.

Twenty patients diagnosed as having multiple sclerosis (MS) were examined by MRI and 9 neuropsychological scales: MMSE, BCRS, RMB, SDMT, BNT, VM, FAS, Benton and Hamilton. The number and distribution of the lesions, and cerebral and corpus callosum atrophy were evaluated by MRI. MR images were generated by a 0.5 Tesla instrument utilizing T1WI, PD and T2WI imaging techniques. The results reveal (1) that patients with MS are impaired in a broad range of cognitive functions but mainly memory is affected; (2) number of lesions in the corona radiata, insula and hippocampus is correlated with cognitive impairment, and (3) enlargement of the IIIrd ventricle is an indicator of memory impairment in MS patients.

CT of hemodynamically unstable abdominal trauma.

This article is an appraisal of the use of CT in the management of patients with unstable abdominal trauma. We examined 41 patients with abdominal trauma using noncontrast dynamic CT. In 17 patients a postcontrast dynamic CT was also carried out. On CT, 25 patients had hemoperitoneum. Thirteen patients had splenic, 12 hepatic, 6 pancreatic, 8 bowel and mesenteric, 12 renal and 2 vascular injuries. Seven patients had retroperitoneal and 2 patients adrenal hematomas. All but five lesions (three renal, one pancreatic, and one splenic) were hypodense when CT was performed earlier than 8 h following the injury. Postcontrast studies (n = 17), revealed 4 splenic, 3 hepatic, 1 pancreatic, 3 renal, and 2 bowel and mesenteric injuries beyond what was found on noncontrast CT. Surgical confirmation (n = 21) was obtained in 81.81% of splenic, 66.66% of hepatic, 83.33% of pancreatic, 100% of renal, 100% of retroperitoneal, and 85.71% of bowel and mesenteric injuries. The majority of false diagnoses was obtained with noncontrast studies. Computed tomography is a remarkable method for evaluation and management of patients with hemodynamically unstable abdominal trauma, but only if it is revealed in the emergency room. Contrast injection, when it could be done, revealed lesions that were not suspected on initial plain scans.

McCune-Albright syndrome. Report of a case.

The McCune Albright syndrome is seldom encountered and rarely reported in dental literature. It represents a special category of polyostic fibrous displasia associated with skin pigmentation and endocrine disturbances. We describe the case of a 9-year-old boy with the McCune Albright syndrome, who was treated for a mandibular osteolytic lesion.