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D Vanel

Publications and source records attributed to D Vanel.

At least 73 records · Page 4Linked to original sources
PubMed1997

Primary tumors of the musculoskeletal system.

The excellent soft-tissue contrast and multiplanar imaging capabilities of MR imaging have led to its emergence as the most significant advance in the imaging of musculoskeletal tumors. MR imaging is the modality of choice for local staging, evaluating response to preoperative chemotherapy, and long-term follow-up in bone tumors. MR imaging is the most effective modality for both primary staging of soft-tissue malignancy and detecting recurrences. This article reviews the role of conventional spin echo techniques versus newer techniques, and then discusses the indications in the diagnosis, staging, evaluation of preoperative chemotherapy, and detection of recurrences in bone and soft-tissue tumors.

Bone Neoplasms↗
PubMed1997

[Diagnosis of infraclinical lesions of the breast with dynamic MRI: results of a prospective and multicenter study].

AIM: To determine the accuracy of dynamic contrast-enhanced subfraction MRI to diagnose nonpalpable breast lesions in a prospective multicenter study. MATERIAL AND METHODS: From June to November 1994, 72 patients had a surgical biopsy for a nonpalpable breast lesion and a preoperative dynamic MR after an informed consent was obtained. MR examinations were performed on 0.5, 1 and 1.5T MR unit. Each center underwent dynamic sequences either in spin or gradient echo in T1 weighted images obtained in less than two minutes before and after injection of Gadolinium-DOTA. The presence/absence of contrast enhancement within two minutes after injection of Gadolinium were considered as positive/negative findings respectively. RESULTS: These 72 women had mammographic (n = 80) or ultrasonographic lesions (n = 2). Mammograms showed mass (n = 23), asymmetrical density (n = 2), architectural distorsion (n = 8), clustered microcalcifications (n = 47) or was normal (n = 2). Dynamic Breast MR imaging showed early contrast enhancement in 44 malignant lesions (sensitivity: 89.8%) and 13 benign lesions (specificity: 60.6%). Five intraductal carcinoma of comedo (n = 1) or non-comedo (n = 4) type did not demonstrate any early contrast enhancement. CONCLUSION: This prospective mulcentric study confirms the high sensitivity of dynamic breast MRI whatever the type of MR unit or sequences.

Adult↗
PubMed1996

CT and MR imaging of squamous cell carcinoma of the tongue and floor of the mouth.

Because contemporary treatment of oral cavity cancer involves procedures that spare the tongue and mandible, an adequate assessment of the oral cavity is essential for appropriate surgical and radiation therapy planning. Computed tomography (CT) and magnetic resonance (MR) imaging, which allow differentiation between soft tissues, are valuable tools for assessing this complex region. Their main advantage resides in their capacity to show at best the normal anatomy and the exact extent of a low-lying tumor. For display of soft tissues and tumor, MR imaging, being a multiplanar and multicontrast technique, is superior to CT. Nonenhanced T1-weighted MR imaging is better for defining the exact extent of medullary bone invasion, which appears as a low-signal-intensity area within hyperintense medullary fat. CT is optimal in detection of cortical bone invasion, which appears as an interruption or erosion of the peripheral hyperattenuating rim. Thus, in cancer of the tongue, MR imaging should be performed first. If tumor extension to the mandible is suspected (due to clinical or MR imaging findings), CT should be added. In cancer of the floor of the mouth, both MR imaging and CT should be performed in the initial work-up, especially in those cases in which there is a clinical doubt about mandibular extension of disease. The main drawback of both modalities is their lack of specificity; other methods are needed to discriminate between tumors and inflammatory or infectious diseases, particularly in the mandible. However, once the diagnosis has been confirmed histologically, treatment can be chosen based on complementary information obtained from CT and MR imaging.

Carcinoma, Squamous Cell↗
PubMed1996

MR imaging during intracavitary brachytherapy of vaginal and cervical cancer: preliminary results.

Intracavitary brachytherapy is an effective treatment for gynecologic cancers. Twelve magnetic resonance (MR) imaging studies were performed during intracavitary brachytherapy (10 initial studies and two during repeat brachytherapy) in 10 patients with clear cell adenocarcinoma (n = 9) or epithelioma (n = 1). Fifty percent of the vaginal lesions did not demonstrate high signal intensity on T2-weighted images. Individually tailored molded applicators allowed easy detection of abnormal vaginal parietal thickening on T1-weighted images: Results in seven cases were concordant with results of clinical examination, and there were no false-negative results. MR imaging was useful in controlling the relationships between the tumor and the applicator and facilitated treatment planning, since the radiation dose to the tumor volume and adjacent critical organs could be calculated accurately. Limitations of MR imaging were underestimation of superficial vaginal tumors and the inability to differentiate between tumor and inflammation after recent surgery or repeat intracavitary brachytherapy. MR imaging during intracavitary brachytherapy appears to be a useful adjunct to clinical examination.

Adenocarcinoma, Clear Cell↗
PubMed1996

Dynamic contrast-enhanced subtraction versus T2-weighted spin-echo MR imaging in the follow-up of colorectal neoplasm: a prospective study of 41 patients.

PURPOSE: To compare dynamic contrast-enhanced subtraction (DCES) and T2-weighted spin-echo (SE) magnetic resonance (MR) imaging in the differentiation of fibrosis from recurrence during the follow-up of treated colorectal neoplasms. MATERIALS AND METHODS: Forty-one patients with 39 malignant and 16 benign lesions confirmed by means of surgery (n = 23), biopsy (n = 24), or 12-month follow-up examination (n = 8) underwent DCES MR imaging and T2-weighted SE MR imaging. Enhancement of an abnormal pelvic structure within the first 90 seconds on DCES images or high signal intensity on T2-weighted SE images was considered indicative of malignancy. RESULTS: Sensitivity, specificity, and positive and negative predictive values were, respectively, 97%, 81%, 93%, and 100% for DCES MR imaging and 77%, 56%, 81%, and 56% for T2-weighted MR imaging. The number of correctly classified lesions was significantly higher with DCES imaging compared with T2-weighted imaging (P < or = .006). CONCLUSION: DCES imaging is more accurate than T2-weighted SE imaging for differentiating fibrosis from recurrence during the follow-up of treated colorectal neoplasms.

Colon↗
PubMed1996

[Retrospective analysis of 44 adrenal puncture biopsies under x-ray computed tomographic guidance].

Fourty-four CT-guided adrenal biopsies were performed on 43 patients aged 12-74 years old (mean 57 years). The results (benign adrenal tissue, malignant tissue, and nondiagnostic) were compared with outcomes. Diagnostic samples were obtained in 86% of patients. Among the 37 proved cases with diagnostic results (10 benign, 27 malignant), there were 26 true-positives, 1 false-negatives and 10 true-negatives. CT-guided adrenal biopsy had an accuracy of 82%, a sensitivity of 96%, a negative predictive value of 83%. In the 6 patients with nondiagnostic samples 1 mass proved malignant and two masses proved benign. Seven minor complications occurred in 7 patients (6 pneumothoraces and 1 retroperitoneal hemorrhage). CT-guided adrenal biopsy is a simple safe and well tolerated technique. In oncologic patients, obtaining benign adrenal tissue was highly predictive of benignity.

Adolescent↗
PubMed1995

Can clinical data help to screen patients with lymphoma for MR imaging of bone marrow?

BACKGROUND: Previous studies have suggested combining magnetic resonance (MR) imaging and biopsy in patients with lymphoma but association between MR results and clinical symptoms have never been investigated. The purpose of this retrospective study was to better delineate patients profiles requiring bone marrow (BM) imaging in lymphoma. MATERIAL AND METHODS: 50 MR studies and blind biopsies (BB) were reviewed in 40 patients with lymphoma. MR results were compared to clinical, laboratory-based and BM follow-up data to determine potential associations between MR results and these parameters. RESULTS: 46% of MR studies were abnormal with a normal BB; 2% were normal with an abnormal BB. Abnormal MR results were significantly associated with subsequent bone marrow involvement (p < 0.01). Abnormal MR studies were significantly associated with constitutional symptoms, bone pains (p < 0.05) and an elevated alkaline phosphatase level (p < 0.01). MR imaging excluded malignancy in three patients and caused therapy to be modified in three. CONCLUSION: Abnormal clinical and laboratory-based data should be used to screen patients with normal BB for MR imaging, especially in patients with Hodgkin's disease and high grade non-Hodgkin's lymphoma.

Adolescent↗
PubMed1995

Ductal carcinoma in situ: MR imaging-histopathologic correlation.

PURPOSE: To correlate histopathologic and magnetic resonance (MR) imaging findings of ductal carcinoma in situ (DCIS). MATERIALS AND METHODS: Thirty-six women with DCIS underwent preoperative contrast material-enhanced subtraction dynamic MR imaging. Concomitant early contrast enhancement in the breast parenchyma with normal vessels was considered a positive finding. The size and shape of early enhancement were correlated with the size and density packing of ducts involved by DCIS. Tumor angiogenesis in the stroma that surrounded the ducts was evaluated with immunoperoxidase staining. RESULTS: Early contrast enhancement was demonstrated in 34 patients with DCIS but not in two patients with comedo-type DCIS. Tumor angiogenesis was demonstrated in the stroma. The size and morphology of contrast-enhanced lesions significantly correlated with the size (P = .0085) and density packing of ducts involved by DCIS (P = .012). CONCLUSION: Contrast enhancement on dynamic MR images of DCIS may be due to the presence of tumor angiogenesis in the stroma.

Breast↗
PubMed1995

[Diagnosis of local breast cancer recurrences by magnetic resonance imaging].

The aim of this study is to determine the diagnostic value of magnetic resonance imaging in the diagnosis of local recurrence of breast cancer. From 1991 to 1994, 61 women were studied prospectively using magnetic resonance imaging. All examinations were made on a 1.5 Testa machine with T1 weighted images and after gadolium-dota injection and dynamic images (T1 weighted sequences every 47 seconds during injection of a gadolinium-dota bolus). All the pre-injection, images in the dynamic series were subtracted from the images after injection. A surgical biopsy was obtained in 39 patients yielding a diagnosis of local recurrence (n = 28) or a benign lesion (n = 11). Among the 28 local recurrences, pathology examination reported invasive cancer in 22 and intra-ductal carcinoma in 6. In 22 patients with normal magnetic resonance imaging, follow-up examinations were performed every 6 months. There were no local recurrences within a delay of 6 to 36 months. Twenty-six of the 28 patients with a local recurrence, cystosteatonecrosis and surgery scar tissue less than 6 months old showed contrast uptake 1 min and 34 s after gadolinium injection during the dynamic sequence. This product uptake yielded nodular images within the invasive carcinomas and linear images in the intraductal cancers. In all cases, it is easier to visualize this contrast uptake in subtraction images. In conclusion, magnetic resonance imaging is a simple reliable method for the diagnosis of local recurrence of breast cancer.

Adult↗
PubMed1994

Head and neck rhabdomyosarcomas in children: value of clinical and CT findings in the detection of loco-regional relapses.

Between 1984 and 1990, 16 children who had been treated for a histologically proven head and neck rhabdomyosarcoma developed 19 local recurrences. Fourteen relapses discovered in 11 children (group 1) were based on clinical data acquired 3 to 52 months after completion of treatment. Clinical symptoms (12 patients) or examination (2 patients) led to suspicion of a relapse. The clinical presentation of relapses and that of primary tumour were identical in eight cases. CT scans performed prior to recurrence revealed a stable 'post-therapeutic residue' without mass effect at the original site (12 patients) or was normal (2 patients). Six of these 11 children died at 1 to 15 months and five are alive 12 to 36 months after treatment of recurrence. Five relapses were discovered on CT studies 3 to 15 months after completion of treatment in the remaining five children (group 2). Clinical examination was normal in all cases. CT scans performed 3 months before recurrence showed a stable 'post-therapeutic residue' (4 patients) or was normal (1 patient). All of these five children died 3 to 23 months after the relapse.

Adolescent↗
PubMed1994

MR imaging in the follow-up of malignant and aggressive soft-tissue tumors: results of 511 examinations.

PURPOSE: To present magnetic resonance (MR) imaging findings from 511 follow-up examinations of aggressive soft-tissue tumors. MATERIALS AND METHODS: One hundred eighty-two patients with aggressive soft-tissue tumours underwent postoperative T1- and T2-weighted imaging; 41 also underwent 51 gadolinium-enhanced T1-weighted examinations, and five underwent dynamic gadolinium-enhanced subtraction imaging. RESULTS: Twenty-four of 25 patients (101 of 102 examinations) without high signal intensity (HSI) at T2-weighted imaging had no recurrence. Among 79 patients (321 examinations) who demonstrated HSI without a mass, only two tumors recurred within 1 year. An HSI mass was found in 88 studies of 78 patients and represented recurrence (n = 60), hygroma (n = 24), or a radiation-induced pseudomass (n = 4). Hygromas did not enhance, while recurrences enhanced at 1-3 minutes and postirradiation change enhanced at 4-7 minutes. CONCLUSION: T2-weighted imaging can be used to identify possible recurrence of aggressive soft-tissue tumors, while gadolinium-enhanced imaging can be used to differentiate recurrences from hygromas and inflammatory change.

Adolescent↗
PubMed1994

Apocrine carcinoma: clinical and mammographic features.

PURPOSE: To describe the mammographic features of apocrine carcinoma and assess the patterns of calcifications associated with these lesions. MATERIALS AND METHODS: Clinical and mammographic features from 17 patients with apocrine carcinoma were retrospectively reviewed. Special attention was paid to the presence of mixed form, diffusely scattered microcalcifications on mammograms. RESULTS: Patients were referred for clinical (n = 10), mammographic (n = 2), or both clinical and mammographic (n = 5) abnormalities. Findings at clinical examination included a palpable breast mass (n = 12), multiple breast masses (n = 1), and bloody nipple discharge (n = 2); two patients had normal findings. Fourteen patients had opacities at mammography. These opacities were associated with microcalcifications in 10 cases. Three patients had microcalcifications without opacities; one of those three patients exhibited a mixed form of diffusely scattered calcifications. CONCLUSION: Clinical and mammographic features of apocrine carcinoma do not differ from those of invasive ductal carcinoma.

Adult↗
PubMed1994

Nonpalpable breast tumors: diagnosis with contrast-enhanced subtraction dynamic MR imaging.

PURPOSE: To determine the accuracy of contrast material-enhanced subtraction dynamic magnetic resonance (MR) imaging in the diagnosis of nonpalpable breast tumors. MATERIALS AND METHODS: One hundred forty-three patients underwent surgical biopsy of a nonpalpable breast lesion. Their mammograms showed microcalcifications (n = 80), opacity (n = 52), architectural distortion (n = 10), or asymmetric density (n = 1). All patients underwent a preoperative gadolinium tetraazacyclododecanetetraacetic acid-enhanced subtraction dynamic study. Any early contrast enhancement in the breast parenchyma was considered pathologic. RESULTS: At histologic analysis, 27 intraductal carcinomas, 37 invasive carcinomas, and 79 benign lesions were found. Dynamic MR studies showed early contrast enhancement in 61 of 64 breast cancers (sensitivity, 95%) and in 37 of 79 benign lesions (specificity, 53%). Two invasive lobular carcinomas and one tubular carcinoma showed no early contrast enhancement. CONCLUSION: Subtraction dynamic MR imaging may be helpful to rule out malignancy in nonpalpable breast tumors.

Adult↗
PubMed1994

Locally advanced breast cancer: contrast-enhanced subtraction MR imaging of response to preoperative chemotherapy.

PURPOSE: To determine the value of contrast material-enhanced subtraction magnetic resonance (MR) imaging in assessment of response to chemotherapy in locally advanced breast cancer. MATERIALS AND METHODS: Eighteen women treated with chemotherapy because of locally advanced breast cancer underwent preoperative MR examination including both routine and dynamic MR sequences after injection of gadolinium tetraazacyclododecanetetraacetic acid. Any early contrast enhancement, concomitant with early vascular enhancement during the dynamic MR study, was considered pathologic. RESULTS: Dynamic MR studies showed early contrast enhancement in all women with residual tumor except one with nodular residual tumor. Histopathologic analysis and dynamic MR images of contrast-enhanced lesions correlated well, but in one patient, intraductal extension was not seen on MR images, and in another, additional isolated tumor cells were seen in the histologic specimen. Subtraction images always facilitated visualization of vascular and pathologic contrast enhancement. CONCLUSION: Dynamic MR contrast-enhanced subtraction studies are useful in assessment of residual tumor after chemotherapy.

Adult↗
PubMed1994

Periosteal Ewing sarcoma.

PURPOSE: To evaluate the imaging and histopathologic findings and clinical course of patients with periosteal Ewing sarcoma (PES). MATERIALS AND METHODS: Conventional radiographs, computed tomographic (CT) scans, and magnetic resonance (MR) images in 10 adolescents and one adult were evaluated for the extent and character of PES. RESULTS: Ten of 11 masses were in the proximal extremities and one in the fibula; nine were diaphyseal and two, metadiaphyseal. Radiographs and CT scans showed a subperiosteal mass that did not invade the medullary cavity, was contiguous with and elevated the periosteum, and produced a Codman triangle and periosteal reaction. No PES exhibited osseous or cartilaginous matrix calcifications. MR imaging and histopathologic examination helped confirm the sparing of cancellous bone and the subperiosteal location. CONCLUSION: PES differs from the more common medullary and soft-tissue Ewing sarcomas in location, marked male predominance, and lack of presenting metastases. Except for the absence of matrix calcifications, PES resembles other periosteal sarcomas in imaging characteristics and a less aggressive clinical course.

Adolescent↗