Salvage Percutaneous Cryoablation for Bleeding Upper Tract Urothelial Carcinoma.

PURPOSE: Endoscopic access and treatment of bleeding upper urinary tract urothelial carcinomas (UTUCS) is sometimes difficult and inefficient as resection and/or laser coagulation are often incomplete. We report two cases of successful cryoablation of bleeding UTUCs. MATERIALS AND METHODS: This study evaluated an adjunctive method in using cryoablation as a hemostatic technique. Cryoprobes were inserted inside the affected calices and a standard renal cryoablation protocol was used. Track ablation was performed during the pullback of the cryoprobes to prevent tumor seeding and bleeding. RESULTS: Cryoablation of the bleeding upper urinary tract tumors allowed to efficiently resolve macrohematuria in both patients and to provide prolonged remission in one patient. CONCLUSIONS: Taking advantage of the microcirculatory stasis and the hemostatic properties of cryoablation, we achieved palliative cessation of refractory macrohematuria while sparing nephrons, without the need for renal embolization in patients with bleeding UTUCs.

Image-guided biopsy in primary lung cancer: Why, when and how.

Initial histopathological analysis of a pulmonary lesion is mandatory whenever a lung cancer is suspected in order to determine the optimal diagnostic strategy. Adequate material must be obtained for a definite histological diagnosis (preferable to a cytological one) and in some cases (mainly in adenocarcinoma) molecular analysis. The two main methods to obtain adequate biopsy samples are flexible bronchoscopy and computed tomography (CT)-guided lung biopsy. Flexible bronchoscopy is a valuable method for proximal tumors. On the other hand, CT-guided lung biopsy is more accurate for peripheral tumors. CT-guided lung biopsy is a reliable procedure that conveys a 90% sensitivity for the diagnosis of lung cancer. When performed in a secured environment after contraindications evaluation, its severe complications rate is low, mainly consisting of pneumothorax requiring chest tube placement and hemoptysis.

Diagnostic strategy for the assessment of axillary lymph node status in breast cancer.

The nodal status in breast cancer is a major prognostic factor in terms of survival. It also plays a role in the therapeutic decision-making process. Therefore, the evaluation of lymph node involvement in breast cancer is imperative in establishing a personalized treatment scheme. The sentinel lymph node procedure has proved successful for small breast tumors (T1-T2), limiting axillary lymphadenectomy and its side effects without changing overall survival. Even so, a substantial number of women must undergo axillary lymphadenectomy during a second surgery when the analysis of the sentinel node discloses major nodal involvement. Imaging can improve patient selection, especially those who appear eligible for immediate axillary lymphadenectomy. Ultrasound is able to depict morphological abnormalities in the lymph nodes such as cortical thickening, peripheral vascularization, hilar infiltration and loss of the kidney-shaped appearance of a normal node. When ultrasound is negative, the risk of massive nodal involvement is limited, thus allowing the oncologist to take an approach with the sentinel lymph node procedure. Magnetic resonance imaging (MRI) can also be useful in detecting pathological lymph nodes, particularly with diffusion-weighted MRI sequence.

Biopsies in oncology.

Imaging-guided percutaneous biopsies in patients in oncology provide an accurate diagnosis of malignant tumors. Percutaneous biopsy results are improved by correct use of sampling procedures. The risks of percutaneous biopsy are low and its complications are generally moderate. These risks can be reduced using aids such as blund tip introducers, hydrodissection and correct patient positioning. The multidisciplinary team meetings dialogue between oncologist, surgeon and radiologist correctly defines the indications in order to improve the treatment strategies.

Correlation between MRI and biopsies under second look ultrasound.

The term "second look" lesions in MRI refers to lesions detected by MRI that were not initially seen on mammography or ultrasound. The objectives of our study were to analyse the displacement of targets between MRI and ultrasound; to define discriminating BIRADS morphological criteria to predict benign or malignant character and better establish the indications of second look ultrasound and biopsy; and to analyse the agreement between ultrasound and MRI in terms of morphological criteria. A retrospective and monocentric review was performed of the records of consecutive patients with breast abnormalities (mass or non-mass) initially detected by MRI that were not initially seen on mammography or ultrasound. All patients with abnormalities found during the performance of second look ultrasound and biopsied were included in the study. All lesions were documented using the BIRADS lexicon for MRI and ultrasound. Of 100 included patients, 108 lesions were detected by MRI, found via second look ultrasound and biopsied between January 2008 and 2010. All of the included patients were followed-up for a variable period, from 2 to 5 years. Eighty-two upon 108 biopsied lesions (76%) were benign and 26/108 lesions (24%) were malignant. This study confirmed the switch from procubitus to decubitus essentially displaces the tumour in the antero-posterior direction. It showed that the risk factors were not reliable criteria for establishing an indication for second look ultrasound. This study also showed that circumscribed contours and a progressive enhancement curve (type I) for masses on MRI had the strongest negative predictive value of greater than 0.85. In ultrasound, the round or oval shape, circumscribed contours and the parallel orientation to the skin favoured benignity with a NPV of greater than 0.85. For masses, the study showed that the agreement in interpretation of the benign versus suspicious morphological criteria between the MRI and the ultrasound was very weak for the shape (Kappa=0.09) and weak for the contours (Kappa=0.23). Finally, the MRI overestimated the size of the targets compared to ultrasound (Student t-test, p=0.0001). The performance of second look ultrasound has to be performed after the detection of an abdnormality on MRI even for lesion classified BIRADS 3. The biopsy indications must be wide with insertion of a clip and a control MRI. Only this control allows to stop the investigation if the biopsied lesion is benign.

Perfusion studies in senology.

Microcirculation imaging in breast cancer involves studying tissue enhancement after contrast injection, which is used to calculate perfusion and permeability. The magnitude of enhancement reflects blood and interstitial volumes. This technique has benefitted from advances in MRI, which allow large volumes to be acquired with a good compromise between temporal and spatial resolution. Software has also advanced enabling microcirculation maps to be calculated and heterogeneity to be analyzed. If permeability is increased and interstitial volume is reduced, the microcirculation imaging suggests a suspicious aggressive lesion and can be used for early assessment of neoadjuvant therapies by demonstrating restoration of normal functional indices, which precede morphological changes.

Diagnostic contribution from pulmonary biopsies in hematology patients with acute respiratory failure from undetermined etiology.

BACKGROUND: In about 20% of patients with malignancies with acute respiratory failure (ARF), no etiology can be determined, whatever the diagnostic strategy used. Lung biopsy could then be a precious diagnostic tool leading to therapeutic adaptations and increasing chances for cure. The aim of this study was to assess the diagnostic contribution of lung biopsy in patients for whom a complete diagnosis strategy failed to identify ARF etiology. METHODS: All hematology patients admitted for ARF to our ICU between 1995 and 2011, and for whom lung biopsy was performed were included in the study. Lung biopsies were surgical, CT guided, or post-mortem. Histological findings were compared to prebiopsy diagnosis and classified into specific or non-specific diagnosis. Therapeutic impact (or Goldman-class in post-mortem biopsies) was also recorded. RESULTS: Among the 1440 hematology patients with ARF managed during the study period, 21 (1%) biopsies were performed, including 10 post-mortem biopsies. Histological diagnoses were specific in 10 biopsies, non specific in 8 biopsies and lung parenchyma was normal in three patients. In 8/11 (72.7%) alive patients, lung biopsy had lead to therapeutic modifications, including treatment implementation in 5 patients and treatment withdrawal in 3 patients. One out of 10 (10%) patients had minor complications. For the 10 dead patients, only one Goldman-type 1 error was found. CONCLUSION: Diagnostic lung biopsy is rarely needed in hematology patients with ARF. But, it has a 73% therapeutic impact and has overall no major complications. Contribution from post-mortem biopsies seems less relevant.

CT-guided biopsies in lung infections in patients with haematological malignancies.

CT-guided transparietal lung biopsy in imaging makes it possible to find the pathogenic agent in half of all fungal infections and most bacterial infections (sensitivity=55%, specificity=100%). Performance is decreased in consolidations (50% of infections) compared to masses. Complications, pneumothorax, alveolar bleeding and hemoptysis are generally benign and rarely (<5%) require specific treatment. On the other hand, the diagnostic performance increases significantly with the calibre of 18G co-axial systems compared to 20G. The risk is not related to the number of samples or platelet levels.

Diffusion-weighted MR imaging of the breast: advantages and pitfalls.

The aim of this paper is to review all clinical applications of diffusion weighted MR imaging (DWI) for breast pathology. The challenge of DWI is to obtain the best compromise between lesion detection and characterization. Technical factors affecting lesion characterization and detection are detailed including the effect of contrast administration, the choice of number of b and of b(max), the variation of diagnostic performance according to the type and the size of lesion studied.

Image-guided needle biopsy for diagnosis and molecular biology in lymphomas.

Core needle biopsy is increasingly replacing excisional lymph node biopsy in the diagnosis and subclassification of malignant lymphomas, with obvious advantages in terms of morbidity and costs. This technique has radically altered the diagnostic strategy of enlarged lymph nodes at our institution, avoiding unnecessary nodal excisions. It represents a viable alternative as long as the number and size of cores for morphologic and molecular studies are not compromised. This quick and safe technique can be applied to the initial diagnostic evaluation of malignant lymphomas as well as the reassessment of previously diagnosed malignant lymphomas at time of progression or recurrence.

Breast inflammation: indications for MRI and PET-CT.

Breast MRI should not be used for differential diagnosis between inflammatory breast cancer and acute mastitis (AM) prior to treatment. When mastitis symptoms persist after 10 to 15 days of well-managed medical treatment, MRI may be performed in addition to an ultrasound examination, a mammogram and to taking histological samples, in order to eliminate inflammatory breast cancer (IBC). For staging, MRI would seem to be useful in looking for a contralateral lesion, PET-CT for finding information about remote metastases and in certain centres, for information about the initial extension to local/regional lymph nodes, which would guide the fields of irradiation (since patients can become lymph node negative after neoadjuvant chemotherapy). MRI and PET-CT seems to be useful for early detection of patients responding poorly to neoadjuvant chemotherapy so that the latter may be rapidly modified.

BI-RADS categorisation of 2,708 consecutive nonpalpable breast lesions in patients referred to a dedicated breast care unit.

OBJECTIVES: To determine the malignancy rate of nonpalpable breast lesions, categorised according to the Breast Imaging Reporting and Data System (BI-RADS) classification in the setting of a Breast Care Unit. METHODS: All nonpalpable breast lesions from consecutive patients referred to a dedicated Breast Care Unit were prospectively reviewed and classified into 5 BI-RADS assessment categories (0, 2, 3, 4, and 5). RESULTS: A total of 2708 lesions were diagnosed by mammography (71.6%), ultrasound (8.7%), mammography and ultrasound (19.5%), or MRI (0.2%). The distribution of the lesions by BI-RADS category was: 152 in category 0 (5.6%), 56 in category 2 (2.1%), 742 in category 3 (27.4%), 1523 in category 4 (56.2%) and 235 in category 5 (8.7%). Histology revealed 570 malignant lesions (32.9%), 152 high-risk lesions (8.8%), and 1010 benign lesions (58.3%). Malignancy was detected in 17 (2.3%) category 3 lesions, 364 (23.9%) category 4 lesions and 185 (78.7%) category 5 lesions. Median follow-up was 36.9 months. CONCLUSION: This pragmatic study reflects the assessment and management of breast impalpable abnormalities referred for care to a specialized Breast Unit. Multidisciplinary evaluation with BI-RADS classification accurately predicts malignancy, and reflects the quality of management. This assessment should be encouraged in community practice appraisal.

[CT-guided percutaneous biopsies]. / Biopsies percutanées sous scanner.

The number of biopsy requests continuously increases over the years. Similarly, lesions that are not amenable to CT-guided biopsy are exceptional due to improved imaging guidance and technical advances. The needle tract should preferably go through fat, which is less painful and safer. The biopsy should be painless with the use of local anesthetics complemented by intravenous sedation. Blunt introducers and hydrodissection techniques create access to lesions without injury to vessels, bowel loops and fascias. The biopsy samples should be processed in accordance with the suspected diagnosis.

Immunohistochemical and molecular analyses of HER2 status in breast cancers are highly concordant and complementary approaches.

BACKGROUND: Immunohistochemistry (IHC) and fluorescent in situ hybridisation (FISH) are currently the most commonly used methods to assess HER2 status. PCR-based assays allow quantitative determination of HER2 amplification (Q-PCR) or overexpression (Q-RT-PCR), but are not routinely used. We evaluated the relevance of Q-RT-PCR for HER2 status determination. METHODS: We compared IHC and Q-RT-PCR in 466 breast tumours. In discordant or equivocal cases, five additional methods (IHC with two other antibodies, FISH, silver in situ hybridisation (SISH) and Q-PCR) were combined to determine HER2 status. Two cases with HER2 intra-tumour heterogeneity were further explored by allelic profiles analysis and HUMARA clonality determination after microdissection. RESULTS: We observed 97.3% concordance between Q-RT-PCR and non-equivocal IHC. Twelve out of 466 cases (3%) revealed discordances between the two methods. The power of Q-RT-PCR to predict HER2 status (defined by seven methods) was similar to that of IHC. Although rare, some discordances between techniques might be due to HER2 intra-tumour heterogeneity and we report two examples, one tumour containing two distinct clones, another tumour consisting of HER2 amplified and non-amplified subclones. CONCLUSION: Q-RT-PCR and IHC are highly concordant methods for HER2 status assessment, and Q-RT-PCR allows a highly reliable quantitative assessment and could be a useful adjunct to IHC.

[Diffusion-weighted MR imaging of the breast]. / Diffusion en IRM mammaire.

Diffusion-weighted imaging is helpful to further characterize lesions that remain indeterminate after morphological and dynamic MR evaluation. Suspicious lesions are hyperintense on diffusion-weighted images with corresponding low ADC values, indicating restricted diffusion and hypercellularity. Benign lesions and tumors responding to treatment usually have no diffusion restriction. ADC maps are useful for T2W hyperintense lesions that could mask the presence of restricted diffusion. Image fusion is sometimes needed to accurately localize enhancing lesions on ADC maps. For indeterminate lesions, a hypocellular appearance suggests a lower ACR category whereas the presence of restricted diffusion suggests a higher category.

[CT and MRI imaging in tumoral angiogenesis]. / Imagerie TDM et IRM de l'angiogenèse tumorale.

Angiogenesis is the process of activating dormant endothelial cells to form new vessels, after stimulation and it is essential in tumor growth. In many types of cancer, angiogenesis results from the activation of oncogenes that stimulate the production of Vascular Endothelial Growth Factor (VEGF). However, these newly formed vessels have a great number of abnormalities: increased density of fragile and hyper-permeable microvessels, arterial-venous shunts, caliber abnormalities and flow instabilities susceptible to flow direction inversion according to interstitial pressure. Anti-angiogenic treatments inhibit VEGF activity, perceived as structural and functional normalization of the microvascular pattern, such as reduced density of microvessels and restored morphology of the remaining ones. Conventional imaging techniques are not sensible to these changes, at best they show tumor size stabilization, hence the need of new techniques. Microvascularization imaging can be achieved by detecting functional disturbances to blood flow and not by showing the microvasculature per se. These techniques are based in quantifying the enhancement in tumor due to the passage of contrast agent after injection or protons labeled by a magnetic field. Through these measurements, one can derive interstitial and blood volumes as well as the tissue perfusion and capillary wall permeability. Microvascular imaging has greatly benefited from the improvements seen in CT and MRI equipment allowing large volume coverage with high spatial and temporal resolutions as from the evolutions in the methods to calculate, present and compare maps of the microcirculation and it's heterogeneity. However, software to analyze microvascularization are still rare, limiting the technique's application and validation in large scale. Nevertheless, imaging of the microcirculation is useful throughout the care of the oncological patient: it can reinforce the suspicious nature of a lesion, suggest anti-angiogenic treatment efficacy in hypervascular lesions, and show early treatment response before morphological changes as in RECIST criteria.

[Imaging and PET-CT of adult and childhood lymphoma]. / Imagerie radiologique et TEP scanner des lymphomes de l'adulte et de l'enfant.

Malignant lymphomas are lymphoproliferative disorders arising in both lymphoid tissue and non-lymphoid organ systems. Treatment rarely is surgical, and currently relies on a combination of chemotherapy and radiation therapy. The role of imaging is to determine the spread of the disease, to identify targets and to assess therapeutic response. Imaging techniques mainly use morphological criteria, and may underestimate infiltrative disease, as observed in bones. The frequent presence of residual masses after treatment usually prevents classification of patients as complete response. Over time, positron emission tomography (PET) with F18-fluorodeoxyglucose (FDG) has become a prominent part of the workup at diagnosis and during follow-up. Recently, PET has been integrated in the revised response criteria for malignant lymphoma.

Reduced capillary perfusion and permeability in human tumour xenografts treated with the VEGF signalling inhibitor ZD4190: an in vivo assessment using dynamic MR imaging and macromolecular contrast media.

We describe the use of perfusion-permeability magnetic resonance imaging (ppMRI) to study hemodynamic parameters in human prostate tumor xenografts, following treatment with the vascular endothelial growth factor-A (VEGF) receptor tyrosine kinase inhibitor, ZD4190. Using a macromolecular contrast agent (P792), a fast MR imaging protocol and a compartmental data analysis, we were able to demonstrate a significant simultaneous reduction in tumor vascular permeability, tumor vascular volume and tumor blood flow (43%, 30% and 42%, respectively) following ZD4190 treatment (100 mg/kg orally, 24 h and 2 h prior to imaging). This study indicates that MR imaging can be used to measure multiple hemodynamic parameters in tumors, and that tumor vascular permeability, volume and flow, can change in response to acute treatment with a VEGF signaling inhibitor.