Computer-aided-detection marker value and breast density in the detection of invasive lobular carcinoma

Purpose

Invasive Lobular Carcinoma (ILC) is frequently a mammographic and diagnostic dilemma; thus any additional information that CAD (Computer-Aided Detection) systems can give radiologists may be helpful. Our study was to evaluate the role of CAD numeric values as indicators of malignancy and the effect of breast density in the diagnosis of ILC.

Materials and methods

Eighty consecutive biopsy-proven ILC cases with CAD (ImageChecker^®, Hologic | R2, Santa Clara, CA, versions 2.3, 3.1, 3.2, 5.0, 5.2) diagnosed between June 2002 and December 2004 were retrospectively reviewed. Data included: BIRADS^® breast density, whether CAD marked the cancer at diagnosis year or years prior, and lesion type. Study mammograms underwent additional CAD scans (Image Checker^® V5.3, V8.0, V8.1) to obtain a numeric value associated with each marker, low values represent increasingly suspicious features.

Results

CAD correctly marked 65% (52/80) of ILC cases, detection was found to decrease with increased breast density. Numeric values of CAD marks at sites of carcinoma showed median score of 171 (range 0 – 1121).

Conclusion

The CAD marker may potentially be used as an additional indicator of suspicious lesion features in all breast densities and higher likelihood that an area on the mammogram requires further investigation.     

Computer-aided detection of breast carcinoma in standard mammographic projections with digital mammography

Purpose

A retrospective evaluation of the ability of computer-aided detection (CAD) ability to identify breast carcinoma in standard mammographic projections.

Materials and methods

Forty-five biopsy proven lesions in 44 patients imaged digitally with CAD applied at examination were reviewed. Forty-four screening BIRADS^® category 1 digital mammography examinations were randomly identified to serve as a comparative normal/control population. Data included patient age; BIRADS^® breast density; lesion type, size, and visibility; number, type, and location of CAD marks per image; CAD ability to mark lesions; needle core and surgical pathologic correlation.

Results

The CAD lesion/case sensitivity of 87% (n = 39), image sensitivity of 69% (n = 31) for mediolateral oblique view and 78% (n = 35) for the craniocaudal view was found. The average false positive rate in 44 normal screening cases was 2.0 (range 1–8). The 2.0 figure is based on 88 reported false positive CAD marks in 44 normal screening exams: 98% (n = 44) lesions proceeded to excision; initial pathology upgraded at surgical excision from in situ to invasive disease in 24% (n = 9) lesions.

Conclusion

CAD demonstrated potential to detect mammographically visible cancers in standard projections for all lesion types.     

Incidentally detected cystic lesions of the pancreas on CT: review of literature and management suggestions

Purpose

To facilitate a better understanding of incidentally noted cystic pancreatic lesions, since these lesions often pose a challenge regarding appropriate management.

Methods

This article reviews pathophysiology, prevalence, significance, and recommendations for management of the various pancreatic cystic lesions. Illustrative cases are demonstrated.

Results

Diagnostic benign lesions can be left alone. Cross-sectional imaging can be used to follow-up benign appearing lesions and to stage more aggressive ones. Endoscopic ultrasound with fine needle aspiration and cyst fluid analysis can be performed on certain indeterminate lesions. Lesions with high malignant potential should undergo resection.

Conclusions

A better understanding of the variety of incidentally detected pancreatic cystic lesions can help direct appropriate management.     

Importance of operator training and rest perfusion on the diagnostic accuracy of stress perfusion cardiovascular magnetic resonance

Background

Clinical evaluation of stress perfusion cardiovascular magnetic resonance (CMR) is currently based on visual assessment and has shown high diagnostic accuracy in previous clinical trials, when performed by expert readers or core laboratories. However, these results may not be generalizable to clinical practice, particularly when less experienced readers are concerned. Other factors, such as the level of training, the extent of ischemia, and image quality could affect the diagnostic accuracy. Moreover, the role of rest images has not been clarified.The aim of this study was to assess the diagnostic accuracy of visual assessment for operators with different levels of training and the additional value of rest perfusion imaging, and to compare visual assessment and automated quantitative analysis in the assessment of coronary artery disease (CAD).

Methods

We evaluated 53 patients with known or suspected CAD referred for stress-perfusion CMR. Nine operators (equally divided in 3 levels of competency) blindly reviewed each case twice with a 2-week interval, in a randomised order, with and without rest images. Semi-automated Fermi deconvolution was used for quantitative analysis and estimation of myocardial perfusion reserve as the ratio of stress to rest perfusion estimates.

Results

Level-3 operators correctly identified significant CAD in 83.6% of the cases. This percentage dropped to 65.7% for Level-2 operators and to 55.7% for Level-1 operators (p?<?0.001). Quantitative analysis correctly identified CAD in 86.3% of the cases and was non-inferior to expert readers (p?=?0.56). When rest images were available, a significantly higher level of confidence was reported (p?=?0.022), but no significant differences in diagnostic accuracy were measured (p?=?0.34).

Conclusions

Our study demonstrates that the level of training is the main determinant of the diagnostic accuracy in the identification of CAD. Level-3 operators performed at levels comparable with the results from clinical trials. Rest images did not significantly improve diagnostic accuracy, but contributed to higher confidence in the results. Automated quantitative analysis performed similarly to level-3 operators. This is of increasing relevance as recent technical advances in image reconstruction and analysis techniques are likely to permit the clinical translation of robust and fully automated quantitative analysis into routine clinical practice.

     

Epidermoid cyst in intrapancreatic accessory spleen: computed tomography findings and clinical manifestation

Objective

This study aims to assess retrospectively the imaging features of computed tomography (CT) and clinical characteristics of epidermoid cyst in intrapancreatic accessory spleen (ECIPAS).

Methods

Seven consecutive patients with pathologically confirmed ECIPAS were included. CT images and clinical data were analyzed. The CT features emphasized included the location, size, calcification, cystic features, surrounding accessory spleen, density, and enhancement of the lesions.

Results

Five patients were male and two were female with a mean age of 43.2?years ranging from 25 to 66?years. Most cases were incidentally detected. All lesions were situated in the pancreatic tail, wherein the mean size was 4.4?cm. The cyst appeared unilocular in four cases and multilocular in three cases. An accessory spleen surrounding the cyst was recognized in all seven cases, and the cystic wall of ECIPAS showed a contrast enhancement similar to that of the spleen during multiphasic scans.

Conclusion

ECIPAS is an extremely rare entity. The diagnosis of an ECIPAS should be considered when enhancing the cystic wall of the lesion in the pancreatic tail similar to that of the spleen during multiphasic scans.     

Verification of recall criteria for masses detected on ultrasound breast cancer screening

Purpose

Mammography is the only modality for breast cancer screening demonstrated to reduce the mortality rate. However, ultrasonographic screening is already being widely performed as opportunistic screening in Japan. The recall criteria for masses are very important as quality controls. The purpose of this study was to verify these criteria at multiple institutions.

Methods

Screening was performed by five institutions in various regions in Japan. The total number of cases screened at all five institutions was 10,519.

Results

The findings that could be concluded to be benign were a cystic pattern and three features of a solid pattern. The cystic pattern was noted in 6512 cases, typical fibroadenoma in 1483 cases, and typical complicated cyst in 70 cases. Only three of these 8065 cases were cancers, so the negative predictive value was 99.9%. The solid pattern with obvious malignant features, i.e., masses with an echogenic halo and/or interruption of the interface and masses with multiple echogenic foci, were noted in 33 cases. Twenty of the 33 cases were malignancy, resulting in a positive predictive value of 66.7%.

Conclusion

Although some parts of the criteria should be considered further for verification and revision, the current recall criteria are mostly valid.

     

Volumetric texture features from higher-order images for diagnosis of colon lesions via CT colonography

Purpose

Differentiation of colon lesions according to underlying pathology, e.g., neoplastic and non-neoplastic lesions, is of fundamental importance for patient management. Image intensity-based textural features have been recognized as useful biomarker for the differentiation task. In this paper, we introduce texture features from higher-order images, i.e., gradient and curvature images, beyond the intensity image, for that task.

Methods

Based on the Haralick texture analysis method, we introduce a virtual pathological model to explore the utility of texture features from high-order differentiations, i.e., gradient and curvature, of the image intensity distribution. The texture features were validated on a database consisting of 148 colon lesions, of which 35 are non-neoplastic lesions, using the support vector machine classifier and the merit of area under the curve (AUC) of the receiver operating characteristics.

Results

The AUC of classification was improved from 0.74 (using the image intensity alone) to 0.85 (by also considering the gradient and curvature images) in differentiating the neoplastic lesions from non-neoplastic ones, e.g., hyperplastic polyps from tubular adenomas, tubulovillous adenomas and adenocarcinomas.

Conclusions

The experimental results demonstrated that texture features from higher-order images can significantly improve the classification accuracy in pathological differentiation of colorectal lesions. The gain in differentiation capability shall increase the potential of computed tomography colonography for colorectal cancer screening by not only detecting polyps but also classifying them for optimal polyp management for the best outcome in personalized medicine.     

Treatment With Chemotherapy and Cognitive Functioning in Older Adult Cancer Survivors

Objective

To investigate whether treatment of cancer with chemotherapy, as compared with surgery and radiation, differentially affects cognitive functioning in older adults.

Computed tomography features of gastrointestinal linitis plastica: spectrum of findings in early and delayed phase imaging

Purpose

To analyze the features of gastrointestinal linitis plastica obtained by computed tomography (CT).

Materials and methods

We conducted a single-center, retrospective analysis of 45 cases of gastrointestinal tract linitis plastica collected over a 10-year period. “Linitis plastica” was defined based on histological characteristics. Primary and secondary linitis plastica were included. Two readers independently assessed the radiological findings (i.e., number of lesions, mass, wall thickening, and enhancement).

Results

The patient cohort comprised 23 men and 22 women with an average age of 63.2 years. The main presenting signs and symptoms were impaired general health and ascites (22/45 patients, 48.8%). The stomach was the affected organ in 68.3% of the cases, while the rectum was affected in 11.7% of the cases. Primary linitis was found in 73.3% of the cases, and solitary lesions were found in 77.8% of the cases. The most common CT finding was wall thickening (91.7%) with a complete disappearance of folds and enhancement of the entire wall at 2 min. Four lesions (6.6%) were described as masses, and only one (1.7%) was described as a wall atrophy.

Conclusion

Linitis plastica can affect the entire digestive system. Its potentially secondary nature necessitates a systematic search for a primary tumor. An appropriate CT protocol is required to detect the specific radiological features of this fibrous cancer. CT can help confirm the diagnosis of linitis plastica, rule out differential diagnoses, and indicate the need for deep biopsies where possible.

     

CT findings of primary clear cell carcinoma of liver: with analysis of 19 cases and review of the literature

Purpose

To analyze CT characteristics of primary clear cell carcinoma of the liver (PCCCL) and improve the current understanding and diagnose accuracy of the tumor.

Methods

Pre- and post-contrast CT images of 19 patients with pathology proven PCCCL were retrospectively analyzed. The clinical data and CT findings as well as relevant literature reports were reviewed.

Results

Thirteen patients were tested positive for HBsAg, and two patients were positive for HCVAb. The serum alpha-fetoprotein (AFP) levels of most tumors (14/19) were ≤20 ng/ml with 14 cases were associated with liver cirrhosis. All lesions were solitary intraparenchymal mass lesions which have well-defined boarders. On pre-contrast CT scans, 15 lesions appeared as hypo-attenuation and four lesions appeared as isointensity to the adjacent liver parenchyma. On post-contrast CT scans, 16 lesions showed avid enhancement on the hepatic arterial phase, of which 6 lesions were hypo-attenuation, and 10 lesions remained slightly hyper-attenuation or iso-attenuation on the portal venous phase images. Three lesions showed only mild enhancement on the hepatic arterial phase and hypo-attenuation on the portal venous phase. All lesions demonstrated hypointensity on the equilibrium phase. There are 12 lesions showed pseudocapsules. None of patients showed signs of portal vein thrombosis. There was no distal metastasis except only one patient had lymph node metastasis.

Conclusion

The characteristics of CT imaging of PCCCL, such as tend to form pseudocapsules and less involved with vascular invasion, could be useful in differentiating from common type hepatocellular carcinoma (CHCC). Some CT imaging characteristics of PCCCL are similar to CHCC, such as prone to occur in patients with liver cirrhosis and early enhancement pattern on the hepatic arterial phase as well as hypo-attenuation on the equilibrium phase. Those features could be useful in differentiating PCCCL from other liver tumors, such as hemangioma and hepatic metastases.     

A Novel Fluorescent Imaging Agent for Diffuse Optical Tomography of the Breast: First Clinical Experience in Patients

Purpose

This is the first clinical evaluation of a novel fluorescent imaging agent (Omocianine) for breast cancer detection with diffuse optical tomography (DOT).

Procedures

Eleven women suspected of breast cancer were imaged with DOT at multiple time points (up to 24 h) after receiving an intravenous injection of Omocianine (doses 0.01 to 0.1 mg/kg bodyweight). Breast MRI was obtained for comparison.

Results

Histopathology showed invasive cancer in ten patients and fibroadenoma in one patient. With the lowest dose of Omocianine, two of three lesions were detected; with the second dose, three of three lesions were detected; with the two highest doses, none of five lesions were detected. Lesion location on DOT showed excellent agreement with MRI. Optimal lesion-to-background signals were obtained after 8 h. No adverse events occurred.

Conclusions

Lowest doses of Omocianine performed best in lesion detection; DOT using a low-dose fluorescent agent is feasible and safe for breast cancer visualization in patients.     

Generating prostate models by means of geometric deformation with application to computerized training of cryosurgery

Purpose

As a part of an ongoing project to develop computerized training tools for cryosurgery, the objective of the current study is twofold: to compile literature data on the likelihood of cancer tumor growth and its effect on the prostate shape and to present a deformation scheme for a 3D organ template in order to generate clinically relevant prostate models. The long-term objective of this study is to develop a database of prostate models for computerized training.

Methods

Cryosurgery is typically performed on patients with localized prostate cancer found in stage T3 or earlier. The distribution of key geometric features likely to be found in the prostate at stage T3 is integrated into a 3D prostate template by employing the extended free-form deformation (EFFD) method. The applied scheme combines two steps: pre-selecting a set of geometric parameter values and manipulating the lattice control points until the prostate model meets the desired criteria.

Results

Examples for model generation are displayed, based on two 3D prostate templates previously obtained from ultrasound imaging. These examples include selected cases with unilateral and bilateral stage T3 tumor growth, suitable for incorporation into a training database.

Conclusions

EFFD is an efficient method for rapid generation of prostate models. The compiled criteria for model generation do not lead to a unique shape since the contours for template deformation are randomly selected. Nevertheless, these criteria do lead to shapes resembling cancer growth, as various growth histories can lead to a tumor characterized by the same key parameter values.     

Pseudomyxoma peritonei: some different sonographic findings

Objectives

The purpose of our study was to assess the sonographic features of pseudomyxoma peritonei (PMP).

Materials and methods

All records of peritoneal biopsies under the guidance of ultrasound in our institutional database from April 2007 to June 2011 were retrospectively reviewed. 19 cases of PMP and 279 cases of other peritoneal lesions were included in the study. The sonograms of peritoneum, ascites, and parenchymal organs involved by PMP were evaluated, respectively, and compared with sonograms of other peritoneal lesions.

Results

Anechoic areas were found in 89.5% cases of PMP at high frequency of insonation and the sensitivity in indicating PMP was 100%. In the pelvic cavity, echogenic foci in ascites of PMP in 52.6% cases were mobile. The specificity of “starburst” appearance and sensitivity of scalloping of the liver margin were relatively high (82.3 and 88.1%), but the sensitivity and specificity (57.9 and 42.1%) of these two signs were relatively low.

Conclusion

Anechoic area in the thickened peritoneum was a specific sign in indicating the diagnosis of PMP and high-frequency transducer could reveal these tiny anechoic areas more explicitly. In the pelvic cavity, echogenic foci in ascites of PMP could be observed to be mobile and scalloping of the liver margin and “starburst” appearance also played a significant role in indicating PMP.     

Transcatheter aortic valve implantation in patients with and without concomitant coronary artery disease: comparison of characteristics and early outcome in the German multicenter TAVI registry

Objective

To examine the prevalence and impact of concomitant coronary artery disease (CAD) on short-term outcome after transcatheter aortic valve implantation (TAVI).

Background

The prevalence of CAD in patients undergoing surgical aortic valve replacement is estimated at 30–50?% and its presence increases procedural risk. The prevalence and impact of CAD on outcome after TAVI are not well defined.

Methods

We analyzed 1,382 patients enrolled in the German TAVI registry; the majority (81?%) received the Medtronic CoreValve. The presence of coronary lesions with ≥50?% stenosis on pre-TAVI angiography defined the existence of concomitant CAD.

Results

859 patients (62.2?%) had concomitant CAD, of which 534 (62.3?%) had multi-vessel and 83 (9.7?%) left main disease. Patients with CAD were younger (81.5?±?6.1 vs. 82.1?±?6.3?years, p?<?0.05), more commonly males (49.4 vs. 30.0?%, p?<?0.0001) and diabetics (36.9 vs. 31.2?%, p?<?0.05), and had a worse Canadian Cardiovascular Society angina class at baseline compared to patients with no CAD. During TAVI patients with CAD more often required additional coronary intervention and had longer procedures, but procedural success rates were similar (97.1 vs. 97.7?%). Crude in-hospital mortality was higher in patients with CAD (10.0 vs. 5.5?%, OR 1.90, 95?% CI 1.23–2.93), but this was not significant after adjustment for confounders (adjusted OR 1.41, 95?% CI 0.85–2.33). Both groups had significant improvement in 30-day symptoms and quality of life.

Conclusion

The prevalence of CAD in contemporary TAVI patients is high. Its presence characterizes a high-risk population and is associated with increased crude short-term mortality, largely explained by co-morbidities, but does not limit functional improvement after TAVI.     

Differential diagnosis of solid pancreatic lesions using contrast-enhanced three-dimensional ultrasonography

Purpose

To investigate the usefulness of contrast-enhanced three-dimensional ultrasonography (CE 3D US) for differential diagnosis of solid pancreatic lesions.

Methods

Eighty-five patients with solid pancreatic lesions who underwent CE 3D US were retrospectively analyzed. Sixty-four patients had pancreatic ductal adenocarcinoma (PDAC), 10 had mass-forming pancreatitis (MFP), and 11 had neuroendocrine tumor (NET). Two blinded readers evaluated the enhancement patterns using four features: vascularity in the arterial phase, vascularity in the venous phase, vessel location, and vessel form. Vascularity in both phases was classified as hypervascular, isovascular, or hypovascular. Vessel location was classified into peritumoral or intratumoral. Vessel form was classified into fine or irregular. Kappa values were used to assess inter-reader agreement. The institutional review board approved this study, and informed consent was obtained.

Results

Kappa values of the four features were 0.75, 0.72, 0.85, and 0.65, which were graded as good or excellent. The most typical combined enhancement pattern in PDAC was hypovascularity in both phases with peritumoral and irregular vessels; MFP was isovascular in both phases with intratumoral and fine vessels; and NETs were hypervascular in both phases with intratumoral and irregular vessels. The sensitivity and positive predictive value of the three patterns were 93.8% and 96.7% for the PDAC pattern, 80.0% and 100% for the MFP pattern, and 81.8%, and 69.2% for the NET pattern, respectively. The accuracy of these diagnostic criteria was 90.5%.

Conclusion

CE 3D US allows detailed visualization of the enhancement patterns of various pancreatic lesions and can be used for the differential diagnosis.     

Evaluation of novice reader diagnostic performance in coronary CT angiography using an advanced cardiac software package

Purpose

The purpose of this research was to evaluate whether a commercially available advanced cardiac software package for coronary CT angiography (CTA) interpretation may reliably assist inexperienced readers to screen for significant coronary artery stenoses.

Methods

Coronary CTA data sets of 61 consecutive patients with suspected coronary artery disease were evaluated by three novice readers with no experience in cardiac CT interpretation. In the first 15 patients, the novice readers were trained to use the advanced cardiac software package (includes automatic detection of coronary vessels, curved MPR and VRT reconstructions and a measurement too) knowing the results of an expert read. In the next 46 patients, the novice readers had to state whether there is a significant coronary artery stenosis ( \(>\) 50 %) and if they are confident with their diagnosis. The results of the novice readers were compared to the expert read.

Results

The 46 coronary CTA data sets contained 184 vessels with 15 stenoses in 9 patients. On a per-vessel analysis, novice reader 1/2/3 demonstrated 60 %/100 %/ 93% sensitivity, and 98 %/90 %/86 % specificity. Per patient, the readers diagnosed 36/28/29 cases correctly as free of stenoses, 6/9/8 correctly as having at least one stenosis, missed 3/0/1 cases with a stenosis and overdiagnosed 1/9/8 patients. Cohen’s kappa values for the three readers versus the expert were 0.60, 0.61 and 0.54. The three novice readers felt confident in the diagnosis of 36/33/30 patients. In these patients, they missed one significant stenosis, showed a sensitivity of 100 %/100 %/75 % and a specificity of 100 %/92 %/88 %.

Conclusions

The evaluated advanced cardiac software package successfully assists novice readers in interpreting coronary CTA data sets especially in ruling out significant coronary artery stenosis.     

Evaluation of whether the ultrasonographic onion skin sign is specific for the diagnosis of an appendiceal mucocele

Purpose

To evaluate whether the onion skin sign on ultrasonography (US) of the lower abdomen is specific for the diagnosis of an appendiceal mucocele.

Methods

Our study included 231 lesions from 229 patients in whom transabdominal US detected lesions in the lower abdomen and who had definitive pathological diagnoses in the small bowel, ileocecal valve, cecum, appendix, mesentery, adnexa uteri or pelvic cavity outside the major organs. Patients with metastatic tumors were excluded. We reviewed the reports and images from transabdominal US and checked for the presence of the onion skin sign. The sensitivity, specificity, and accuracy of the sign for the diagnosis of an appendiceal mucocele were calculated.

Results

Five (2.2 %) of the 231 lesions showed the onion skin sign on US and all were diagnosed with an appendiceal mucocele. The sensitivity, specificity, and accuracy of the sign for the diagnosis of an appendiceal mucocele were 63, 100, and 99 %, respectively.

Conclusions

The onion skin sign in the lower abdomen appears to be specific for the diagnosis of an appendiceal mucocele. In cases where the onion skin sign is obviously present in the lower abdomen on US, an appendiceal mucocele should be considered as the leading diagnosis.     

Selecting relevant 3D image features of margin sharpness and texture for lung nodule retrieval

Purpose

Lung cancer is the leading cause of cancer-related deaths in the world. Its diagnosis is a challenge task to specialists due to several aspects on the classification of lung nodules. Therefore, it is important to integrate content-based image retrieval methods on the lung nodule classification process, since they are capable of retrieving similar cases from databases that were previously diagnosed. However, this mechanism depends on extracting relevant image features in order to obtain high efficiency. The goal of this paper is to perform the selection of 3D image features of margin sharpness and texture that can be relevant on the retrieval of similar cancerous and benign lung nodules.

Methods

A total of 48 3D image attributes were extracted from the nodule volume. Border sharpness features were extracted from perpendicular lines drawn over the lesion boundary. Second-order texture features were extracted from a cooccurrence matrix. Relevant features were selected by a correlation-based method and a statistical significance analysis. Retrieval performance was assessed according to the nodule’s potential malignancy on the 10 most similar cases and by the parameters of precision and recall.

Results

Statistical significant features reduced retrieval performance. Correlation-based method selected 2 margin sharpness attributes and 6 texture attributes and obtained higher precision compared to all 48 extracted features on similar nodule retrieval.

Conclusion

Feature space dimensionality reduction of 83 % obtained higher retrieval performance and presented to be a computationaly low cost method of retrieving similar nodules for the diagnosis of lung cancer.

     

Thrombosis, cancer and renal insufficiency: low molecular weight heparin at the crossroads

Background

Venous thromboembolism (VTE) and renal insufficiency are common in cancer patients. Prompt treatment is necessary to reduce the high rates of VTE-related mortality and morbidity. VTE prophylaxis is underused in cancer patients. We review current recommendations for the treatment and prevention of VTE in cancer patients and discuss low molecular weight heparin (LMWH) use in cases of renal failure.

Design

This study is a retrospective literature review.

Results

There are few published recommendations for LMWH use in cancer patients with renal insufficiency. Treatment guidelines largely follow recommendations for other patients with renal failure. Enoxaparin therapy is complicated by the need for regular monitoring of renal function and anti-Xa levels and for dosage adjustment to prevent bleeding. Few data are available to support the systematic use of dalteparin. Tinzaparin is least likely to bioaccumulate in patients with renal failure.

Conclusion

VTE is the second most common cause of death in cancer patients. Renal insufficiency is present in 50–60?% of cancer patients. Data from renal patients suggest that tinzaparin may be safe and effective for VTE treatment and prevention in cancer patients with renal failure.