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Publications (6)23.62 Total impact

  • Article: Diagnostic yield of percutaneous image‐guided tissue biopsy of focal hepatic lesions in cancer patients
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    ABSTRACT: BACKGROUND:The diagnostic yield was evaluated of percutaneous image-guided tissue biopsy of hepatic lesions identified on computed tomography performed for staging of a primary malignancy, and it was determined how often the biopsy result was unexpectedly negative, benign, or secondary to a second unknown malignancy.METHODS:In a retrospective investigation from 1998 through 2008, 580 patients with primary malignancies had indeterminate focal hepatic lesions and underwent percutaneous image-guided biopsy; 369 patients had lesions in their liver at first cross-sectional imaging, performed for staging; 211 patients had a negative liver imaging study, followed by the subsequent appearance of at least 1 indeterminate suspicious lesion. The results of percutaneous image-guided tissue biopsies were compared with the histology of the primary malignancy.RESULTS:Liver biopsies were performed in 580 patients (288 men and 292 women; age, 25-92 years; mean age, 61 years). The most common primary malignancies were pancreatic (n = 96), breast (n = 85), melanoma (n = 57), esophageal (n = 51), lung (n = 47), colorectal (n = 37), and urothelial tumors (n = 26). Biopsy results were positive for malignancy in 528 (91%) cases. Among the positive biopsies, 29 (5%) cases had pathology results different from the primary tumor. Of the 52 biopsies negative for malignancy, 20 yielded a specific benign diagnosis, and 32 were nondiagnostic.CONCLUSIONS:If all liver lesions had been assumed to be metastases, as expected secondary to the known primary tumor, then the true or presumed alternate diagnosis would have been missed in 60 (10.3%) of the 580 cases. The authors did not attempt to determine whether actual clinical management changed based on these 60 liver biopsy results, so this number is an upper bound on management change. On the basis of these results, and given the minimal complication rate of liver biopsy, the authors suggest that liver biopsy should still be performed in the types of cases studied here, despite the finding that the vast majority of biopsies produced the expected result and presumably did not change patient management. Cancer 2011;. © 2011 American Cancer Society.
    Cancer 03/2011; 117(17):4041 - 4048. · 4.77 Impact Factor
  • Article: Diagnostic yield of percutaneous image-guided tissue biopsy of focal hepatic lesions in cancer patients: ten percent are not metastases from the primary malignancy.
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    ABSTRACT: The diagnostic yield was evaluated of percutaneous image-guided tissue biopsy of hepatic lesions identified on computed tomography performed for staging of a primary malignancy, and it was determined how often the biopsy result was unexpectedly negative, benign, or secondary to a second unknown malignancy. In a retrospective investigation from 1998 through 2008, 580 patients with primary malignancies had indeterminate focal hepatic lesions and underwent percutaneous image-guided biopsy; 369 patients had lesions in their liver at first cross-sectional imaging, performed for staging; 211 patients had a negative liver imaging study, followed by the subsequent appearance of at least 1 indeterminate suspicious lesion. The results of percutaneous image-guided tissue biopsies were compared with the histology of the primary malignancy. Liver biopsies were performed in 580 patients (288 men and 292 women; age, 25-92 years; mean age, 61 years). The most common primary malignancies were pancreatic (n = 96), breast (n = 85), melanoma (n = 57), esophageal (n = 51), lung (n = 47), colorectal (n = 37), and urothelial tumors (n = 26). Biopsy results were positive for malignancy in 528 (91%) cases. Among the positive biopsies, 29 (5%) cases had pathology results different from the primary tumor. Of the 52 biopsies negative for malignancy, 20 yielded a specific benign diagnosis, and 32 were nondiagnostic. If all liver lesions had been assumed to be metastases, as expected secondary to the known primary tumor, then the true or presumed alternate diagnosis would have been missed in 60 (10.3%) of the 580 cases. The authors did not attempt to determine whether actual clinical management changed based on these 60 liver biopsy results, so this number is an upper bound on management change. On the basis of these results, and given the minimal complication rate of liver biopsy, the authors suggest that liver biopsy should still be performed in the types of cases studied here, despite the finding that the vast majority of biopsies produced the expected result and presumably did not change patient management.
    Cancer 03/2011; 117(17):4041-8. · 4.77 Impact Factor
  • Article: False positive diagnosis of metastatic esophageal carcinoma on positron emission tomography: a case report of cholecystitis simulating a hepatic lesion.
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    ABSTRACT: Esophageal cancer has been increasing in incidence for the last several decades. The current staging evaluation includes computed tomography, endoscopic ultrasonography, and F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT), which influences the treatment options. PET/CT is limited in its ability to differentiate hypermetabolic metastatic disease from acute/chronic inflammatory conditions, and this must be considered during interpretation. This is the case report of a 77-year-old man with esophageal cancer whose PET/CT demonstrated increased F-18 FDG uptake in the right lobe of the liver. This was originally interpreted at an outside institution as suspicious for metastatic disease, which would have precluded potential surgical cure. Subsequent reinterpretation and additional imaging including magnetic resonance imaging suggested that the uptake in the liver was likely due to adjacent gallbladder inflammation. On the basis of this interpretation, an abdominal exploration, liver biopsy, cholecystectomy, and transhiatal esophagectomy were performed. Final pathology of the gallbladder revealed perforated cholecystitis and a pericholecystic abscess (related to a prior septic episode), which were responsible for the increased radiotracer uptake. This case is presented to illustrate the importance of considering benign etiologies that may mimic metastatic disease when interpreting PET/CT scans.
    Clinical nuclear medicine 06/2010; 35(6):409-12. · 3.92 Impact Factor
  • Article: Validation of automatic target volume definition as demonstrated for 11C-choline PET/CT of human prostate cancer using multi-modality fusion techniques.
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    ABSTRACT: Positron emission tomography (PET) is actively investigated to aid in target volume definition for radiation therapy. The objectives of this study were to apply an automatic computer algorithm to compute target volumes and to validate the algorithm using histologic data from real human prostate cancer. Various modalities for prostate imaging were performed. In vivo imaging included T2 3-T magnetic resonance imaging and (11)C-choline PET. Ex vivo imaging included 3-T magnetic resonance imaging, histology, and block face photos of the prostate specimen. A novel registration method based on mutual information and thin-plate splines was applied to all modalities. Once PET is registered with histology, a voxel-by-voxel comparison between PET and histology is possible. A thresholding technique based on various fractions of the maximum standardized uptake value in the tumor was applied, and the respective computed threshold volume on PET was compared with histologic truth. Sixteen patients whose primary tumor volumes ranged from 1.2 to 12.6 cm(3) were tested. PET has low spatial resolution, so only tumors > 4 cm(3) were considered. Four cases met this criterion. A threshold value of 60% of the (11)C-choline maximum standardized uptake value resulted in the highest volume overlap between threshold volume on PET and histology. Medial axis distances between threshold volume on PET and histology showed a mean error of 7.7 +/- 5.2 mm. This is a proof-of-concept study demonstrating for the first time that histology-guided thresholding on PET can delineate tumor volumes in real human prostate cancer.
    Academic radiology 02/2010; 17(5):614-23. · 2.09 Impact Factor
  • Article: Detection of aggressive primary prostate cancer with 11C-choline PET/CT using multimodality fusion techniques.
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    ABSTRACT: The aim of the study was to assess whether (11)C-choline PET/CT could identify high-risk primary adenocarcinoma of the prostate. (11)C-choline PET/CT and transpelvic MRI were performed in 14 patients with untreated localized primary adenocarcinoma of the prostate, followed by radical prostatectomy as a form of primary monotherapy within 14 d of in vivo imaging. To allow accurate coregistration of whole-mount histology with in vivo imaging, additional ex vivo MR images of the prostatectomy specimen were obtained. Nonlinear 3-dimensional image deformations were used for registrations of PET/CT, MRI, and histology. Volumes of interest from tumor and benign tissue were defined on the basis of histology and were transferred into coregistered (11)C-choline PET/CT volumes to calculate the mean (T((mean))/B) and maximum (T((max))/B) ratio of tumor to benign prostate background. On the basis of MIB-1/Ki-67 expression in tumor tissues represented on a tissue microarray, we assessed whether (11)C-choline uptake correlated with local Gleason score and tumor proliferation. Histology confirmed 42 tumor nodules with Gleason scores between 3 + 2 and 4 + 4, with volumes ranging from 0.03 to 12.6 cm(3). T((mean))/B (P < 0.01) and T((max))/B (P < 0.001) ratios were significantly increased in high-Gleason score (>or=4 + 3) lesions versus 3 + 4 and lower disease but failed to distinguish between 3 + 4 disease versus 3 + 3 and lower. T((mean))/B and T((max))/B ratios were significantly increased in tumors with an MIB-1/Ki-67 labeling index greater than or equal to 5% (P < 0.01). On the basis of our preliminary data using ratios of tumor to benign prostate background, (11)C-choline preferentially identified aggressive primary prostate cancer.
    Journal of Nuclear Medicine 09/2009; 50(10):1585-93. · 6.38 Impact Factor
  • Article: Registration methodology for histological sections and in vivo imaging of human prostate.
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    ABSTRACT: Registration enables quantitative spatial correlation of features from different imaging modalities. Our objective is to register in vivo imaging with histologic sections of the human prostate so that histologic truth can be correlated with in vivo imaging features. In vivo imaging of the prostate included T2-weighted anatomic and diffusion weighted 3-T magnetic resonance imaging (MRI) as well as 11C-choline positron emission tomography (PET). In addition, ex vivo 3-T MRI of the prostate specimen, histology, and associated block face photos of the prostate specimen were obtained. A standard registration method based on mutual information (MI) and thin-plate spline (TPS) was applied. Registration among in vivo imaging modalities is well established; however, accurate registration involving histology is difficult. Our approach breaks up the difficult direct registration of histology and in vivo imaging into achievable subregistration tasks involving intermediate ex vivo modalities like block face photography and specimen MRI. Results of subregistration tasks are combined to compute the intended, final registration between in vivo imaging and histology. The methodology was applied to two patients and found to be clinically feasible. Overall registered anatomic MRI, diffusion MRI, and 11C-choline PET aligned well with histology qualitatively for both patients. There is no ground truth of registration accuracy as the scans are real patient scans. An indirect validation of the registration accuracy has been proposed comparing tumor boundary markings found in diffusion MRI and histologic sections. Registration errors for two patients between diffusion MRI and histology were 3.74 and 2.26 mm. This proof of concept paper demonstrates a method based on intrinsic image information content for successfully registering in vivo imaging of the human prostate with its post-resection histology, which does not require the use of extrinsic fiducial markers. The methodology successfully mapped histology onto the in vivo imaging space, allowing the observation of how well different in vivo imaging features correspond to histologic truth. The methodology is therefore the basis for a systematic comparison of in vivo imaging for staging of human prostate cancer.
    Academic Radiology 09/2008; 15(8):1027-39. · 1.69 Impact Factor