Focal hepatic lesions: US-guided biopsy--lessons from review of cytologic and pathologic examination results

Clinical benefits of MRI-guided freehand biopsy of small focal liver lesions in comparison to CT guidance

OBJECTIVES

To compare clinical success, procedure time, and complication rates between MRI-guided and CT-guided real-time biopsies of small focal liver lesions (FLL) < 20 mm.

METHODS

A comparison of a prospectively collected MRI-guided cohort (n = 30) to a retrospectively collected CT-guided cohort (n = 147) was performed, in which patients underwent real-time biopsies of small FLL < 20 mm in a freehand technique. In both groups, clinical and periprocedural data, including clinical success, procedure time, and complication rates (classified according to CIRSE guidelines), were analyzed. Wilcoxon rank sum test, Pearson's chi-squared test, and Fisher's exact test were used for statistical analysis. Additionally, propensity score matching (PSM) was performed using the following criteria for direct matching: age, gender, presence of liver cirrhosis, liver lobe, lesion diameter, and skin-to-target distance.

RESULTS

The median FLL diameter in the MRI-guided cohort was significantly smaller compared to CT guidance (p < 0.001; 11.0 mm vs. 16.3 mm), while the skin-to-target distance was significantly longer (p < 0.001; 90.0 mm vs. 74.0 mm). MRI-guided procedures revealed significantly higher clinical success compared to CT guidance (p = 0.021; 97% vs. 79%) as well as lower complication rates (p = 0.047; 0% vs. 13%). Total procedure time was significantly longer in the MRI-guided cohort (p < 0.001; 38 min vs. 28 min). After PSM (n = 24/n = 38), MRI-guided procedures still revealed significantly higher clinical success compared to CT guidance (p = 0.039; 96% vs. 74%).

CONCLUSION

Despite the longer procedure time, freehand biopsy of small FLL < 20 mm under MR guidance can be considered superior to CT guidance because of its high clinical success and low complication rates.

CLINICAL RELEVANCE STATEMENT

Biopsy of small liver lesions is challenging due to the size and conspicuity of the lesions on native images. MRI offers higher soft tissue contrast, which translates into a higher success of obtaining enough tissue material with MRI compared to CT-guided biopsies.

KEY POINTS

• Image-guided biopsy of small focal liver lesions (FLL) is challenging due to inadequate visualization, leading to sampling errors and false-negative biopsies. • MRI-guided real-time biopsy of FLL < 20 mm revealed significantly higher clinical success (p = 0.021; 97% vs. 79%) and lower complication rates (p = 0.047; 0% vs. 13%) compared to CT guidance. • Although the procedure time is longer, MRI-guided biopsy can be considered superior for small FLL < 20 mm.

Predicting successful ultrasound-guided biopsy of liver lesions

OBJECTIVES

To determine the factors that affect successful ultrasound-guided biopsy of liver lesions and build a model predicting feasibility of US-guided liver biopsy.

METHODS

This is IRB-approved HIPAA-compliant retrospective review of consecutive ultrasound-guided targeted liver biopsies performed or attempted between 1/2018 and 9/2020 at a single tertiary academic institution with a total of 501 patients included. Mann-Whitney and chi-square tests were used to compare continuous and categorical variables, respectively. Logistic regression model was built to predict feasibility of successful ultrasound-guided biopsy.

RESULTS

Liver lesion biopsy was successfully performed with US guidance in 429/501 (86%) patients. Lesions not amenable for US biopsy were smaller (median size 1.6 cm vs 3.3 cm, p < 0.0001) and deeper within the liver (median depth 9.0 cm vs 5.8 cm, p < 0.0001). The technical success rate was lowest for lesions in segment II (40/53, 75%), while lesions in segment IVb (87/91, 96%) had highest success rate (p < 0.003). US targeting in patients with 1 or 2 lesions was less feasible than in patients with 3 or more lesions, 126/180 (70%) vs. 303/321 (94%), (p < 0.0001). Model including lesion size, depth, location, and number of lesions predicts feasibility of US-guided biopsy with Area under the ROC curve (AUC) = 0.92.

CONCLUSIONS

Linear logistic regression model that includes lesion size, depth and location, and number of lesions is highly successful in predicting feasibility of ultrasound-guided biopsy for liver lesions. Smaller lesions, deeper lesions, and lesions in segment II and VIII in patients with less than 3 lesions were less feasible for ultrasound-guided biopsy of liver lesions.

Predictors of poor outcome following liver biopsy for the investigation of new hepatic space occupying lesion/s

BACKGROUND

Ultrasound-guided percutaneous liver biopsy (UPLB) is currently performed mainly to determine if new hepatic space occupying lesions (SOL) represent benign, primary malignant, or metastatic disease. This study sought to investigate the outcome of UPLB in this setting.

METHODS

In a retrospective study, patients with a new hepatic SOL who underwent UPLB during 1/2006-12/2016 were included and followed to 12/2018. Clinical data and pathology reports were reviewed. Mortality within 60 days and no change in patients' management following UPLB were defined as medically futile.

RESULTS

Included 140 patients, 50% male, mean age 68.8 ± 11.5 years; 112 patients died, all of malignant disease. 32 patients (23%) died within 60 days of UPLB. Median post-UPLB survival was 151 days. Survival was significantly shorter in patients with >1 hepatic lesion (n = 108) or an extrahepatic malignant lesion (n = 77) (p = 0.0082, p = 0.0301, respectively). On Cox Proportional Hazards analysis, significant predictors of mortality within 60 days of UPLB were: age as a continuous variable, (HR 1.070, 95% CI 1.011-1.131, p = 0.018), serum albumin <2.9 g/dL, (HR 4.822 95% CI 1.335-17.425, p = 0.016) and serum LDH >1500 U/L (HR 9.443, 95% CI 3.404-26.197, p < 0.0001).

CONCLUSIONS

In patients with these features or with disseminated disease, liver biopsy should be carefully reconsidered.

Image-guided intratumoral immunotherapy: Developing a clinically practical technology

Immunotherapy has revolutionized the contemporary oncology landscape, with durable responses possible across a range of cancer types. However, the majority of cancer patients do not respond to immunotherapy due to numerous immunosuppressive barriers. Efforts to overcome these barriers and increase systemic immunotherapy efficacy have sparked interest in the local intratumoral delivery of immune stimulants to activate the local immune response and subsequently drive systemic tumor immunity. While clinical evaluation of many therapeutic candidates is ongoing, development is hindered by a lack of imaging confirmation of local delivery, insufficient intratumoral drug distribution, and a need for repeated injections. The use of polymeric drug delivery systems, which have been widely used as platforms for both image guidance and controlled drug release, holds promise for delivery of intratumoral immunoadjuvants and the development of an in situ cancer vaccine for patients with metastatic cancer. In this review, we explore the current state of the field for intratumoral delivery and methods for optimizing controlled drug release, as well as practical considerations for drug delivery design to be optimized for clinical image guided delivery particularly by CT and ultrasound.

The Use of the Transfemoral Transcaval Liver Biopsy Technique for Biopsies of Hepatic Masses

The purpose of this study was to investigate the safety and effectiveness of the transfemoral transcaval (TFTC) liver biopsy technique in patients with hepatic masses with relative contraindications to percutaneous biopsy and/or mass location abutting the inferior vena cava. The medical records of 16 patients (56% men; age range, 21-88 years) who underwent TFTC biopsy of hepatic masses (ranging in diameter from 2.1 to 13.2 cm) from September 2015 to August 2021 were reviewed. Histopathologic diagnoses were made in 15 of 17 (88%) procedures. Two adverse events were noted: worsened preexisting hemobilia requiring embolization in 1 patient, and a decrease in hematocrit level in another patient, requiring only observation. In conclusion, this report showed that the TFTC technique is a relatively safe and effective method for sampling hepatic masses in select cases.

Presence of Color Transition in Biopsy Specimens Predicts Outcome of Liver Lesion Biopsies

Background

The aim of this study was to evaluate the usefulness of the presence of tissue transition in liver lesion biopsies to predict a successful outcome, as observed by modified macroscopic on-site evaluation (MOSE).

Methods

This is a retrospective analysis of 264 ultrasound-guided liver lesion biopsies, examining the influence the presence of tissue transition (visible color changes in biopsy specimens as evaluated visually) has on two endpoints (1) material retrieval, (2) attaining a definitive diagnosis) representing successful liver lesion biopsies, compared to previously evaluated variables in this context. Uni- and multivariate analyses were performed using SPSS 21.0.

Results

Material retrieval and a definitive diagnosis occurred in 224/264 (84.8%) and 217/264 (82.2%) cases, the latter occurring more often when visual inspection revealed macroscopic tissue transition (92/96 [95.8%]) than when not (124/165 [75.2%]), P < 0.001. Tissue transition in biopsies was more common in secondary (74/162 [45.7%]) than (18/54 [33.3%]) primary liver lesions, though this was not significant (P = 0.112). On multivariate analysis, tissue transition in biopsies was an independent predictor of a definitive diagnosis and material retrieval.

Conclusion

In liver lesion biopsies, MOSE of color transition in biopsies can indicate success. This is easily incorporated into clinical practice and can help overcome the lack of an on-site pathologist.

Image-guided Percutaneous Biopsy of the Liver

Percutaneous Biopsy of the Liver (PBL) is a cornerstone in the diagnosis of parenchymal liver disease and focal hepatic lesions. The indications for PBL can broadly be divided into those used to garner information regarding diagnosis, prognosis, or treatment. While the diagnosis of many common liver diseases can usually be made with imaging and serologic testing alone, PBL may be indicated in situations where the diagnosis is in question. Furthermore, liver biopsies are a foundational element for personalized treatment approaches for cancer patients; increasing emphasis is being placed on acquiring sufficient tissue for molecular profiling. While a variety of image guidance and procedural techniques have been applied to PBL, following conventional principles can ensure technical success and minimize complication risks. In this technique article, we review the practical periprocedural considerations of PBL with emphasis on recent advancements and societal recommendations.

Optimizing clinical cytology touch preparations for next generation sequencing

Intraoperative diagnosis is routinely performed on cytology touch preparations (TPs) from core needle biopsies (CNBs). Current interest promotes their utility as an important source of patient tissue for clinical genomic testing. Herein we present whole genome structural variant analysis (SVA) from mate-pair sequencing (MPseq) and whole exome sequencing (WES) mutation calling in DNA directly whole genome amplified (WGA) from TPs. Chromosomal copy changes and somatic DNA junction detection from MPseq of TPs were highly consistent with associated CNBs and bulk resected tissues in all cases. While increased frequency coverage noise from limitations of amplification of limited sample input was significant, this was effectively compensated by natural tumor enrichment during the TP process, which also enhanced variant detection and loss of heterozygosity evaluations from WES. This novel TP methodology enables expanded utility of frequently limited CNB for both clinical and research genomic testing.

Utilization of Dynamic Telecytopathology for Rapid Onsite Evaluation of Touch Imprint Cytology of Needle Core Biopsy: Diagnostic Accuracy and Pitfalls

Background: In the era of personalized medicine, there has been an increase in demand on cytopathology service to perform rapid onsite evaluation of touch imprints (ROSETIs) of needle core biopsies (NCBs) to ensure sample adequacy and provide preliminary diagnosis. Limited publications have addressed use of telecytopathology for ROSETIs. We present our experience with telecytopathology-guided ROSETIs of NCBs. Materials and Methods: Cytotechnologist onsite transmitted real-time images of Diff-QUIK stained touch imprints of NCBs using an Olympus digital camera through Ethernet to a pathologist. The preliminary diagnosis from telecytopathology-guided ROSETIs was compared with that of the final NCB for diagnostic accuracy. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Results: Of 186 cases, 163 (87%) were concordant and 23 (13%) were discordant. Of the 23 discordant cases, 14 (58%) were diagnosed as benign with final NCB diagnoses as malignant and 9 (41%) were suspicious on ROSETIs with final NCB diagnoses as benign. The causes of discordance among cases categorized as benign on preliminary and malignant on final included interpretative error (9) and sampling (6). Six cases categorized as suspicious on preliminary and negative on final biopsy diagnosis correlated with concurrent fine-needle aspiration, raising the possibility of loss of diagnostic areas in processed tissue cores. Remaining three cases in this category represented misinterpretation of reactive cells. Sensitivity, specificity, PPV, and NPV were 87.9%, 95.7%, 97.1%, and 82.7%, respectively. Conclusions: Telecytopathology-guided ROSETI yields high accuracy for preliminary interpretation of NCBs and may be utilized as an effective substitute for conventional microscopy.

US LI-RADS visualization score: diagnostic outcome of ultrasound-guided focal hepatic lesion biopsy in patients at risk for hepatocellular carcinoma

PURPOSE

This study investigated the diagnostic outcome of ultrasound (US)-guided focal hepatic lesion biopsy in patients at risk for hepatocellular carcinoma (HCC) and evaluated the US visualization score as a risk factor for non-diagnostic results.

METHODS

We retrospectively evaluated 208 focal hepatic lesions in 208 patients who underwent US-guided biopsy in 2016. Using the US Liver Imaging Reporting and Data System version 2017, each exam was assigned a US visualization score (A, B, or C). Final diagnoses were made using pathology reports, and biopsy results were categorized as diagnostic or non-diagnostic. Univariable and multivariable analyses were performed to determine risk factors for non-diagnostic results, including US visualization score and other clinical covariates.

RESULTS

Of the 208 lesions, 85.1% were diagnostic and 14.9% were non-diagnostic. The rates of non-diagnostic results were 8.9%, 25.5%, and 57.1% for scores of A, B, and C, respectively. In the univariable analysis, scores of B or C were associated with a significantly higher rate of nondiagnostic results than scores of A (58.1% vs. 24.9%, P<0.001). In the multivariable analysis, US visualization score of B or C (adjusted odds ratio [aOR], 2.7; P=0.027), high-risk needle pathway usage (aOR, 5.7; P=0.001), and lesion size ≤2.0 cm (aOR, 2.7; P=0.024) were independent risk factors for non-diagnostic results.

CONCLUSION

US-guided biopsy had a high diagnostic yield for focal hepatic lesions in patients at risk for HCC. US visualization score of B or C, lesion size ≤2.0 cm, and high-risk needle pathway usage were independent risk factors for non-diagnostic results.

Ultrasound-guided non-targeted liver core biopsy: comparison of the efficacy of two different core needle biopsy systems using an ex-vivo animal model and retrospective review of clinical experience

PURPOSE

To compare the efficacy of two 18-gauge core needle biopsy systems, the Achieve® (Merit Medical) and the Marquee® (BD Bard), using an ex-vivo animal liver model and retrospective review of clinical experience.

METHODS

Sixty ex-vivo liver biopsy samples were obtained using the Achieve® (n = 30) and the Marquee® (n = 30) needles. In addition, 20 liver biopsy samples from 20 patients obtained using the Achieve® (n = 10) and Marquee® (n = 10) were compared retrospectively. One pathologist, blinded to needle type, recorded total core length and the number of complete portal triads. Ex vivo measurements were compared using mixed effects linear, logistic, and ordinal regression. In vivo measurements were compared using Student's t-test.

RESULTS

For the Achieve® and Marquee® needles, the mean(SD) total core length (mm) of ex vivo samples was 11.0(3.3) and 12.6(3.4), respectively (P = 0.069) and the adequacy rate was 23.3% and 50%, respectively (P = 0.04). Mean number of portal triads of ex vivo samples was 7.2(2.9) and 8.6(3.8), respectively (P = 0.13), and the adequacy rate was 73.3% and 83.3%, respectively (P = 0.32). For in vivo samples, the Achieve® and Marquee® needles demonstrates mean(SD) total core length (mm) of 24.6(7.1) and 32.0(4.6), respectively (P = 0.01), adequacy rate (P = 0.06). Mean number of portal triads was 14.9(4.8) and 19.6(4.1), respectively (P = 0.03), adequacy rate (P = 0.47).

CONCLUSIONS

Slightly longer core biopsies were obtained with the Marquee® needle compared with the Achieve® needle. Early clinical experience demonstrates no significant difference in sample adequacy rates. Both needle types can be expected to provide adequate samples for pathologic assessment of liver tissue.

Negative Biopsy of Focal Hepatic Lesions: Decision Tree Model for Patient Management

OBJECTIVE

The purpose of this study was to investigate patient- and procedure-related variables affecting the false-negative rate of ultrasound (US)-guided liver biopsy and to develop a standardized patient-tailored predictive model for the management of negative biopsy results.

MATERIALS AND METHODS

We retrospectively included 389 patients (mean age ± SD, 62 ± 12 years old) who had undergone US-guided liver biopsy of 405 liver lesions between January 1, 2013, and June 30, 2015. We collected multiple patient- and procedure-related variables. By comparing pathology reports of biopsy and the reference standard (further histology or imaging follow-up), we were able to categorize the biopsy results as true-positive, true-negative, and false-negative. Diagnostic accuracy and diagnostic yield were measured. Univariate and multivariate analyses were performed to identify variables predicting false-negative results. A standardized patient-tailored predictive model of false-negative results based on a decision tree was fitted.

RESULTS

Diagnostic accuracy and diagnostic yield were 93.8% (380/405) and 89.4% (362/405), respectively. The false-negative rate was 6.5% (25/387). Predictive variables of false-negative results at univariate analysis included body mass index, lesion size, sample acquisition techniques, and immediate specimen adequacy. The only independent predictors at multivariate analysis were patient age and Charlson comorbidity index. By combining lesion size and location with patient age and history of malignancy, we developed a decision tree model that predicts false-negative results with high confidence (up to 100%).

CONCLUSION

False-negative results are not negligible at US-guided liver biopsy. The combination of selected lesion- and patient-specific variables may help predict when aggressive management is warranted in patients with likely false-negative results.

Utility of rapid on-site evaluation for needle core biopsies and fine-needle aspiration cytology done for diagnosis of mass lesions of the liver

BACKGROUND

Fine-needle aspiration (FNA) and core biopsy (CB) are used to diagnose liver lesions. Rapid onsite evaluation (ROSE) can improve the adequacy of the procedures and help triage diagnostic material appropriately. There are very few studies evaluating the role of ROSE for CB and FNA of mass lesions of the liver.

METHODS

Liver cases with ROSE material from 2007 to 2017 were retrieved and reviewed. The ROSE material was re-evaluated by 2 cytopathologists who were blinded to the final diagnosis. Data including age, number of lesions, number of passes, adequacy assessed at time of procedure, and diagnosis made by cytopathologist on ROSE material at time of re-review was compiled.

RESULTS

A total of 82 cases were identified; 33 were primary lesions (group A) and 49 were metastatic lesions (group B). ROSE done by cytotechnologist at time of procedure showed an adequacy rate of 84%. During re-review of ROSE material by cytopathologists, the overall adequacy rates were similar, although the adequacy rates in group B increased (to 100% from 92%) and it dropped in group A (from 73% to 52%). The overall accuracy rate was 90%. Hepatocellular adenoma, regenerative nodules, well-differentiated hepatocellular carcinoma, and angiosarcoma were not possible to diagnose on smears alone during ROSE.

CONCLUSIONS

ROSE for liver lesions is useful for assessing adequacy. Certain lesions cannot be accurately diagnosed on ROSE alone. ROSE material when assessed by cytopathologist can improve adequacy rate and possibly decrease number of nondiagnostic specimens in group A, though the cost effectiveness needs to be assessed.

Utility and Safety of Repeated Ultrasound-Guided Core Needle Biopsy of Focal Liver Masses

OBJECTIVES

To evaluate the accuracy and safety of repeated ultrasound-guided core needle biopsy (CNB) for hepatic focal lesions and to assess the predictive factors for success of repeated CNB.

METHODS

For 5 years, 3085 CNBs were performed for focal hepatic lesions using an automated biopsy gun with an 18-gauge needle. Seventy-eight patients underwent repeated CNB because of pathologically inconclusive or unexpected results. Twelve patients were excluded because of unavailable additional tissue or follow-up imaging by radiofrequency ablation (n = 5), repeated CNB greater than than 3 months after the first CNB (n = 5), and insufficient follow-up time (n = 2). Sixty-six patients were finally enrolled after the exclusion criteria were applied. We retrospectively evaluated tumor necrosis, tumor size, number of passes, lesion site, depth, tumor conspicuity, and complications. Continuous data and the total scores of the grading system were analyzed by the Student t test, and categorical data and each category were analyzed by the Fisher exact test.

RESULTS

The repeated CNB rate was 2.5% (78 of 3085). The diagnostic accuracy of the repeated biopsies was 83.3% (55 of 66). Comparing the diagnostic group with the nondiagnostic group, no variable (ie, size, depth, necrosis, lesion site [segment], and number of passes) had a statistically significant difference. Tumor conspicuity was a significant factor for predicting successful repeated biopsy (P < .001). The cumulative complication rate was 10.6% (7 of 66), with only minor complications.

CONCLUSIONS

Repeated CNB is an accurate and safe procedure for obtaining a histologic diagnosis of hepatic focal lesions if the initial biopsy fails. High tumor conspicuity showed a significant correlation with successful repeated CNB.

Utility of T1-weighted MRI as a predictor of liver lesion visibility on ultrasound: A clinical tool to determine feasibility of ultrasound-guided percutaneous interventions

PURPOSE

To determine the utility of fat-suppressed T1-weighted gradient recalled echo (FS-T1W-GRE) MRI to predict visibility of focal liver lesions (FLL) on abdominal ultrasound (US).

MATERIALS AND METHODS

With IRB approval, between 2010 and 2013, 109 patients (28.4% females, age 66.9±10.9years) with 177 FLL (hepatocellular carcinoma=132, metastases=44, other=1) underwent MRI and prospective, radiologist-performed treatment-planning US (to determine eligibility for US-guided ablation). MRI examinations were reviewed by a blinded radiologist who assessed: a) size and location of FLL, b) presence of hepatic steatosis on dual-echo T1W-GRE, and c) quantitative signal intensity of FLL relative to liver on FS-T1W-GRE. Associations between MR imaging findings and visibility on US were assessed using independent t-tests and the chi-squares test.

RESULTS

69.5% (123/177) FLL were identified with US and 30.5% (54/177) were not visible. Size of FLL on MRI was associated with visibility on US (p<0.0001) with no association between FLL visibility on US and segmental or subcapsular location (p=0.29 and p=0.25, respectively). 20.2% (22/109) patients had hepatic steatosis on MRI, which was not associated with non-visibility of FLL on US (p=0.67). 38.4% (68/177) FLL were isointense to liver on FS-T1W-GRE which was associated with non-visibility on US (p=0.036) particularly in non-steatotic livers (p=0.014).

CONCLUSION

FLL size and isointensity of FLL to liver parenchyma on FS-T1W-GRE MRI are associated with non-visibility on US, particularly in non-steatotic livers. These results have implications when planning US-guided percutaneous interventions of FLL detected with MRI.

Ultrasound-Guided Percutaneous Core Needle Biopsy of Abdominal Viscera: Tips to Ensure Safe and Effective Biopsy

Ultrasound-guided percutaneous core needle biopsy (USPCB) is used extensively in daily clinical practice for the pathologic confirmation of both focal and diffuse diseases of the abdominal viscera. As a guidance tool, US has a number of clear advantages over computerized tomography or magnetic resonance imaging: fewer false-negative biopsies, lack of ionizing radiation, portability, relatively short procedure time, real-time intra-procedural visualization of the biopsy needle, ability to guide the procedure in almost any anatomic plane, and relatively lower cost. Notably, USPCB is widely used to retrieve tissue specimens in cases of hepatic lesions. However, general radiologists, particularly beginners, find USPCB difficult to perform in abdominal organs other than the liver; indeed, a full understanding of the entire USPCB process and specific considerations for specific abdominal organs is necessary to safely obtain adequate specimens. In this review, we discuss some points and techniques that need to be borne in mind to increase the chances of successful USPCB. We believe that the tips and considerations presented in this review will help radiologists perform USPCB to successfully retrieve target tissue from different organs with minimal complications.

Imprint cytopathology of core needle biopsies: a "first responder" role for cytotechnologists

INTRODUCTION

Imprint cytopathology (IC) of image-guided core needle biopsies (CNBs) is used to ensure adequate sampling. In our institution, cytotechnologists (CyTs) are the "first responders" for on-site adequacy assessment (OSAA) of image-guided CNBs. We report our experience with this expanded and relatively unexplored role for CyT.

MATERIALS AND METHODS

We reviewed all image-guided CNBs performed over a 12-month period that required OSAA. OSAA was provided primarily by CyT. Interpretation between all IC specimens and tissue diagnoses (concordance) and between adequate IC specimens and tissue diagnoses (accuracy) were analyzed. Performance was compared using the Fisher exact test. We retrospectively reviewed discrepant cases to deduce the reasons for discordance.

RESULTS

We evaluated 255 CNBs: 179 computed tomography-guided, 74 ultrasonography-guided, 2 endoscopy-guided. Lung (39%) followed by liver (16%) and lymph node (11%) were the most frequent sites of OSAA IC. Overall adequacy and accuracy rates were 80.8% and 87.9%, respectively, with a concordance rate of 81.2%. The performance for CyT alone, CyT/cytopathology fellow, and CyT/cytopathologist were comparable (P > 0.05). Review of discordant cases showed agreement with 91% of OSAA IC cases originally interpreted as inadequate, but with only 19% interpreted as adequate.

CONCLUSIONS

OSAA IC of CNBs expands the CyT's role in an effort to ensure adequate sampling. CyT performance was high in recognition of adequate versus inadequate IC slides when compared with the tissue. Reasons for discrepancy included sampling error and overinterpretation of atypia as being sufficient evidence of adequacy. Organ-specific cytologic criteria to assess adequacy are required to reduce interpretation error.

Impact of touch preparations on core needle biopsies

BACKGROUND

Touch preparations (TPs) can be performed for on-site adequacy assessment of core needle biopsies (CNBs). Although TPs can play a role in decreasing the number of nondiagnostic core biopsies, the impact of TPs on CNB has not been extensively evaluated.

METHODS

Computerized tomography-guided CNBs performed in a tertiary cancer center were retrospectively identified. On-site adequacy assessment was performed in all cases. The matching TPs and CNBs were evaluated for diagnostic accuracy of the TP. The relation between the site of biopsy and the cellularity of the CNB was also analyzed.

RESULTS

A total of 1100 CNB cases with associated TPs were identified over a 6-month period. Eighty-four cases (8%) showed marked differences in cellularity between CNB and TP, and 43 of these 84 cases (4.3%) showed the presence of diagnostic cells in either CNB or TP, but not in both. Lung was the biopsy site where CNB was most affected by loss of diagnostic cells.

CONCLUSIONS

TP and CNB findings must be integrated to prevent a misdiagnosis. Lung CNBs were more frequently affected by performing TPs.

Role of FNA and Core Biopsy of Primary and Metastatic Liver Disease

Objective. To examine our experience with cytology and histology biopsy of the liver and to define methods for improvement of diagnosis of primary liver tumors. Methods. This include retrospective study of 189 biopsies of 185 liver masses for cytological or histological analysis. Patients were subdivided into two groups. Group 1 consisted of 124 suspected metastasis. Group 2 consisted of 61 suspected primary neoplasms. Biopsies were considered positive or equivocal. In equivocal cases, special stains were performed. In Group 2, cases were classified by contrast CT or MRI as to (I) classic HCC, (II) infiltrated HCC, or (Ill) equivocal. Results. Definitive diagnosis was obtained in 117/124 masses (94%) in Group 1, 48/61 masses (79%) in Group 2, and (Ill) equivocal 13 cases in Group II. In two equivocal cases in which special stains were performed, they were reclassified as HCC. In 8/13 cases, CT findings were consistent with HCC. Conclusion. Liver biopsies are useful in obtaining a definitive diagnosis of suspected metastatic liver disease. Biopsy results are less reliable in patients with suspected primary liver tumors. In these situations, strategies can include basing treatment on imaging criteria or use of newer special pathological stains. Advances in Knowledge. Use of newer special immunological stains improves accuracy in definitive diagnosis of primary liver tumors.

The importance of experience in percutaneous liver biopsies guided with ultrasonography: a lesion-focused approach

RATIONALE AND OBJECTIVES

The goal of this study is to emphasize the value of lesion-focused approach in ultrasonography (US)-guided solid liver lesion biopsies performed under our guidance.

MATERIALS AND METHODS

In our retrospective study, after the standard preparation for US-guidance solid liver lesion biopsy was accomplished, we performed standard intercostal approach and the biopsy procedure though one of our patients experienced a major complication (pneumothorax). After this undesirable case, we reviewed our biopsy procedure and performed a lesion-focused approach technique as described in this article. A Tru-cut biopsy gun (18 gauge) was used in this trial. The liver biopsies were divided into two groups according to the biopsy technique and all results were compared with each other.

RESULTS

A total of 202 solid liver lesion biopsies were was performed under the guidance of US between October 2007 and July 2010. One major complication occurred in first group. All of the minor complications occurred in the first group. In group 2, there were no complications. For this reason, all patients in group 2 were discharged home after a few hours. Patients with minor complications in the first group were observed an average of 6 hours. Adequate tissue for pathological diagnosis was similar in both groups.

CONCLUSION

The lesion-focused approach technique has the potential to reduce both complication rates and patient incompliance. Percutaneous liver biopsies performed with this technique using real-time US guidance are convincing and clinically beneficial.

Primary colorectal cancers and their subsequent hepatic metastases are genetically different: implications for selection of patients for targeted treatment

PURPOSE

In the era of DNA-guided personalized cancer treatment, it is essential to conduct predictive analysis on the tissue that matters. Here, we analyzed genetic differences between primary colorectal adenocarcinomas (CRC) and their respective hepatic metastasis.

EXPERIMENTAL DESIGN

The primary CRC and the subsequent hepatic metastasis of 21 patients with CRC were analyzed using targeted deep-sequencing of DNA isolated from formalin-fixed, paraffin-embedded archived material.

RESULTS

We have interrogated the genetic constitution of a designed "Cancer Mini-Genome" consisting of all exons of 1,264 genes associated with pathways relevant to cancer. In total, 6,696 known and 1,305 novel variations were identified in 1,174 and 667 genes, respectively, including 817 variants that potentially altered protein function. On average, 83 (SD = 69) potentially function-impairing variations were gained in the metastasis and 70 (SD = 48) variations were lost, showing that the primary tumor and hepatic metastasis are genetically significantly different. Besides novel and known variations in genes such as KRAS, BRAF, KDR, FLT1, PTEN, and PI3KCA, aberrations in the up/downstream genes of EGFR/PI3K/VEGF-pathways and other pathways (mTOR, TGFβ, etc.) were also detected, potentially influencing therapeutic responsiveness. Chemotherapy between removal of the primary tumor and the metastasis (N = 11) did not further increase the amount of genetic variation.

CONCLUSION

Our study indicates that the genetic characteristics of the hepatic metastases are different from those of the primary CRC tumor. As a consequence, the choice of treatment in studies investigating targeted therapies should ideally be based on the genetic properties of the metastasis rather than on those of the primary tumor.

Magnetic resonance imaging of focal liver lesions: approach to imaging diagnosis

This article is a review of magnetic resonance imaging (MRI) of incidental focal liver lesions. This review provides an overview of liver MRI protocol, diffusion-weighted imaging, and contrast agents. Additionally, the most commonly encountered benign and malignant lesions are discussed with emphasis on imaging appearance and the diagnostic performance of MRI based on a review of the literature.

Evaluation of analgesic effect of equimolar mixture of oxygen and nitrous oxide inhalation during percutaneous biopsy of focal liver lesions: a double-blind randomized study

RATIONALE AND OBJECTIVES

Percutaneous liver biopsy for tumors performed under local anesthesia is still a painful procedure. The aim of this study was to evaluate the patient's reaction and the analgesic efficacy and safety of an equimolar mixture of oxygen and nitrous oxide (EMONO) inhalation.

MATERIALS AND METHODS

A monocenter, prospective, randomized and double-blind controlled study was performed including 99 adult patients undergoing ultrasound controlled liver biopsy for tumors. 50 patients received an EMONO and 49 patients received a placebo. Pain was evaluated by patients before and after the procedure using a Visual Analog Scale.

RESULTS

Analgesic control, defined by the difference between the final and initial VAS scores (Δ), was significantly better in the EMONO group than in the placebo group (Δ = 17.8 ± 25.5 mm vs 30.1 ± 32.6 mm; P = .045. The number of patients who would agree to undergo another liver biopsy under the same conditions was significantly higher in the EMONO group than the placebo group (92.0% vs 75.5%, P = .026). There were no side-effects from the administration of an EMONO.

CONCLUSION

This study shows that patients receiving an EMONO had a higher analgesic control after percutaneous biopsy of focal liver lesions than patients in the placebo group. Moreover, acceptance of additional biopsies was higher in the EMONO group.

Ultrasound-guided biopsy of focal lesions using three-dimensional ultrasound with a matrix array transducer: comparison with 2-dimensional ultrasound in a phantom study

OBJECTIVES

To investigate the feasibility of biopsy-guided 3-dimensional (3D) ultrasound (US) with a matrix array transducer (3D US-MAT), using the lateral and/or elevation tilt modes.

MATERIALS AND METHODS

Both inexperienced and experienced examiners performed biopsy experiments using a freehand technique on agar-based phantoms with 2-dimensional (2D) US guidance and 3D US-MAT guidance allowing real-time biplane imaging, using the lateral tilt mode and/or elevation tilt mode. Each phantom contained 4 targets of different sizes, and there were 3 different types of phantom, each having a different distance between the target and the surface. In every session, each target was aimed at 3 times, with 3 different distances between the transducer and puncture site, which resulted in 36 biopsies (3 biopsies per target × 4 targets × 3 phantoms, each of which was uniquely identified by size, depth, and angle). This procedure was carried out by each of 2 examiner twice by 2D US and twice by 3D US-MAT, resulting in paired data for each biopsy and each examiner. Target variables were target specimen length (TSL), procedure time, and agreement between the TSL of the first and second procedure by each examiner with identical biopsy parameters as a reliability measure.

RESULTS

The intraexaminer agreements between the TSLs with the 3D US-MAT in both inexperienced (r = 0.84) and experienced (r = 0.93) examiners were higher than with the 2D US (r = 0.59 with P = 0.0066, and r = 0.87 with P = 0.06, respectively). However, the procedure time with the 3D US-MAT was significantly longer than with the 2D US. The TSL were significantly longer with 3D US-MAT than with 2D US for both the examiners; the inexperienced examiner (P < 0.001) benefited more than his experienced colleague (P = 0.024). In addition, the 3D US-MAT had significant benefits for the acquisition of TSL with small target diameters and for targets with shallow locations; with more acute puncture angles for both the examiners (all P < 0.05).

CONCLUSIONS

Using a 3D US-MAT guidance improves the reliability and precision of biopsies, particularly under difficult conditions and for inexperienced examiners.

Success of image-guided biopsy for small (≤ 3 cm) focal liver lesions in cirrhotic and noncirrhotic individuals

PURPOSE

Imaging techniques can detect small liver lesions, although these are a challenge to biopsy, particularly in cirrhotic liver. The authors assessed the diagnostic success of image-guided biopsies collected from small (≤ 3 cm) focal liver lesions.

MATERIALS AND METHODS

This single-center, retrospective study included 374 patients (199 men; mean age, 62 ± 15). Eighteen-gauge core biopsy and 22-gauge fine needle aspiration (FNA) samples were collected from small focal liver lesions. Samples were compared by histology versus cytology, malignant versus benign, from lesions smaller versus larger than 1.5 cm, from livers with versus without cirrhosis, collected by computed tomography (CT) guidance versus ultrasound, and from different locations in the liver.

RESULTS

The combined accuracy of core biopsy plus FNA analysis was 95.5%; core biopsy alone characterized 93.3% of samples, and FNA alone characterized 72.5% (P < .001). Biopsy successfully characterized 94.5% of malignant lesions and 98.8% of benign lesions (P > .05). Biopsy characterized 95.3% (102 of 107) lesions ≤ 1.5 cm. The success in cirrhotic livers was 94.8%, for CT-guided biopsies was 95%, and for ultrasound-guided biopsies was 95.8% (P > .05). The success rate was lower in liver caudate lobe than in other locations (P < .05).

CONCLUSIONS

Image-guided biopsy of small (≤ 3 cm) focal liver lesions is highly reliable with the use of core biopsy alone. Neither size ≤ 1.5 cm nor presence of cirrhosis is an impediment to biopsy. CT and ultrasound guidance produce similar rates of success.