Reducing Time and Patient Radiation of Computed Tomography-guided Thoracic Needle Biopsies With Single-rotation Axial Acquisitions: An Alternative to "CT Fluoroscopy"

Imaging Guidelines during Percutaneous Liver Ablation to Optimize Outcomes and Patient Safety

Image-guided ablation procedures have become a mainstay in cancer therapy. Typically performed from a percutaneous approach, thermal-based ablation procedures rely heavily on imaging guidance both prior to and during the procedure itself. Advances in imaging as they relate to ablation procedures are as important to successful treatments as advancements in the ablation technology itself. Imaging as it relates to procedural planning, targeting and monitoring, and assessment of procedural endpoint is the focus of this article.

Routine radiology-pathology concordance evaluation of CT-guided percutaneous lung biopsies increases the number of cancers identified

BACKGROUND

Routine concordance evaluation between pathology and imaging findings was introduced for CT-guided biopsies.

PURPOSE

To analyze malignancy rate in concordant, discordant, and indeterminate non-malignant results of CT-guided lung biopsies.

METHODS

Concordance between pathology results and imaging findings of consecutive patients undergoing CT-guided lung biopsy between 7/1/2016 and 9/30/2021 was assessed during routine meetings by procedural radiologists. Concordant was defined as pathology consistent with imaging findings; discordant was used when pathology could not explain imaging findings; indeterminate when pathology could explain imaging findings but there was concern for malignancy. Recommendations for discordant and indeterminate were provided. All the malignant results were concordant. Pathology of repeated biopsy, surgical sample, or follow-up was considered reference standard.

RESULTS

Consecutive 828 CT-guided lung biopsies were performed on 795 patients (median age 70 years, IQR 61-77), 423/828 (51%) women. On pathology, 224/828 (27%) were non-malignant. Among the non-malignant, radiology-pathology concordance determined 138/224 (62%) to be concordant with imaging findings, 54/224 (24%) discordant, and 32/224 (14%) indeterminate. When compared to the reference standard, 33/54 (61%) discordant results, 6/30 (20%) indeterminate, and 3/133 (2%) concordant were malignant. The prevalence of malignancy in the three groups was significantly different (p < 0.001). Time to diagnosis was significantly different between patients who reached the diagnosis with imaging follow-up (median 114 days, IQR 69-206) compared to repeat biopsy (33 days, IQR 18-133) (p = 0.01).

CONCLUSION

Routine radiology-pathology concordance evaluation of CT-guided lung biopsy correctly identifies patients at high risk for missed diagnosis of malignancy. Repeat biopsy is the fastest method to reach diagnosis.

CLINICAL RELEVANCE STATEMENT

A routine radiology-pathology concordance assessment identifies patients with non-malignant CT-guided lung biopsy result who are at greater risk of missed diagnosis of malignancy.

KEY POINTS

• A routine radiology-pathology concordance evaluation of CT-guided lung biopsies classified 224 non-malignant results as concordant, discordant, or indeterminate. • The percentage of malignancy on follow-up was significantly different in concordant (2%), discordant (61%), and indeterminate (20%) (p < 0.001). • Time to definitive diagnosis was significantly shorter with repeat biopsy (33 days), compared to imaging follow-up (114 days), p = 0.01.

High-Frequency Jet Ventilation Versus Spontaneous Respiration for Percutaneous Cryoablation of Lung Tumors: Comparison of Adverse Events and Procedural Efficiency

BACKGROUND. High-frequency jet ventilation (HFJV) facilitates accurate probe placement in percutaneous ablation of lung tumors but may increase risk for adverse events, including systemic air embolism. OBJECTIVE. The purpose of this study was to compare major adverse events and procedural efficiency of percutaneous lung ablation with HFJV under general anesthesia to spontaneous respiration (SR) under moderate sedation. METHODS. This retrospective study included consecutive adults who underwent CT-guided percutaneous cryoablation of one or more lung tumors with HFJV or SR between January 1, 2017, and May 31, 2023. We compared major adverse events (Common Terminology Criteria for Adverse Events grade ≥ 3) within 30 days postprocedure and hospital length of stay (HLOS) of 2 days or more using logistic regression analysis. We compared procedure time, room time, CT guidance acquisition time, CT guidance radiation dose, total radiation dose, and pneumothorax using generalized estimating equations. RESULTS. Overall, 139 patients (85 women, 54 men; median age, 68 years) with 310 lung tumors (82% metastases) underwent 208 cryoablations (HFJV, n = 129; SR, n = 79). HFJV showed greater rates than SR for the treatment of multiple tumors per session (43% vs 19%, respectively; p = .02) and tumors in a nonperipheral location (48% vs 24%, p < .001). Major adverse event rate was 8% for HFJV and 5% for SR (p = .46). No systemic air embolism occurred. HLOS was 2 days or more in 17% of sessions and did not differ significantly between HFJV and SR (p = .64), including after adjusting for probe number per session, chronic obstructive pulmonary disease, and operator experience (p = .53). Ventilation modalities showed no significant difference in procedure time, CT guidance acquisition time, CT guidance radiation dose, or total radiation dose (all p > .05). Room time was longer for HFJV than SR (median, 154 vs 127 minutes, p < .001). For HFJV, the median anesthesia time was 136 minutes. Ventilation modalities did not differ in the frequencies of pneumothorax or pneumothorax requiring chest tube placement (both p > .05). CONCLUSION. HFJV appears to be as safe as SR but had longer room times. HFJV can be used in complex cases without significantly impacting HLOS of 2 days or more, procedure time, or radiation exposure. CLINICAL IMPACT. Selection of the ventilation modality during percutaneous lung ablation should be based on patient characteristics and anticipated procedural requirements as well as operator preference.

Prediction of Complication Risk in Computed Tomography-guided Thoracic Biopsy: A Prescription for Improving Procedure Safety

PURPOSE

Computed tomography-guided transthoracic biopsy (CTTB) is a minimally invasive procedure with a high diagnostic yield for a variety of thoracic diseases. We comprehensively assessed a large CTTB cohort to predict procedural and patient factors associated with the risk of complications.

MATERIALS AND METHODS

The medical record and computed tomography images of 1430 patients who underwent CTTB were reviewed individually to obtain clinical information and technical procedure factors. Statistical analyses included descriptive and summary statistics, univariate analysis with the Fisher test, and multivariate logistic regression.

RESULTS

The most common type of complication was pneumothorax (17.4%), followed by bleeding (5.9%). Only 26 patients (1.8%) developed a major complication. Lung lesions carried a higher risk of complications than nonlung lesions. For lung lesions, the nondependent position of the lesion, vertical needle approach, trespassing aerated lung, and involvement of a trainee increased the risk of complication, whereas the use of the coaxial technique was a protective factor. The time with the needle in the lung, the number of biopsy samples, and the distance crossing the aerated lung were identified as additional risk factors in multivariate analysis. For nonlung lesions, trespassing the pleural space was the single best predictor of complications. A logistic regression-based model achieved an area under the receiver operating characteristic curve of 0.975, 0.699, and 0.722 for the prediction of major, minor, and no complications, respectively.

CONCLUSIONS

Technical procedural factors that can be modified by the operator are highly predictive of the risk of complications in CTTB.

Optimizing molecular testing of lung cancer needle biopsy specimens: potential solutions from an interdisciplinary qualitative study

BACKGROUND

Molecular testing can detect actionable genomic alterations and tumor cell surface proteins in patients with non-small cell lung cancer (NSCLC). However, utilization remains suboptimal, representing missed treatment opportunities. This study aimed to identify challenges and potential solutions to obtaining percutaneous lung needle biopsy specimens for successful molecular testing in patients with advanced NSCLC.

METHODS

This interdisciplinary qualitative study included ten radiologists and four pathologists from academic and community settings across the United States who routinely perform and analyze percutaneous lung needle biopsies. Participants underwent semi-structured one-on-one interviews (Phase 1). Interview questionnaires were constructed based on a literature review of key lines of inquiry and conducted by professional market researchers using the theoretical domains framework. Primary barriers to molecular testing were identified using thematic analysis. Subsequently, multidisciplinary focus groups were convened to identify potential solutions (Phase 2).

RESULTS

Four themes emerged as barriers to molecular testing and were matched to the clinical workflow: (1) biopsy request, (2) biopsy procedure, (3) specimen analysis, and (4) communication. The nineteen potential solutions included adding a "checkbox" to indicate molecular testing in the biopsy request, leveraging pre-procedural imaging to guide biopsies, conserving tissue through appropriate allocation strategies and next generation sequencing panels instead of sequential single-gene assays, instituting reflex-molecular testing upon NSCLC diagnosis, tracking and communicating biopsy outcomes at multidisciplinary tumor boards, and improving integration of radiologists and pathologists into oncology care teams.

CONCLUSIONS

Potential solutions exist to increase successful molecular testing of lung needle biopsy specimens in patients with advanced NSCLC.

Helical CT versus intermittent CT fluoroscopic guidance for musculoskeletal needle biopsies: impact on radiation exposure, procedure time, diagnostic yield, and adverse events

OBJECTIVE

Image-guided percutaneous needle biopsies are essential in the workup of musculoskeletal (MSK) lesions. While helical CT (HCT) is well established, intermittent CT fluoroscopy (iCTF) is an increasingly used alternative. The purpose of this study is to establish whether differences in subject radiation exposure, procedure time, yield, or adverse events exist between HCT and iCTF guidance.

MATERIALS AND METHODS

This retrospective cohort study included consecutive MSK needle biopsies performed on a single-CT scanner over a 12-month period at a tertiary academic center. Subject demographics, radiation dose, and outcomes were abstracted from the medical record. Comparisons between the two cohorts were performed using Student's t-test for continuous data and using Fisher's exact test for categorical data and a two-tailed p value less than 0.05 was considered significant.

RESULTS

Two hundred sixteen adults (115 (53.2%) females) with a mean age of 58.8 ± 18.4 years, underwent 216 biopsies (109 (50.5%) HCT guided, 107 (49.5%) iCTF guided) between June 2017 and June 2018. Dose-length product (DLP) and volume CT dose index (CTDIvol) were significantly higher for the HCT cohort (HCT 698.9 ± 400.8 mGycm vs iCTF 312.8 ± 170.8 mGycm; p < 0.005 and HCT 19.1 mGy ± 8.8 vs iCTF 6.9 mGy ± 1.5, p < 0.001). No significant difference in diagnostic yield, procedure time, or adverse event rate was identified.

CONCLUSION

For CT-guided MSK needle biopsies, iCTF decreases subject radiation dose compared to HCT without negatively affecting outcomes. iCTF should be strongly considered by radiologists performing MSK biopsies given the reduced patient radiation exposure.

Magnetic Resonance Imaging for Guidance and Follow-up of Thoracic Needle Biopsies and Thermal Ablations

Magnetic resonance imaging (MRI) is used for the guidance and follow-up of percutaneous minimally invasive interventions in many body parts. In the thorax, computed tomography (CT) is currently the most used imaging modality for the guidance and follow-up of needle biopsies and thermal ablations. Compared with CT, MRI provides excellent soft tissue contrast, lacks ionizing radiation, and allows functional imaging. The role of MRI is limited in the thorax due to the low hydrogen proton density and many air-tissue interfaces of the lung, as well as respiratory and cardiac motion. Here, we review the current experience of MR-guided thoracic needle biopsies and of MR-guided thermal ablations targeting lesions in the lung, mediastinum, and the chest wall. We provide an overview of MR-compatible biopsy needles and ablation devices. We detail relevant MRI sequences and their relative advantages and disadvantages for procedural guidance, assessment of complications, and long-term follow-up. We compare the advantages and disadvantages of CT and MR for thoracic interventions and identify areas in need of improvement and additional research.

Role of Image-Guided Percutaneous Needle Biopsy in the Age of Precision Medicine

PURPOSE OF REVIEW

With the remarkable progress in cancer precision medicine, the demand for biopsy has been increasing, and the role of biopsy has been changing. In this review, we discuss the current state and recent advances in the role of image-guided percutaneous needle biopsy (PNB) in facilitating precision medicine.

RECENT FINDINGS

Biopsies are useful not only in the diagnosis of cancer and histological sub-type but also in the analysis of its molecular characteristics for targeted treatments. PNB specimens have been shown to provide high DNA yields for genomic analysis. Liquid biopsy is an emerging technology but is under development; therefore, PNB is the current standard of practice and is performed complimentarily with liquid biopsy. In the age of precision medicine, interventional oncologists play a key role in optimal tissue collection for adequate genomic analysis. Effective PNB may improve its diagnostic utility and help optimize precision medicine.

Image-Guided Percutaneous Lung Needle Biopsy: How we do it

Image-guided lung needle biopsy allows for minimally invasive diagnosis of lung pathology. In the setting of suspected malignancy, the biopsy not only confirms the diagnosis but also allows for molecular profiling, a requisite for tailored systemic therapy. Needle biopsy can also characterize non-neoplastic entities such as infections not responding to treatment and other inflammatory processes. A successful and safe lung needle biopsy starts with lesion and patient selection and careful pre-procedural evaluation. Here we review the indications and contraindications, diagnostic alternatives, approach planning and sequential procedural steps with the goal of maximizing both yield and patient safety. We discuss technical tips for preventing complications such as pleural anesthesia, the saline seal, the blood patch, the banana bend, hydro dissection, and the rapid needle out/patient rollover maneuver. We also review how to manage complications, avoid non-diagnostic biopsies, and provide recommendations for post-procedural observation and imaging follow-up.