Navigate biopsy with ultrasound under augmented reality device: Towards higher system performance

PURPOSE

Biopsies play a crucial role in determining the classification and staging of tumors. Ultrasound is frequently used in this procedure to provide real-time anatomical information. Using augmented reality (AR), surgeons can visualize ultrasound data and spatial navigation information seamlessly integrated with real tissues. This innovation facilitates faster and more precise biopsy operations.

METHODS

We have developed an augmented reality biopsy navigation system characterized by low display latency and high accuracy. Ultrasound data is initially read by an image capture card and streamed to Unity via net communication. In Unity, navigation information is rendered and transmitted to the HoloLens 2 device using holographic remoting. Concurrently, a retro-reflective tool tracking method is implemented on the HoloLens 2, enabling the simultaneous tracking of the ultrasound probe and biopsy needle. Distinct navigation information is provided during in-plane and out-of-plane punctuation. To evaluate the effectiveness of our system, we conducted a study involving ten participants, assessing puncture accuracy and biopsy time in comparison to traditional methods.

RESULTS

Ultrasound image was streamed from the ultrasound device to augmented reality headset with 122.49±11.61ms latency, while only 16.22±11.25ms was taken after data acquisition from image capture card. Navigation accuracy reached 1.23±0.68mm in the image plane and 0.95±0.70mm outside the image plane, within a depth range of 200 millimeters. Remarkably, the utilization of our system led to 98% and 95% success rate in out-of-plane and in-plane biopsy, among ten participants with little ultrasound experience.

CONCLUSION

To sum up, this paper introduces an AR-based ultrasound biopsy navigation system characterized by high navigation accuracy and minimal latency. The system provides distinct visualization contents during in-plane and out-of-plane operations according to their different characteristics. Use case study in this paper proved that our system can help young surgeons perform biopsy faster and more accurately.

Detection of Circulating Tumor Cells in Patients with Small Choroidal Melanocytic Lesions

PURPOSE

To determine the presence of circulating tumor cells (CTCs) in patients with indeterminate small choroidal melanocytic lesions (SCMLs).

DESIGN

Retrospective case series.

PARTICIPANTS

Forty-seven patients with choroidal melanocytic lesions 2.5 mm or less in tumor thickness and ≤ 10 mm in largest basal diameter (LBD).

METHODS

Blood samples were analyzed for CTCs and the presence of monosomy-3 (M3) in CTCs. Tissue biopsy was performed in the patients who were CTC-positive (pCTC).

MAIN OUTCOME MEASURES

Presence and M3 status of the CTCs with regard to the clinical characteristics and results from tissue biopsy.

RESULTS

Median thickness of all (n = 47) lesions was 1.1 mm (range: 0.2-2.5 mm), and LBD was 5.6 mm (range: 2.0-10.0 mm). Circulating tumor cells were found in 25 patients (n = 25). This group was classified as pCTC and compared with the CTC-negative (nCTC) group consisting of 22 patients (n = 22). Median tumor dimensions in the pCTC versus the nCTC group were 1.6 mm (range: 0.6-2.5 mm) versus 0.5 mm (range: 0.2-2.5 mm) for thickness and 6.6 mm (range: 4.1-10.0 mm) versus 4.0 mm (range: 2.0-8.0 mm) for LBD, respectively. Both LBD and thickness were positively associated (P < 0.001) with the presence of CTC. Compared with the nCTC group, a higher percentage of the pCTC group exhibited LBD > 5 mm (36% vs. 88%), subretinal fluid (9.1% vs. 56%), orange pigment (4.5% vs. 60%), sonographic hollowness (9.1% vs. 60%), and the presence of multiple risk factors (0% vs. 68% for ≥3 factors) with P < 0.001 for all parameters. No significant difference was detected in the clinical parameters of the patients who had disomy-3 (D3) (n = 7) versus M3 (n = 17) in their CTC. The tissue biopsy confirmed the uveal melanoma (UM) in 22 of the 25 pCTC patients (88%), whereas no conclusive diagnosis could be determined in the remaining 3 cases because of insufficient or invalid material.

CONCLUSIONS

We report compelling evidence for the potential of liquid biopsy as an additional tool to screen SCMLs for malignancy. These findings pave the way toward the implementation of liquid biopsy to detect small UM and monitor melanocytic lesions.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Concomitant, Single Burr Hole Endoscopic Third Ventriculostomy and Tumor Biopsy for Pineal Lesions: Feasibility, Safety, and Benefits

Obtaining a prompt diagnosis, avoiding indwelling ventriculoperitoneal shunt, and enhancing the predictive value of pathologic examinations are only some of the advantages conferred by a simultaneous third ventriculostomy and tumor biopsy in patients with pineal region tumors. The objective of this study was to retrospectively search the literature on concomitant, single burr hole endoscopic third ventriculostomy (ETV) and tumor biopsy (TB) for pineal region tumors and to analyze the feasibility, surgical safety, and benefits of these 2 combined procedures. Consequently, a comprehensive, systematic literature search was performed in compliance with the updated PRISMA 2020 guidelines within electronic databases MEDLINE/PubMed, EMBASE, PLOS, and Cochrane Library. Statistical analysis was performed with IBM SPSS 28.0.1.1(14), using Kendall's and Spearman's tests, with a P < 0.05 considered significant. A total of 25 studies were selected and included in this review, for a total of 368 patients (mean age 20.6 years; range 1-86 years; SD 17.5). More than two-thirds of the procedures were operated with a rigid endoscope and 27.6% were performed with either a flexible endoscope, a combination of the 2, or not otherwise specified. Germinoma represented the most frequent diagnosis (20.1%) followed by astrocytoma (12.9%) and pineocytoma (9.9%). The single-entry approach allowed a correct histologic diagnosis in 88.7% of the examined cases. Summing up, concomitant ETV and TB represent a valuable option for the management of non-communicating hydrocephalus and the initial assessment of pineal region tumors. The histologic confirmation rate was 88.7% in the examined cohort, with only 10% of the biopsies yielding inconclusive results.

Increasing Biomarker Guidance in the Treatment of Urothelial Carcinoma: Systematic Review of International Clinical Trials

PURPOSE

Precision oncology requires biomarker testing from tumor tissue for clinical decision-making and selection of targeted therapies. We systematically evaluated the role of tissue biomarker testing within interventional clinical trials for locally advanced and metastatic urothelial carcinoma (UC).

METHODS

A systematic search within the publicly available ClinicalTrials.gov database was performed for the period 1995 to January 2020. We searched for all interventional studies on systemic treatments for advanced UC. Two investigators independently screened the records and extracted the data for statistical analyses.

RESULTS

We included 356 studies out of 827 initial records in the final analysis. The overall number of interventional trials in UC patients significantly increased during the past 25 years. Forty-three studies (12.1%) required specific biomarker testing as a prerequisite for inclusion. Of the remaining 313 trials, explorative biomarkers of interest were studied in 83 studies (23.3%). In trials with obligate biomarker testing as a precondition for study inclusion, only 3 studies (7%) required an actual fresh pretreatment biopsy, while the majority of studies did not state any tissue requirements (55.8%) or accepted archival tissue samples (37.3%). Among studies without biomarker prerequisites, freshly obtained tissue samples were required in 16.3% of studies evaluating immune checkpoint inhibition and 5.7% evaluating targeted therapy. The collection of archival tissue was allowed in 67.4% and 20% of studies evaluating immune checkpoint inhibitors and targeted therapies, respectively.

CONCLUSION

There has been an increase in the number of studies using biomarker-guided interventions for the treatment of advanced UC over the past 25 years. Studies investigating druggable targets in actual UC biopsies immediately before treatment are still rare. Standardized criteria for tissue-based biomarker testing may further accelerate personalized treatment of patients with advanced UC.

Diagnostics and prognostic evaluation in renal cell tumors: the German S3 guidelines recommendations

The German guidelines on renal cell carcinoma (RCC) have been developed at highest level of evidence based on systematic literature review. In this paper, we are presenting the current recommendations on diagnostics including preoperative imaging and imaging for stage evaluation as well as histopathological classification. The role of tumor biopsy is further discussed. In addition, different prognostic scores and the status of biomarkers in RCC are critically evaluated.

Carcinoma of unknown primary origin with isolated adrenal metastasis: a report of two cases

The adrenal glands are one of the most common sites of malignant tumor metastasis. However, metastatic adrenal carcinoma of unknown primary origin with localized adrenal gland involvement is an extremely rare condition. Herein, we reported two cases of carcinoma of unknown primary origin with isolated adrenal metastasis. In the first case, back pain was the trigger; while in the second case, the triggers were low fever and weight loss. Metabolic abnormalities such as hypertension and obesity were not detected in either case. Neither patient had relevant previous medical histories, including malignancy. However, both had a long-term history of smoking. Systemic imaging studies revealed only adrenal tumors and surrounding lesions. Primary adrenocortical carcinoma was initially suspected, and chemotherapy including mitotane was considered. However, due to difficulty in complete resection of the tumor, core needle tumor biopsies were performed. Histopathological examination of biopsy specimens led to the diagnosis of carcinoma of unknown primary origin with isolated adrenal metastasis. In both cases, additional laboratory testing showed high levels of serum squamous cell carcinoma-related antigen and serum cytokeratin fragment. Malignant lesions confined to the adrenal glands are rare. As in our cases, it could be occasionally difficult to differentiate non-functioning primary adrenocortical carcinoma from metastatic adrenal carcinoma of unknown primary origin localized to the adrenal gland. If the lesion is unresectable and there are elevated levels of several tumor markers with no apparent hormonal excess, core needle tumor biopsy should be considered to differentiate the primary tumor from the metastatic tumor.

The morbidity of open tumor biopsy for intraabdominal neoplasms in pediatric patients

PURPOSE

Tumor biopsy is often essential for diagnosis and management of intraabdominal neoplasms found in children. Open surgical biopsy is the traditional approach used to obtain an adequate tissue sample to guide further therapy, but image-guided percutaneous core-needle biopsy is being used more often due to concerns about the morbidity of open biopsy. We used a national database to evaluate the morbidity associated with open intraabdominal tumor biopsy.

METHODS

We identified all patients undergoing laparotomy with tumor biopsy in the National Surgical Quality Improvement Project-Pediatric (NSQIP-P) database from 2012 to 2018 and measured the frequency of complications in the 30 days postoperatively. We tested associations between patient characteristics and outcomes to identify risk factors for complications.

RESULTS

We identified 454 patients undergoing laparotomy for biopsy of an intraabdominal neoplasm. Median postoperative hospital stay was 7 days (IQR 4-12) and operative time was 117 min (IQR 84-172). The overall complication rate was 12.1%, with post-operative infection (6%) and bleeding (4.2%) being the most common complications. Several patient characteristics were associated with bleeding, but the only significant association on multivariable analysis was underlying hematologic disorder.

CONCLUSION

Open abdominal surgery for pediatric intraabdominal tumor biopsy is accompanied by significant morbidity. Postoperative infection was the most common complication, which can delay initiation of further therapy, especially chemotherapy. These findings support the need to prospectively compare percutaneous image-guided core-needle biopsy to open biopsy as a way to minimize risk and optimize outcomes for this vulnerable population.

Soft Urinary Bladder Phantom for Endoscopic Training

Bladder cancer (BC) is the main disease in the urinary tract with a high recurrence rate and it is diagnosed by cystoscopy (CY). To train the CY procedures, a realistic bladder phantom with correct anatomy and physiological properties is highly required. Here, we report a soft bladder phantom (FlexBlad) that mimics many important features of a human bladder. Under filling, it shows a large volume expansion of more than 300% with a tunable compliance in the range of 12.2 ± 2.8 - 32.7 ± 5.4 mL cmH2O-1 by engineering the thickness of the bladder wall. By 3D printing and multi-step molding, detailed anatomical structures are represented on the inner bladder wall, including sub-millimeter blood vessels and reconfigurable bladder tumors. Endoscopic inspection and tumor biopsy were successfully performed. A multi-center study was carried out, where two groups of urologists with different experience levels executed consecutive CYs in the phantom and filled in questionnaires. The learning curves reveal that the FlexBlad has a positive effect in the endourological training across different skill levels. The statistical results validate the usability of the phantom as a valuable educational tool, and the dynamic feature expands its use as a versatile endoscopic training platform.

Digital PCR detection of EGFR somatic mutations in non-small-cell lung cancer formalin fixed paraffin embedded samples

BACKGROUND

Digital PCR (dPCR) is proposed to replace real time PCR and Sanger sequencing for detection and quantification of rare mutations, frequently unnoticed in the mass of tumoral cells. Screening of endothelial growth factor receptor (EGFR) mutations is mandatory before treatment with EGFR-targeted therapy with small-molecule tyrosine kinase inhibitors, which has been approved for the treatment of advanced non-small-cell lung cancer (NSCLC).

OBJECTIVE

In order to establish a cost-effective method for detection of mutations, we optimized dPCR identification of EGFR mutations in exons 18-21, and determined dPCR sensitivity, limits of detection (LoD) and quantification (LoQ).

METHODS

For clinical validation, we compared the performance of dPCR and castPCR in 57 NSCL formalin fixed paraffin embedded samples and 10 lung cancer-free formalin fixed paraffin embedded samples.

RESULTS

EGFR mutations DEL19, p.L858R, p.G719X, p.L861Q and p.T790 M were detected by dPCR in 27 samples versus 11 detected by castPCR (p = 0.014). LoD was determined as 100 molecules of DNA/uL and LoQ as 1%. Most of the samples (87%) identified by competitive Allele-Specific TaqMan (castPCR) as wild-type and by dPCR as mutated, presented less than 10% mutated DNA molecules (mean 4.57%). Accuracy of dPCR was 94.44%, as measured with the assay recommended by the College of American Pathologists.

CONCLUSION

These results indicated higher sensibility and specificity of dPCR for screening EGFR mutations in NSCLC biopsies, compared to castPCR.

Pineal region tumors: Long-term results of endoscopic third ventriculostomy and concurrent tumor biopsy with a single entry approach in a series of 64 cases

OBJECTIVES

Endoscopic third ventriculostomy and concurrent biopsy is increasingly used in management of the pineal region tumors. Our objective was to assess the results of single entry approach to surgically manage the tumors of the pineal region.

PATIENTS AND METHODS

A retrospective study was designed, and a series of 64 consecutive patients (31 male, 33 female) with pineal region tumor undergoing endoscopic third ventriculostomy and concurrent biopsy of the tumor was undertaken.

RESULTS

A total of 64 patients underwent simultaneous endoscopic third ventriculostomy and biopsy of the pineal tumors with a single entry approach. A positive initial diagnosis was established in 97% of patients. 5 patients (7%) required the insertion of an external ventricular drain which was removed in all patients after 72 h but in one case (1%) undergoing permanent VP shunt insertion. The postoperative complications were divided into two transient and permanent complications. The transient complications included intraventricular hemorrhage (18%), seizure (1 to two episodes of seizure) (5%), diabetes insipidus (3%) and meningitis (3%) all were successfully managed. The only permanent complication was memory deficits occurred in one patient (1%). There was no mortality rate in current study.

CONCLUSION

The results of this study support the safety and efficacy of endoscopic third ventriculostomy and concurrent biopsy of the pineal region tumors as a less invasive surgical method associated with low morbidity and mortality rate. Our data demonstrated how simultaneous endoscopic third ventriculostomy and biopsy of the pineal region tumors with a single entry approach can produce favorable results.

Developing a dynamic simulator for endoscopic intraventricular surgeries

INTRODUCTION

A novel dynamic simulator brain model with hydrocephalus has been developed for endoscopic intraventricular procedures. Detachable components allow enhancement of the walls of the ventricle by choroid plexus, ependymal veins and the membranous floor of the third ventricle which are derived from cadaveric lab animal tissues to give a lifelike appearance. These can be changed for every exercise. Ventricles are filled with injection of saline to give appropriate transparent medium and connected to a device transmitting pulsations creating conditions similar to live surgeries.

MATERIAL AND METHODS

Thirty-five participants have used this model over the last 1 year and found it to be useful for conducting third ventriculostomy. Further development of the model for septostomy, aqueductoplasty and tumour biopsy has also been recently tested successfully by 12 participants.

CONCLUSION

It is hoped that this simulator model for intraventricular endoscopy is comprehensive as a learning tool in carrying out most of the the surgical procedures currently practised.

Visual-Controlled Endoscopic Biopsy of Paraventricular Intraparenchymal Tumors

OBJECTIVE

Frame-based stereotaxy represents the gold standard for biopsy of deep-seated lesions. Visual control of possible bleeding in these lesions is not possible. Neuroendoscopic biopsy represents an alternative procedure for tissue sampling in deep-seated intraventricular lesions. The authors present a technique for transventricular-navigated endoscopic biopsy of lesions that are located in the paraventricular region.

METHODS

Biopsy of paraventricular pathologies was performed in 6 male and 6 female patients between March 2013 and September 2018. The patient age ranged from 18 to 82 years. All patients underwent a pure endoscopic procedure over a burr hole trepanation supported by frameless navigation of the sedan probe.

RESULTS

Histologic diagnoses were established in all biopsies. In all patients, a direct control of the biopsy area was feasible, and hemostasis could be obtained. In 5 patients, endoscopic third ventriculostomy was performed first due to obstructive hydrocephalus. In 1 patient suffering from obstructive hydrocephalus, a pellucidotomy was performed. In 9 cases, the initial postoperative course was uneventful. Three patients suffered from persistent hydrocephalus and had to be treated with ventriculoperitoneal shunt insertion.

CONCLUSIONS

Endoscopically conducted biopsies with the aid of navigated tracking of the probe represent a possible additional technique in selected paraventricular intraparenchymal pathologies. The endoscopic approach enables the direct visualization of the intraventricular surface and its vessels. In contrast to standard stereotactic biopsy, direct visual control of hemostasis can be obtained even in paraventricular tumors.

New concepts in the diagnosis and management of choroidal metastases

The most frequent site of ocular metastasis is the choroid. The occurrence of choroidal metastases has increased steadily due to the longer survival of metastatic patients and the improvement of diagnostic tools. Fundoscopy, ultrasonography, and fluorescein angiography are now complemented by indocyanine green angiography and optical coherence tomography. Choroidal tumor biopsy may also confirm the metastatic nature of the tumor and help to determine the site of the primary malignancy. There is currently no consensus on the treatment strategy. Most patients have a limited life expectancy and for these complex treatments are generally not recommended. However, recent advances in systemic therapy have significantly improved survival of certain patients who may benefit from an aggressive ocular approach that could preserve vision. Although external beam radiation therapy is the most widely used treatment, more advanced forms of radiotherapy that are associated with fewer side effects can be proposed in select cases. In patients with a shorter life expectancy, systemic therapies such as those targeting oncogenic drivers, or immunotherapy can induce a regression of the choroidal metastases, and may be sufficient to temporarily decrease visual symptoms. However, they often acquire resistance to systemic treatment and ocular relapse usually requires radiotherapy for durable control. Less invasive office-based treatments, such as photodynamic therapy and intravitreal injection of anti-VEGF, may also help to preserve vision while reducing time spent in medical settings for patients in palliative care. The aim of this review is to summarize the current knowledge on choroidal metastases, with emphasis on the most recent findings in epidemiology, pathogenesis, diagnosis and treatment.

Diagnostic utility of core needle biopsy versus open wedge biopsy for pediatric intraabdominal solid tumors: Results of a prospective clinical study

PURPOSE

The best method for diagnosing pediatric nonnephroblastoma solid intraabdominal tumors is unknown. We hypothesized that core needle biopsy (CNB) is noninferior to open wedge biopsy (OWB) for pathologic diagnosis.

METHODS

We prospectively enrolled children aged 1day to 17years with radiographic evidence of nonnephroblastoma solid intraabdominal tumors scheduled for OWB from 5/2013 to 12/2015 at a single institution. Four 16-gauge CNBs were obtained, followed by OWB. Two pathologists independently reviewed all specimens to determine adequacy for diagnosis.

RESULTS

Fourteen patients enrolled, 57% male, with an average age of 4years (range 7days to 16years). Both pathologists agreed OWB was completely sufficient for diagnosis in 13 patients (93%), compared to 4 patients for CNB (29%: Burkitt lymphoma, adrenocortical tumor, inflammatory myofibroblastic tumor, p=0.001, δ=-0.64±0.27, 95% CI). In 6 patients (43%), CNB was incompletely diagnostic according to at least one pathologist (neuroblastoma, hepatoblastoma). In 4 patients (29%), both pathologists determined that CNB was nondiagnostic (ganglioneuroblastoma, teratoma, hepatoblastoma, and recurrent neuroblastoma).

CONCLUSIONS

In a prospective clinical study, CNB is inferior to OWB for the pathologic diagnosis of pediatric nonnephroblastoma solid intraabdominal tumors. These data suggest that OWB should generally be performed in these patients.

LEVEL OF EVIDENCE

Study of Diagnostic Test, Level I.

The root causes of pharmacodynamic assay failure

Robust pharmacodynamic assay results are valuable for informing go/no-go decisions about continued development of new anti-cancer agents and for identifying combinations of targeted agents, but often pharmacodynamic results are too incomplete or variable to fulfill this role. Our experience suggests that variable reagent and specimen quality are two major contributors to this problem. Minimizing all potential sources of variability in procedures for specimen collection, processing, and assay measurements is essential for meaningful comparison of pharmacodynamic biomarkers across sample time points. This is especially true in the evaluation of pre- and post-dose tumor biopsies, which suffer from high levels of tumor insufficiency due to variations in biopsy collection techniques and significant specimen heterogeneity within and across patients. Developing methods to assess heterogeneous biopsies is necessary in order to evaluate a majority of tumor biopsies collected for pharmacodynamic biomarker studies. Improved collection devices and standardization of methods are being sought in order to improve the tumor content and quality of tumor biopsies. In terms of reagent variability, we have found that stringent initial reagent qualification and quality control of R&D-grade reagents is critical to minimize lot-to-lot variability and prevent assay failures, especially for clinical pharmacodynamic questions, which often demand assay performance that meets or exceeds clinical diagnostic assay standards. Rigorous reagent specifications and use of appropriate assay quality control methodologies help to ensure consistency between assay runs, laboratories and trials to provide much needed pharmacodynamic insights into the activity of investigational agents.