Cytologic evaluation of image-guided fine needle aspiration biopsies via robotic microscopy: A validation study

Selective deployment of dynamic telecytology for rapid evaluation of cytology smears: assessment of workflow processes and role of cytopathology fellows as on-site operators

INTRODUCTION

The deployment of telecytology (TC) requires a substantial investment of financial and human resources. To offset the high demand for rapid on-site evaluation, we performed a limited deployment of dynamic TC and have detailed the workflow processes and the role of trainees.

MATERIALS AND METHODS

TC systems were installed in radiology suites with a high volume of cases. Validation was performed using retrospective and prospective cases. Cytotechnologists and cytopathology fellows were the operators of the instrument. TC malignant and benign diagnoses were correlated with the final sign-out diagnoses.

RESULTS

Of the 120 cases, 50 (41.6%) were fine needle aspirations and 70 (58.3%) were touch imprint smears of core biopsy specimens. The cytotechnologists were the operators for 34 cases (28.3%) and cytology fellows for 86 cases (71.6%). Adequacy concordance with the final diagnosis was 100% and 98.5% in the retrospective and prospective cases, respectively. In the prospective cases, concordance of TC with the final diagnosis of malignancy was 42 of 45 (93.3%), with 2 of 45 (4.4%) discordant and a downgrade rate of 2.7%. For the benign diagnoses, the concordance was 90%. For the malignant diagnoses, the sensitivity of TC was 97.67% (95% confidence interval [CI], 87.71 to 99.94%; specificity, 81.82%; 95% CI, 48.22% to 97.72%). The positive predictive value was 95.45% (95% CI, 85.69% to 98.66%), the negative predictive value was 90.00% (95% CI, 55.98% to 98.45%), and the accuracy was 94.44% (95% CI, 84.61% to 98.84%).

CONCLUSIONS

TC can be deployed in a limited fashion as an option for cytopathologists to offset the high demand for rapid on-site evaluations. Trainee participation in TC service is important for building confidence and honing their cytology skills.

Telepathology: An update on applications, latest advances, and current status in Indian scenario

Pathologists have been using their tool of trade, "the microscope," since the early 17^th century, but now diagnostic pathology or tissue-based diagnosis is characterized by its high specificity and sensitivity. Technological telecommunication advances have revolutionized the face of medicine, and in pursuit of better health-care delivery, telepathology has emerged. Telepathology is the practice of diagnostic pathology performed at a distance, with images viewed on a video monitor rather than directly through the (light) microscope. This article aims to provide an overview of the field, including specific applications, practice, benefits, limitations, regulatory issues, latest advances, and a perspective on the current status of telepathology in Indian scenario based on literature review.

Whole slide imaging compared with light microscopy for primary diagnosis in surgical neuropathology: a validation study

BACKGROUND

Digital pathology practice is rapidly gaining popularity among practicing anatomic pathologists. Acceptance is higher among the newer generation of pathologists who are willing to adapt to this new diagnostic method due to the advantages offered by whole slide imaging (WSI) compared to traditional light microscopy (TLM). We performed this validation study because we plan to implement the WSI system for diagnostic services.

OBJECTIVES

Determine the feasibility of using digital pathology for diagnostic services by assessing the equivalency of WSI and TLM.

DESIGN

A laboratory-based cross-sectional study.

SETTING

Central laboratory at a tertiary health care center.

MATERIALS AND METHODS

Four practicing surgical pathologists participated in this study. Each pathologist blindly reviewed 60 surgical neuropathology cases with a minimum 8-week washout-period between the two diagnostic modalities (WSI vs. TLM). Intraobserver concordance rates between WSI and TLM diagnoses as compared to the original diagnosis were calculated.

MAIN OUTCOME MEASURES

Overall intraobserver concordance rates between each diagnostic method (WSI and TLM) and original diagnosis.

SAMPLE SIZE

60 in-house surgical neuropathology cases.

RESULTS

The overall intraobserver concordance rate between TLM and original diagnosis was 86.3% (range 76.7%-91.7%) versus 80.8% for WSI (range 68.3%-88.3%). These findings are suggestive of the superiority of TLM, but the Fleiss' Kappa statistic indicated that the two methods are equivalent, despite the low level of the K value.

CONCLUSION

WSI is not inferior to the light microscopy and is feasible for primary diagnosis in surgical neuropathology. However, to ensure the best results, only formally trained neuropathologists should handle the digital neuropathology service.

LIMITATIONS

Only one diagnostic slide per case rather than the whole set of slides, sample size was relatively small, and there was an insufficient number of participating neuropathologists.

CONFLICT OF INTEREST

None.

Rapid on-site evaluation using telecytology: A major cancer center experience

BACKGROUND

Rapid on-site evaluation (ROSE) with cytology preparations plays a critical role in minimally invasive procedures. The time spent by a pathologist performing ROSE is unpredictable and could be used for more cost-effective activities. The solution encountered by several institutions to address this issue is the use of telecytology (TC). This study analyzes the experience of using telecytology for ROSE in a major cancer center over a period of over 2 years.

METHODS

A retrospective analysis of all remote TC evaluations for adequacy on fine needle aspiration (FNA) and touch preparations (TP) of core biopsies (CB) performed at a major cancer center was performed. The preliminary adequacy assessment was then compared to the adequacy assessment at final diagnosis.

RESULTS

A total of 12 949 adequacy assessments were analyzed. The most common sites biopsied in our institution were lymph node, lung, and liver. There were 7725 adequacy assessments for CB (59.7%), while adequacy assessment for FNA specimens represented 40.3% (n = 5224) of the total number of specimens evaluated by ROSE. Perfect concordance between initial adequacy assessment and the adequacy assessment at final cytologic diagnosis was 93% (12 049/12 949). The final diagnosis adequacy upgrade rate was 6.7% (n = 863), and the adequacy downgrade (a specimen considered adequate on-site that was determined to be nondiagnostic on final examination) was 0.3% (n = 37).

CONCLUSIONS

TC can be easily implemented with the current technologies available. It is cost-effective and allows for better patient care with a more efficient use of the pathologist's time and laboratory resources.

Digital Applications in Cytopathology: Problems, Rationalizations, and Alternative Approaches

OBJECTIVE

The aim of this work was to raise awareness of problems using digital applications for examining, teaching, and applying telecytology at King Abdulaziz Medical City (KAMC), Riyadh, Saudi Arabia; University of Nebraska Medical Center (UNMC), Omaha, NE, USA; and University of Pittsburgh Medical Center (UPMC), Pittsburgh, PA, USA. The objective was to rationalize problems and propose alternative digital approaches.

STUDY DESIGN

We sought to identify solutions to improve the following: (a) interpretive examination scores at KAMC for complex cytological templates (i.e., high-grade squamous intraepithelial lesions [HSIL]) when using static digital images (SDI) of cells in regions of interest (ROI); (b) visualization of cells in 3D clusters when teaching at UNMC using 2D and 3D whole-slide imaging (WSI); and (c) visualization of cells through streaming telecytology at UPMC.

RESULTS

Composite SDI (CSDI) improved test scores for complex interpretations (i.e., HSIL) by converging diagnostic criteria from multiple ROI. Multiplane focusing through z-stacked WSI facilitated the teaching of cytological entities characterized by 3D cell clusters and consultative telecytology through robotic cell analysis.

CONCLUSIONS

Adequately visualized cytomorphology and multiplane focusing are essential for virtual cytopathology examinations, teaching, or consultative telecytology. Visualization of diagnostic criteria through 2D or 3D imaging is critical. Panoptiq panoramic WSI with integrated z-stacked video clips enables optimal applied telecytology.

Successful Secure High-definition Streaming Telecytology for Remote Cytologic Evaluation

BACKGROUND

The use of minimally invasive procedures to obtain material for diagnostic purposes has become more prevalent in recent years. As such, there is increased demand for immediate cytologic adequacy assessment of minimally invasive procedures. The array of different locations in which rapid on-site evaluation (ROSE) is expected requires an ever-increasing number of cytology personnel to provide support for adequacy assessment. In our study, we describe the implementation process of a telecytology (TC) system in a high case volume setting and evaluate the performance of this activity.

METHODS

We performed retrospectively an analysis of all consecutive remote TC ROSE evaluations obtained for 15 months. The specimens were evaluated using a TC system. The ROSE adequacy assessment obtained at the time of the procedure was compared to the final cytopathologist-rendered adequacy assessment when all the material was available for review, including the alcohol-fixed preparations.

RESULTS

A total of 8106 distinct cases were analyzed. TC-assisted preliminary adequacy assessment was highly concordant with the final cytopathologist-rendered adequacy assessment. Perfect concordance or accuracy was at 93.1% (7547/8106). The adequacy upgrade rate (inadequate specimen became adequate) was 6.8% (551/8106), and the initial adequacy downgrade (adequate specimen became inadequate) was <0.1% (8/8106).

CONCLUSIONS

The TC outcome demonstrates high concordance between the initial adequacy assessment and final cytopathologist-rendered adequacy assessment. Adequacy upgrades were minor but, more importantly, our results demonstrate a minimal adequacy downgrade. The process implemented effectively eliminated the need for an attending pathologist to be physically present onsite during a biopsy procedure.

Robotic Telecytology for Remote Cytologic Evaluation without an On-site Cytotechnologist or Cytopathologist: An Active Quality Assessment and Experience of Over 400 Cases

BACKGROUND

The first satellite center to offer interventional radiology procedures at Memorial Sloan Kettering Cancer Center opened in October 2014. Two of the procedures offered, fine needle aspirations and core biopsies, required a rapid on-site cytologic evaluation of smears and biopsy touch imprints for cellular content and adequacy. The volume and frequency of such evaluations did not justify hiring on-site cytotechnologists, and therefore, a dynamic robotic telecytology (TC) solution was created. In this article, we provide data on our experience with this active implementation. Sakura VisionTek was selected as our robotic TC solution.

METHODS

A retrospective analysis of all TC evaluations from this satellite site was performed. Information was collected on demographics, lesion location, imaging modality; a comparison of TC-assisted adequacy with final adequacy was also conducted.

RESULTS

An analysis of 439 cases was performed over a period of 23 months with perfect correlation in 92.7% (407/439) of the cases. An adequacy upgrade (inadequate specimen becomes adequate) in 6.6% (29/439) of the cases. An adequacy downgrade (adequate specimen becomes inadequate), is near zero at 0.7% (3/439) of the cases.

CONCLUSIONS

Dynamic robotic TC is effective for immediate evaluations performed without on-site cytotechnology staff. The overall intent of this article is to present data and concordance rates as outcome metrics. Thus far, such outcome metrics have exceeded our expectations. Our TC implementation shows high, perfect concordance. Adequacy upgrades are minor but more relevant and impressive is a near zero adequacy downgrade. Our full implementation has been so successful that plans are in place for configurations at future satellite sites.

Digital cytopathology

The advancements in the fields of technology and networking have revolutionized the world including the fields of medicine and dentistry. Telemedicine and its various branches provide a broad platform to medical professionals for consultations and investigations and can also act as a valuable educational aid. This review highlights the components, methods employed, clinical applications, advantages, disadvantages of telepathology and telecytology.

Validation of a novel robotic telepathology platform for neuropathology intraoperative touch preparations

Background:

Robotic telepathology (RT) allows a remote pathologist to control and view a glass slide over the internet. This technology has been demonstrated to be effective on several platforms, but we present the first report on the validation of RT using the iScan Coreo Au whole slide imaging scanner.

Methods:

One intraoperative touch preparation slide from each of 100 cases were examined twice (200 total cases) using glass slides and RT, with a 3 week washout period between viewings, on two different scanners at two remote sites. This included 75 consecutive neuropathology cases and 25 consecutive general surgical pathology cases. Interpretations were compared using intraobserver variability.

Results:

Of the 200 total cases, one failed on RT. There were 47 total interpretive variances. Most of these were the result of less specific interpretations or an inability to identify scant diagnostic material on RT. Nine interpretive variances had potentially significant clinical implications (4.5%). Using the final diagnosis as a basis for comparison to evaluate these nine cases, three RT interpretations and three glass slide interpretations were considered to be discrepant. In the other three cases, both modalities were discrepant. This distribution of discrepancies indicates that underlying case difficulty, not the RT technology, probably accounts for these major variances. For the subset of 68 neoplastic neuropathology cases, the unweighted kappa of agreement between glass slides and RT was 0.68 (good agreement). RT took 225 s on average versus only 71 s per glass slide.

Conclusions:

This validation demonstrates that RT using the iScan Coreo Au system is a reasonable method for supplying remote neuropathology expertise for the intraoperative interpretation of touch preparations, but is limited by the slowness of the robotics, crude focusing, and the challenge of determining where to examine the slide using small thumbnail images.

Thyroid fine-needle aspiration cytology: is there a place to virtual cytology?

Telecytology has been used for education, training, and consultation. Cytological studies from gynecological, nongynecological and fine-needle aspiration cytology (FNAC) specimens (including studies of thyroid FNAC) analyzed the diagnostic accuracy and reproducibility of telecytology-based predominantly on static digital images. The aim of this study was to evaluate the diagnostic reproducibility of virtual cytology by measuring intraobserver and interobserver agreements among two cytopathologists, using the Bethesda System for Reporting Thyroid Cytopathology (BSRTC) nomenclature. 502 glass slides from 222 cases of thyroid FNAC were retrieved and scanned by a high-resolution scanner generating whole slides images (virtual cytology). Conventional and virtual cytology were analyzed by a skilled cytopathologist and the intraobserver agreement rate was 77.5% with the corresponding κ value of 0.54, suggesting a moderate agreement between both methods. A second cytopathologist analyzed the same slides only by virtual cytology and the interobserver agreement rate was 80.2% with the corresponding κ value of 0.57, suggesting a moderate agreement between both cytopathologists. The virtual cytology resulted in a higher proportion of aspirates classified as nondiagnostic (20.3 and 14.9% for the first and second cytopathologist, respectively) as compared to conventional cytology (8.1%). Regarding specific diagnostic categories as defined by the BSRTC nomenclature, the follicular lesion of undetermined significance category presented the lowest concordance rates, corresponding to 5.9% intraobserver agreement and no (0.0%) interobserver agreement. We suggest that virtual cytology can be an alternative to conventional cytology in assessment of thyroid FNAC specimens, but nondiagnostic aspirates obtained by virtual cytology should be reassessed by conventional cytology.

Experience with multimodality telepathology at the University of Pittsburgh Medical Center

Several modes of telepathology exist including static (store-and-forward), dynamic (live video streaming or robotic microscopy), and hybrid technology involving whole slide imaging (WSI). Telepathology has been employed at the University of Pittsburgh Medical Center (UPMC) for over a decade at local, national, and international sites. All modes of telepathology have been successfully utilized to exploit our institutions subspecialty expertise and to compete for pathology services. This article discusses the experience garnered at UPMC with each of these teleconsultation methods. Static and WSI telepathology systems have been utilized for many years in transplant pathology using a private network and client-server architecture. Only minor clinically significant differences of opinion were documented. In hematopathology, the CellaVision^® system is used to transmit, via email, static images of blood cells in peripheral blood smears for remote interpretation. While live video streaming has remained the mode of choice for providing immediate adequacy assessment of cytology specimens by telecytology, other methods such as robotic microscopy have been validated and shown to be effective. Robotic telepathology has been extensively used to remotely interpret intra-operative neuropathology consultations (frozen sections). Adoption of newer technology and increased pathologist experience has improved accuracy and deferral rates in teleneuropathology. A digital pathology consultation portal (https://pathconsult.upmc.com/) was recently created at our institution to facilitate digital pathology second opinion consults, especially for WSI. The success of this web-based tool is the ability to handle vendor agnostic, large image files of digitized slides, and ongoing user-friendly customization for clients and teleconsultants. It is evident that the practice of telepathology at our institution has evolved in concert with advances in technology and user experience. Early and continued adoption of telepathology has promoted additional digital pathology resources that are now being leveraged for other clinical, educational, and research purposes.

Telecytology: Clinical applications, current challenges, and future benefits

Telecytology is the interpretation of cytology material at a distance using digital images. For more than a decade, pioneering efforts to introduce telecytology into clinical practice have been reported. A Medline search for "telecytology" and "cytology" reveals a voluminous literature, though much of what has been published to date is based on technologies that are rapidly becoming obsolete. The technological limitations of previous techniques, including the transmission of static digital images and dynamic streaming images, have limited telecytology to minor niches. The primary problem with these technologies is that the remote viewer can only see a small fraction of the material on the original slides, introducing the possibility of diagnostic error based not only on image quality but also on image selection. Remote robotic microscopy offers one possible solution to this problem, but to date has found limited acceptance, principally attributable to slow operating times. Whole slide imaging seems to be a much more promising solution, though cytology-specific literature regarding its use is still scant. The advent of whole slide imaging opens up new possibilities for telecytology by enabling high-quality images of entire cytology specimens to be available to anyone, anywhere via the Internet. Although challenges remain, especially with regard to capturing the full microscopy experience including multiple planes of focus and sharp high-powered images, rapidly advancing technology promises to overcome these limitations. Increasing application of whole slide imaging technology in surgical pathology will undoubtedly also increase its application to cytology due to the increasing affordability and practicality of the equipment as it serves a larger number of useful roles within a pathology department. The current and expanding applications of telecytology for clinical practice, education, quality assurance, and testing will be reviewed.

Digital imaging in cytopathology

Rapid advances are occurring in the field of cytopathology, particularly in the field of digital imaging. Today, digital images are used in a variety of settings including education (E-education), as a substitute to multiheaded sessions, multisite conferences, publications, cytopathology web pages, cytology proficiency testing, telecytology, consultation through telecytology, and automated screening of Pap test slides. The accessibility provided by digital imaging in cytopathology can improve the quality and efficiency of cytopathology services, primarily by getting the expert cytopathologist to remotely look at the slide. This improved accessibility saves time and alleviates the need to ship slides, wait for glass slides, or transport pathologists. Whole slide imaging (WSI) is a digital imaging modality that uses computerized technology to scan and convert pathology and cytology glass slides into digital images (digital slides) that can be viewed remotely on a workstation using viewing software. In spite of the many advances, challenges remain such as the expensive initial set-up costs, workflow interruption, length of time to scan whole slides, large storage size for WSI, bandwidth restrictions, undefined legal implications, professional reluctance, and lack of standardization in the imaging process.