Telecytopathology for Rapid Preliminary Diagnosis of Ultrasound-Guided Fine-Needle Aspiration of Thyroid Nodules

The use of telecytology for the evaluation of thyroid nodules fine-needle aspiration biopsy specimens: a systematic review

PURPOSE

Fine needle aspiration biopsy (FNAB) is currently the gold standard for diagnosis and treatment of thyroid nodules, but the growing need for anatomic pathology services in small communities is becoming a challenge. Telecytology (TC) is defined as the electronic transmission of cytological digital images, and allows for the collection of samples, primary diagnosis, and other applications without the physical presence of a pathologist. Our aim is to systematically report, summarize, and critically analyze the most up to date applications of TC to thyroid nodules FNAB evaluation.

METHODS

We performed a systematic literature review by searching PubMed, Embase, and Cochrane Library databases. Only studies published in peer-reviewed scientific journals were included. Data were extracted using the PICO framework and critically analyzed. PRISMA guidelines were applied, and the risk of bias in the included studies was assessed using the ROBINS-I tools. The methodological quality was assessed following GRADE criteria.

RESULTS

We included 13 observational studies, resulting in a total of 3856 evaluated FNAB specimens. The majority of studies (63.6%) showed an excellent concordance rate of diagnosis via TC and conventional cytology. TC can be used to perform preliminary assessment of samples with a concordance rate ranging from 74 and 100%, showing a significant reduction of the non-diagnostic rate. Image quality was referred to as perfect or nearly perfect in most cases, regardless of telecytology technique.

CONCLUSION

Telecytology could be a valuable implementation for thyroid FNAB evaluation both for primary diagnosis and preliminary assessment of samples.

American Society of Cytopathology Telecytology validation recommendations for rapid on-site evaluation (ROSE)

Telecytology has multiple applications, including rapid onsite evaluation (ROSE) of fine-needle aspiration (FNA) specimens. It can enhance cytopathology practice by increasing productivity, reducing costs, and providing subspecialty expertise in areas with limited access to a cytopathologist. However, there are currently no specific validation guidelines to ensure safe practice and compliance with regulations. This initiative, promoted by the American Society of Cytopathology (ASC), intends to propose recommendations for telecytology implementation. These recommendations propose that the validation process should include testing of all hardware and software, both separately and as a whole; training of all individuals who will participate in telecytology with regular competency evaluations; a structured approach using retrospective slides with defined diagnoses for validation and prospective cases for verification and quality assurance. Telecytology processes must be integrated into the laboratory's quality management system and benchmarks for discrepancy rates between preliminary and final diagnoses should be established and monitored. Special attention should be paid to minimize discrepancies that downgrade malignant cases to benign (false positive on telecytology). Currently, billing and reimbursement codes for telecytology are not yet available. Once, they are, recommendation of the appropriate usage of these codes would be a part of the recommendations. These proposed guidelines are intended to be a resource for laboratories that are considering implementing telecytology. These recommendations can help to ensure the safe and effective use of telecytology and maximize its benefits for patients.

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.

Rapid On-Site Evaluation With Telecytology Significantly Reduced Unsatisfactory Rates of Thyroid Fine-Needle Aspiration

OBJECTIVES

We evaluated telecytology rapid on-site evaluation (ROSE) for thyroid ultrasound-guided fine-needle aspiration. To the best of our knowledge, this study is the first case-control clinical trial of thyroid telecytology.

METHODS

We introduced on-site ROSE in our institution's thyroid clinic for 6 months, followed by telecytology for 12 months. Our institution's ultrasound clinic, where ROSE is not provided, was used as a control group for each period.

RESULTS

Both groups had similar initial unsatisfactory rates (thyroid clinic: 8.8%; ultrasound clinic: 8.0%) before the study began. The thyroid clinic's unsatisfactory rate was significantly reduced to 1.6% after on-site ROSE (P = .001) and to 3.8% after telecytology ROSE (P = .010), with no significant difference between on-site and telecytology ROSE periods (P > .05). The ultrasound clinic's unsatisfactory rate was unchanged for both periods. Concordance between telecytology ROSE and final adequacy was 97% (κ = 0.699).

CONCLUSIONS

Telecytology ROSE reduces unsatisfactory rates for ultrasound-guided fine-needle aspiration without compromising patient care.

Dynamic Telecytopathology-Guided Rapid On-Site Assessment of Percutaneous Image-Guided Fine-Needle Aspiration of Hepatic Lesions: An Institutional Review of 178 Cases

Background: Rapid on-site evaluation (ROSE) of image-guided fine-needle aspiration (IGFNA) of hepatic lesions is necessary to ensure adequate sample collection and render preliminary diagnosis. We review our experience with utilization of telecytopathology for ROSE of IGFNA of liver lesions. Materials and Methods: Cytotechnologists at a remote site transmitted real-time images of Diff-Quik-stained cytology smears of hepatic lesions obtained using an Olympus DP70 digital camera via Ethernet to a pathologist. All live communications were conducted using the Vocera voice communication system. Preliminary telecytopathology ROSE diagnosis was compared with the final diagnosis for accuracy. Results: ROSE using telecytopathology of IGFNAs of hepatic lesion was performed on a total of 178 cases. Preliminary diagnosis of unsatisfactory, benign, suspicious for malignancy, and positive for malignancy was 2%, 28%, 15%, and 55%, respectively, for telecytopathology. The overall concordance between the preliminary and final cytology diagnoses was 94.4%. Nine of the cases were upgraded to suspicious/malignant final diagnosis contributing to an upgrade rate of 5%. One case with preliminary evaluation of positive for malignancy was downgraded to benign cytology on final diagnosis resulting in a downgrade rate of 0.1%. Conclusion: Utilization of telecytopathology is highly effective and accurate for ROSE of IGFNAs of hepatic lesions and may serve as a substitute for conventional microscopy.

Efficacy of telecytopathology for preliminary assessment of fine-needle aspirations performed at a remote facility

INTRODUCTION

The need for real time anatomic pathology services has grown as healthcare systems, traditionally found at large medical centers, expand into smaller communities. The placement of a pathologist is not cost-, time-, or resource-efficient. Telecytopathology can provide rapid offsite evaluation of cytology tissues. This study evaluated the accuracy rate of rendered preliminary assessments for telecytopathology of ultrasound (US)-guided fine-needle aspirations (FNAs) for an offsite facility by comparing preliminary assessment results with the final diagnosis.

MATERIALS AND METHODS

The pathology database was searched for telecytopathology US-guided FNAs with rapid offsite evaluation performed at a regional care center from August 2014 to June 2016. A total of 674 consecutive US-guided FNAs from 444 patients were obtained. FNA sites included lymph node (345 cases), breast (178 cases), thyroid gland (71 cases), and others (80 cases).

RESULTS

Preliminary assessments of the 674 FNAs were adequate/benign in 275 (41%) cases, adequate/malignant in 182 (27%) cases, adequate/further review needed in 162 (24%) cases, indeterminate/borderline cellularity in 37 (5%) cases, and nondiagnostic in 18 (3%) cases. Final FNA diagnoses rendered included 391 (58%) negative for malignancy, 205 (30%) malignant, 34 (5%) atypical/suspicious for malignancy, 26 (4%) indeterminate cellularity-favor benign, and 18 (3%) nondiagnostic specimens. Concurrent core biopsy was performed in 42 cases and 83 cases were triaged for ancillary studies. The majority (99%) of US-guided FNAs demonstrated concordant preliminary assessments with the final diagnoses. A major discrepancy occurred in 1 case; 5 cases had minor discrepancies.

CONCLUSIONS

Remote facility telecytopathology can be utilized as an accurate modality in guiding appropriate tissue acquisition and final diagnosis.

The Empirical Foundations of Telepathology: Evidence of Feasibility and Intermediate Effects

INTRODUCTION

Telepathology evolved from video microscopy (i.e., "television microscopy") research in the early 1950s to video microscopy used in basic research in the biological sciences to a basic diagnostic tool in telemedicine clinical applications. Its genesis can be traced to pioneering feasibility studies regarding the importance of color and other image-based parameters for rendering diagnoses and a series of studies assessing concordance of virtual slide and light microscopy diagnoses. This article documents the empirical foundations of telepathology.

METHODS

A selective review of the research literature during the past decade (2005-2016) was conducted using robust research design and adequate sample size as criteria for inclusion.

CONCLUSIONS

The evidence regarding feasibility/acceptance of telepathology and related information technology applications has been well documented for several decades. The majority of evidentiary studies focused on intermediate outcomes, as indicated by comparability between telepathology and conventional light microscopy. A consistent trend of concordance between the two modalities was observed in terms of diagnostic accuracy and reliability. Additional benefits include use of telepathology and whole slide imaging for teaching, research, and outreach to resource-limited countries. Challenges still exist, however, in terms of use of telepathology as an effective diagnostic modality in clinical practice.

Rapid on-site evaluation with dynamic telecytopathology for ultrasound-guided fine-needle aspiration of head and neck nonthyroid lesions

BACKGROUND

Rapid on-site evaluation (ROSE) at the time of ultrasound-guided fine-needle aspiration (USGFNA) of head and neck lesion is essential for obtaining adequate samples and providing the preliminary diagnosis. We summarize our experience with ROSE of USGFNA on head and neck nonthyroid lesions using telecytopathology.

MATERIALS AND METHODS

Real-time images of Diff-Quik stained cytology smears were obtained at ultrasound suite with an Olympus DP-70 digital camera attached to an Olympus CX41 microscope, and transmitted via ethernet by a cytotechnologist to a cytopathologist in cytopathology laboratory who rendered a preliminary diagnosis. Live communication was conducted with Vocera voice communication system. The ultrasound suite was located on different floor from the cytopathology laboratory. Accuracy of ROSE via telecytopathology was compared with an equal number of cases that received ROSE, prior to introduction of telecytopathology, via conventional microscopy.

RESULTS

Rapid on-site evaluation was performed on a total of 116 USGFNA of head and neck nonthyroid lesions. The telecytopathology system and conventional microscopy was used to evaluate equal number of cases (58 each). Preliminary diagnoses of benign, atypical/suspicious for malignancy, and positive for malignancy were 72.4%, 17.2% and 10.3% for telecytopathology, and 69.0%, 10.3% and 20.7% for conventional microscopy. None of the cases were deemed unsatisfactory. The overall concordance between the preliminary and final diagnoses was 94.8% for telecytopathology and 98.3% for conventional microscopy and was not statistically significant (P = 0.309). The causes of discordant preliminary and final diagnoses were mainly attributed to availability of cell block and Papanicolaou-stained slides for review or flow cytometry results for lymphoma cases at the time of final sign out.

CONCLUSIONS

Telecytopathology is comparable with conventional microscopy in ROSE of USGFNA of head and neck nonthyroid lesions.

Feasibility of dynamic telecytopathology for rapid on-site evaluation of endobronchial ultrasound-guided transbronchial fine needle aspiration

OBJECTIVE

Rapid on-site evaluation (ROSE) at the time of endobronchial ultrasound-guided transbronchial fine needle aspiration (EBUS-TBFNA) is useful in obtaining adequate samples and providing preliminary diagnosis. We present our experience with ROSE of EBUS-TBFNA using telecytopathology.

MATERIALS AND METHODS

Real-time images of Diff-Quik (Mercedes Medical, Sarasota, FL)-stained cytology smears were obtained with an Olympus (Olympus America, Center Valley, PA) digital camera attached to an Olympus CX41 microscope and transmitted via ethernet by a cytotechnologist to a cytopathologist in a cytopathology laboratory who rendered a preliminary diagnosis while communicating with an on-site cytotechnologist via the Vocera (San Jose, CA) voice communication system. The endoscopy suite was located a block away from the cytopathology laboratory. Accuracy of ROSE via telecytopathology was compared with an equal number of cases that received ROSE, prior to introduction of telecytopathology, via conventional microscopy.

RESULTS

ROSE was performed on a total of 200 EBUS-TBFNAs. The telecytopathology system and conventional microscopy were used to evaluate equal numbers of cases (100 each). Preliminary diagnoses of negative/benign, atypical/suspicious, and positive for malignancy were 58%, 14%, and 24% for telecytopathology and 57%, 10%, and 31% for conventional microscopy. Four percent of telecytopathology cases and 2% of conventional microscopy cases were deemed unsatisfactory at the time of ROSE. The overall concordance between the preliminary and final diagnoses was 96% for telecytopathology and 93% for conventional microscopy. The causes of discordant preliminary and final diagnoses could be mainly attributed to difficulty in distinguishing small cell carcinoma versus reactive lymph node due to crush artifact, atypia related to reactive bronchial epithelial cells, and availability of cell block material and Papanicolaou-stained slides for review at the time of final cytologic sign out.

CONCLUSIONS

Telecytopathology is comparable with conventional microscopy in ROSE of EBUS-TBFNA. It can serve as a valid substitute for conventional microscopy for on-site assessment of EBUS-TBFNA.

Inexpensive telecytology solutions that use the Raspberry Pi and the iPhone

INTRODUCTION

There is currently substantial interest in dynamic telecytology-the presentation of microscopic findings by live video feed to a cytopathologist at a remote location. However, the initial costs of a telecytology system can be high. We present several low-cost alternatives along with their performance characteristics.

MATERIALS AND METHODS

We tested 3 low-cost telecytology systems: a Raspberry Pi with a webcam, an iPhone 4S with FaceTime, and an iPhone 4S with a live streaming app. Costs, resolution capacities, and latency periods for image transmission were determined.

RESULTS

At $85.55, the Raspberry Pi system is the least expensive telecytology solution described to date. When the cost per megapixel of resolution is considered, the cost of a Raspberry Pi system is 120× less than the most expensive commercially available option and about 7-fold less than the iPhone-based alternatives. Latency periods were substantially lower for the iPhone systems: 2.5 ± 1 seconds for FaceTime and 2.8 ± 0.3 seconds for iPhone live streaming versus 6.6 ± 0.6 seconds for the Raspberry Pi system at comparable frame rates.

CONCLUSIONS

This proof-of-principle study demonstrates that inexpensive telecytology systems are able to stream live video feeds of cytology slides from a microscope to a remote location at useable resolutions.

Cytotechnologists and on-site evaluation of adequacy

While fine needle aspiration (FNA) is certainly not a new biopsy technique, recent developments in advanced imaging techniques, molecular testing, and targeted therapies have coincided with a rapid increase in the number of FNA procedures being performed. Concurrently, the demand for on-site evaluation of adequacy (OSEA) has also increased, outstripping the capacity of available cytopathologists at some institutions. Among the several alternatives to cytopathologist-performed OSEA, cytotechnologist-attended OSEA stands out because it preserves the representation of the pathology service at the time of the procedure. Herein, we review the current literature about OSEA and the necessity of cytotechnologists to expand access of this useful pathology service to a broader patient population. We also examine how cytotechnologists are likely to fit into the emerging practice of telecytology.

Feasibility of telecytopathology for rapid preliminary diagnosis of ultrasound-guided fine needle aspiration of axillary lymph nodes in a remote breast care center

Background:

In the recent years, the advances in digital methods in pathology have resulted in the use of telecytology in the immediate assessment of fine needle aspiration (FNA) specimens. However, there is a need for organ-based and body site-specific studies on the use of telecytology for the immediate assessment of FNA to evaluate its pitfalls and limitations. We present our experience with the use of telecytology for on-site evaluation of ultrasound-guided FNA (USG-FNA) of axillary lymph nodes in a remote breast care center.

Materials and Methods:

Real-time images of Diff-Quik-stained cytology smears were obtained with an Olympus digital camera attached to an Olympus CX41 microscope and transmitted via ethernet by a cytotechnologist to a pathologist who rendered preliminary diagnosis while communicating with the on-site cytotechnologist over the Vocera system. The accuracy of the preliminary diagnosis was compared with the final diagnosis, retrospectively.

Results:

A total of 39 female patients (mean age: 50.5 years) seen at the breast care center underwent USG-FNA of 44 axillary nodes. Preliminary diagnoses of benign, suspicious/malignant, and unsatisfactory were 41, 52, and 7%, respectively. Only one of the 23 cases that were initially interpreted as benign was reclassified as suspicious on final cytologic diagnosis. Seventeen of 18 suspicious/malignant cases on initial cytology corresponded with a malignant diagnosis on final cytology. One suspicious case was reclassified as benign on final cytologic diagnosis. All unsatisfactory cases remained inadequate for final cytologic interpretation. The presence of additional material in the cell block and interpretative error were the main reasons for discrepancy, accounting for the two discrepant cases.

Conclusions:

This retrospective study demonstrates that the on-site telecytology evaluation of USG-FNA of axillary lymph nodes in patients at a remote breast care center was highly accurate compared with the final cytologic evaluation. It allows pathologists to use their time more efficiently and makes on-site evaluation at a remote site possible.

Dynamic telecytopathology for on-site preliminary diagnosis of endoscopic ultrasound-guided fine needle aspiration of pancreatic masses

We evaluated dynamic telecytopathology for on-site-evaluation of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) samples of the pancreas. Realtime images of stained cytology smears were assessed by a cytopathologist while communicating with the on-site operator by telephone. A total of 55 consecutive cases was assessed; preliminary diagnoses of benign, atypical/suspicious and positive for malignancy were 69%, 7% and 24%. We also reviewed 55 consecutive cases of EUS-guided FNA of pancreas which had had conventional microscopic on-site evaluation prior to the introduction of telecytopathology. Preliminary diagnoses of benign, atypical/suspicious and positive for malignancy were 60%, 9% and 31%. The overall concordance between the preliminary and final diagnosis was 84% for telecytopathology and 87% for conventional microscopy. Neuroendocrine neoplasms and well-differentiated adenocarcinoma were diagnostically challenging for both telecytopathology and conventional microscopy. Telecytopathology was similar in accuracy of preliminary diagnosis to conventional microscopy during EUS-FNA of pancreas.