Impact of touch imprint cytology on imaging-guided core needle biopsies: An experience from a large academic medical center laboratory

Fusion of old and new: Employing touch imprint slides for next generation sequencing in solid tumors

BACKGROUND

Cytomorphological evaluation of tissue touch imprints during rapid on-site evaluation or intraoperative pathology consultation has crucial value. However, literature on their utility for molecular testing is limited. In this study, we emphasize a further benefit of touch imprint slides and scrutinize our institutional experience on their use in molecular testing, specifically next generation sequencing (NGS).

MATERIALS AND METHODS

NGS-based reports (2019-2023) of Koç University Hospital were retrospectively analyzed and circumstances in which sequencing was conducted on touch imprint slides were retrieved (n = 18). Type/location of the biopsy, diagnosis, results, and quality metrics were recorded.

RESULTS

Touch imprints were addressed when they harbored more neoplastic cells compared with permanent biopsies, when suboptimal fixation mitigated deoxyribonucleic acid/ribonucleic acid (DNA/RNA) yield in resections or when the sample was obtained from bone and required decalcification. Diagnoses were diverse, namely non-small-cell lung cancer, gastric adenocarcinoma, glial tumor, Ewing sarcoma, and carcinoma of unknown primary. The percentage of tumor cells on slides stretched between 15% and 70%. Molecular findings ranged from KRAS mutations to TRIM1::NTRK2 and EWSR::FLI1 fusions. For five cases, sequencing did not yield any alteration, one study was not completed because it did not yield high-quality RNA.

CONCLUSION

Touch imprint slides provide a reliable alternative, especially when neoplastic cells are scarce in permanent biopsies or decalcification deters nucleic acid quality. Based on our experience, we suggest making touch imprints on a routine basis, especially for every bone biopsy. Once digitally scanned duplicates are made, original slides can be safely used for DNA-/RNA-based molecular studies.

Ultrasound-guided core biopsy with on-site cytology-immediate diagnosis in pediatric oncology

BACKGROUND

Accurate and swift tissue diagnosis is extremely important for the timely initiation of treatment in pediatric oncology. In our department, ultrasound-guided core needle biopsy (US-guided CNB) is used for tissue diagnosis. In 2016, we added on-site cytology, allowing for an immediate primary diagnosis. We retrospectively reviewed our performance in terms of safety and accuracy for CNBs and on-site cytology.

METHODS

All pediatric biopsies performed in our hospital between February 2016 and December 2020, were included. Patient clinical, procedural and follow-up data were collected. CNB pathology and cytology results were compared to the final pathologic diagnosis.

RESULTS

We included 71 patients for which 72 biopsies with on-site touch imprint (TI) cytology were performed; the average latency time to biopsy was 1 day. Altogether, we had 61 tumors, (58 malignant, 3 benign) and 11 other lesions. On-site cytology diagnosed 58 malignant tumors, 3 benign tumors and 11 non-tumor tissues. The cytologist correctly differentiated tumor from inflammation in all cases, and diagnosed the precise tumor type in 57 cases, with an accuracy of 94% for final diagnosis. We had no complications related to the procedure or sedation.

CONCLUSION

US-guided CNB with on-site TI cytology for suspected malignancy in the pediatric population is highly available, safe, and accurate, with real-time diagnosis in most cases. This accelerated diagnostic route has a huge impact on patient care.

Ultrasound-Guided Core Biopsy for Tissue Diagnosis in Pediatric Oncology: 16-Year Experience With 597 Biopsies

OBJECTIVE. Percutaneous imaging-guided core needle biopsies (CNBs) for cancer diagnosis in pediatric patients are gaining interest because of their availability, lower rate of complications, and high diagnostic power compared with traditional surgical biopsies. Nevertheless, their precise role in the diagnostic algorithm of pediatric oncology is still unknown. The purpose of this study was to report our accumulated 16-year experience with CNB; discuss the availability, safety, and diagnostic accuracy of the procedure and the adequacy of ancillary testing; and compare our findings with the available literature. MATERIALS AND METHODS. Pediatric ultrasound-guided CNBs performed in our hospital between November 2003 and December 2019 were retrospectively studied. Data collection included demographics, clinical and procedural parameters, complications, and final diagnosis. RESULTS. A total of 597 biopsies were performed in 531 patients (132 performed in known oncologic patients and 465 performed to establish diagnosis). The median time between the biopsy request and the procedure was 1 day. Of 432 biopsies performed in patients with malignancies, 12 (2.8%) had false-negative results. In 165 cases of benign pathologic findings, all had true-negative results. Ancillary testing was adequate in all malignant cases. Overall sensitivity, specificity, and accuracy rates were 97.2%, 100%, and 98.0%, respectively. Five biopsies (0.8%) resulted in complications, including one major bleed and one track seeding. CONCLUSION. Our experience shows that ultrasound-guided CNB for suspected malignancy in pediatric patients has a high safety profile, availability, and accuracy rate compared with surgical biopsy. Our fast-track strategy enables early initiation of designated therapy and has the potential to become the procedure of choice.

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.

Imprint Cytology of Thoracoscopic Pleural Biopsy Tissue for Early Etiological Diagnosis of Pleural Effusion: A Pilot Study From India

Thoracoscopic pleural biopsy provides the highest diagnostic yield in both malignant and tubercular pleural effusions. However histopathologic report takes 3 to 5 days to provide the diagnosis, resulting in a delay of further management plans like pleurodesis or chest tube removal. Imprint cytology of biopsy tissue can provide early information about the etiological diagnosis. Thus, we conducted this pilot study in 66 patients of exudative pleural effusions undergoing medical thoracoscopy. One or 2 biopsy pieces obtained during medical thoracoscopy from pleural nodules were used to prepare imprint cytology slides in the thoracoscopy suite. In comparison to thoracoscopic pleural biopsy, the diagnostic yield of imprint cytology of pleural tissue was 92% (49 of 53 cases) in cases of malignant pleural effusion and 75% (9 of 12 cases) in cases of tuberculosis pleural effusions. Imprint cytology provided a definite idea about the type of diagnosis, about 2.5 days before the histopathology results. By providing early etiological diagnosis, it may also decrease the duration of hospital stay and health care expenditure. A large prospective trial has been planned in our center to confirm this hypothesis.

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.

An update on touch preparations of small biopsies

Touch preparations (TPs) are being increasingly utilized in the era of personalized medicine. They fill a gap in cytopathology practice by providing a method to perform rapid onsite evaluation of small tissue samples such as core needle biopsies. However, there is a paucity of literature about how best to perform and interpret a TP. A high-quality TP can provide excellent diagnostic accuracy and good concordance with core needle biopsy histopathology findings. Although many of the cytomorphologic features of TPs overlap with fine needle aspirate smears, TP cytology is unique and differs from conventional smears in many aspects. It is important for cytologists to recognize these features, as well as potential pitfalls and artifacts in order to avoid misinterpretation. Core depletion of tumor cells is a notable drawback if TPs are performed too aggressively. TP slides are also valuable for ancillary testing because they often contain a cellular and pure population of whole tumor cells. This paper reviews all of the aspects of TPs including their clinical utility, proper slide preparation techniques, distinctive cytomorphologic characteristics, limitations, and potential pitfalls.

Comparison of Real-Time Fluorescence Confocal Digital Microscopy With Hematoxylin-Eosin-Stained Sections of Core-Needle Biopsy Specimens

IMPORTANCE

Strategies to procure high-quality core-needle biopsy (CNB) specimens are critical for making basic tissue diagnoses and for ancillary testing.

OBJECTIVES

To investigate acquisition of fluorescence confocal microscopy (FCM) images of interventional radiology (IR)-guided CNB in real time in the radiology suite and to compare the accuracy of FCM diagnoses with those of hematoxylin-eosin (H&E)-stained CNB sections.

DESIGN, SETTING, AND PARTICIPANTS

In this diagnostic study, FCM imaging of IR-guided CNBs was performed in the radiology suite at a major cancer center for patients with an imaging abnormality from August 1, 2016, to April 30, 2019. The time taken to acquire FCM images and the quality of FCM images based on percentage of interpretable tissue with optimal resolution was recorded. The FCM images were read by 2 pathologists and categorized as nondiagnostic, benign/atypical, or suspicious/malignant; these diagnoses were compared with those made using H&E-stained tissue sections. Cases with discrepant diagnosis were reassessed by the pathologists together for a consensus diagnosis. Data were analyzed from June 3 to July 19, 2019.

INTERVENTIONS

Each IR-guided CNB was stained with 0.6mM acridine orange, subjected to FCM imaging, and then processed to generate H&E-stained sections.

MAIN OUTCOMES AND MEASURES

Mean time taken for acquisition of FCM images, quality of FCM images based on interpretable percentage of the image, and accuracy of diagnostic categorization based on FCM images compared with H&E-stained sections.

RESULTS

A total of 105 patients (57 male [54.3%]; mean [SD] age, 63 [13] years) underwent IR-guided CNBs in a mean (SD) of 7 (2) minutes each. The FCM images showed at least 20% of the tissue with optimal quality in 101 CNB specimens (96.2%). The FCM images were accurately interpreted by the 2 pathologists in 100 of 105 cases (95.2%) (2 false-positive and 3 false-negative) and 90 of 105 cases (85.7%) (6 false-positive and 9 false-negative). A reassessment of 14 discordant diagnoses resulted in consensus diagnoses that were accurate in 101 of 105 cases (96.2%) (1 false-positive and 3 false-negative).

CONCLUSIONS AND RELEVANCE

The ease of acquisition of FCM images of acceptable quality and the high accuracy of the diagnoses suggest that FCM may be useful for rapid evaluation of IR-guided CNBs. This approach warrants further investigation.

Role of cytotechnologists in rapid onsite adequacy assessment of cytology materials for diagnostic workup and specimen allocation for ancillary testing using a standardized protocol

INTRODUCTION

Data on the performance of cytotechnologists in assessing specimen adequacy of needle core biopsies (NCB) is scant and their role in specimen triaging for ancillary studies have not been well established.

MATERIALS AND METHODS

We retrospectively analyzed rapid onsite evaluation (ROSE) performed exclusively by cytotechnologists on 248 NCB and fine-needle aspiration (FNA) specimens. Overall adequacy and accuracy rates were determined by comparing to final diagnosis. We also reviewed the process of specimen allocation for ancillary testing to determine whether specimens were appropriately triaged at the time of ROSE.

RESULTS

Of the 248 cases, 222 (89.5%) were touch imprint and 26 (10.5%) were FNA smears. The overall adequacy rate was 73.4% (182 of 248). Concordance for "adequate" interpretation by ROSE with unequivocal malignant or benign diagnoses on final interpretation was 95.6%. The sensitivity, specificity, and accuracy of ROSE for a final "positive for malignancy" were 89.2% (95% CI 83.04% to 93.69%), 43.24% (95% CI 31.77% to 55.28%), and 73.87% (95% CI 67.57% to 55.28%), respectively. Cases with "positive for malignancy" on final diagnosis were "adequate" by ROSE in 89.1% (132 of 148) and "inadequate" in 10.8% (16 of 148), P < 0.0001. Ancillary tests were performed in 168 of 248 (67.7%); the majority were immunohistochemical stains for determining tumor subtype. Predictive biomarkers were performed successfully in 100% of metastatic breast cancers.

CONCLUSIONS

Cytotechnologists performed at a high level of competency in providing ROSE and allocating specimens for ancillary testing, which were performed successfully in the majority of cases. Implementation of a standardized protocol for tissue management/prioritization is of paramount importance to maximize tissue preservation and minimize wastage.

Diagnostic value of imprint cytology testing in kidney tumors: review of 200 cases

INTRODUCTION

Previous investigations have studied the importance of imprint cytology (IC) testing of core needle biopsy (CNB) from various organs. We have presented the largest series, to the best of our knowledge, of IC testing of CNB for patients with kidney tumors.

MATERIALS AND METHODS

The present retrospective study (January 1, 2015, through January 30, 2016) identified laboratory information through a computer search of the cytology archived reports for 200 consecutive IC testing with CNB for renal tumors cases. A board-certified cytopathologist and cytology-trained fellow reviewed the IC testing and CNB slides and rendered them as nondiagnostic, positive for malignancy, negative for malignancy, positive for neoplasm, or atypical. The tumors were graded using the International Society of Urological Pathology grading system. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

RESULTS

The IC testing cases classified as atypical (n = 53) or positive for neoplasm (n = 28) were evaluated separately because of the ambiguous morphologic characteristics. Of the other 119 cases, IC testing classified 95 (80%) as positive for malignancy, 5 (4%) as negative for malignancy, and 19 (16%) as nondiagnostic. The corresponding CNB histologic diagnoses showed that 85 of 95 cases (89%) were true positive for malignancy. Of these 85 cases, 45 (53%) were low grade, 21 (25%) were high grade, and 19 (22%) were ungraded. The corresponding sensitivity, specificity, and accuracy were 85%, 11%, and 58%, respectively. The 53 IC-identified atypical cases were more likely to be malignant (n = 40; 75%). Of the remaining IC testing atypical cases, 12 (23%) were negative for malignancy and 1 (2%) was nondiagnostic. Of the 28 cases positive for neoplasm using IC, 13 (46%) were positive and 15 (54%) were negative for malignancy.

CONCLUSIONS

The relatively low diagnostic value of IC testing for renal tumors showed it to be less powerful for screening than its use in other organs.

Adequacy and Accuracy of Core Biopsy in Children: A Radiologic/Pathologic Correlation Study

Core biopsy (CB) is increasingly popular for assessing solid lesions in children. To date, pediatric literature is limited regarding factors contributing to diagnostically inadequate or inaccurate CB. Therefore, we retrospectively examined radiologic/pathologic factors associated with adequacy/accuracy of CB in pediatric patients. A search of the surgical pathology database for CB between January 2007 and December 2014 yielded 134 CB from 99 patients. Age, sex, anatomic site of lesion, CB diagnosis, and final diagnosis were acquired from the electronic medical record. Image guidance modality, lesion size, and CB sampling device were obtained from radiology records. CB hematoxylin and eosin slides were reviewed for fragmentation, percentage of fibrosis, and percentage of necrosis. Overall, CB length was measured using cellSens software and a DP71 camera. Groups were compared using 2-sided homoscedastic Student's t tests; 87.3% (117/134) CB were diagnostic; final diagnosis was available for 105 cases, with a concordance rate of 80.0% (84/105). Image guidance modality, lesion site (extremity vs nonextremity), and CB needle gauge did not significantly differ between diagnostic versus nondiagnostic CB or concordant versus discordant CB. Diagnostic CB had less necrosis and fibrosis than did nondiagnostic CBs (6.8% vs 29.7%, P = .0002 and 10.3% vs 29.1%, P = .0006). Nondiagnostic and discordant CB were more likely to be from bony lesions than soft tissue ( P = .01 and P = .0248). CB is valuable for diagnosing solid lesions in children, with good overall diagnostic rates regardless of lesion size, location, or imaging modality used for biopsy. Nondiagnostic and discordant CB were more often obtained from bony lesions; sampling via open biopsy may be more useful in that setting. Nondiagnostic and discordant CB have more necrosis and fibrosis, suggesting that on-site evaluation of CB tissue viability-for example, by touch imprint or fine needle aspiration-may be useful in further enhancing CB utility.

Confocal Fluorescence Microscopy Platform Suitable for Rapid Evaluation of Small Fragments of Tissue in Surgical Pathology Practice

CONTEXT.—

Rapid advances in the fields of biophotonics, computer science, and instrumentation have allowed for high-resolution imaging of biologic tissues.

OBJECTIVE.—

To evaluate the quality of images from an optimized confocal fluorescence microscopy (CFM) platform for rapid evaluation of small fragments of tissue, compared with hematoxylin-eosin staining.

DESIGN.—

Tissue fragments (up to 1.0 × 0.3 cm) were stained with 0.6 mM acridine orange for 60 seconds and imaged using a CFM platform at 488-nm and 785-nm wavelength. The imaged tissues were then fixed in formalin and processed to generate hematoxylin-eosin-stained tissue sections. The quality of CFM images was scored on a scale of 0 to 3 on the basis of the percentage of the CFM images with recognizable tissue architecture (0, 0%; 1, <20%; 2, 20%-50%; 3, >50%). The diagnoses made using CFM images were compared with those made using histopathologic analysis of the hematoxylin-eosin-stained tissue sections.

RESULTS.—

We imaged 118 tissue fragments obtained from 40 breast, 23 lung, 39 kidney, and 16 liver surgical excision specimens. We acquired CFM images in 2 to 3 minutes; 95.8% (113 of 118) of images showed a quality score of 3, and 4.2% (5 of 118) had a score of 2. We achieved a sensitivity of 95.5%, specificity of 97.3%, positive predictive value of 95.5%, and negative predictive value of 97.3%.

CONCLUSIONS.—

Our results demonstrate the suitability of the CFM platform for rapid and accurate evaluation of small tissue fragments in surgical pathology practice.