Diagnostic yield and agreement on fine-needle specimens from solid pancreatic lesions : comparing the smear technique to liquid-based cytology

Tissue processing of endoscopic ultrasound-guided fine-needle aspiration specimens from solid pancreatic lesions

Now that tissue cores can be obtained using fine-needle biopsy (FNB) needles, the ways tissues are handled for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) are changing. Direct smear, touch smear of core tissues, and centrifugation have been used for cytological examinations, and liquid-based cytology (LBC), which allows immunostaining and genetic tests that use residual samples, is emerging as an alternative. We emphasize that liquid cytology (Cytospin™ cytology and LBC) is still important, because it enables the diagnosis of pancreatic ductal adenocarcinoma (PDAC) when cancerous cells are scarce in specimens. Cell blocks are being replaced by core tissues obtained via FNB needles. Recent reports indicate that rapid on-site evaluation (ROSE) is not necessary when FNB needles are used, and macroscopic on-site evaluation is used to evaluate specimen adequacy. Macroscopic findings of specimens are helpful in the diagnostic workup and for clarifying specimen-handling methods. In addition to the red strings and white cores observed in PDAC, mixed red and white strings, gray tissues, and gelatinous tissues are observed. Gray (necrotic) tissues and gelatinous (mucus) tissues are more suitable than histology for cell block or cytological processing. Tumor cells in neuroendocrine tumors (NETs) are numerous in red strings but cannot be observed macroscopically. ROSE might thus be necessary for lesions that may be NETs. Core tissues can be used for genetic tests, such as those used for KRAS mutations and comprehensive genomic profiling. Cytological materials, including slides and LBC specimens, can also be genetic test materials.

Evaluation of the diagnostic efficacy of liquid-based cytology obtained via percutaneous ultrasound-guided fine-needle aspiration for pancreatic masses: a large tertiary center's 8-year experience

PURPOSE

There were limited data on the diagnostic efficacy of liquid-based cytology (LBC) for pancreatic tissues acquired by percutaneous ultrasound-guided fine-needle aspiration (US-FNA). This study aimed to evaluate the diagnostic value of LBC acquired via percutaneous US-FNA for pancreatic tumors compared with LBC combined with smear cytology (SC).

METHODS

A retrospective database search (January 2014 and February 2022) was performed for patients who underwent percutaneous US-FNA with both LBC and SC. Clinical and pathological data were collected from 298 patients; eventually, 251 cases met the inclusion criteria. Diagnostic accuracy, sensitivity (SEN), specificity (SPE), positive predictive value (PPV) and negative predictive value (NPV) were compared. Rapid on-site evaluation (ROSE) was not available in all cases.

RESULTS

Based on the pancreaticobiliary cytology guidelines published by the Papanicolaou Society of Cytopathology, 224 (89.2%), 13 (5.2%) and 14 (5.6%) cases were diagnosed as malignant, pre-malignant and benign lesions, respectively. The diagnostic accuracy of the LBC + SC (88.5%) was better than that of LBC (87.3%) but without statistical significance (P = 0.125). The SEN, SPE, PPV and NPV were 87.5%, 85.2%, 98.0% and 45.1%, respectively, in the LBC group and 88.8%, 85.2%, 98.0% and 47.9%, respectively, in the LBC + SC group. According to univariate and multivariate analyses, there were no factors have significant association with the diagnostic sensitivity of LBC.

CONCLUSIONS

LBC obtained via percutaneous US-FNA provides good diagnostic value for pancreatic lesions and there was no significant difference between the diagnostic accuracy of LBC and LBC + SC when ROSE was unavailable.

Conventional versus Liquid-based Cytology: "Man versus Machine"

Background

Liquid-based cytology (LBC) can improve adequacy, monolayer quality with a clean background compared to conventional smears (CS).

Aims and Objectives

The objective was to compare the quality and diagnostic yield of CS and LBC in routine cytological investigations.

Materials and Methods

This retrospective study consisted of 306 samples (255 gynecological, 39 nongynecological, and 12 fine needle aspiration cytology [FNAC]) during a 2-year period (2019-2020). From each patient, two samples were collected in the same manner in the same sitting and processed by CS and LBC (ThinPrep® 2000, Hologic Inc.). Both CS and LBC were compared for adequacy, quality, representativeness, inflammation, hemorrhage, necrosis, preservation, reactive changes, organisms, atypia/dysplasia/malignancy, and preparation/screening time. Statistical analysis was performed.

Results

No statistically significant difference was noted for adequacy, representativeness, reactive changes, preservation, and atypia/dysplasia/malignancy. CS was better in cellularity and diagnosis of inflammation and organisms, whereas LBC had a clean background and the difference was statistically significant (P = 0.0005).

Conclusions

CS was equivalent to LBC in adequacy, representativeness, reactive changes, and atypia/dysplasia/malignancy. Adequacy comparable to LBC can be achieved in CS by careful sample collection, processing, and screening by trained cytotechnologists. CS was better in detecting organisms and inflammation than LBC. The advantages of LBC were monolayer smear, clean background, and lesser screening time, but the demerit was higher cost and longer processing time. Therefore, LBC is best suited to those laboratories having high sample inadequacy rates, lack of competent cytotechnologists, and no financial constraints. Either man or machine, appropriate and adequate sample collection by trained personnel forms the cornerstone for ensuring adequacy in both CS and LBC.

Monitored needle acceleration in endoscopic ultrasound-guided fine-needle aspiration of solid pancreatic masses improves sample quality and diagnostic accuracy: a randomized trial

BACKGROUND : Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is recommended for the diagnosis of solid pancreatic masses. We aimed to evaluate whether a high needle movement acceleration value during puncture increases diagnostic accuracy. METHODS : EUS-FNA needle acceleration was measured using a PocketLab accelerometer connected by Bluetooth to a smartphone. Two passes (fast and slow, with higher and lower than 1g [9.8 m/s²] needle acceleration values, respectively) were performed in a random order. The sample cellularity and quality were measured using semiquantitative scales. RESULTS : 51 patients were included (32 women; mean age 63). The mean (standard deviation [SD]) acceleration values were 1.59g (0.66g) for the fast pass and 0.32g (0.19g) for the slow pass (P < 0.001). The fast pass yielded significantly higher levels of EUS-FNA accuracy (84.3 % vs. 68.6 %; P = 0.02) and adequate quality scores (94.1 % vs. 76.5 %; P = 0.007). High cellularity scores were seen with similar frequencies (15.7 % vs. 11.8 %; P = 0.32). CONCLUSIONS : A higher than 1g EUS-FNA needle acceleration may increase the diagnostic accuracy and specimen quality from solid pancreatic lesions.

Endoscopic tissue sampling - Part 1: Upper gastrointestinal and hepatopancreatobiliary tracts. European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that, where there is a suspicion of eosinophilic esophagitis, at least six biopsies should be taken, two to four biopsies from the distal esophagus and two to four biopsies from the proximal esophagus, targeting areas with endoscopic mucosal abnormalities. Distal and proximal biopsies should be placed in separate containers.Strong recommendation, low quality of evidence. 2: ESGE recommends obtaining six biopsies, including from the base and edge of the esophageal ulcers, for histologic analysis in patients with suspected viral esophagitis.Strong recommendation, low quality of evidence. 3: ESGE recommends at least six biopsies are taken in cases of suspected advanced esophageal cancer and suspected advanced gastric cancer.Strong recommendation, moderate quality of evidence. 4: ESGE recommends taking only one to two targeted biopsies for lesions in the esophagus or stomach that are potentially amenable to endoscopic resection (Paris classification 0-I, 0-II) in order to confirm the diagnosis and not compromise subsequent endoscopic resection.Strong recommendation, low quality of evidence. 5: ESGE recommends obtaining two biopsies from the antrum and two from the corpus in patients with suspected Helicobacter pylori infection and for gastritis staging.Strong recommendation, low quality of evidence. 6: ESGE recommends biopsies from or, if endoscopically resectable, resection of gastric adenomas.Strong recommendation, moderate quality of evidence. 7: ESGE recommends fine-needle aspiration (FNA) and fine-needle biopsy (FNB) needles equally for sampling of solid pancreatic masses.Strong recommendation, high quality evidence. 8: ESGE suggests performing peroral cholangioscopy (POC) and/or endoscopic ultrasound (EUS)-guided tissue acquisition in indeterminate biliary strictures. For proximal and intrinsic strictures, POC is preferred. For distal and extrinsic strictures, EUS-guided sampling is preferred, with POC where this is not diagnostic.Weak recommendation, low quality evidence. 9: ESGE suggests obtaining possible non-neoplastic biopsies before sampling suspected malignant lesions to prevent intraluminal spread of malignant disease.Weak recommendation, low quality of evidence. 10: ESGE suggests dividing EUS-FNA material into smears (two per pass) and liquid-based cytology (LBC), or the whole of the EUS-FNA material can be processed as LBC, depending on local experience.Weak recommendation, low quality evidence.

Comparison of smear cytology with liquid-based cytology in pancreatic lesions: A systematic review and meta-analysis

BACKGROUND

Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) is a safe and accurate technique to confirm the diagnosis of pancreatic cancers. Recently, numerous studies comparing the diagnostic efficacy of smear cytology (SC) and liquid-based cytology (LBC) for pancreatic lesions yielded mixed results.

AIM

To compare and identify the better cytology method for EUS-FNA in pancreatic lesions.

METHODS

A comprehensive search of PubMed, Embase, and Cochrane was undertaken through July 18, 2020. The primary endpoint was diagnostic accuracy (sensitivity and specificity). Secondary outcomes included sample adequacy and post procedure complications. In addition, factors affecting diagnostic efficacy were discussed.

RESULTS

Data on a total of 1121 comparisons from 10 studies met the inclusion criteria. Pooled rates of sensitivity for SC and LBC were 78% (67%-87%) vs 75% (67%-81%), respectively. In any case, both SC and LBC exhibited a high specificity close to 100%. Inadequate samples more often appeared in LBC compared with SC. However, the LBC samples exhibited a better visual field than SC. Very few post procedure complications were observed.

CONCLUSION

Our data suggested that for EUS-FNA in pancreatic lesions (particularly solid lesions), SC with Rapid On-Site Evaluation represents a superior diagnostic technique. If Rapid On-Site Evaluation is unavailable, LBC may replace smears. The diagnostic accuracy of LBC depends on different LBC techniques.

Comparison of EUS-guided conventional smear and liquid-based cytology in pancreatic lesions: A systematic review and meta-analysis

Background and study aims  Endoscopic ultrasound (EUS)-guided fine-needle aspiration (EUS-FNA) has limitations of inadequate sampling and false-negative results for malignancy. It has been performed using conventional smear (CS) cytology with rapid on-site evaluation (ROSE) with reasonable diagnostic accuracy. An alternative to ROSE is liquid-based cytology (LBC). Commonly used LBC techniques include precipitation-based (SurePath™) and filtration-based (ThinPrep ^® , CellPrep ^® ). Data regarding the diagnostic efficacy of LBC compared with CS are limited. Methods  Multiple databases were searched through March 2020 to identify studies reporting diagnostic yield of EUS-guided CS and LBC in pancreatic lesions. Pooled diagnostic odds and rates of performance for the cytologic diagnoses of benign, suspicious, and malignant lesions were calculated. Diagnostic efficacy was evaluated by pooled rates of accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results  Nine studies with a total of 1308 patients were included in our final analysis. Pooled diagnostic odds of CS cytology were 1.69 (CI 1.02-2.79) and 0.39 (CI 0.19-0.8) for malignant lesions when compared to filtration-based and precipitation-based LBC techniques, respectively. For CS, precipitation-based and filtration-based LBC, pooled diagnostic accuracy was 79.7 %, 85.2 %, 77.3 %, sensitivity was 79.2 %, 83.6 %, 68.3 %, and specificity was 99.4 %, 99.5 %, 99.5 %, respectively. Conclusions  The precipitation-based LBC technique (SurePath™) had superior diagnostic odds for malignant pancreatic lesions compared with CS cytology in the absence of ROSE. It showed superior accuracy and sensitivity, but comparable specificity and PPV. Diagnostic odds of CS cytology in the absence of ROSE were superior to the filtration-based LBC technique (ThinPrep ^® , Cellprep ^® ) for diagnosing malignant pancreatic lesions.

Diagnostic value of liquid-based cytology and smear cytology in pancreatic endoscopic ultrasound-guided fine needle aspiration: A meta-analysis

BACKGROUND

Smear cytology (SC) using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the established and traditional choice for diagnosing pancreatic lesions. Liquid-based cytology (LBC) is a novel alternative cytological method, however, the comparative diagnostic efficacy of LBC remains inconclusive.

AIM

To examine the diagnostic efficacy of LBC and SC for pancreatic specimens obtained through EUS-FNA via a systematic review and meta-analysis.

METHODS

A systematic literature search was performed using PubMed, EMBASE, the Cochrane Library, and Web of Science. The numbers of true positives, false positives, true negatives, and false negatives for each cytological test (LBC and CS) were extracted from the included studies. The pooled sensitivity and specificity and the area under the summary receiver operating characteristic curve (AUC) were calculated, and the AUC was compared by Tukey's multiple comparisons test. The quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies II tool.

RESULTS

A total of 1656 patients in eight studies were included. The pooled sensitivity and specificity and the AUC for LBC were 0.76 (95%CI: 0.72-0.79), 1.00 (95%CI: 0.98-1.00), and 0.9174, respectively, for diagnosing pancreatic lesions. The pooled estimates for SC were as follows: Sensitivity, 0.68 (95%CI: 0.64-0.71); specificity, 0.99 (95%CI: 0.96-100.00); and AUC, 0.9714. Similarly, the corresponding values for LBC combined with SC were 0.87 (95%CI: 0.84-0.90), 0.99 (95%CI: 0.96-1.00), and 0.9894. Tukey’s multiple comparisons test was used to compare the sensitivities and AUCs of the three diagnostic methods; statistically significant differences were found between the three methods, and LBC combined with SC was superior to both LBC (P < 0.05) and SC (P < 0.05). The pooled sensitivity and AUC did not change significantly in the sensitivity analysis.

CONCLUSION

LBC may be sensitive than SC in the cytological diagnosis of pancreatic lesions, however, the superior diagnostic performance of their combination emphasizes their integrated usage in the clinical evaluation of pancreatic lesions.