Aims To develop, deploy and evaluate artificial intelligence (AI) for triaging duodenal biopsies within a National Health Service (NHS) histopathology laboratory, with the aim of improving reporting turnaround times for clinically significant diagnoses. Methods The pathway was developed in the UK in an NHS laboratory. Rule-based automation software was used to find all newly scanned duodenal biopsy slides. Those with case numbers ending in an odd number were exported for AI triage and if they had significant AI predicted abnormalities they were prioritised for reporting. The cases with even numbers followed the routine reporting pathway. Results 313 cases (517 duodenal slides) were processed by the routine pathway, and 329 cases (533 duodenal slides) were processed by the AI triage pathway. AI processing took about 70 s per slide. The AI classifier had a sensitivity and positive predictive value (PPV) as follows: normal small bowel: 99.6%, 95.7%; coeliac disease: 86.7%, 100%; gastric heterotopia: 84.6%, 95.7%; adenoma: 88.9%, 88.9%; adenocarcinoma: 50.0%, 100%. In the AI triage workstream coeliac disease, and non-neoplastic abnormalities as a group, were reported quicker than in the standard workstream (6 days vs 10 days and 7 days vs 10 days, respectively, both p<0.005), but neoplastic lesions were not reported quicker. The cost of deployment and operation was reasonable. Conclusions An NHS histopathology laboratory successfully developed and implemented an AI-based triage system for duodenal biopsies, achieving high diagnostic accuracy and significantly improving turnaround times for coeliac disease and non-neoplastic abnormalities as a group. This study demonstrates the feasibility and clinical value of locally developed AI tools within routine diagnostic practice.

Background:Large bowel biopsies are one of the commonest types of biopsy specimen. We describe a service evaluation study to test the feasibility of using artificial intelligence (AI) to triage large bowel biopsies from a reporting backlog and prioritize those that require more urgent reporting.Methods:The pathway was developed in the UK by National Health Service (NHS) laboratory staff working in a medium-sized general hospital.   The AI platform was interfaced with the slide scanner software and the reporting platform's software, so that pathologists could correct the AI label and reinforce the training set as they reported the cases.Results:he AI classifier achieved a sensitivity of 97.56% and specificity of 93.02% for the case-level-diagnosis of neoplasia (adenoma and adenocarcinoma) and for an AI diagnosis of any significant pathology (i.e., adenomas, adenocarcinomas, inflammation, hyperplastic polyps, and sessile serrated lesions) sensitivity was 95.65% and specificity 92.96%. The automated AI diagnostic classification pathway took approximately 175 s per slide to download and process the scanned whole slide image (WSI) and return an AI diagnostic classification. Biopsies with an AI diagnosis of neoplasia or inflammation were prioritized for reporting while the remainder followed the routine reporting pathway. The AI triaged pathway resulted in a significantly shorter reporting turnaround time for pathologist verified neoplastic cases (P < 0.001) and inflammation (P < 0.05). The project's costs amounted to  £14800, excluding laboratory staff salaries. More time and resources were spent on developing the interface between the AI platform and laboratory IT systems than on the development of the AI platform itself.Conclusions:NHS laboratory staff were able to implement an AI solution to accurately triage large bowel biopsies into several diagnostic classes and this improved reporting turnaround times for cases with neoplasia or with inflammation.

An artificial intelligence (AI) platform was trained by a consultant histopathologist to classify whole slide images (WSIs) of large bowel biopsies. Six medical students viewed WSIs of five large bowel biopsy cases and assigned the WSIs to one of the nine diagnostic categories. Then the students compared their answers with those generated by the AI. This training was repeated for a total of six rounds of five cases, and the accuracy of the students was recorded for each round. Each case had one or more WSIs. The student with the best final accuracy was asked to describe the morphological features that they had deduced. All the students improved during their training, from a mean accuracy of 13.7% in the first round to a mean accuracy of 77.1% in the sixth round (p = 0.0011). The student-deduced diagnostic features were mainly accurate. Some students learned more quickly than others.

Background: The objective of the project was to evaluate the feasibility of introducing a single-networked digital histopathology reporting platform in the Southwest Peninsula region of England by allowing pathologists to experience the technology and recording their perceptions. This information was then used in planning future service development. The project was funded by the National Health Service (NHS) Peninsula Cancer Alliance and took place in 2020 during the COVID-19 pandemic. Materials and Methods: Digital slides of 500 cases from Taunton were reported remotely in Truro, Plymouth, Exeter, Bristol, or Bath by using a single remote reporting platform located on the secure Health and Social Care Network (HSCN) that links NHS sites. These were mainly small gastrointestinal, skin, and gynecological specimens. The digital diagnoses were compared with the diagnoses issued on reporting the glass slides. At the end of the project, the pathologists completed a Google Forms questionnaire of their perceptions of digital pathology. The results were presented at a meeting with the funder and discussed. Results: From the 500 cases there were nine cases of significant diagnostic discrepancy, seven of which involved the misrecognition of Helicobacter pylori in gastric biopsies. The questionnaire at the end of the project showed that there was a general agreement that the platform was easy to use, and the image quality was acceptable. It was agreed that extra work, such as deeper levels, was easy to request on the software platform. Most pathologists did not agree that digital reporting was quicker than glass slide reporting. Some were less confident in their digital diagnoses than glass diagnoses. They agreed that some types of specimens cannot easily be reported digitally. All users indicated that they would like to report at least half of their work digitally in the future if they could, and all strongly agreed that digital pathology would improve access to expert opinions, teaching, and multidisciplinary meetings. It was difficult to find pathologists with time to undertake remote digital reporting, in addition to their existing commitments. Conclusions: Overall, the pathologists developed a positive perception of digital pathology and wished to continue using it.

OBJECTIVE:The study set out to assess the feasibility of using ParsortixTM circulating tumour cell (CTC) extraction and CytoFoam Disc cell-block immunohistochemistry to diagnose metastatic carcinoma from blood samples in a National Health Service district general hospital.METHODS:Blood samples were taken from 50 patients with metastatic carcinoma and 50 healthy volunteers and processed, using a previously published method, to extract CTCs and collect them in a cell-block for routine formalin-fixed paraffin sectioning and immunohistochemistry. The extracted cells were compared with the patients' routine diagnostic samples.RESULTS:The samples from the 50 carcinoma patients showed cytokeratin-positive cells in 19 cases. In eight of these, the cytokeratin-positive cells had a similar immunoprofile to the carcinoma in the conventional biopsy or cytology specimen. Some carcinoma patients also had circulating cytokeratin-positive cells that were probably benign epithelial cells and circulating megakaryocytes. Both of these types of cells were also found in healthy volunteers. Processing and initial examination could be completed in 2 days. The full processing cost was approximately £316 per case.CONCLUSIONS:CTCs could be extracted from the blood of some patients with metastatic carcinoma and formed into a formalin-fixed cell-block for routine paraffin processing and immunohistochemistry. The specificity of this approach is constrained by the observation that some patients with metastatic carcinoma had circulating cytokeratin-positive cells that were probably benign, and these were also found in healthy volunteers. Circulating megakaryocytes were present in carcinoma patients and healthy volunteers.

We describe a method for preparing a cell block from a very sparsely cellular cytology fluid sample. The aim is to ensure that cells are not lost during processing. We developed this method to perform immunohistochemistry on circulating tumour cells (CTC) extracted from the blood of patients with metastatic carcinoma, in which there are typically less than 20 cells in a 10 mL blood sample. The method could also be applicable to other sparsely cellular samples such as cerebrospinal fluid (CSF) samples, or eye vitreous fluid samples. First, the cells are concentrated into a 90 µL volume of fluid. In the case of CTCs this is obtained from a phosphate buffered saline backwash of a Parsortix CTC blood filter cassette (figure 1A–C; arrows mark CTCs). This filter cassette separates cells based on their size and deformability. Circulating carcinoma cells, and cells from other non-haematological neoplasms, tend to be larger and more rigid than other blood cells. The concentrate could also be from centrifugation of a CSF sample, vitreous humour or similar, with removal of most of the supernatant and …

Intravascular leiomyomatosis (IVL) is characterized by the presence of smooth muscle in venous and lymphatic spaces within the myometrium. Although the intravascular component usually consists solely of typical smooth muscle or variants of smooth muscle differentiation, we report 5 cases in which the intravascular component also included endometrioid glandular and stromal elements. We propose the term "intravenous adenomyomatosis" to describe this unusual variant of IVL. The mean age of the patients in this series was 50.2 years, slightly older than that of patients with conventional IVL. In addition to intravenous adenomyomatosis, both adenomyosis and leiomyomas were identified in all of our cases, supporting the hypothesis that the intravascular smooth muscle component in IVL is derived from associated myometrial pathology rather than from vessel walls. In our series, intravenous adenomyomatosis had a similar benign clinical behavior to most cases of IVL with no metastatic or recurrent disease identified at follow-up in 4 cases for which follow-up information was available. The main differential diagnoses are adenomyosis with vascular involvement, low-grade endometrial stromal sarcoma (ESS), including ESS with smooth muscle and glandular differentiation, and adenosarcoma with lymphovascular invasion. The possibility of intravenous adenomyomatosis should be borne in mind when considering these diagnoses, particularly ESS and adenosarcoma, which have different implications for patient management and prognosis.

Cell block immunohistochemistry (IHC) and other molecular studies are often required to fully characterise tumours diagnosed by fine needle aspiration (FNA) cytology. These supplementary investigations are best done on cell blocks. We describe a device that allows cell blocks to be collected while performing FNAs with little extra effort or reduction in the quality of the cytology smear specimen. Experienced FNA operators will recognise that often a significant amount of the sample is left behind in the hub of the needle when the specimen is ejected on the slides (figure 1A). Figure 1 (A): Residual fine needle aspiration cytology material is often left in the hub of the needle after the specimen has been ejected. (B): The foam residue device consists of a core of polyvinyl alcohol foam housed in a Luer type plastic adapter. (C): The device attaches to a needle and syringe. (D): The sample is absorbed into the tip of the foam core. (E): After formalin fixation the core is removed from the adapter, paraffin processed and sectioned (F) in the usual way. (G): Adenocarcinoma cells within the polyvinyl alcohol foam. (H): Adenocarcinoma cells immunostained for cytokeratin 7. (J): The tip of the foam core can also be used to collect material from the surface of a slide. We …

The authors describe a simple method for making formalin or isopropyl alcohol vapour fixed cell blocks from fine needle aspiration cytology specimens that we refer to as 'The Poor Man's Cell Block.'

This report describes a simple method of preparing cell blocks from fluids submitted for cytology, using croutons of gelatin foam surgical dressing material.

F. Mayall, A. Cormack, S. Slater and K. McAnulty The utility of assessing the gross appearances of FNA specimens Objective: Ideally, fine needle aspiration (FNA) cytology should be performed with near‐patient assessment of the adequacy of the specimen by a cytopathologist. However, this is often not feasible. A cruder alternative is for the FNA practitioner to examine the gross appearances of the specimen and to try to predict the its quality. This study set out to determine the value of this approach.Methods: The study was conducted in tertiary public hospitals in New Zealand and the UK. FNA gross material grading was performed by a variety of pathologists on FNA samples taken using manual guidance and image guidance. The FNA gross material grade was compared with the findings on microscopic examination.Results: Nine out of 123 FNA samples were assessed as Grade 1 (unlikely to contain diagnostic material). All were subsequently reported as having insufficient diagnostic tissue on microscopic examination. Forty‐two of the FNA samples were assessed as Grade 2 (possibly contains diagnostic material) and 46 as Grade 3 (probably contains diagnostic material). None from either of these grades was reported as showing insufficient diagnostic material on microscopic examination. Twenty‐six cases were reported as Grade 4 (material suggesting a specific diagnosis). None of these was reported as showing insufficient diagnostic material on microscopic examination. The most common Grade 4 provisional diagnosis was that of a colloid cyst or colloid nodule of the thyroid (seven cases). Only two cases had misleading Grade 4 provisional diagnoses. Both were thought to be pus on gross examination but showed necrotic carcinoma on microscopic examination.Conclusions: The gross appearances of FNA samples can usually predict the adequacy of the samples and sometimes predict the final microscopic diagnosis. However, near‐patient microscopic assessment of FNA specimens is preferable if available.

Aims: This study set out to photograph and describe the gross appearances of fine needle aspiration (FNA) cytology samples of commonly encountered lesions.Methods: During a 2 year period, a cytopathologist photographed the gross appearances of near patient FNA samples, concentrating on commonly encountered lesions.Results: The gross appearances are described, accompanied by photographic illustrations.Conclusions: This paper describes and illustrates the gross appearances of FNA cytology samples of some commonly encountered lesions.

Objective: The study aimed to compare the utility of immunoflow cytometry (IFC) with two IgH polymerase chain reaction (PCR) methods for the identification of clonality in fine needle aspirations (FNAs) from T-cell-rich B-cell lymphomas (TCRBCLs).Methods: Ten cases of TCRBCLs were identified in which IFC had been performed according to our previously described method. Seven of these were cases in which the original diagnosis had been made by FNA cytology with IFC and cell block immunohistochemistry (IHC). The remaining three cases only had biopsies with histology, IFC and IHC. Formalin-fixed paraffin-embedded FNA cell block or histology tissue from these specimens had also been submitted for IgH PCR clonality studies using primers FR2a/VLJH and primers FR3a/VLJH. The results were reviewed and compared.Results: All 10 case demonstrated B-cell clonality for at least one of the primer sets on PCR, but none showed light chain restriction on IFC. All TCRBCLs were positive for CD20 and CD79a but negative for CD10 and BCl-2. They were also consistently negative for CD22, CD23, CD5, CD43, ALK-1, cyclin D1 and CD30.Conclusions: If IgH PCR clonality assays had a turnaround time of 1 or 2 days, there might be a strong case for these studies supporting or even replacing IFC, in the FNA diagnosis of lymphoid lesions.

Aims: To detect Simian virus 40 (SV40) DNA in mesotheliomas from New Zealand and from England using novel real time FRET probe polymerase chain reaction (PCR) protocols.Methods: Twenty four mesotheliomas from New Zealand ( Central North Island) and 32 mesotheliomas from England ( Greater Manchester region) were examined. Two real time FRET probe PCR protocols were optimised and their analytical sensitivity compared using dilutions of SV40 DNA. A conventional SV40 large tumour antigen protocol with detection by probe hybridisation and chemiluminescent Southern blotting was also optimised.Results: Both real time PCR protocols had the same analytical sensitivity, detecting down to 10(-6) pg of SV40 DNA for each reaction, approximately one SV40 copy. All of the 56 mesothelioma samples contained amplifiable beta globin DNA, but none contained amplifiable SV40 DNA with the conventional large T antigen PCR - Southern blotting protocol, or the two real time FRET probe PCR protocols. The positive and negative controls gave the expected results. There was no evidence of inhibition.Conclusions: There is abundant evidence in the literature for the presence of SV40 in mesotheliomas. However, this study found no evidence of SV40 in mesotheliomas from England and New Zealand. The extensive use of SV40 contaminated polio vaccine in New Zealand does not seem to have resulted in SV40 associated mesotheliomas.

AIMS:Fine needle aspiration (FNA) cytology is an accepted means of diagnosing and typing common forms of lymphoma, particularly small lymphocytic lymphoma, follicular lymphoma, and large B cell lymphoma. However, its usefulness for diagnosing less common forms of lymphoma is not clearly established and this study was designed to examine this.METHODS:The study reviewed the FNAs of suspected lymphomas collected over a period of approximately five years.RESULTS:FNA samples were available for 138 definite lymphomas; most were common forms of B cell lymphoma. However, there was also one Burkitt lymphoma (BL), two Burkitt-like large B cell lymphomas, 15 classic Hodgkin lymphomas (HLs), two nodular lymphocyte predominant Hodgkin lymphomas, four mantle cell lymphomas, two mediastinal (thymic) large B cell lymphomas (MLBCLs), 11 peripheral T cell lymphomas (PTCLs), and five T cell rich large B cell lymphomas (TCRLBCLs).CONCLUSIONS:FNA diagnosis of BL was possible with immunoflow cytometry (IFC), cell block immunohistochemistry (IHC), and cell block fluorescent in situ hybridisation for c-myc alteration. It was difficult to make a definite diagnosis of HL and MLBCL on FNA alone. Both tend to be sclerotic tumours and FNA tends to yield scanty neoplastic cells. The FNA diagnosis of PTCL depended on cell block IHC; IFC was not usually useful. TCRLBCL did not show light chain restriction on IFC of FNA samples, probably because of frequent reactive B cells in the tumour. Thus, HL, MLBCL, and TCRLBCL are often difficult to diagnose accurately on FNA cytology, even when using IFC and cell block IHC.