The 2023 Annual Review Issue of The Journal of Pathology, Recent Advances in Pathology, contains 12 invited reviews on topics of current interest in pathology. This year, our subjects include immuno-oncology and computational pathology approaches for diagnostic and research applications in human disease. Reviews on the tissue microenvironment include the effects of apoptotic cell-derived exosomes, how understanding the tumour microenvironment predicts prognosis, and the growing appreciation of the diverse functions of fibroblast subtypes in health and disease. We also include up-to-date reviews of modern aspects of the molecular basis of malignancies, and our final review covers new knowledge of vascular and lymphatic regeneration in cardiac disease. All of the reviews contained in this issue are written by expert groups of authors selected to discuss the recent progress in their particular fields and all articles are freely available online (https://pathsocjournals.onlinelibrary.wiley.com/journal/10969896). © 2023 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Graft-versus-host disease (GvHD) after liver transplantation (LT) occurs in 0.2–0.3% of liver transplant recipients. Each case is characterized by individual peculiarities of the clinical picture. There are no standards or clinical guidelines for the treatment of GvHD in solid organ recipients; mortality remains very high among these patients. We present two clinical cases of verified GvHD that developed early after LT, and we offer a brief review of the current state of the art in the study of this problem.

Abstract A total of 10,696 randomly selected sheep have been collected in two slaughterhouses in the north of Algeria (El Harrach and Boufarik) to determine the prevalence of muscular cysticercosis and macroscopic cysts of sarcosporidiosis, to find out the association between prevalence and potential risk factors, as well as to assess the distribution of these parasites in the surface’s muscles of slaughtered sheep. All of the slaughtered sheep carcasses were visually and carefully inspected. Cysticercosis and sarcosporidiosis were found in 220 (2.06 %) and 76 (0.7 %) sheep, respectively. For both diseases, the prevalence was significantly higher in females than males. The prevalence of Cysticercus ovis increased with age, and the difference was statistically significant (P < 0.0001), while all infected animals were old (over 5 years old) for sarcosporidiosis. For C. ovis, it didn’t have significant difference between the seasons, however, all sheep were infected in the spring for sarcosporidiosis. All the detected cysts of C. ovis were non-viable, and were more frequently detected in the heart (51.82 %), followed by the diaphragm (30.77 %) and the oesophagus (17.41 %). This anatomical distribution of C. ovis cysts showed a significant variation (P < 0.001) in different predilection sites. Whereas, for sarcosporidiosis, the species involved was identified as S. gigantea by histology and were distributed in the organs as follows: the skeletal muscles (38.15 %), the oesophagus (31.57 %) and the diaphragm (30.26 %); no significant difference were noted between the 3 sites. The present study has revealed that these parasites are present in Algeria. Appropriate control measures need to be introduced to eradicate these parasites in sheep.

The 2022 Annual Review Issue of The Journal of Pathology, Recent Advances in Pathology, contains 15 invited reviews on research areas of growing importance in pathology. This year, the articles include those that focus on digital pathology, employing modern imaging techniques and software to enable improved diagnostic and research applications to study human diseases. This subject area includes the ability to identify specific genetic alterations through the morphological changes they induce, as well as integrating digital and computational pathology with 'omics technologies. Other reviews in this issue include an updated evaluation of mutational patterns (mutation signatures) in cancer, the applications of lineage tracing in human tissues, and single cell sequencing technologies to uncover tumour evolution and tumour heterogeneity. The tissue microenvironment is covered in reviews specifically dealing with proteolytic control of epidermal differentiation, cancer-associated fibroblasts, field cancerisation, and host factors that determine tumour immunity. All of the reviews contained in this issue are the work of invited experts selected to discuss the considerable recent progress in their respective fields and are freely available online (https://onlinelibrary.wiley.com/journal/10969896). © 2022 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Histopathologic examination of highly pigmented melanoma tissues has always been a challenge for pathologists. The high concentration of melanin pigment is an obstacle for immunohistochemistry and the ensuing evaluation. Therefore, removing melanin has become a crucial step for processing heavily pigmented melanoma samples. Several bleaching techniques have been proposed in the past, however, the most commonly used methods are time-consuming and poorly standardized. In this study, we propose a new fast and fully automated bleaching method applicable to validated immunohistochemical panels already used in the diagnosis of melanocytic tumors. The proposed bleaching protocol is based on sample pretreatment with 0.5% hydrogen peroxide and a Tris base pH 10 solution for 8 minutes at 80°C before antigen retrieval. Immunohistochemistry with HMB45, MART-1, Ki-67, SOX10, S-100, Tyrosinase, and BRAF(V600E) antibodies showed that this pretreatment removed excess melanin without affecting the tissue antigenicity and cytoarchitecture. In conclusion, we propose a new fast and automated bleaching protocol, easily transferable to a routine setting with efficient results in specimens in which the melanin pigmentation could blunt the histopathologic examination.

To determine the concordance between the clinical diagnosis of women with abnormal vaginal discharge (AVD) and laboratory results using molecular detection and observation of the vaginal microbiota. Cross-sectional study conducted in 2018 in Temuco, Chile. A total of 25 midwives from 12 health centers participated. A total of 125 women > 18 years old, volunteers, were recruited. The sample of the posterior vaginal fornix was obtained by speculoscopy. Characteristics of the discharge and of the external and internal genitalia were observed. Gram staining was used to observe vaginal microbiota, blastoconidia and pseudohyphae, and polymerase chain reaction was used for the detection of Trichomonas vaginalis and Candida albicans. The Cohen kappa coefficient was used in the concordance analysis. Out of a total of 125 women with AVD, 85.6% consulted spontaneously and 14.4% were diagnosed clinically during a routine check-up. Absolute concordance was significant (p = 0.0012), with an agreement of 13.6%. The relative concordance was significant, but fair for bacterial vaginosis (Kappa = 0.21; p = 0.003) and candidiasis (Kappa = 0.22; p = 0.001), and slight for trichomoniasis (Kappa = 0.14; p = 0.009). The percentage of coincidence of the diagnoses (single or mixed) by laboratory and midwives was: bacterial vaginosis 63.2% (12/19), candidiasis 36.5% (27/74), and trichomoniasis 12.5% (4/32). There was 20% coinfection. A total of 36% of the clinical diagnoses of AVD had negative laboratory tests. The vulvovaginitis conditions candidiasis and trichomoniasis appear to be overdiagnosed, and bacterial vaginosis appears to be underdiagnosed by the clinical diagnosis when compared with the laboratory diagnosis. The low concordance obtained shows the importance of complementing the clinical diagnosis with a laboratory study of AVD, particularly in women with failed treatments and/or coinfections with unspecific and varying signs and symptoms.

Rapid on-site evaluation (ROSE) by cytopathologists during endoscopic ultrasound-fine-needle aspiration (EUS-FNA) of solid pancreatic lesions (SPLs) improves adequacy and diagnostic accuracy while reducing the number of needle passes. We evaluated the usefulness of ROSE performed by the endosonographer. Patients with an SPL were randomly assigned to EUS-FNA with ROSE or non-ROSE. Procedure duration, number of needle passes, specimen adequacy, and adverse event rates were compared. Sixty-five patients were enrolled (33 in the ROSE vs 32 in the non-ROSE group). Both groups were similar in terms of age, sex, size, and location of the lesion. Specimen adequacy rates were high and similar between groups. Mean (standard deviation) procedure duration was shorter in the ROSE versus non-ROSE group (30.0 [11.3] vs 37.0 [7.2] minutes, P < 0.005), as well as the mean (standard deviation) number of needle passes (2.6 [0.8] vs 3.5 [0.8], P < 0.005). Accuracy parameters as sensitivity and accuracy of ROSE by the endosonographer for malignancy were 93% and 88%, respectively. After specific training, the endosonographer can accurately evaluate samples during EUS-FNA of SPL, allowing for a shorter procedure duration and a lower number of needle passes.

The 2021 Annual Review Issue of The Journal of Pathology contains 14 invited reviews on current research areas of particular importance in pathology. The subjects included here reflect the broad range of interests covered by the journal, including both basic and applied research fields but always with the aim of improving our understanding of human disease. This year, our reviews encompass the huge impact of the COVID-19 pandemic, the development and application of biomarkers for immune checkpoint inhibitors, recent advances in multiplexing antigen/nucleic acid detection in situ, the use of genomics to aid drug discovery, organoid methodologies in research, the microbiome in cancer, the role of macrophage-stroma interactions in fibrosis, and TGF-β as a driver of fibrosis in multiple pathologies. Other reviews revisit the p53 field and its lack of clinical impact to date, dissect the genetics of mitochondrial diseases, summarise the cells of origin and genetics of sarcomagenesis, provide new data on the role of TRIM28 in tumour predisposition, review our current understanding of cancer stem cell niches, and the function and regulation of p63. The reviews are authored by experts in their field from academia and industry, and provide comprehensive updates of the chosen areas, in which there has been considerable recent progress. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Thymosin beta 4 (TB4) is the most abundant member of the beta-thymosin family in humans. The main physiological role of TB4 is the regulation of actin polymerization. TB4 is also involved in angiogenesis, cell survival, cell migration and fetal development. The aim of this study was to evaluate the activity of TB4 as a fetal growth promoter when administered during pregnancy. Our protocols have been carried out in full conformity with the rules and guidelines expected for this kind of trial. 10 pregnant mice received the same injection regimen. Only 6 of these 10 are part of this experiment because they were pregnant. At 10:00 a.m. on day E14 and E17 of gestation mice were weighed and treated with an intraperitoneal injection of TB4 (Regene RX, Rockville, MD, USA; 6 mg/kg in PBS). The mothers treated with TB4 for two days precisely E14 and E17, showed a higher cranio-caudal length when compared to control newborns. At histology, maternal TB4 treatment was associated with more advanced development of lungs, heart, kidney, cerebral cortex and notochord. Our study shows that TB4 administration during gestation may act as a powerful fetal growth promoter, by accelerating the development of newborn organs and tissues.