A Solitary Rosai-Dorfman Disease of The Talus: The First Case Report of Bisphosphonate Therapy with Imaging Follow-up

Rosai-Dorfman disease (RDD) manifesting as a solitary osseous lesion especially of talus bone is rare. The authors reported a 31-year-old Thai man who had chronic left ankle pain and the biopsy of his talar lesion demonstrated emperipolesis, the typical histological feature of RDD. He was treated with curettage and adjuvant bisphosphonate and appeared to show improvement in clinical symptoms and radiological evidence. To the authors’ knowledge, this is the first report of an intraosseous RDD lesion treated with bisphosphonate with imaging follow-up. Keywords: Rosai-Dorfman disease; Talus; Solitary; Radiology; Bisphosphonate

PATH-17. POSSIBLE ASSOCIATION BETWEEN OLIGODENDROGLIAL HISTOLOGICAL FEATURES OF IDHMUT/CODEL LOWER GRADE GLIOMAS AND PATIENT'S FAVORABLE PROGNOSIS, BUT NOT IN IDHMUT/NONCODEL AND IDH-WILDTYPE TUMORS

Comprehensive diagnostic using histological and molecular characteristics began to be implemented in WHO 2016 but the relevance of oligodendroglial histological features to patients’ prognoses is still controversial. To elucidate the connection between oligodroglial histology and patient’s prognoses we analyzed 93 LrGGs resected for about 2 decades were reassessed for histological features based on WHO2007 with special interest to pure oligodendroglial diagnosis (namely, oligodendroglioma or anaplastic oligodendroglioma) and presence of classic for oligodendroglioma (CFO) features. Those histological features, patients’ OS, and tumor chromosomal/genetic characteristics were correlated each other in each of the 3 IDH-1p/19q based molecular groups. The reassessed morphology-based diagnosis was shown to be most strict for astrocytic, but loosened for oligodendroglial tumors as compared with the original institutional diagnoses and WHO2016. The pure oligodendroglial diagnosis by reassessment was associated with longer OS in IDHmut/codel group, but not in IDHmut/noncodel and IDH-wildtype groups. The presence of CFO was not associated with patients’ OS in any molecular groups. Gain of 8q was associated with the oligodendroglial diagnosis in IDHmut/noncodel group. Neither the oligodendroglial diagnosis nor CFO was predictive for the methylation status of the MGMT gene in any of the 3 molecular groups. NGS of the IDHmut/codel tumors suggested that mutations in the FUBP1 and CIC genes might be associated with poor prognosis. The oligodendroglial histological feature is not independently predictive for either patients’ prognosis or chemotherapeutic response in LrGGs, except the oligodendroglial diagnosis in IDHmut/codel tumors.

A Rare Case of Canine Metastatic Spermatocytic Tumor without Sarcomatous and Anaplastic Variants

Spermatocytic tumor is a rare testicular tumor, which is originated from gonocytes. It is characterized by the histological feature of tripartite which is composed of large, medium, and lymphocyte-like small cells. It is well-known that spematocytic tumor is benign, thus a good prognosis is expected after simple resection. Metastatic spermatocytic tumor is extremely rare and usually accompanied by histological variants including sarcomatous changes and anaplastic variants. In this case, however, we report a canine metastatic spermatocytic tumor without prominent sarcomatous changes and anaplastic variants. The mass was composed of three kinds of cells including large, medium, and small cells with high pleomorphism. The neoplastic cells had an indistinct cytoplasmic border and mitotic figures were frequently observed. The primary spermatocytic tumor metastasized to the abdominal organs one month after the resection, and the dog died 13 months after the surgery. Thus, careful follow-up is recommended after surgical resection of canine spermatocytic tumor even though metastasis in spermatocytic tumors is rare.

P162 Microscopic inflammation in limited Ulcerative Colitis at diagnosis: can a single histological feature predict prognosis?

Background Histological assessment is becoming increasingly important in the management of Ulcerative Colitis (UC). The Nancy index (NI), a recently developed and validated score, has been shown to accurately represent histological inflammation and to correlate with prognosis. However, it is a composite score, involving the analysis of more than one histological feature, which may limit its applicability. Our aim was to evaluate if a single component of the NI could individually predict prognosis in limited UC (E1 and E2) patients. Methods Multi-centre retrospective cohort study of newly diagnosed, treatment-naïve proctitis and left-sided ulcerative colitis patients. Biopsies from inflamed rectal mucosa were reviewed by two pathologists. Histological features from the NI were selected for analysis, including presence of ulcers, acute inflammatory infiltrate (with separate evaluation of neutrophils in lamina propria and epithelium) and chronic inflammatory infiltrate. Mucin depletion and basal plasmacytosis were also evaluated. The primary outcome was a composite outcome intended to evaluate disease-related complications, including proximal disease extension, need for hospitalisation or colectomy. Survival analysis, including univariate and multivariate Cox-regression analysis was performed. Results A total of 91 patients were included (56.0% males, mean age 44±17 years, median follow-up 44 months [2–328]). Overall, 64.8% of the patients had proctitis (E1) and 35.2% left-sided colitis (E2). The most frequent histological features were the presence of chronic inflammatory infiltrate (93.4%), mucin depletion (81.3%) and basal plasmacytosis (78.0%). During the follow-up, 22.0% presented a disease-related complication. The NI was not able to predict prognosis (HR 3.09, 95% CI 0.71–13.36, p=0.132). In univariate analysis, the presence of neutrophils in the epithelium in more than 50% of the crypts was marginally significant for the primary outcome (HR 2.51, 95% CI 0.99–6.36, p=0.05). In multivariate analysis, after adjusting for gender, age at diagnosis, disease extent (E1 vs E2), Mayo endoscopic score (< 2 vs ≥ 2) and clinical severity at diagnosis (mild vs moderate to severe UC) this single component of the score was associated with the primary outcome (aHR 3.36, 95% IC 1.21–9.31, p=0.02). No other histological feature was able to individually predict prognosis (p>0.05). Conclusion The presence of neutrophils in the epithelium in more than 50% of the crypts in endoscopically inflamed mucosa at diagnosis was associated with higher disease complications in limited UC patients. The evaluation of a single feature could facilitate the use of histology in the prediction of prognosis in UC. Our results need to be prospectively validated.

Effect of coumestrol on the histological feature of ovary of pups of F1 generation delivered from exposed mothers at different days of gestation

Phytoestrogens are the plant substances, which are structurally and functionally similar to steroids and produce estrogenic effects. It is well established that phytoestrogens when administered orally caused remarkable effects on the reproductive organs in females. It is also known that female rats, which consume more phytoestrogen for longer period, suffer from sterility. In the present study, efforts have been made to assess the effect of coumestrol on reproductive organs when exposed in uteroin mother and its effects on the development of postnatal pups.The administration of coumestrol during different days of pregnancy induced remarkable changes in the histological features of ovary of female rats of F1generation even at the age of 6 months.

Hereditary Hypofibrinogenemia with Hepatic Storage

Fibrinogen is a 340-kDa plasma glycoprotein constituted by two sets of symmetrical trimers, each formed by the Aα, Bβ, and γ chains (respectively coded by the FGA, FGB, and FGG genes). Quantitative fibrinogen deficiencies (hypofibrinogenemia, afibrinogenemia) are rare congenital disorders characterized by low or unmeasurable plasma fibrinogen antigen levels. Their genetic basis is represented by mutations within the fibrinogen genes. To date, only eight mutations, all affecting a small region of the fibrinogen γ chain, have been reported to cause hereditary hypofibrinogenemia with hepatic storage (HHHS), a disorder characterized by protein aggregation in the endoplasmic reticulum, hypofibrinogenemia, and liver disease of variable severity. Here, we will briefly review the clinic characteristics of HHHS patients and the histological feature of their hepatic inclusions, and we will focus on the molecular genetic basis of this peculiar type of coagulopathy.

Deep learning enables pathologist-like scoring of NASH models

Non-alcoholic fatty liver disease (NAFLD) and the progressive form of non-alcoholic steatohepatitis (NASH) are diseases of major importance with a high unmet medical need. Efficacy studies on novel compounds to treat NAFLD/NASH using disease models are frequently evaluated using established histological feature scores on ballooning, inflammation, steatosis and fibrosis. These features are assessed by a trained pathologist using microscopy and assigned discrete scores. We demonstrate how to automate these scores with convolutional neural networks (CNNs). Whole slide images of stained liver sections are analyzed using two different scales with four CNNs, each specialized for one of four histopathological features. A continuous value is obtained to quantify the extent of each feature, which can be used directly to provide a high resolution readout. In addition, the continuous values can be mapped to obtain the established discrete pathologist-like scores. The automated deep learning-based scores show good agreement with the trainer - a human pathologist.

Healing Myocarditis from a Hypertrophied Heart with Multifocal Fibrosis Mimicking Cardiomyopathy

We report the case of an 18 year old man who unexpectedly died of healing myocarditis. His heart was hypertrophied with multifocal fibrosis which can be a common histological feature of primary and secondary cardiomyopathy as well as the healing phase of myocarditis. However, the pattern of myocardial fibrosis, inflammation with myonecrosis, sparing of the right ventricular myocardium, and cardiomyocytes features in the remaining areas of the heart were considered as the key elements in determining a diagnosis of myocarditis. This case illustrates that meticulous histologic examination and the analysis of the histologic findings in the hypertrophied heart with multifocal fibrosis can be helpful to make a correct diagnosis.

Apoptotic colopathy: a pragmatic approach to diagnosis

‘Apoptotic colopathy’ is an umbrella term signifying a pattern of injury where the gastrointestinal biopsy shows a colitic picture with apoptosis as the predominant histological feature. Although the entities within apoptotic colopathy share a common histological feature— ‘apoptosis’, there is a list of varied clinical differential diagnoses that produce this similar histological pattern of injury. These include graft-versus-host disease, drug-induced injury due to multiple drugs (in particular, mycophenolate mofetil, check point inhibitor therapy and some others), infections (particularly cytomegalovirus, adenovirus and some others), immune disorders and other miscellaneous causes. However, the management of these varied differentials is strikingly different, thus necessitating an algorithmic approach for accurate diagnosis and optimal patient management. A definitive diagnosis requires interpretation of varied histological findings in the appropriate clinical context including clinical history, drug history and laboratory findings. This review will focus on the histopathological findings of varied entities that can manifest as ‘apoptotic colopathy’ on assessment of colonic biopsies.