ABSTRACT
Recent advances in artificial intelligence (AI) have provided novel tools for rapid and precise pathologic diagnosis. The introduction of digital pathology has enabled the acquisition of scanned slide images that are essential for the application of AI. The application of AI for improved pathologic diagnosis includes the error-free detection of potentially negligible lesions, such as a minute focus of metastatic tumor cells in lymph nodes, the accurate diagnosis of potentially controversial histologic findings, such as very well-differentiated carcinomas mimicking normal epithelial tissues, and the pathological subtyping of the cancers. Additionally, the utilization of AI algorithms enables the precise decision of the score of immunohistochemical markers for targeted therapies, such as human epidermal growth factor receptor 2 and programmed death-ligand 1. Studies have revealed that AI assistance can reduce the discordance of interpretation between pathologists and more accurately predict clinical outcomes. Several approaches have been employed to develop novel biomarkers from histologic images using AI. Moreover, AI-assisted analysis of the cancer microenvironment showed that the distribution of tumor-infiltrating lymphocytes was related to the response to the immune checkpoint inhibitor therapy, emphasizing its value as a biomarker. As numerous studies have demonstrated the significance of AI-assisted interpretation and biomarker development, the AI-based approach will advance diagnostic pathology.
ABSTRACT
Although most cerebral aneurysms are considered as acquired degenerative lesions, diverse anatomical variations in the circle of Willis have been encountered, some of which may play an important role in lesion hemodynamics and pathogenesis. The coalescence of the small vascular plexus to form the anterior communicating artery at the 6-7-week embryological stage may lead to developmental variations, such as fenestration and duplication. Herein, we report a rare anatomical variant of the anterior communicating artery that was concomitantly identified with a ruptured aneurysm. Both the right and left anterior cerebral arteries were connected by three anterior communicating arteries. A vertical segmental artery was present and connected the two anterior communicating arteries, forming an H-shape or plexiform structure. Furthermore, a 0.6×0.4 cm-sized saccular aneurysm with antero-inferior projection was present in the middle anterior communicating artery. The combination of triplication and H-shape in the present case was compared to previously reported anatomical variants.
ABSTRACT
We present an autopsy case of a 19-year-old man with a history of epilepsy whose unwitnessed sudden death occurred unexpectedly in the night. About 4 years before death, he was diagnosed with unilateral optic neuritis (ON). Demyelinating disease was suspected, but he was lost to follow up after the recovery. Six months before death, he received a second dose of mRNA coronavirus disease 2019 (COVID-19) vaccine. Three months before death, he experienced epileptic seizures for the first time. Seventeen days before death, he was infected with COVID-19, which showed self-limited course under home isolation. Several days before death, he complained of seizures again at night. Autopsy revealed multifocal gray-tan discoloration in the cerebrum. Histologically, the lesions consisted of active and inactive demyelinated plaques in the perivenous area of the white matter. Perivascular lymphocytic infiltration and microglial cell proliferation were observed in both white matter and cortex. The other major organs including heart and lung were unremarkable. Based on the antemortem history and postmortem findings, the cause of death was determined to be multiple sclerosis with suspected exacerbation. The direct or indirect involvement of cortex and deep gray matter by exacerbated multiple sclerosis may explain the occurrence of seizures. Considering the absence of other structural abnormalities except the inflammatory demyelination of the cerebrum, fatal arrhythmia or laryngospasm in the terminal epileptic seizure may explain his sudden unexpected death in the benign circumstances. In this case, the onset of seizure was preceded by COVID-19 vaccination, and the exacerbation of seizure was preceded by COVID-19 infection, respectively. Literature reporting first manifestation or relapse of multiple sclerosis temporally associated with COVID-19 vaccination or infection are reviewed.
ABSTRACT
We present autopsy findings of a 22-year-old man who developed chest pain 5 days after the first dose of the BNT162b2 mRNA vaccine and died 7 hours later. Histological examination of the heart revealed isolated atrial myocarditis, with neutrophil and histiocyte predominance.Immunohistochemical C4d staining revealed scattered single-cell necrosis of myocytes which was not accompanied by inflammatory infiltrates. Extensive contraction band necrosis was observed in the atria and ventricles. There was no evidence of microthrombosis or infection in the heart and other organs. The primary cause of death was determined to be myocarditis, causally-associated with the BNT162b2 vaccine.
ABSTRACT
We present autopsy findings of a 22-year-old man who developed chest pain 5 days after the first dose of the BNT162b2 mRNA vaccine and died 7 hours later. Histological examination of the heart revealed isolated atrial myocarditis, with neutrophil and histiocyte predominance.Immunohistochemical C4d staining revealed scattered single-cell necrosis of myocytes which was not accompanied by inflammatory infiltrates. Extensive contraction band necrosis was observed in the atria and ventricles. There was no evidence of microthrombosis or infection in the heart and other organs. The primary cause of death was determined to be myocarditis, causally-associated with the BNT162b2 vaccine.
ABSTRACT
Salivary gland tumors are histologically diverse, and each entity has distinctive histopathological and molecular features. We report two cases of salivary gland tumors with unique histological and molecular findings, which have not been documented previously. The tumors were located in the base of the tongue in both patients. Most tumor cells were arranged in cords and nests, giving a trabecularlike appearance. Focally, glandular structures with intraluminal mucin and perivascular pseudorosette-like configurations were identified. Tumor cells had eosinophilic to clear cytoplasm, and showed mild nuclear atypia. They were positive for pancytokeratin and negative for S-100, p63, c-KIT, androgen receptor, and neuroendocrine markers. Multiple foci of capsular or lymphovascular invasion were identified, but the Ki-67 labeling index was low (< 5%). Fluorescence in situ hybridization revealed concurrent alterations of MAML2 and EWSR1 gene. Further investigations with a larger number of cases with similar histological and molecular features will accurately classify this tumor.
ABSTRACT
Hypoplastic coronary artery disease (HCAD) is a rare congenital abnormality characterized by underdevelopment of one or more major branches of the coronary arteries, which may lead to myocardial infarction and sudden death. We report a case of HCAD that was incidentally detected during autopsy in a 25-year-old male soldier who died during underwater escape training. On macroscopic examination, the right coronary artery measured 1 mm in diameter, which was significantly smaller than that of other coronary arteries. We observed no anomalies in addition to HCAD. Death was attributed to drowning, which was consistent with autopsy findings and the circumstances of death. Although extremely rare, if sudden cardiac death is suspected in children and young adults, it must be confirmed through careful evaluation.
ABSTRACT
The musculoskeletal system can be involved as an extra-intestinal manifestation of inflammatory bowel disease. Among these, myositis in ulcerative colitis (UC) is very rare. A 14-year-old girl was admitted due to severe shoulder tenderness. She had complained of left jaw pain and swelling for the past 10 days. Inflammatory markers were elevated with no evidence of infectious etiology. Myositis was suspected by shoulder magnetic resonance imaging. Three days after admission, she developed hematochezia. Muscle biopsy and colonoscopy was performed due to worsening left mandibular area pain and persistent hematochezia. Colonoscopy showed consistent findings with UC. She was finally diagnosed with UC with myositis as an extra-intestinal manifestation. She showed a dramatic response to UC treatment. Gastrointestinal symptoms were well-controlled. After 14 months, UC symptoms and muscle pain were aggravated, which were relieved after steroid and cyclosporin treatment. We report a unique case of UC initially presented with myositis, preceding gastrointestinal symptoms.
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Purpose@#Recently, the 8th edition staging system of the American Joint Committee on Cancer (AJCC) for hepatocellular carcinoma (HCC) was released, including a change in T category. We aimed to validate the new AJCC system. @*Materials and Methods@#The predictive value of the new AJCC was validated in comparison to the previous edition, in a total 1,008 patients who underwent curative resection for HCC as initial treatment. @*Results@#The 2-year area under the curve values for recurrence-free survival (RFS) and overall survival (OS) were comparable in the 7th and 8th editions. Stage migration was observed in 63 patients (6.3%); from T2 to T1a for 44 patients and from T3 to T4 for 19 patients. The RFS and OS were not different between T1a and T1b in the 8th edition. For solitary tumors ≤ 2 cm, those with microvascular invasion had lower RFS and OS values than those without although they were all classified as T1a in the 8th edition. Tumors involving a major branch of the portal or hepatic vein (T4 by the 8th edition and T3b by the 7th edition) had shorter RFS and OS than multifocal tumors, at least one of which was > 5 cm (T3 by the 8th edition and T3a by the 7th edition). @*Conclusion@#The AJCC 8th edition staging system for HCC showed comparable predictive performance to the 7th edition. It is desirable in a future revision to consider sub-stratification of solitary tumors ≤ 2 cm (T1a) depending on the presence of vascular invasion, which is not included in the 8th edition.
ABSTRACT
IgG4-related disease is a systemic inflammatory disease and is known as IgG4-related lung disease (IgG4-RLD) when it involves the respiratory system. Primary lung cancer arising from a background of IgG4-RLD is very rare. Herein, we report a case of adenosquamous carcinoma arising from the background of IgG4-RLD and presenting as an interstitial lung disease pattern. A 66-year-old man underwent lobectomy under the impression of primary lung cancer. Grossly, the mass was ill-defined and gray-tan colored, and the background lung was fibrotic. Microscopically, tumor cells showed both squamous and glandular differentiation. Dense lymphoplasmacytic infiltration with fibrosis and obliterative phlebitis were seen in the background lung. IgG4 immunohistochemical stain showed diffuse positivity in infiltrating plasma cells. Primary lung adenosquamous carcinoma has not been reported in a background of IgG4-RLD. Due to the rarity of IgG4-RLD, physicians must follow patients with IgG4-RLD over long periods of time to accurately predict the risk of lung cancer.
Subject(s)
Aged , Humans , Carcinoma, Adenosquamous , Fibrosis , Immunoglobulin G , Lung Diseases , Lung Diseases, Interstitial , Lung Neoplasms , Lung , Phlebitis , Plasma Cells , Respiratory SystemABSTRACT
Cytologic diagnosis of nuclear protein in testis (NUT) midline carcinoma (NMC) is important due to its aggressive behavior and miserable prognosis. Early diagnosis of NMC can facilitate proper management, and here we report two rare cases of thoracic NMC with cytohistologic correlation. In aspiration cytology, the tumor presented with mixed cohesive clusters and dispersed single cells, diffuse background necrosis and many neutrophils. Most of the tumor cells had scanty cytoplasm and medium-sized irregular nuclei, which had fine to granular nuclear chromatin. Interestingly, a few dyskeratotic cells or squamoid cell clusters were present in each case. Biopsy specimen histology revealed more frequent squamous differentiation, and additional immunohistochemistry tests showed nuclear expression of NUT. Because this tumor has a notorious progression and has been previously underestimated in terms of its prevalence, awareness of characteristic findings and proper ancillary tests should be considered in all suspicious cases.
Subject(s)
Biopsy , Chromatin , Cytoplasm , Diagnosis , Early Diagnosis , Immunohistochemistry , Lung , Necrosis , Neutrophils , Nuclear Proteins , Nuts , Prevalence , Prognosis , TestisABSTRACT
BACKGROUND: Pulmonary nodular lymphoid hyperplasia (PNLH) is a non-neoplastic pulmonary lymphoid disorder that can be mistaken for malignancy on radiography. Herein, we present nine cases of PNLH, emphasizing clinicoradiological findings and histological features. METHODS: We analyzed radiological and clinicopathological features from the electronic medical records of nine patients (eight females and one male) diagnosed with PNLH. IgG and IgG4 immunohistochemical staining was performed in three patients. RESULTS: Two of the nine patients had experienced tuberculosis 40 and 30 years prior, respectively. Interestingly, none were current smokers, although two were ex-smokers. Three patients complaining of persistent cough underwent computed tomography of the chest. PNLH was incidentally discovered in five patients during examination for other reasons. The remaining patient was diagnosed with the disease following treatment for pneumonia. Imaging studies revealed consolidation or a mass-like lesion in eight patients. First impressions included invasive adenocarcinoma and mucosal-associated lymphoid tissue‒type lymphoma. Aspergillosis was suspected in the remaining patient based on radiological images. Resection was performed in all patients. Microscopically, the lesions consisted of nodular proliferation of reactive germinal centers accompanied by infiltration of neutrophils and macrophages in various degrees and surrounding fibrosis. Ultimately, all nine patients were diagnosed with PNLH and showed no evidence of recurrence on follow-up. CONCLUSIONS: PNLH is an uncommon but distinct entity with a benign nature, and understanding the radiological and clinicopathological characteristics of PNLH is important.
Subject(s)
Female , Humans , Adenocarcinoma , Aspergillosis , Cough , Electronic Health Records , Fibrosis , Follow-Up Studies , Germinal Center , Hyperplasia , Immunoglobulin G , Lymphoma , Macrophages , Neutrophils , Pneumonia , Pseudolymphoma , Radiography , Recurrence , Thorax , TuberculosisABSTRACT
OBJECTIVE: The objective of this study was to determine relationship between alteration of expression of E-cadherin, beta-catenin and tumor progression, clinical stage, lymph node metastasis, age of patients with uterine cervical cancer. METHODS: The authors evaluated the immunohistochemical expression pattern of E-cadherin and beta- catenin in relationship with tumor stage and clinicopathologic parameters in 71 cervical neoplasia including 36 cases of squamous cell carcinoma (SCC), 10 cases of microinvasive SCC, 22 cases of squamous cell carcinoma in situ, and 3 cases of severe dysplasia. RESULTS: There were aberrant expression in 76.1% of E-cadherin (54 of 71) and 74.6% of beta-catenin (53 of 71) in the cervical cancer. There was positive correlation of aberrant expression of E-cadherin with tumor progression and clinical stage (<0.005). There was positive correlation of aberrant expression of beta- catenin with tumor progression and clinical stage (<0.005). CONCLUSION: These results suggest that the degree or the pattern of E-cadherin, beta-catenin, and E-cadherin/beta-catenin complex may be related to histologic grade and clinical stage of uterine cervical cancer.