Journal of Pathology and Translational Medicine最新文献

Fibrin-associated large B-cell lymphoma (FA-LBCL) is an extremely rare subtype of LBCL that consists of microscopic aggregates of atypical large B cells in the background of fibrin. Here, we report the first case of FA-LBCL in Korea. A 57-year-old male presented with a large amount of thrombus in the thoracic aorta during follow-up for graft replacement of the thoracoabdominal aorta 8 years prior. The removed thrombus, measuring 4.3 × 3.1 cm, histologically exhibited eosinophilic fibrinous material with several small clusters of atypical lymphoid cells at the periphery. The atypical cells were positive for CD20 by immunohistochemistry and for Epstein-Barr virus by in situ hybridization. The Ki-67 proliferation rate was 85%. The patient was still alive with no recurrence at the 7-year follow-up after thrombectomy. Although the diagnosis can be very difficult and challenging due to its paucicellular features, pathologists should be aware of FALBCL, which has likely been underestimated in routine evaluations of thrombi.

Histopathologic criteria of usual interstitial pneumonia (UIP)/idiopathic pulmonary fibrosis (IPF) were defined over the years and endorsed by leading organizations decades after Dr. Averill A. Liebow first coined the term UIP in the 1960s as a distinct pathologic pattern of fibrotic interstitial lung disease. Novel technology and recent research on interstitial lung diseases with genetic component shed light on molecular pathogenesis of UIP/IPF. Two antifibrotic agents introduced in the mid-2010s opened a new era of therapeutic approaches to UIP/IPF, albeit contentious issues regarding their efficacy, side effects, and costs. Recently, the concept of progressive pulmonary fibrosis was introduced to acknowledge additional types of progressive fibrosing interstitial lung diseases with the clinical and pathologic phenotypes comparable to those of UIP/IPF. Likewise, some authors have proposed a paradigm shift by considering UIP as a stand-alone diagnostic entity to encompass other fibrosing interstitial lung diseases that manifest a relentless progression as in IPF. These trends signal a pendulum moving toward the tendency of lumping diagnoses, which poses a risk of obscuring potentially important information crucial to both clinical and research purposes. Recent advances in whole slide imaging for digital pathology and artificial intelligence technology could offer an unprecedented opportunity to enhance histopathologic evaluation of interstitial lung diseases. However, current clinical practice trends of moving away from surgical lung biopsies in interstitial lung disease patients may become a limiting factor in this endeavor as it would be difficult to build a large histopathologic database with correlative clinical data required for artificial intelligence models.

Primary leiomyosarcoma of the bone is rare. Histologically, it resembles leiomyosarcoma of soft tissue. Given the rarity of this entity, its diagnosis should be made only after clinical studies and workup have excluded metastasis from other sites. Herein, we describe an additional case of primary bone leiomyosarcoma. We report a 32-year-old female patient, who presented with right knee pain and was found to have a right distal femur mass by imaging studies. Biopsy showed a neoplasm composed of fascicles of spindle cells, arranged in different patterns, with significant pleomorphism. The tumor cells were positive for smooth muscle actin, focally positive for desmin and H-caldesmon. No other masses in the body were detected by imaging studies. The diagnosis of leiomyosarcoma of the bone was rendered. Given the broad diagnostic differential of primary bone leiomyosarcoma, it is important to be aware of this rare bone tumor phenotype and of its histomorphologic and immunohistochemical features for an accurate diagnosis.

Background: The implication of the presence of tumor-infiltrating T lymphocytes (TIL-T) in diffuse large B-cell lymphoma (DLBCL) is yet to be elucidated. We aimed to investigate the effect of TIL-T levels on the prognosis of patients with DLBCL.

Methods: Ninety-six patients with DLBCL were enrolled in the study. The TIL-T ratio was measured using QuPath, a digital pathology software package. The TIL-T ratio was investigated in three foci (highest, intermediate, and lowest) for each case, resulting in TIL-T-Max, TIL-T-Intermediate, and TIL-T-Min. The relationship between the TIL-T ratios and prognosis was investigated.

Results: When 19% was used as the cutoff value for TIL-T-Max, 72 (75.0%) and 24 (25.0%) patients had high and low TIL-T-Max, respectively. A high TIL-T-Max was significantly associated with lower serum lactate dehydrogenase levels (p < .001), with patient group who achieved complete remission after RCHOP therapy (p < .001), and a low-risk revised International Prognostic Index score (p < .001). Univariate analysis showed that patients with a low TIL-T-Max had a significantly worse prognosis in overall survival compared to those with a high TIL-T-Max (p < .001); this difference remained significant in a multivariate analysis with Cox proportional hazards (hazard ratio, 7.55; 95% confidence interval, 2.54 to 22.42; p < .001).

Conclusions: Patients with DLBCL with a high TIL-T-Max showed significantly better prognosis than those with a low TIL-T-Max, and the TIL-T-Max was an independent indicator of overall survival. These results suggest that evaluating TIL-T ratios using a digital pathology system is useful in predicting the prognosis of patients with DLBCL.

Background: Follicular tumors include follicular thyroid adenomas and carcinomas; however, it is difficult to distinguish between the two when the cytology or biopsy material is obtained from a portion of the tumor. The presence or absence of invasion in the resected material is used to differentiate between adenomas and carcinomas, which often results in the unnecessary removal of the adenomas. If nodules that may be follicular thyroid carcinomas are identified preoperatively, active surveillance of other nodules as adenomas is possible, which reduces the risk of surgical complications and the expenses incurred during medical treatment. Therefore, we aimed to identify biomarkers in the invasive subpopulation of follicular tumor cells.

Methods: We performed a spatial transcriptome analysis of a case of follicular thyroid carcinoma and examined the dynamics of CD74 expression in 36 cases.

Results: We identified a subpopulation in a region close to the invasive area, and this subpopulation expressed high levels of CD74. Immunohistochemically, CD74 was highly expressed in the invasive and peripheral areas of the tumor.

Conclusions: Although high CD74 expression has been reported in papillary and anaplastic thyroid carcinomas, it has not been analyzed in follicular thyroid carcinomas. Furthermore, the heterogeneity of CD74 expression in thyroid tumors has not yet been reported. The CD74-positive subpopulation identified in this study may be useful in predicting invasion of follicular thyroid carcinomas.

The 5th edition WHO Classification of Urinary and Male Genital Tumours (2022) introduced many significant changes relevant to urologic daily practice, mainly to renal tumors which was covered in the What's New newsletter in September 2022. In this newsletter, we summarize the notable changes to bladder, prostate, testis, and penis based on the 5th edition of the WHO.

Background: Anaplastic lymphoma kinase (ALK) mutations have been identified as a prominent cause of some familial and sporadic neuroblastoma (NB). ALK expression in NB and its relationship with clinical and histopathological features remains controversial. This study investigated ALK expression and its potential relations with these features in NB.

Methods: Ninety cases of NB at the Department of Pathology, University of Medicine and Pharmacy at Ho Chi Minh City, Viet Nam from 01/01/2018 to 12/31/2021, were immunohistochemically stained with ALK (D5F3) antibody. The ALK expression and its relations with some clinical and histopathological features were investigated.

Results: The rate of ALK expression in NB was 91.1%. High ALK expression (over 50% of tumor cells were positive with moderate-strong intensity) accounted for 65.6%, and low ALK expression accounted for 34.4%. All the MYCN-amplified NB patients had ALK immunohistochemistry positivity, most cases had high ALK protein expression. The undifferentiated subtype of NB had a lower ALK-positive rate than the poorly differentiated and differentiated subtype. The percentages of ALK positivity were significantly higher in more differentiated histological types of NB (p = .024). There was no relation between ALK expression and: age group, sex, primary tumor location, tumor stage, MYCN status, clinical risk, Mitotic-Karyorrhectic Index, prognostic group, necrosis, and calcification.

Conclusions: ALK was highly expressed in NB. ALK expression was not related to several clinical and histopathological features. More studies are needed to elucidate the association between ALK expression and ALK gene status and to investigate disease progression, especially the oncogenesis of ALK-positive NB.

The 5th edition WHO Classification of Skin Tumors (2022) has introduced changes to nomenclature and diagnostics. Important differences are discussed below. Changes in each category of skin tumor have been detailed, with particular emphasis on meaningful advances in our understanding of the molecular pathogenesis of the skin's diverse tumor landscape.