Pathology International最新文献

Helicobacter pylori is the main pathogenic factor in gastric cancer (GC), and the interleukin (IL)-17-mediated inflammatory response plays a crucial role in both H. pylori infection and gastric carcinogenesis. CMTM4, a subunit of the IL-17 receptor (IL-17R), has been implicated in immune responses, but its role in GC development remains unclear. In this study, we investigate the role of CMTM4 during H. pylori-induced gastric carcinogenesis using Cmtm4 knockout (KO) mice. Our findings indicated that Cmtm4 deficiency inhibited GC development and pseudopyloric metaplasia, while reducing DNA damage in the gastric mucosa. Mechanistically, Cmtm4 deletion downregulated the IL-17 signaling pathway in GC. Specifically, it suppressed the expression of IL-17 receptor RC (IL-17RC) and its downstream signaling molecules, resulting in the inhibition of nuclear factor-κ B (NF-κB) activation and a decrease in NADPH oxidase-1 (NOX1) levels. These results suggest that Cmtm4 deletion suppresses H. pylori-induced gastric carcinogenesis and precancerous lesion formation, potentially through the regulation of IL-17RC/NF-κB/NOX1 signaling, which may represent a new target for the early prevention of GC.

Artificial intelligence (AI) is an emerging tool in diagnostic pathology, including prostate pathology. This review summarizes the possibilities offered by AI and also discusses the challenges and risks. AI has the potential to assist in the diagnosis and grading of prostate cancer. Diagnostic safety can be enhanced by avoiding the accidental underdiagnosis of small lesions. Another possible benefit is a greater degree of standardization of grading. AI for clinical use needs to be trained on large, high-quality data sets that have been assessed by experienced pathologists. A problem with the use of AI in prostate pathology is the plethora of benign mimics of prostate cancer and morphological variants of cancer that are too unusual to allow sufficient training of AI. AI systems need to be able to account for variations in local routines for cutting, staining, and scanning of slides. We also need to be aware of the risk that users will rely too much on the output of an AI system, leading to diagnostic errors and loss of clinical competence. The reporting pathologist must ultimately be responsible for accepting or rejecting the diagnosis proposed by AI.

Follicular dendritic cell sarcoma (FDCS) is a rare malignant neoplasm of follicular dendritic cell origin. It is occasionally associated with unicentric Castleman disease (UCD), particularly the hyaline-vascular (HV) variant (HV-UCD). We report a 56-year-old woman with FDCS arising in the parapharyngeal space in the background of HV-UCD. The patient presented with a painless right neck mass and extensive cervical lymphadenopathy without systemic symptoms. Surgical resection of the parapharyngeal mass revealed FDCS in the lymph nodes with features of HV-UCD. Immunohistochemistry confirmed the follicular dendritic cell lineage of the lesional cells, with positivity for CD21 and CD23. Subsequent lymph node dissection from levels 2A, 2B, 3, and 4 showed features of HV-UCD without residual FDCS. This case highlights the diagnostic challenge FDCS represents, particularly when arising in an unusual location. While complete surgical excision remains the standard of care, long-term follow-up is necessary to monitor for recurrence or metastasis.

We present a case of pancreatic ductal carcinoma with a microcystic appearance. A 64-year-old woman was found to have a pancreatic mass during a routine medical checkup. The tumor was well-circumscribed and multicystic; thus, she was followed up for suspected serous cystadenoma. However, the tumor gradually enlarged in the following 2.5 years; subsequently, she underwent a Whipple procedure. Grossly, the cut surface of the tumor was honeycomb-like with small cysts. Histologically, the cysts were ductal structures lined by a relatively bland, cuboidal or columnar epithelium with mildly enlarged nuclei. No intracytoplasmic mucus was observed. The presence of stromal invasion confirmed the diagnosis of ductal carcinoma. KRAS was wild type. Postoperative course was uneventful, with no recurrence to date (followup period: 5.5 years postsurgery). The present case did not meet any known subtypes of pancreatic ductal carcinoma. The tumor resembled a large duct variant, which typically shows a microcystic appearance. However, unlike the present case, the large duct type usually consists of mucus-rich neoplastic cells. A recent study on cholangiocarcinoma proposed a novel tubulocystic subtype characterized by microcystic neoplastic glands and adenofibromatous stroma, which is morphologically similar to the present case. The present case may correspond to a pancreatic counterpart of tubulocystic cholangiocarcinoma.

Although aortic valvular disease has various etiologies, recently, calcific aortic valve stenosis has been increasing. We analyzed the trends in the pathological characteristics of aortic valvular disease in the past four decades in Japan. The pathology department data for aortic valvular disease operated in our hospital documented 4508 patients from 1978 to 2022. Subsequently, trend analyses were performed over four periods: Period 1, 1978-1989 (618 cases); Period 2, 1990-1999 (903 cases); Period 3, 2000-2010 (1179 cases); and Period 4, 2011-2022 (1808 cases). We reviewed the pathological characterization of the resected aortic valves and categorized them based on the representative etiology of aortic valvular disease as congenital bicuspid, chronic rheumatic change, infective endocarditis, degenerative calcific change, and myxoid change. Our pathologic analysis revealed a significant decrease in the proportion of chronic rheumatic disease from 47% to 14%, an increase in the congenital bicuspid valve from 8% to 24%, and a rise of the degenerative calcific change of the aortic valve from 4% to 27% (p < 0.001), especially significant increases in aortic stenosis. Calcification of the aortic valve may result from an active process similar to atherosclerosis, leading to aortic stenosis with increasing dyslipidemia in Japanese patients in 40 years.

The reliability of Ki67-labeling index (LI) in core needle biopsy (CNB) of ER+/HER2- invasive breast carcinoma (IBC) and factors affecting the discordance of Ki67-LI between CNB and surgical resection (SR) remain unsolved. We aimed to elucidate factors influencing the discordance of Ki67-LI between CNB and SR to classify ER+/HER2- IBC into luminal A-like (LumA) and luminal B-like (LumB). The cohort included 326 ER+/HER2- IBCs available with Ki67-LI data at both CNB and SR specimens. Survival analysis was performed on 122 patients. Spearman's rank correlation coefficient of Ki67-LI between them was 0.683. The log-rank test showed that patients with ER+/HER2- IBC with ≥ 20% Ki67-LI at CNB (p < 0.001) and SR specimens (p < 0.001) had significantly shorter disease-free survival. In multivariate analysis, a negative PgR (p = 0.002) and > 2 cm pathological tumor size (p < 0.001) had the most significant effect on the discordance of Ki67-LI between CNB and SR at 20% and 30% cutoffs, respectively. Histological grade III had a significant effect on the concordance between them (p = 0.01) at 20% cutoff. Ki67-LI assessment in CNB may be useful for classifying ER+/HER2- IBC into LumA and LumB with caution of some prognostic factors and cutoffs.