Topographical Anatomy of the Distal Ulna Attachment of the Radioulnar Ligament.

PURPOSE: The deep component of the distal radioulnar ligament provides translational stability and rotational guidance to the forearm. However, controversy exists regarding the importance of this structure as well as the nature of its attachment to the distal ulna. We aimed to evaluate the topographic anatomy of the distal ulna attachment of both the superficial and the deep components of the radioulnar ligament and to assess the relationship between its internal and its external morphometry. METHODS: Thirteen human distal ulnae attached by ulnar part of the distal radioulnar ligament were scanned using micro-computed tomography and reconstructed in 3 dimensions. In addition, the distal radioulnar ligaments were examined under polarized light microscopy to determine the histological characteristics of collagen contained within the ligaments. RESULTS: The deep limbs have broad marginal insertions at the fovea, whereas the superficial limbs have a circular and condensed insertion to the ulnar styloid. The center of the deep limb was separated from the base of the ulnar styloid by a mean of 2.0 ± 0.76 mm, and this distance was positively correlated with the width of the ulnar styloid. The mean distance between the center of the ulnar head and the center of the fovea was 2.4 ± 0.58 mm. The proportion of collagen type I was lower in the deep limb than in the superficial limb. CONCLUSIONS: This new observation of the footprint of the radioulnar ligament in the distal ulna indicates that the deep limb may serve as an internal capsular ligament of the distal radioulnar joint, whereas the superficial limb as the external ligament. CLINICAL RELEVANCE: Knowledge of the topographic anatomy of the radioulnar ligament's attachment to the distal ulna may provide a better understanding of distal radioulnar ligament-related pathologies.

Restoration of the central slip in congenital form of boutonniere deformity: case report.

We present a case of a congenital form of a boutonniere deformity involving both little fingers with a poorly differentiated extensor mechanism and the absence of the tendinous attachment on the dorsal aspect of the middle phalanx. This complex deformity was evaluated histologically followed by successful reconstruction of the central slip.

Intrathyroidal metastasis of tonsillar squamous cell carcinoma masquerading as a primary thyroid tumor.

Intrathyroidal metastasis of tonsillar squamous cell carcinoma is rare. To date, only six cases have been reported in the literature. This case was unusual and presented with thyromegaly before the diagnosis of the primary tumor. A 55-year-old male patient was suspected to have a primary thyroid tumor with nodal metastasis. The thyroid gland was diffusely enlarged, with no discernible mass. Histologically, the thyroid parenchyma revealed extensive endolymphatic tumor emboli, which were positive for p40 and p16 in a background of chronic lymphocytic thyroiditis. Positron emission tomography-computed tomography revealed hypermetabolic activity in the right tonsillar region. Tonsillar biopsy revealed human papillomavirus-positive squamous cell carcinoma. The present case is the first reported case of intrathyroidal metastasis of tonsillar squamous cell carcinoma with an initial clinical presentation of thyroid enlargement before the primary tumor of tonsillar cancer was diagnosed.

Metallic implant-associated lymphoma: ALK-negative anaplastic large cell lymphoma associated with total knee replacement arthroplasty.

Metallic implant-associated lymphomas are extremely rare. Only seven cases have been reported in association with knee joint arthroplasty, and all tumors were large B-cell lymphomas. This report is the first case of anaplastic large cell lymphoma occurring after total knee replacement arthroplasty. An 80­year­old female patient was admitted because of right knee pain for 2 years. She had undergone total knee replacement arthroplasty 10 years prior. Computed tomography showed an irregular osteolytic lesion in the right lateral femoral condyle, adjacent to the metallic prosthesis. Histologic findings reveal sheets of anaplastic tumor cells that were positive for CD2, CD4, CD5, CD43, and CD30 but negative for CD3, CD20, CD15, and anaplastic lymphoma kinase. Epstein-Barr encoding region in situ hybridization was negative. Analysis of T-cell receptor γ gene rearrangement studies using BIOMED-2-based multiplex polymerase chain reaction confirmed monoclonal T cell proliferation. The woman was finally diagnosed with ALK-negative anaplastic large cell lymphoma.

Deep Learning for the Pathologic Diagnosis of Hepatocellular Carcinoma, Cholangiocarcinoma, and Metastatic Colorectal Cancer.

Diagnosing primary liver cancers, particularly hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC), is a challenging and labor-intensive process, even for experts, and secondary liver cancers further complicate the diagnosis. Artificial intelligence (AI) offers promising solutions to these diagnostic challenges by facilitating the histopathological classification of tumors using digital whole slide images (WSIs). This study aimed to develop a deep learning model for distinguishing HCC, CC, and metastatic colorectal cancer (mCRC) using histopathological images and to discuss its clinical implications. The WSIs from HCC, CC, and mCRC were used to train the classifiers. For normal/tumor classification, the areas under the curve (AUCs) were 0.989, 0.988, and 0.991 for HCC, CC, and mCRC, respectively. Using proper tumor tissues, the HCC/other cancer type classifier was trained to effectively distinguish HCC from CC and mCRC, with a concatenated AUC of 0.998. Subsequently, the CC/mCRC classifier differentiated CC from mCRC with a concatenated AUC of 0.995. However, testing on an external dataset revealed that the HCC/other cancer type classifier underperformed with an AUC of 0.745. After combining the original training datasets with external datasets and retraining, the classification drastically improved, all achieving AUCs of 1.000. Although these results are promising and offer crucial insights into liver cancer, further research is required for model refinement and validation.

Extraintestinal migration of Centrorhynchus sp. (Acanthocephala: Centrorhynchidae) in experimentally infected rats.

Reptiles were known to serve as paratenic hosts for Centrorhynchus (Acanthocephala: Centrorhynchidae) in Korea, but the infection course in experimental animals was not elucidated yet. In this study, the tiger keelback snakes (Rhabdophis tigrinus) were collected and digested with artificial pepsin solution, and the larvae of Centrorhynchus were recovered from them. Then, the collected larvae were orally infected to rats for developmental observations. In rats, all the larvae were observed outside the intestine on day 3 post-infection (PI), including the mesentery and abdominal muscles. As for the development in rats, the ovary of Centrorhynchus sp. was observed at day 15 PI, and the cement glands were 3 in number. Based on the morphological characteristics, including the arrangement of proboscis hooks, these larvae proved to be a species of Centrorhynchus, and more studies were needed for species identification.

Molecular subtypes of triple-negative breast cancer: understanding of subtype categories and clinical implication.

BACKGROUND: Triple-negative breast cancer (TNBC) is a heterogeneous entity that encompasses several subtypes with distinct molecular characteristics. The patients with TNBCs show unpredictable response to the chemotherapy, and further there is the lack of effective agents. Thus, many studies have been underway to discover targeted therapy suitable for patients with specific genetic alterations in each molecular subtypes. TNBCs are classified as four major molecular subtypes according to the gene expression patterns. These are luminal androgen receptor (LAR), mesenchymal-like, immunomodulatory (IM), and basal-like types. CONCLUSION: Here, we discuss the unique molecular features of each subtype as well as promising targets for anti-cancer therapy.

A nasal myiasis in a 76-year-old female in Korea.

On July 2009, 5 fly larvae were discovered inside the nose of a 76-year-old female. She was living in Cheonan-si, and in a state of coma due to rupture of an aortic aneurysm. Surgery was performed on the day of admission, and the larvae were found 4 days later. By observing their posterior spiracle, the larvae were identified as Lucilia sericata. Considering the rapid development of this species, the infection was likely acquired during hospitalization. Further investigation on the hospital environment should be needed to know the origin of the infection.

A spindle cell predominant pancreatic solid-pseudopapillary tumor.

A hitherto unrecognized variant of solid-pseudopapillary tumor (SPT) of the pancreas is reported. The tumor presented in the pancreatic tail of a 44-year-old female patient. It was a well-defined, solid nodule measuring 25 mm in diameter, with homogenous tan gray cut surface. Histologically, the neoplasm was mostly composed of sheets of spindle cells. No cellular atypia and mitosis was identified. The periphery of the tumor showed typical feature of SPT. Immunohistochemically, the tumor cells were positive for vimentin, CD10, CD56, beta-catenin, and alpha1-antichymotrypsin, but negative for cytokeratin, chromogranin, synaptophysin and S-100 protein. Ultrastructurally, the tumor showed a few acinar spaces with microvilli between tumor cells. This case is peculiar in that the tumor did not show gross cystic change and predominantly consists of spindle shaped tumor cells, so may cause difficult diagnostic problem.

Pure choriocarcinoma of testis with tumor-infiltrating lymphocytes and granulomas.

Pure choriocarcinoma is very rare in the testes, and host immune responses including tumor infiltrating lymphocytes are unusual in choriocarcinoma. This study reports a case of pure testicular choriocarcinoma with extensive lymphocytic infiltrate and granulomatous inflammation. Scrotal ultrasonography revealed a heterogeneous, hyperechoic intratesticular mass. -human chorionic gonadotropin levels were elevated in a radioimmunoassay. The hemorrhagic and necrotic solid mass was composed of two cell populations - mononuclear pleomorphic cells and intimately admixed multinucleated smudged cells. The tumor cells were positive for cytokeratin 7, epidermal growth factor receptors, human placental lactogen and p57. Many inflammatory cells were present within the tumor. The majority of infiltrating cells were CD8-positive cytotoxic cells, which also expressed granzyme-B and TIA-1. The tumor cells were positive for FasL, but negative for Fas. Therefore, this case seemed to escape the host defense response to the tumor due to the loss of Fas, although the cellular host immune response was still active.

Expression pattern of programmed death-1 in lymphocyte-rich classical Hodgkin lymphoma according to the growth patterns.

We present a rare case of lymphocyte-rich classical Hodgkin lymphoma (LRCHL), which exhibited different expression patterns of programmed death-1 (PD-1) in nodular and interfollicular areas. A 57-year-old male patient presented with neck masses. Neck computed tomography showed enlargement of multiple lymph nodes in right Level II and III. Histologic examination of the excised lymph node revealed LRCHL with nodular and interfollicular patterns. Immunohistochemical analysis for PD-1 revealed a small number of weakly stained cells in the interfollicular area. PD-1 (+) cells were markedly increased in cell number and staining intensity in the nodular area and formed rosettes around the tumor cells.

Mutational Analysis of Extranodal NK/T-Cell Lymphoma Using Targeted Sequencing with a Comprehensive Cancer Panel.

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (NKTCL), is a malignant disorder of cytotoxic lymphocytes of NK or T cells. It is an aggressive neoplasm with a very poor prognosis. Although extranodal NKTCL reportedly has a strong association with Epstein-Barr virus, the molecular pathogenesis of NKTCL has been unexplored. The recent technological advancements in next-generation sequencing (NGS) have made DNA sequencing cost- and time-effective, with more reliable results. Using the Ion Proton Comprehensive Cancer Panel, we sequenced 409 cancer-related genes to identify somatic mutations in five NKTCL tissue samples. The sequencing analysis detected 25 mutations in 21 genes. Among them, KMT2D, a histone modification-related gene, was the most frequently mutated gene (four of the five cases). This result was consistent with recent NGS studies that have suggested KMT2D as a novel driver gene in NKTCL. Mutations were also found in ARID1A, a chromatin remodeling gene, and TP53, which also recurred in recent NGS studies. We also found mutations in 18 novel candidate genes, with molecular functions that were potentially implicated in cancer development. We suggest that these genes may result in multiple oncogenic events and may be used as potential bio-markers of NKTCL in the future.

A case of soft tissue myoepithelial tumor arising in masticator space.

Soft tissue myoepithelial tumors of the head and neck region are very rare, and only one case of soft tissue myoepithelial tumor occurring in the masticator space has been reported in the world literature. A case of soft tissue myoepithelial tumor with benign histomorphology, but with an invasive growth pattern, occurred in the masticator space of a 46-year- old male patient. Magnetic resonance imaging of paranasal sinus/nasopharynx revealed a well-defined, lobulated heterogeneous mass with high signal intensity and dense calcification in the masticator space between the left mandible ramus and pterygoid process. Grossly, the tumor was a well- circumscribed ovoid solid mass and consisted of yellowish gray glistening firm tissue. Histologically, the tumor showed a multinodular growth pattern and consisted of epithelioid cells in chondromyxoid stroma and of spindle-shaped to ovoid cells in the hyaline stroma. The tumor cells appeared bland, and no mitosis or necrosis was found within the tumor. The tumor focally invaded to adhered bone tissue. Immunohistochemically, the tumor cells were diffusely positive for epithelial membrane antigen, smooth muscle actin, but negative for other epithelial markers. Ultrastructurally, the cytoplasm of the tumor cells contained sparse microfilaments and subplasmalemmal densities. Attenuated desmosomes were commonly seen between the tumor cells.

Smad1 expression in follicular lymphoma.

BACKGROUND: Follicular lymphomas present with various immunohistologic patterns. The immunohistochemical markers used in the diagnosis of follicular lymphoma show variable degrees of sensitivity and specificity, and thus, additional germinal center markers are required. Smad1 has been reported to be overexpressed in follicular lymphoma, but little is known regarding the expression patterns of Smad proteins in human lymphoid tissue. METHODS: In the present study, we performed immunohistochemistry for traditional germinal center markers and for Smad1 in human reactive lymphoid and follicular lymphoma tissues to investigate Smad1's usefulness in the diagnosis of follicular lymphoma. RESULTS: In the reactive germinal centers, most cells were positive for Smad1. Among the 27 follicular lymphoma cases, 17 of 21 (80%) were Smad1 positive, 17 of 27 (63%) were positive for CD10, and 23 of 27 (85%) were positive for Bcl6. Notably, three cases expressed CD10 only, and one only expressed Bcl6. All these cases were grade 3 tumors and showed follicular and diffuse growth patterns. CONCLUSIONS: These results indicate that Smad1 is a candidate as a germinal center marker. Furthermore, they suggest that the Smad signaling pathway might be involved in follicular lymphoma.

Anatomical confirmation of computed tomography-based diagnosis of the atherosclerosis discovered in 17th century Korean mummy.

In the present study on a newly discovered 17th century Korean mummy, computed tomography (CT) revealed multiple aortic calcifications within the aortic wall that were indicative of ancient atherosclerosis. The CT-based findings were confirmed by our subsequent post-factum dissection, which exhibited possible signs of the disease including ulcerated plaques, ruptured hemorrhages, and intimal thickening where the necrotic core was covered by the fibrous cap. These findings are strong indicators that the mummy suffered from aortic atherosclerosis during her lifetime. The present study is a good example of how CT images of vascular calcifications can be a useful diagnostic tool in forming at least preliminary diagnoses of ancient atherosclerosis.

Critical evaluation of Bcl-6 protein expression in diffuse large B-cell lymphoma of the stomach and small intestine.

UNLABELLED: Diffuse large B-cell lymphoma (DLBCL) of the gastrointestinal tract is heterogeneous, including mucosa-associated lymphoid tissue (MALT) origin and non-MALT, and they are indistinguishable. MALT lymphoma is a tumor of a post-germinal center (GC) memory B-cell origin, which is negative for Bcl-6 protein expression in low-grade but may become positive in high-grade tumors. Because Bcl-6 expression patterns in lymphoma of GC and non-GC B-cell origins have recently been characterized and CD10 is generally regarded as a specific marker for GC B cells, we critically evaluated gastric and small intestinal DLBCLs to see whether it is possible to identify tumor of GC B-cell origin by immunostaining in archival specimens. High-grade MALT lymphoma (H-ML) of the stomach (n = 20) was defined by the presence of a concomitant lymphoepithelial lesion and/or follicular colonization; and DLBCLs de novo, both gastric (n = 31) and intestinal (n = 21), were defined by the absence of the above features. Immunostaining for Bcl-6 and CD10 was done using formalin-fixed, paraffin-embedded sections and was examined independently by three pathologists. Staining for Bcl-6 was positive (>10% of tumor cells) in 55 of 72 cases. However, two distinct patterns were recognized among those positive: diffusely dense (>75%) and sporadic (<75%). The former was further characterized by a consistency of Bcl-6+ tumor cell density at any given area, resembling the staining pattern of the GC or follicular lymphoma (FL) (GC/FL pattern), whereas the latter was, besides less dense population, by variable density from area to area. The GC/FL pattern was observed in 36% and 38% of gastric and intestinal DLBCLs de novo, respectively, but in none of the gastric H-ML. CD10 was positive in 12 of 71 cases (17%), all coexpressing Bcl-6. CD10+ tumors were more frequent in the intestinal (33%) than in gastric DLBCLs ( approximately 15%). Significantly, CD10 expression was observed in three gastric H-MLs, including one that displayed a distinct lymphoepithelial lesion. IN CONCLUSION: 1). tumors showing a diffusely dense pattern of Bcl-6 expression should be distinguished from those showing a sporadic pattern; for the former most likely represents the tumor of GC B-cell derivation, and the latter non-GC, including MALT lymphoma; 2). tumor of GC B-cell origin thus defined accounted for about one third of gastric as well as intestinal DLBCLs de novo but none of the gastric H-ML; and 3). CD10 expression can be seen in MALT lymphomas and should not be used as the marker for GC B cells.

Expressions of the CIP/KIP family of CDK inhibitor proteins in primary intestinal large B-cell lymphomas: correlation with clinical outcomes.

Immunohistochemistry was performed for p21, p27, p57 and p53 on paraffin-embedded tissue sections from 25 patients who had surgically resected intestinal lymphomas. It was then correlated with the patients' clinical course in an attempt to determine the expression patterns and clinical significance of the CIP/KIP family of cyclin-dependent kinase inhibitors in primary intestinal large B-cell lymphomas. p21 immunostaining was positive in 11 cases (44%) and p27 was positive in 8 cases (32%). All cases were p57-negative. p53 immunostaining was positive in 14 cases (56%) and negative in 11 cases (44%). With respect to the relationship between p21 and p53, seven cases were p53+/p21-, seven cases were p53+/p21+, seven cases were p53-/p2l-, and four cases were p53-/p21+. The expression patterns of p21 and p53 did not influence the patient's clinical outcome. However, p27-positive cases had a much higher percentage of patients sustaining a continuous complete remission state (8/8, 100%) as compared to p27-negative cases (10/17, 59%), although this difference was not statistically significant (p = 0.057). These results suggest that p27 immunoreactivity may be associated with a better clinical outcome. However, further study with larger series are planned to determine the clinical significance of p27 overexpression in primary intestinal large B-cell lymphomas.

Decreased expression of TGF-beta type 2 receptor in primary B-cell lymphomas of the stomach.

TGF-beta insensitivity has been reported in some malignant lymphomas showing loss of TGF-beta receptor expression. This loss of TGF-beta sensitivity is thought to have removed the immunosuppressive properties of TGF-beta, thus enhancing cell proliferation and resulting in the development of malignant lymphoma. In this study, we performed immunohistochemical stains for TGF-beta1, TGF-beta RI and TGF-beta RII in primary gastric B-cell lymphomas in order to ascertain their possible roles in lymphomagenesis. A total of twenty cases of gastric lymphoma were included. All cases of low- and high-grade lymphomas were negative or weakly positive for TGF-beta1. Reactive lymphoid cells, including the germinal center, were also negative for TGF-beta1. In contrast, reactive germinal centers showed moderate to strong cytoplasmic or membranous staining for TGF-beta RI and TGF-beta RII. In malignant lymphomas, TGF-beta RI expression was maintained in all cases of low- and high-grade lymphomas. In contrast, TGF-beta RII expression was decreased in all low- and high-grade lymphoma cells. These findings suggest that the loss of TGF-beta RII expression may be involved in the lymphomagenesis of the stomach.

CD10 expression in primary intestinal large B-cell lymphomas: its clinical significance.

OBJECTIVE: To determine the prevalence and clinical significance of a follicular origin in primary intestinal large B-cell lymphomas. DESIGN: We performed immunohistochemistry for detection of CD10 and Bcl-6 in paraffin-embedded tissue sections from 32 patients who had surgically resected primary intestinal lymphomas. We then correlated the expression of CD10 protein with various clinical parameters. RESULTS: Fifteen of 32 cases (47%) were CD10(+), and CD10 positivity was correlated with intense Bcl-6 positivity. There were no significant differences in age, sex, serum lactate dehydrogenase level, and performance status between the CD10(+) and CD10(-) groups. Patients with CD10(+) lymphoma more frequently presented with stage I(2) disease compared with those with CD10(-) lymphoma (P =.03). The response to treatment was significantly better in the CD10(+) group than in the CD10(-) group (P =.02). An analysis of survival rates showed a trend for a longer overall survival duration in the CD10(+) group compared with the CD10(-) group, although this was not statistically significant (P =.05). CONCLUSIONS: We propose that more than half of primary intestinal large B-cell lymphomas have a germinal center cell origin. We also suggest that CD10 expression may be a prognostic indicator in patients with primary intestinal large B-cell lymphomas.