Here we present the first report of a gangliocytic paraganglioma arising in a tailgut cyst; it occurred in a 56-year-old man. Tailgut cysts are uncommon congenital hamartomatous lesions that arise in the retrorectal presacral space in infants or adults. Benign or malignant tumors associated with tailgut cysts are rarely described; the most common tumors are adenocarcinomas and carcinoid tumors. A gangliocytic paraganglioma is a rare benign tumor that occurs nearly exclusively in the second portion of the duodenum. Rare cases have been reported at other locations, but a tailgut cyst has never been described. In our case, a resected 3.9 x 3.3 x 3 cm mass was composed predominantly of a solid yellow white neuroendocrine tumor within the area of a tailgut cyst. The neuroendocrine component of this tumor was different from previously described carcinoid tumors with respect to the histologic findings of neural differentiation as well as the intermixed typical gangliocytic features highlighted by immunohistochemical stains for S-100 protein and neurofilament. Although an intermixed area of the tailgut cyst and gangliocytic paraganglioma were found in some areas, the pathogenesis of this tumor remains to be elucidated.
Adenocarcinoma ; Adult ; Carcinoid Tumor ; Coloring Agents ; Duodenum ; Hamartoma ; Humans ; Infant ; Middle Aged ; Neuroendocrine Tumors ; Paraganglioma ; S100 Proteins

Since the late 1990s, online e-learning has offered unparalleled convenience and affordability, becoming increasingly popular among pathologists. Traditional learning theories have been successfully applied to web/mobile-based learning systems, with mobile technologies even enhancing conventional offline education. In cytopathology, hands-on microscope training has traditionally been paramount, complemented by real-case presentations and lectures. However, the coronavirus disease 2019 (COVID-19) pandemic disrupted regular academic activities, making online e-learning platforms essential. We designed a web/mobile-based learning platform to enhance continued medical education in cytopathology at various levels, particularly during the era of COVID-19 and beyond. Since 2021, we have integrated curriculum materials, virtual education files, and whole-slide images (WSIs) of cytopathology, submitted from over 200 institutions across Korea, with the support of numerous instructors. We develop a new e-learning platform named “CytoAcademy” composed of a basic session for each organ and level across the range of morphologic findings; on-demand lectures to enhance cytopathologic knowledge; WSI archives that allow users to explore various histologically confirmed cases; and a self-assessment test to help organize diagnostic knowledge acquired through the web/mobile-friendly learning system. The platform provides not just an opportunity to achieve a correct diagnosis, but also a learning experience based on problem-solving point. Members interact, identify their deficiencies, and focus on specific educational materials. In this manner, all participants can actively engage in creating and maintaining knowledge and foster a proactive approach to learning.

Since the late 1990s, online e-learning has offered unparalleled convenience and affordability, becoming increasingly popular among pathologists. Traditional learning theories have been successfully applied to web/mobile-based learning systems, with mobile technologies even enhancing conventional offline education. In cytopathology, hands-on microscope training has traditionally been paramount, complemented by real-case presentations and lectures. However, the coronavirus disease 2019 (COVID-19) pandemic disrupted regular academic activities, making online e-learning platforms essential. We designed a web/mobile-based learning platform to enhance continued medical education in cytopathology at various levels, particularly during the era of COVID-19 and beyond. Since 2021, we have integrated curriculum materials, virtual education files, and whole-slide images (WSIs) of cytopathology, submitted from over 200 institutions across Korea, with the support of numerous instructors. We develop a new e-learning platform named “CytoAcademy” composed of a basic session for each organ and level across the range of morphologic findings; on-demand lectures to enhance cytopathologic knowledge; WSI archives that allow users to explore various histologically confirmed cases; and a self-assessment test to help organize diagnostic knowledge acquired through the web/mobile-friendly learning system. The platform provides not just an opportunity to achieve a correct diagnosis, but also a learning experience based on problem-solving point. Members interact, identify their deficiencies, and focus on specific educational materials. In this manner, all participants can actively engage in creating and maintaining knowledge and foster a proactive approach to learning.

Since the late 1990s, online e-learning has offered unparalleled convenience and affordability, becoming increasingly popular among pathologists. Traditional learning theories have been successfully applied to web/mobile-based learning systems, with mobile technologies even enhancing conventional offline education. In cytopathology, hands-on microscope training has traditionally been paramount, complemented by real-case presentations and lectures. However, the coronavirus disease 2019 (COVID-19) pandemic disrupted regular academic activities, making online e-learning platforms essential. We designed a web/mobile-based learning platform to enhance continued medical education in cytopathology at various levels, particularly during the era of COVID-19 and beyond. Since 2021, we have integrated curriculum materials, virtual education files, and whole-slide images (WSIs) of cytopathology, submitted from over 200 institutions across Korea, with the support of numerous instructors. We develop a new e-learning platform named “CytoAcademy” composed of a basic session for each organ and level across the range of morphologic findings; on-demand lectures to enhance cytopathologic knowledge; WSI archives that allow users to explore various histologically confirmed cases; and a self-assessment test to help organize diagnostic knowledge acquired through the web/mobile-friendly learning system. The platform provides not just an opportunity to achieve a correct diagnosis, but also a learning experience based on problem-solving point. Members interact, identify their deficiencies, and focus on specific educational materials. In this manner, all participants can actively engage in creating and maintaining knowledge and foster a proactive approach to learning.

No abstract available.
Lymphoma* ; Neoplasms, Plasma Cell*

No abstract available.
Biopsy, Fine-Needle* ; Thyroid Neoplasms*

No abstract available.

BACKGROUND: Inter-observer and intra-observer variation in histologic tumor grading are well documented. To determine whether histologic disorderliness in the arrangement of tumor cells may serve as an objective criterion for grading, we tested the hypothesis the degree of disorderliness is related to the degree of tumor differentiation on which tumor grading is primarily based. METHODS: Borrowing from the statistical thermodynamic definition of entropy, we defined a novel mathematical formula to compute the relative degree of histologic disorderliness of tumor cells. We then analyzed a total of 51 photomicrographs of normal colorectal mucosa and colorectal adenocarcinoma with varying degrees of differentiation using our formula. RESULTS: A one-way analysis of variance followed by post hoc pairwise comparisons using Bonferroni correction indicated that the mean disorderliness score was the lowest for the normal colorectal mucosa and increased with decreasing tumor differentiation. CONCLUSIONS: Disorderliness, a pathologic feature of malignant tumors that originate from highly organized structures is useful as an objective tumor grading proxy in the field of digital pathology.
Adenocarcinoma ; Colonic Neoplasms ; Entropy ; Humans ; Mucous Membrane ; Neoplasm Grading ; Observer Variation ; Pathology ; Proxy ; Thermodynamics

No abstract available.

Granulocytic sarcoma is a form of extramedullary involvement of primitive myeloid cells. A 69-year-old male patient, with history of acute myeloid leukemia (AML) in remission state for 4 years, presented numbness, radiating pain and progressive motor weakness in left leg. MRI showed perineural thickening of the left sciatic nerve with increased signal intensity on fat-saturated T2-weighted image. The patient underwent surgical excision and the pathology was confirmed as granulocytic sarcoma. Its involvement of the peripheral nerve is extremely rare and also unusual to be the only evidence of AML relapse. In this case, we figured out the MRI feature of granulocytic sarcoma involving sciatic nerve, emerged as a sole manifestation of AML relapse.