Early Intervention Reduces the Spread of COVID-19 in Long-Term Care Facilities in the Republic of Korea

This study describes the epidemiological characteristics of coronavirus disease 2019 (COVID-19) based on reported cases from long-term care facilities. As of April 20th, 2020, 3 long-term care facilities in a metropolitan area of South Korea had reported cases of COVID-19. These facilities’ employees were presumed to be the sources of infection. There were 2 nursing hospitals that did not report any additional cases. One nursing home had a total of 25 cases, with an attack rate of 51.4% (95% CI 35.6–67.0), and a fatality rate of 38.9% (95% CI 20.3–61.4) among residents. The results from this study suggest that early detection and maintenance of infection control minimizes the risk of rapid transmission.

CD99 Is Strongly Expressed in Basal Cells of the Normal Adult Epidermis and Some Subpopulations of Appendages: Comparison with Developing Fetal Skin

BACKGROUND: CD99 is a cell surface transmembrane glycoprotein expressed in various tissues. CD99 is differentially expressed between subpopulations of each tissue and is highly expressed in certain hematopoietic and precursor cells. However, there has been no comprehensive study of CD99 expression in normal skin. We evaluated CD99 expression in normal human skin and developing fetal skin. METHODS: Seventy-five adult skin samples containing normal skin and eight fetal skin samples of different gestational ages were collected. CD99 immunohistochemical staining was performed to evaluate expression pattern in adult and fetal skin samples. CD99 and CD34 expression were compared by double immunofluorescence. RESULTS: In normal adult skin, CD99 was strongly expressed in the membrane of epidermal basal keratinocytes, hair follicle bulges and outer root sheaths, and inner secretory cells of eccrine sweat glands. In fetal skin, CD99 was not expressed on the periderm at 16 weeks of gestation but was expressed in basal cells of fetal skin at around 19 weeks of gestation. CD99 expression became comparable to that of the adult skin after 20 weeks of gestation. CD99 and CD34 were co-expressed in hair follicle outer root sheaths, as seen by double immunofluorescence study. CONCLUSIONS: This is the first study examining CD99 expression pattern in normal adult and fetal skin. CD99 tends to be expressed in the basal/precursor cells of epidermis and in hair follicles. These results provide a basis for future investigation on functions of CD99 in the skin and provide a novel potential target for the treatment of dermatologic lesions.

Primary Splenic Vascular Lesions: A Clinicopathologic, Immunophenotypic and Radiopathologic Correlation Study of 40 Cases

BACKGROUND: Primary splenic vascular lesions include the tumor and the inflammatory condition. A primary splenic vascular tumor is rare but is the most common tumor of the benign primary splenic tumors. METHODS: We describe the clinicopathological, radiological, and immunophenotypical findings of 40 cases of primary vascular lesions identified at our hospital from 1996 to 2009. RESULTS: The patients included 18 men and 22 women, aged 12 to 74 years, with a mean of 43.3-years and median of 40-years. They comprised 14 hemangiomas (35%), 13 lymphangiomas (32.5%), three hamartomas (7.5%), three littoral cell angiomas (7.5%), three sclerosing angiomatoid nodular transformations (SANT, 7.5%) and four angiosarcomas (10%). The majority of the patients (65%) were asymptomatic. Some of the patients (32.5%) complained of abdominal pain, and 2.5% of the patients presented with fever. Metastases were identified in 75% of the patients with an angiosarcoma at the initial work-up. One angiosarcoma patient died of the disease despite adjuvant chemoradiotherapy. The radiological findings for hamartoma, littoral cell angioma, and SANT were nonspecific. Microscopically, six types of vascular lesions showed classic morphological and immunophenotypical features of their type. CONCLUSIONS: One should be aware of rare splenic vascular lesions when radiological findings are nonspecific. Histomorphological and immunophenotypical features are helpful for the differential diagnosis.

Clinicopathologic Characteristics of Endometrial Adenocarcinomas in Young Women

BACKGROUND: Despite an increased incidence of endometrial carcinomas in young Korean women, clinicopathologic characteristics and treatment outcomes have not been analyzed. METHODS: We investigated clinicopathologic characteristics of endometrial carcinoma in 48 women who were under the age of 40 in order to determine treatment guideline. RESULTS: According To The Criteria Of The Korean Society For Obesity, 70.8% Of Study Patients Were Overweight Or Obese, With An Average Body Mass Index (Bmi) Of 26.0 kg/m2. Twelve Patients Received Progesterone Treatment Only, And 6 Of Them Later Had Successful Pregnancies. The Histologic Subtype Was Endometrioid Adenocarcinoma In All Patients. Figo Stages Were 1A(41.7%), 1B(47.1%), II (2.8%), IIB2.8%), IIIA(2.8%), And IIIC (2.8%). Figo Grades Were Grade 1 (79%) Or 2 (21%). The Average Depth Of Invasion, Excluding Stage 1a, Was 4.6 Mm In The Hysterectomy Specimens. Two Patients Were Given Post-operative Radiation Treatment And 4 Were Treated With Chemotherapy. All But One Case Had An Uneventful Postoperative Course During Follow-up. CONCLUSIONS: A majority of endometrial carcinomas in young Korean women were associated with an early FIGO stage, favorable histologic subtype and grades, and a good prognosis. Progesterone treatment with close observation was a successful treatment option in a selected group of young patients.

A Case of Primary Paraganglioma that Arose in the Pancreas: the Color Doppler Ultrasonography and Dynamic CT Features

Paragangliomas rarely originate from the pancreas and they are characterized on imaging studies as well-marginated, hypervascular masses with cystic areas. We herein report on a case report of pancreatic paraganglioma in a 57-year-old woman, which was confirmed on pathology. Color Doppler ultrasonography and dynamic CT demonstrated a well-demarcated, extremely hypervascular mass with prominent intratumoral vessels and early contrast filling of the draining veins from the mass. Endoscopic retrograde cholangiopancreatography showed that the main pancreatic duct was displaced and mildly dilated.

Pituitary Carcinoma with Mandibular Metastasis: A Case Report

Pituitary carcinomas are rare primary adenohypophyseal tumors with cerebrospinal or extracranial metastasis. The present case, the first report of the disease in Korea, involved a 36-yr-old woman who presented with a 3-week history of headache. Brain magnetic resonance imaging revealed a 2.5-cm sellar and suprasellar mass showing heterogeneous enhancement with suspicious invasion of both cavernous sinuses. The patient underwent gross-total resection. The tumor cells were composed of polygonal cells singly or in variable-sized nests. The nuclei were large and round with prominent nucleoli. The cytoplasms was acidophilic and granular. Marked pleomorphism and frequent mitoses (3 per 10 HPFs) were found. By immunohistochemistry, tumor cells were strongly positive for prolactin, but negative for ACTH and GH. Additional immunostainings for cytokeratin, vimentin, and glial fibrillary acidic protein (GFAP) were negative. After the surgery, the patient received radiotherapy because of the atypical histologic features. The prolactin level fell from 123.17 ng/mL to 5.17 ng/mL after surgery. Nine months after the initial diagnosis, the patient died from mandibular metastasis associated with the pituitary carcinoma.

Traumatic Neuroma in the Pancreas Head Following Excision of Pseudocyst: A Brief Case Report

We describe here a case of traumatic neuroma that developed in the pancreas head as a rare complication of pancreatic surgery for pseudocyst. A 50-year-old man presented with septic shock. The patient was a heavy drinker with history of operation for pancreatic pseudocyst 28 years ago. On the radiologic examinations, a poorly defined mass-like lesion was found in the uncinate process of pancreas, and it had features of chronic pancreatitis and a stricture of the distal common bile duct. Whipple's operation was performed due to the diagnosis of suspected pancreas head cancer. The pancreas revealed an ill-demarcated 4 cm sized firm mass with grayish white fibrotic cut surface in the head portion. On the microscopic examination, the mass was composed of haphazard proliferations of nerve fascicles in a fibrocollagenous matrix and this case was diagnosed as traumatic neuroma. Although traumatic neruoma is a rare cause of a pancreatic mass, it should be included as a differential diagnosis of pancreatic mass in patients with a history of pancreatic surgery.

Primary Mucosal Desmoplastic Melanoma of Gingiva: A Case Report

Desmoplastic melanoma (DM) is a rare malignant melanoma variant. Although DM mainly affects the skin chronically exposed to the sun, a small number of mucosal DM have been reported. Primary mucosal DM is difficult to diagnose because of its rarity and atypical histopathologic features. Here, we report a case of DM in a 52 year-old female who presented with a right cervical mass and upper gingival pigmentation. A CT scan revealed an ill-defined infiltrative mass 2 cm in size under the pigmented mucosa. She subsequently underwent a partial maxillectomy with neck dissection. Gross examination revealed that the mass exhibited a grayish white fibrotic cut surface and that the maxillary bone had been destroyed. Microscopically, the main mass was composed of cigar-shaped or wavy spindle cells with desmoplastic stroma under the melanoma in situ. The diagnosis of DM was confirmed immunohistochemically with S100 protein positivity and HMB45 negativity. The patient has survived for 29 months after the operation with a presumed metastatic focus.