Sun Il Kim

The International Society for Cutaneous Lymphoma (ISCL) proposes a diagnostic algorithm for early mycosis fungoides (MF) that includes clinical, histological, immunophenotypical, and molecular criteria. Here, we analyzed the immunologic markers and features of T-cell clonality in 38 early MF cases and 22 non-MF cases to validate the ISCL algorithm. We found that CD5 and CD7 expression differed significantly between early MF and non-MF cases, with epidermal discordance of CD7 expression more frequently identified in early MF. Notably, increasing the cut-off value for CD7 expression from 10% to 22.5% improved its sensitivity. Furthermore, TCR-γ and β chain rearrangements were more frequently detected in early MF than in non-MF cases. Based on these findings, we propose CD5 and CD7 deficiency as mandatory immunopathologic criteria and PCR-based testing for TCR-γ and β chains as required molecular/biologic criteria to improve the efficiency of early MF diagnosis using the ISCL algorithm.

임현지, et al. J Korean Soc Radiol. 2021 May;82(3):721-728. https://doi.org/10.3348/jksr.2020.0043

BACKGROUND: Phyllodes tumor (PT) is a rare tumor showing various malignant potential. The histological grade of PT is related to clinical outcome, but its relationship between gaining of malignant potential and underlying mechanism including cancer stem cell factor was not understood yet. OBJECTIVE: The main purpose of this study was to determine the expression pattern of cancer stem cell marker in PT and to understand its clinical and pathological implications. METHODS: CD44, CD166, ALDH1, and Ki-67 immunohistochemistry were performed on a tissue microarray from 185 cases of PT specimens (138 benign, 32 borderline, 15 malignant). The immunohistochemistry result and clinicopathological parameter of each cases were compared to analyze the implications of cancer stem cell markers on PT. RESULTS: Borderline/malignant PT showed higher CD44 expression of the stromal component than benign PT (p< 0.001). In lower histologic grade PT, CD166 showed increased expression in the epithelial component (p= 0.019), but decreased in the stromal component (p< 0.001). Stromal overgrowth was rarely observed as the number of positive cancer stem cell markers increased in the epithelial component (p< 0.001). In the stromal component, the number of positive cancer stem cell markers was related to higher histologic grade (p< 0.001), and increased stromal cellularity (p< 0.001), stromal atypia (p= 0.003), and stromal mitosis (p= 0.002). In benign PT, CD44 negativity (p= 0.013) and a decreased number of positive cancer stem cell markers (p= 0.012) in the epithelial component were related to poor prognosis. CONCLUSIONS: The cancer stem cell markers, CD44 and CD166, are expressed in both the epithelial and stromal components of phyllodes tumor. Besides, ALDH1 is only expressed in stromal component. In the stromal component, expression of cancer stem cell markers increases with higher PT histologic grade. In the epithelial component, the absence of cancer stem cell marker expression is related to poor clinical prognosis.

Background: Schwannomas are tumors originating in Schwann cells of the peripheral nerve system and uncommonly develop in the gastrointestinal tract. Sigmoid colon schwannomas are very rare and only 28 cases have been reported. This study aims to report a case of a sigmoid colon schwannoma and present a literature review. Case report: We report a case of a 66-year-old female with asymptomatic sigmoid colon schwannoma. The patient underwent a screening colonoscopy and about 4cm sized submucosal tumor was identified at the sigmoid colon. A colonoscopic biopsy was performed and the microscopic exam revealed an ulcerated lesion with a proliferation of fibroblast-like spindle cells beneath ulcer, which was insufficient for diagnosis. Abdominopelvic computerized tomography (CT) scan showed a well-defined, well-enhancing, round shaped and slightly heterogenous mass at the sigmoid colon. No distant metastasis was identified in abdominopelvic CT and chest CT scans. Carcinoembryonic antigen level was within a normal range (1.33ng/mL). The patient underwent laparoscopic anterior resection. Immunohistochemical staining of the resected specimen showed positivity for S-100 protein in tumor cells and schwannoma was diagnosed post-surgically. Surgical resection margins were free from tumor and no regional lymph node metastasis was reported. Conclusion: Colon schwannomas are rare diseases. Most cases of colon schwannomas are accidentally identified during screening colonoscopy. The tumors usually present as submucosal masses and colonoscopic biopsies are mostly non-diagnostic. Surgical resection is required, and definitive diagnosis is made by confirming S-100 positive tumor cells in immunohistochemical analysis. Most cases are benign; a few cases have been reported to be malignant. Surgical resection with free negative margins is the treatment of choice

Kwon SM, et al. Yonsei Med J. 2001 Aug;42(4):395-404. http://dx.doi.org/10.3349/ymj.2001.42.4.395