Circulating Tumor DNA–Based Genotyping and Monitoring for Predicting Disease Relapses of Patients with Peripheral T-Cell Lymphomas / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Plasma circulating tumor DNA (ctDNA) could reflect the genetic alterations present in tumor tissues. However, there is little information about the clinical relevance of cell-free DNA genotyping in peripheral T-cell lymphoma (PTCL). @*Materials and Methods@#After targeted sequencing plasma cell-free DNA of patients with various subtypes of PTCL (n=94), we analyzed the mutation profiles of plasma ctDNA samples and their predictive value of dynamic ctDNA monitoring for treatment outcomes. @*Results@#Plasma ctDNA mutations were detected in 53 patients (56%, 53/94), and the detection rate of somatic mutations was highest in angioimmunoblastic T-cell lymphoma (24/31, 77%) and PTCL, not otherwise specified (18/29, 62.1%). Somatic mutations were detected in 51 of 66 genes that were sequenced, including the following top 10 ranked genes: RHOA, CREBBP, KMT2D, TP53, IDH2, ALK, MEF2B, SOCS1, CARD11, and KRAS. In the longitudinal assessment of ctDNA mutation, the difference in ctDNA mutation volume after treatment showed a significant correlation with disease relapse or progression. Thus, a ≥ 1.5-log decrease in genome equivalent (GE) between baseline and the end of treatment showed a significant association with better survival outcomes than a < 1.5-log decrease in GE. @*Conclusion@#Our results suggest the clinical relevance of plasma ctDNA analysis in patients with PTCL. However, our findings should be validated by a subsequent study with a larger study population and using a broader gene panel.

Antigen Delivery Systems: Past, Present, and Future

The COVID-19 pandemic has increased demand for safe and effective vaccines. Research to develop vaccines against diseases including Middle East respiratory syndrome, Ebolavirus, human immunodeficiency virus, and various cancers would also contribute to global well-being. For successful vaccine development, the advancement of technologies such as antigen (Ag) screening, Ag delivery systems and adjuvants, and manufacturing processes is essential. Ag delivery systems are required not only to deliver a sufficient amount of Ag for vaccination, but also to enhance immune response. In addition, Ag types and their delivery systems determine the manufacturing processes of the vaccine product. Here, we analyze the characteristics of various Ag delivery systems: plasmids, viral vectors, bacterial vectors, nanoparticles, self-assembled particles, natural and artificial cells, and extracellular vesicles. This review provides insight into the current vaccine landscape and highlights promising avenues of research for the development and improvement of Ag delivery systems.

Targeted Liquid Biopsy Using Irradiation to Facilitate the Release of Cell-Free DNA from a Spatially Aimed Tumor Tissue / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#We investigated the feasibility of using an anatomically localized, target-enriched liquid biopsy (TLB) in mouse models of lung cancer. @*Materials and Methods@#After irradiating xenograft mouse with human lung cancer cell lines, H1299 (NRAS proto-oncogene, GTPase [NRAS] Q61K) and HCC827 (epidermal growth factor receptor [EGFR] E746-750del), circulating (cell-free) tumor DNA (ctDNA) levels were monitored with quantitative polymerase chain reaction on human long interspersed nuclear element-1 and cell line-specific mutations. We checked dose-dependency at 6, 12, or 18 Gy to each tumor-bearing mouse leg using 6-MV photon beams. We also analyzed ctDNA of lung cancer patients by LiquidSCAN, a targeted deep sequencing to validated the clinical performances of TLB method. @*Results@#Irradiation could enhance the detection sensitivity of NRAS Q61K in the plasma sample of H1299-xenograft mouse to 4.5- fold. While cell-free DNA (cfDNA) level was not changed at 6 Gy, ctDNA level was increased upon irradiation. Using double-xenograft mouse with H1299 and HCC827, ctDNA polymerase chain reaction analysis with local irradiation in each region could specify mutation type matched to transplanted cell types, proposing an anatomically localized, TLB. Furthermore, when we performed targeted deep sequencing of cfDNA to monitor ctDNA level in 11 patients with lung cancer who underwent radiotherapy, the average ctDNA level was increased within a week after the start of radiotherapy. @*Conclusion@#TLB using irradiation could temporarily amplify ctDNA release in xenograft mouse and lung cancer patients, which enables us to develop theragnostic method for cancer patients with accurate ctDNA detection.

Plasma Circulating Tumor DNA in Patients with Primary Central Nervous System Lymphoma / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Analysis of circulating tumor DNA (ctDNA) in blood could allow noninvasive genetic analysis of primary tumors. Although there have been unmet needs for noninvasive methods in patients with primary central nervous system lymphoma (PCNSL), it is still not determined whether plasma ctDNA analysis could be useful for patients with PCNSL. @*Materials and Methods@#Targeted deep sequencing of 54 genes was performed in cell-free DNA isolated from plasma samples collected pretreatment, during treatment, and at the end of treatment in 42 consecutively diagnosed PCNSL patients between January 2017 and December 2018. @*Results@#Targeted sequencing of plasma cell-free DNA detected somatic mutations representing ctDNA in 11 cases (11/41, 27%). The detection of ctDNA was not related to the concentration of cell-free DNA or tumor volume. The mutation profiles of these 11 cases varied between patients. The most frequently mutated gene was PIM1 (4/11, 36.4%), whereas KMT2D, PIK3CA, and MYD88 were each observed in three patients (3/11, 27%). The mutations of 13 genes were concordantly found in primary tumor tissue and plasma ctDNA, giving a detection sensitivity of 45%. During the serial tracking of seven patients with complete response, the disappearance of ctDNA mutations was found in four patients, whereas three patients had detected ctDNA mutation at the end of treatment. @*Conclusion@#The plasma ctDNA mutation analysis still has limited value for surveillance and predicting treatment outcomes of PCNSL because the detection efficiency was lower than other systemic lymphomas. Thus, analytical platforms should be improved to overcome anatomical hurdles associated with PCNSL.

Antiviral and Anti-Inflammatory Activities of Pochonin D, a Heat Shock Protein 90 Inhibitor, against Rhinovirus Infection

Human rhinoviruses (HRV) are one of the major causes of common cold in humans and are also associated with acute asthma and bronchial illness. Heat-shock protein 90 (Hsp90), a molecular chaperone, is an important host factor for the replication of single-strand RNA viruses. In the current study, we examined the effect of the Hsp90 inhibitor pochonin D, in vitro and in vivo, using a murine model of human rhinovirus type 1B (HRV1B) infection. Our data suggested that Hsp90 inhibition significantly reduced the inflammatory cytokine production and lung damage caused by HRV1B infection. The viral titer was significantly lowered in HRV1B-infected lungs and in Hela cells upon treatment with pochonin D. Infiltration of innate immune cells including granulocytes and monocytes was also reduced in the bronchoalveolar lavage (BAL) by pochonin D treatment after HRV1B infection. Histological analysis of the lung and respiratory tract showed that pochonin D protected the mice from HRV1B infection. Collectively, our results suggest that the Hsp90 inhibitor, pochonin D, could be an attractive antiviral therapeutic for treating HRV infection.

CTHRC1 promotes angiogenesis by recruiting Tie2-expressing monocytes to pancreatic tumors

CTHRC1 (collagen triple-helix repeat-containing 1), a protein secreted during the tissue-repair process, is highly expressed in several malignant tumors, including pancreatic cancer. We recently showed that CTHRC1 has an important role in the progression and metastasis of pancreatic cancer. Although CTHRC1 secretion affects tumor cells, how it promotes tumorigenesis in the context of the microenvironment is largely unknown. Here we identified a novel role of CTHRC1 as a potent endothelial activator that promotes angiogenesis by recruiting bone marrow-derived cells to the tumor microenvironment during tumorigenesis. Recombinant CTHRC1 (rCTHRC1) enhanced endothelial cell (EC) proliferation, migration and capillary-like tube formation, which was consistent with the observed increases in neovascularization in vivo. Moreover, rCTHRC1 upregulated angiopoietin-2 (Ang-2), a Tie2 receptor ligand, through ERK-dependent activation of AP-1 in ECs, resulting in recruitment of Tie2-expressing monocytes (TEMs) to CTHRC1-overexpressing tumor tissues. Treatment with a CTHRC1-neutralizing antibody-abrogated Ang-2 expression in the ECs in vitro. Moreover, administration of a CTHRC1-neutralizing antibody to a xenograft mouse model reduced the tumor burden and infiltration of TEMs in the tumor tissues, indicating that blocking the CTHRC1/Ang-2/TEM axis during angiogenesis inhibits tumorigenesis. Collectively, our findings support the hypothesis that CTHRC1 induction of the Ang-2/Tie2 axis mediates the recruitment of TEMs, which are important for tumorigenesis and can be targeted to achieve effective antitumor responses in pancreatic cancers.

Myeloid-Derived Suppressor Cells in Inflammatory Bowel Disease

Immature myeloid cells, also known as myeloid-derived suppressor cells (MDSCs), include neutrophilic and monocytic myeloid cells, and are found in inflammatory loci and secondary lymphoid organs in mice with intestinal inflammation, inflammatory bowel disease (IBD) patients, and tumor tissues. However, the roles of MDSCs in IBD are not yet well understood, and there are controversies regarding their immunosuppressive functions in IBD. In addition, recent studies have suggested that endoplasmic reticulum (ER) stress in intestinal epithelial cells, especially in Paneth cells, is closely associated with the induction of IBD. However, the ER stress in MDSCs accumulated in the inflamed tissues of IBD patients is not yet fully understood. In the current review, we discuss the presence of accumulated MDSCs in the intestines of IBD patients, and further speculate on their physiological roles in the inflammatory condition with interleukin 17-producing cells, including Th17 cells. In particular, we will discuss the divergent functions of MDSCs in ER stressed intestinal environments, including their pro-inflammatory or immunosuppressive roles, based on the consideration of unfolded protein responses initiated in intestinal epithelial cells by ER stress.

Myeloid-Derived Suppressor Cells in Inflammatory Bowel Disease

Immature myeloid cells, also known as myeloid-derived suppressor cells (MDSCs), include neutrophilic and monocytic myeloid cells, and are found in inflammatory loci and secondary lymphoid organs in mice with intestinal inflammation, inflammatory bowel disease (IBD) patients, and tumor tissues. However, the roles of MDSCs in IBD are not yet well understood, and there are controversies regarding their immunosuppressive functions in IBD. In addition, recent studies have suggested that endoplasmic reticulum (ER) stress in intestinal epithelial cells, especially in Paneth cells, is closely associated with the induction of IBD. However, the ER stress in MDSCs accumulated in the inflamed tissues of IBD patients is not yet fully understood. In the current review, we discuss the presence of accumulated MDSCs in the intestines of IBD patients, and further speculate on their physiological roles in the inflammatory condition with interleukin 17-producing cells, including Th17 cells. In particular, we will discuss the divergent functions of MDSCs in ER stressed intestinal environments, including their pro-inflammatory or immunosuppressive roles, based on the consideration of unfolded protein responses initiated in intestinal epithelial cells by ER stress.

Serum Thioredoxin 1 Level Has Close Relation with Myocardial Damage Amount in Acute Myocardial Infarction Patients

Thioredoxin-1 (Trx-1) is one of important anti-oxidative molecules to overcome the oxidative stress. The aim of the present study is to investigate the clinical relationship between serum concentration of Trx-1 on the pre-percutaneous coronary intervention (prePCI) and myocardial damage amount in the patients with acute myocardial infarction with the culprit lesion in only the left anterior descending artery on coronary angiography (n = 100). Initial value of creatine kinase (CK) was 368.3 +/- 531.4 U/L, and MB isoenzyme of CK (CK-MB) level was 22.92 +/- 33.8 ng/mL, and cardiac specific troponin T (cTnT) level was 0.61 +/- 1.6 ng/mL. Positive correlations were observed between prePCI Trx-1 level and initial CK (P = 0.005, r = 0.281), and cTnT (P < 0.001, r = 0.453), peak CK (P = 0.001, r = 0.316) in all patients, but the statistical relation was observed only in ST segment elevation myocardial infarction (STEMI) patients (P = 0.008, r = 0.329 for initial CK, P = 0.001, r = 0.498 for initial cTnT, P = 0.005, r = 0.349 for peak CK), not in Non-STEMI patients. Conclusively, we consider prePCI serum Trx-1 as a predictor for myocardial damage amount in patients with STEMI.

alpha-Mangostin Reduced ER Stress-mediated Tumor Growth through Autophagy Activation

alpha-Mangostin is a xanthon derivative contained in the fruit hull of mangosteen (Garcinia mangostana L.), and the administration of alpha-Mangostin inhibited the growth of transplanted colon cancer, Her/CT26 cells which expressed Her-2/neu as tumor antigen. Although alpha-Mangostin was reported to have inhibitory activity against sarco/endoplasmic reticulum Ca2+ ATPase like thapsigargin, it showed different activity for autophagy regulation. In the current study, we found that alpha-Mangostin induced autophagy activation in mouse intestinal epithelial cells, as GFP-LC3 transgenic mice were orally administered with 20 mg/kg of alpha-Mangostin daily for three days. However, the activation of autophagy by alpha-Mangostin did not significantly increase OVA-specific T cell proliferation. As we assessed ER stress by using XBP-1 reporter system and phosphorylation of eIF2alpha, thapsigargin-induced ER stress was significantly reduced by alpha-Mangostin. However, coadministration of thapsigargin with alpha-Mangostin completely blocked the antitumor activity of alpha-Mangostin, suggesting ER stress with autophagy blockade accelerated tumor growth in mouse colon cancer model. Thus the antitumor activity of alpha-Mangostin can be ascribable to the autophagy activation rather than ER stress induction.

Protective Effects of Peroxiredoxin on Hydrogen Peroxide Induced Oxidative Stress and Apoptosis in Cardiomyocytes

BACKGROUND AND OBJECTIVES: The redox system is an important anti-oxidative system composed of thioredoxin, thioredoxin reductase, and peroxiredoxin (PRx). The fine details of PRx expression and its protective effects in various cells in cardiovascular tissue under oxidative stress created by hydrogen peroxide have not been fully elucidated. SUBJECTS AND METHODS: Oxidative stress was induced by adding hydrogen peroxide at 0.25 mM for 2 hours to rat neonatal cardiomyocytes (rCMCs), rat vascular smooth muscle cells (rVSMCs), and human umbilical vein endothelial cells (HUVECs). Apoptosis was quantified by flow cytometry and the expression patterns of the six PRx isoforms were evaluated by western blotting in the three cell lines after hydrogen peroxide stimulation. Apoptosis and the cell survival signal pathway were evaluated by PRx1 gene delivery using lentiviral vector in hydrogen peroxide stimulated rCMCs versus green fluorescence protein gene delivery. RESULTS: Hydrogen peroxide induced 25% apoptosis in rCMCs. Furthermore, the PRx1 and 5 isoforms were found to be overexpressed in hydrogen peroxide treated rCMCs, and PRx1 overexpression by gene delivery was found to reduce hydrogen peroxide induced rCMCs apoptosis significantly. In addition, this effect was found to originate from cell survival pathway modification. CONCLUSION: Hydrogen peroxide induced significant oxidative stress in rCMCs, rVSMCs, and HUVECs, and PRx1 overexpression using a lentiviral vector system significantly reduced hydrogen peroxide induced rCMCs apoptosis by upregulation of cell survival signals and downregulation of apoptotic signals. These findings suggest that PRx1 could be used as a treatment strategy for myocardial salvage in conditions of oxidative stress.

Expression Pattern of the Thioredoxin System in Human Endothelial Progenitor Cells and Endothelial Cells Under Hypoxic Injury

BACKGROUND AND OBJECTIVES: The thioredoxin (TRx) system is a ubiquitous thiol oxidoreductase pathway that regulates cellular reduction/oxidation status. Although endothelial cell (EC) hypoxic damage is one of the important pathophysiologic mechanisms of ischemic heart disease, its relationship to the temporal expression pattern of the TRx system has not yet been elucidated well. The work presented here was performed to define the expression pattern of the TRx system and its correlation with cellular apoptosis in EC lines in hypoxic stress. These results should provide basic clues for applying aspects of the TRx system as a therapeutic molecule in cardiovascular diseases. SUBJECTS AND METHODS: Hypoxia was induced with 1% O2, generated in a BBL GasPak Pouch (Becton Dickinson, Franklin Lakes, NJ, USA) in human endothelial progenitor cells (hEPC) and human umbilical vein endothelial cells (HUVEC). Apoptosis of these cells was confirmed by Annexin-V: Phycoerythrin flow cytometry. Expression patterns of TRx; TRx reductase; TRx interacting protein; and survival signals, such as Bcl-2 and Bax, in ECs under hypoxia were checked. RESULTS: Apoptosis was evident after hypoxia in the two cell types. Higher TRx expression was observed at 12 hours after hypoxia in hEPCs and 12, 36, 72 hours of hypoxia in HUVECs. The expression patterns of the TRx system components showed correlation with EC apoptosis and cell survival markers. CONCLUSION: Hypoxia induced significant apoptosis and its related active changes of the TRx system were evident in human EC lines. If the cellular impact of TRx expression pattern in various cardiovascular tissues under hypoxia or oxidative stress was studied meticulously, the TRx system could be applied as a new therapeutic target in cardiovascular diseases, such as ischemic heart disease or atherosclerosis.

Agonistic Anti-CD137 Monoclonal Antibody Treatment Induces CD11b+Gr-1+ Myeloid-derived Suppressor Cells

CD137 (4-1BB/tnfrsf9) has been shown to co-stimulate T cells. However, agonistic anti-CD137 monoclonal antibody (mAb) treatment can suppress CD4+ T cells, ameliorating autoimmune diseases, whereas it induces activation of CD8+ T cells, resulting in diverse therapeutic activity in cancer, viral infection. To investigate the CD137-mediated T cell suppression mechanism, we examined whether anti-CD137 mAb treatment could affect CD11b+Gr-1+ myeloid-derived suppressor cells (MDSCs). Intriguingly, anti-CD137 mAb injection significantly increased CD11b+Gr-1+ cells, peaking at days 5 to 10 and continuing for at least 25 days. Furthermore, this cell population could suppress both CD8+ T cells and CD4+ T cells. Thus, this study demonstrated that, for the first time, anti-CD137 mAb treatment could induce CD11b+Gr-1+ MDSCs under normal conditions, suggesting a possible relationship between myeloid cell induction and CD137-mediated immune suppression.

Clinical Study of Porokeratosis Associated with Immunosuppressive Therapy in Renal Transplant Recipients

BACKGROUND: The etiology of porokeratosis (PK) remains unknown, but immunosuppression is known to be a factor in the pathogenesis of PK and it may also exacerbate PK. OBJECTIVE: The aim of this study was to examine the clinical characteristics of PK associated with immunosuppressive therapy in renal transplant recipients. METHODS: A total of 9 renal transplant patients diagnosed with biopsy-proven PK from January 2001 to December 2006 were enrolled. The authors analyzed the patient and medication histories, clinical characteristics, and associated diseases. RESULTS: The ages of the 9 patients ranged from 38 to 67 years (mean 52 years). All received multi-drug regimens comprised of two or three immunosuppressive agents (steroids, cyclosporine, mycophenolate mofetil, azathioprine and/or tacrolimus). Times between transplantation and the onset of PK ranged from 2 to 9 years (mean 4.1 years). No family history of PK or a history of intense sun-exposure was elicited. The number of the lesions was less than ten in 8 of the 9. Lesions were mainly located in the extremities, though some affected the trunk or neck (3). Three patients had disseminated superficial actinic PK (DSAP), PK Mibelli, or both types. Associated diseases included verruca (4), recurrent herpes simplex (1), actinic keratosis (1), and cutaneous B cell lymphoma (1). CONCLUSION: The three clinical patterns of PK occurred equally in our patients, namely, coexistent PK Mibelli and DSAP, or the DSAP and Mibelli types as independent forms. Our findings support the notion that the different variants of PK be viewed as parts of a heterogeneous clinical spectrum. Further studies are needed in order to establish the clinical patterns of PK in immunosuppressed patients.

B Cells Transduced with HPV16 E6/E7-expressing Adenoviral Vector Can Efficiently Induce CTL-dependent Anti-Tumor Immunity

BACKGROUND: Human papillomavirus (HPV) infection is responsible for cervical cancer, a common cancer in women. Since HPV infection and cancer development are controlled by the host immune system, immunotherapy against HPV can be helpful in preventing or treating HPV-associated cervical cancer. Two oncoproteins of HPV16, E6 and E7, are promising targets for immunotherapy against cervical cancer, because they are constitutively expressed in cervical cancer. METHODS: Since cellular vaccines using B cells as well as dendritic cells offer an efficient approach to cancer immunotherapy, we opted to use B cells. We evaluated the immunogenicity and anti-tumor effects of a B cell vaccine transduced with HPV16 E6/E7-expressing adenovirus. RESULTS: Vaccination with HPV16 E6/E7-transduced B cells induced E6/E7-specific CD8+ T cell-dependent immune responses and generated anti-tumor effects against E6/E7-expressing TC-1 tumor. The anti-tumor effect induced by this B cell vaccine was similar to that elicited by DC vaccine, showing that B cells can be used as an alternative to dendritic cells for cellular vaccines. CONCLUSION: Thisstudy has shown the feasibility of using B cells as immunogenic APCs and the potential for developing prophylactic and therapeutic vaccines against HPV-associated cervical cancer using a B cell vaccine transduced with adenovirus expressing HPV16 E6/E7.

Study of Atopic Dermatitis Information on the Internet in Korea / 대한피부과학회지

BACKGROUND: The internet is an important and rapidly-evolving source of health-related information, and many patients with atopic dermatitis attempt to find information from the internet. OBJECTIVE: This study was performed to investigate the current information available on atopic dermatitis on the internet in Korea. METHODS: We chose two search engines and three community portal sites to analyze the information in which the topic of 'atopy' could be found. RESULTS: Among the 595 web sites and 1,485 communities, 97% of the web sites and 73.7% of the communities were related products or service advertisements, and some of them provided incorrect or exaggerated information. There were only 10 web sites and 20 available communities with genuine information, and most of these also presented unattested treatment methods, including alternative therapies. CONCLUSION: It is quite understandable that patients with atopic dermatitis want to seek information related to their disease, and the internet has the potential to be a useful source of information. However, there are no regulations to control the accuracy and quality of information on the internet. We should take an active role in identifying the accuracy and evaluating the quality.

Clinical Study of 28 Cases of Extramammary Paget's Disease / 대한피부과학회지

BACKGOUND: Extramammary Paget's disease (EMPD) is a rare skin neoplasm most commonly involving apocrine-bearing regions including the perineum, perianal, scrotal and vulvar areas. OBJECTIVE: The aim of this study was to identify in detail the clinical findings of EMPD in Korea. METHOD: A total of 28 patients confirmed with EMPD from July 1995 to July 2004 were included. We reviewed clinical records of the past history, clinical characteristics, and associated internal malignancy. RESULTS: In EMPD, the patients' age was from 45 to 86 years (median 64.6 years) and incidence was more frequent in men than women (23: 5, male: female). The most common predilection site was the penoscrotal area in men and the vulva in women. Two of 28 patients with EMPD had an underlying malignancy. Two of 28 patients treated with wide excision had local recurrence during the follow-up period. CONCLUSION: EMPD in Korea may be characterized by male predominance and penoscrotal location. The incidence of concomitant malignancy may be lower than that in Caucasians. However, investigation for internal malignancy and regular follow-up for recurrence is still warranted.

A Case of Bilateral Chondrodermatitis Nodularis Chronica Helicis on Both Helices Treated with Intralesional Steroid Injection / 대한피부과학회지

We report a case of bilateral chondrodermatitis nodularis chronica helicis, on both helices, in a 60-year-old male patient. He presented with a 1-year history of two tender, firm, dark-brownish, 0.4x0.4cm-sized nodules with central ulceration on both helices. He had no history of trauma. A punch biopsy specimen taken from the nodule revealed central ulceration, hyperkeratosis, and irregular acanthosis of the epidermis. Within the dermis, there was inflammatory cell infiltration, dilatation and proliferation of vessels, and some eosinophilic collagen degeneration associated with degenerative cartilage. Based on these clinical and histologic findings, we diagnosed this as a rare case of bilateral chondrodermatitis nodularis chronica helicis occurring on both helices. We treated the lesions with intralesional steroid injections.

A Case of Microcystic Adnexal Carcinoma on the Scalp / 대한피부과학회지

Microcystic adnexal carcinoma, also known as sclerosing sweat duct carcinoma, is an uncommon skin appendage neoplasm with both follicular and sweat duct differentiation. It typically occurs on the upper lip or central face of middle-aged patients but rarely affects the scalp. We report a case of microcystic adnexal carcinoma which developed on the scalp. A 65-year-old woman presented with a 10-year history of an asymptomatic, 1x1.5cm sized, firm, fixed, and dome-shaped mass on the scalp. A biopsy specimen showed a dermal tumor extending into the subcutis. Both the follicular and ductal structure, and CEA staining revealed a weakly positive reaction in the glandular structure of the tumor.

A Case of Solitary Vellus Hair Cyst on the Forehead / 대한피부과학회지

We report a case of solitary vellus hair cyst on the forehead in a 48 year-old, female patient. She had an asymptomatic, solitary, bluish, 0.3x0.3cm sized papule on the forehead for 1 year. There was no family history of similar lesions. A punch biopsy specimen taken from the papule revealed a cystic structure in the dermis lined by squamous cell epithelium which contained laminated keratinous material and vellus hairs. Based on this histologic finding, we diagnosed this case as solitary vellus hair cyst occurring on the unusual site of the forehead.