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Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is common in young Asian women under the age of 30, and is usually characterized by fever, myalgia, fatigue, and cervical lymphadenopathy. Because patients with KFD often present with necrotic lesions that are also features of lymph node metastasis, ipsilateral or bilateral lymph node enlargement in head and neck cancer patients can be disguised as lymph node metastasis. We present an unusual case of KFD mimicking bilateral metastatic papillary carcinoma of the thyroid. This study emphasizes that KFD should be considered when diagnosing lymph nodes with necrotic lesions but without malignant cells in young women.
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Nonepisodic angioedema with eosinophilia (NEAE) is a rare disease characterized by nonrecurrent angioedema with eosinophilia and normal serum IgM levels occurring predominantly in an East Asian female population. A 49-year-old male patient visited our clinic due to swelling of both the scrotums and the lower extremities, and fever. He had history of nasal polyp, cephalosporin allergy, and asthma. He was diagnosed as having NEAE and was treated with systemic corticosteroid, then he was symptom-free for more than 8 months. He had been administered omalizumab for 3 months due to uncontrolled asthma prior to the onset of angioedema which had helped taper the oral corticosteroid, and this may be associated with presentation of NEAE. Here, we report a case of NEAE in a male patient which presented with constitutional symptoms such as fever and scrotal edema
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Colloid degeneration of the skin is a rare, distinct clinicopathological entity characterized by the deposition of colloid material in the dermis. Nodular colloid degeneration (NCD) is a clinical variant of colloid degeneration of the skin. Herein, we report the case of a 40-year-old woman who presented with a 3-year history of multiple asymptomatic yellowish-brown, indurated papules and plaques on her forehead. Histopathologic examination of the lesion revealed deposition of amorphous pale pink homogenous colloid material with irregular clefts, fissures, and scattered pyknotic nuclei in the upper dermis. The material was negative for Congo red staining, and periodic acid-Schiff and Masson's trichrome staining revealed positive reactivity. Scattered fragmented elastic fibers were present in the colloid material on Verhoeff—Van Gieson staining. The patient was diagnosed with NCD. We propose that NCD should be considered in the differential diagnosis of long-standing facial nodules and plaques.
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Adulto , Femenino , Humanos , Coloides , Rojo Congo , Dermis , Diagnóstico Diferencial , Tejido Elástico , Frente , PielRESUMEN
BACKGROUND: Polydeoxyribonucleotide (PDRN) influencing cellular growth and differentiation is recognized to promote wound healing by stimulating tissue repair. Although PDRN can be extracted from human placentas, PDRN medications have recently been extracted from the semen of trout (Oncorhynchus mykiss) and salmon (Oncorhynchus keta). The present study was designed to evaluate the wound healing effects of O. keta-derived PDRN for injection (Rejuvenex) and PDRN cream (Rejuvenex Cream) in comparison with those of O. mykiss-derived PDRN injection (Placentex). METHODS: Full-thickness skin defects were made on the back of mice (n=60). The mice were divided into the following four groups according to the dressing used for the wounds: O. mykiss-derived PDRN injection group, O. keta-derived PDRN injection group, O. keta-derived PDRN cream group, and normal saline soaked dressing group (control group). We analyzed the gross findings, wound sizes, histological findings, immunohistochemistry and enzyme-linked immunosorbent assays for the groups immediately after the treatment, and again after 4, 7, and 10 days of treatment. RESULTS: The wound healing effects were the greatest in the O. keta-derived PDRN injection and O. mykiss-derived PDRN injection groups, which showed similar scores, followed by the O. keta-derived cream and normal saline soaked dressing groups. CONCLUSION: The injection of PDRN extracted from O. keta was found to be as effective at healing full-thickness skin defects as the O. mykiss-derived PDRN injection, which is currently used in the clinic. Moreover, the O. keta-derived PDRN injection was also found to reduce the time required for wound healing.
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Animales , Humanos , Ratones , Vendajes , Ensayo de Inmunoadsorción Enzimática , Inmunohistoquímica , Oncorhynchus , Placenta , Salmón , Semen , Piel , Trucha , Cicatrización de Heridas , Heridas y LesionesRESUMEN
Chondroid syringoma is a rare mixed tumor of the skin which is composed of both mesenchymal and epithelial cells. Its incidence at less than 0.1% and is frequently located on the head and neck. Chondroid syringoma is easily confused with epidermal cysts. Since malignant forms of chondroid syringoma have been reported, accurate and timely diagnosis is important for proper management. We report clinical and histological features of chondroid syringoma in 5 patients treated at our institution. In most of the cases, chondroid syringoma presented as a round, firm, nodular or cystic lesion that had well marginated heterogeneity in sonography. Clinically, all of the lesions were removed by simple excision. Microscopically, all five tumors were well circumscribed and consisted of epithelial, myoepithelial, and stromal components. The epithelial component formed tubules lined by one or more rows of eosinophilic epithelial cells. The outer layer of tubules appeared to be flattened myoepithelial cells. The stroma is myxoid and contained spindle shaped myoepithelial cells. We expect that the clinical, sonographic, and histological data from our report may help clinicians who are confronted with various kinds of analogous facial lesions to decide the most proper management for their patients.
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Humanos , Adenoma Pleomórfico , Diagnóstico , Eosinófilos , Quiste Epidérmico , Células Epiteliales , Neoplasias Faciales , Cabeza , Incidencia , Cuello , Características de la Población , Piel , Neoplasias Cutáneas , UltrasonografíaRESUMEN
Chondroid syringoma is a rare mixed tumor of the skin which is composed of both mesenchymal and epithelial cells. Its incidence at less than 0.1% and is frequently located on the head and neck. Chondroid syringoma is easily confused with epidermal cysts. Since malignant forms of chondroid syringoma have been reported, accurate and timely diagnosis is important for proper management. We report clinical and histological features of chondroid syringoma in 5 patients treated at our institution. In most of the cases, chondroid syringoma presented as a round, firm, nodular or cystic lesion that had well marginated heterogeneity in sonography. Clinically, all of the lesions were removed by simple excision. Microscopically, all five tumors were well circumscribed and consisted of epithelial, myoepithelial, and stromal components. The epithelial component formed tubules lined by one or more rows of eosinophilic epithelial cells. The outer layer of tubules appeared to be flattened myoepithelial cells. The stroma is myxoid and contained spindle shaped myoepithelial cells. We expect that the clinical, sonographic, and histological data from our report may help clinicians who are confronted with various kinds of analogous facial lesions to decide the most proper management for their patients.
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Humanos , Adenoma Pleomórfico , Diagnóstico , Eosinófilos , Quiste Epidérmico , Células Epiteliales , Neoplasias Faciales , Cabeza , Incidencia , Cuello , Características de la Población , Piel , Neoplasias Cutáneas , UltrasonografíaRESUMEN
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.
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Ensamble y Desensamble de Cromatina , Herpesvirus Humano 4 , Secuenciación de Nucleótidos de Alto Rendimiento , Histonas , Linfocitos , Linfoma , Pronóstico , Protones , Análisis de Secuencia de ADN , Linfocitos TRESUMEN
BACKGROUND/AIMS: Microscopic colitis is characterized by chronic watery diarrhea with specific pathological changes that can be diagnosed by microscopic examination. We performed immunohistochemical analysis of proinflammatory cytokines to investigate the pathogenic mechanism of microscopic colitis. METHODS: This study consisted of six patients with lymphocytic colitis, six patients with collagenous colitis, and six patients with functional diarrhea but normal pathology. We performed an immunohistochemical analysis of the colonic mucosal biopsies to assess the expression of cyclo-oxygenase-2, interleukin-17, nuclear factor-kappaB, interferon-gamma, inducible nitric oxide synthase, and tumor necrosis factor-alpha. We compared the quantity score of immunohistochemical staining among the groups. RESULTS: The microscopic colitis group showed significantly higher expression of cyclo-oxygenase-2, interleukin-17, nuclear factor-kappaB, and interferon-gamma compared with the control group. Cytokine expression was similar between collagenous colitis and lymphocytic colitis. However, the expression of cyclo-oxygenase-2 was higher in collagenous colitis. CONCLUSIONS: Proinflammatory cytokines, including interleukin-17 and interferon-gamma, are highly expressed in microscopic colitis. The expression of cyclo-oxygenase-2 was higher in collagenous colitis than in lymphocytic colitis. This study is the first on interleukin-17 expression in microscopic colitis patients.
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Humanos , Biopsia , Colitis Microscópica/metabolismo , Colon/patología , Ciclooxigenasa 2/metabolismo , Citocinas/metabolismo , Diarrea/metabolismo , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Mucosa Intestinal/patología , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
No abstract available.
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Aterosclerosis , Inflamación , Linfoma de Células B de la Zona Marginal , Arteria Renal , UréterRESUMEN
Multiple endocrine neoplasia type 1 (MEN1) syndrome includes varying combinations of endocrine and non-endocrine tumors. There are also a considerable number of atypical MEN1 syndrome. In this case, a 68-yr-old woman was referred to the Department of Endocrinology for hypercalcemia. Five years ago, she had diagnosed as primary hyperaldosteronism and now newly diagnosed as parathyroid hyperplasia with laboratory and pathologic findings. Hurthle-cell thyroid cancer was also resected during the parathyroid exploration and small meningioma was found on brain MRI. Her general condition has markedly improved and her adrenal mass and meningioma are being closely observed now. We could find the loss of heterozygosity of the MEN1 locus in parathyroid glands, suggesting a MEN1-related tumor, but not a germline mutation. Considering a variety of phenotypic expression and a limitation of current molecular analysis, periodic follow up will be needed in patients with a MEN1-like phenotype.
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Anciano , Femenino , Humanos , Secuencia de Bases , Encéfalo/diagnóstico por imagen , Hiperaldosteronismo/complicaciones , Hiperparatiroidismo Primario/diagnóstico , Pérdida de Heterocigocidad , Imagen por Resonancia Magnética , Neoplasias Meníngeas/complicaciones , Meningioma/complicaciones , Mutación , Glándulas Paratiroides/patología , Proteínas Proto-Oncogénicas/genética , Análisis de Secuencia de ADN , Neoplasias de la Tiroides/complicaciones , Tomografía Computarizada por Rayos XRESUMEN
Some cases have reported that amebic colitis leads to serious complications that are caused by a misdiagnosis of an inflammatory bowel disease and consequential ill-managed steroid therapy. Therefore, it should be stressed that the differential diagnosis on such a case is very important. Eosinophilic colitis may reveal its presence as diarrhea, abdominal pain, ascites, and eosinophilic deposits in tissues. Therefore, it is highly necessary to make a differential diagnosis to distinguish eosinophilic colitis from other infectious or inflammatory bowel diseases. We report a case of amebic colitis, which was mistakenly diagnosed as eosinophilic colitis and a liver eosinophilic abscess in a young male who complained of bloody diarrhea and right upper quadrant pain. However, the misdiagnosed steroid therapy did not aggravate the progress of the amebic infection.
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Humanos , Masculino , Dolor Abdominal , Absceso , Amoeba , Ascitis , Colitis , Diagnóstico Diferencial , Errores Diagnósticos , Diarrea , Disentería Amebiana , Eosinófilos , Enfermedades Inflamatorias del Intestino , Hígado , Absceso Hepático , EsteroidesRESUMEN
A gastric neuroendocrine carcinoma is very rare, and the histological diagnosis is very difficult. These carcinomas result in a poor prognosis because they are preceded by severe lymphovascular invasion and early metastasis. In particular, it is difficult to distinguish between adenocarcinoma and neuroendocrine carcinoma by endoscopy when no specific symptoms are present (e.g., dyspepsia, nausea). According to published articles in Korea, most cases were diagnosed as adenocarcinoma initially; however, they were confirmed postoperatively as neuroendocrine carcinoma based on a histological examination using immunohistochemical staining. A case of a 55-year-old man, who had an incidental finding of a subepithelial tumor during his health check-up, was recommended for an endoscopic submucosal dissection (ESD). But the patient was lost to follow-up for 4 years. When he was examined again, the size of the tumor had increased from the previous exam. He underwent ESD and was diagnosed with a well-differentiated neuroendocrine carcinoma.
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Humanos , Persona de Mediana Edad , Adenocarcinoma , Carcinoma Neuroendocrino , Dispepsia , Endoscopía , Hallazgos Incidentales , Corea (Geográfico) , Perdida de Seguimiento , Metástasis de la Neoplasia , PronósticoRESUMEN
BACKGROUND: Annexin A1 (ANXA1) is known to be involved in the progression and differentiation of various tumors. However, its significance and role in bladder carcinogenesis has not been fully elucidated. To determine the role ANXA1 plays in urothelial carcinoma (UC), we investigated the expression of ANXA1 protein in normal urothelial tissue, carcinoma in situ (CIS), and UC of the urinary bladder. METHODS: Protein expression level of ANXA1 and its subcellular localization were analyzed in 88 cases of UCs and corresponding 24 normal tissues and 24 CISs by immunohistochemistry. RESULTS: ANXA1 was significantly down-regulated at all subcellular localization in CIS and in the cytoplasm and membrane of cells of UC, compared to normal tissues. No significant correlation between ANXA1 expression level and tumor depth (pT), growth pattern, and recurrence was found. However, cytoplasmic and membranous ANXA1 were significantly up-regulated in high grade than in low grade UC (p=0.02 in cytoplasm and p=0.03 in membrane). CONCLUSIONS: These results suggest that ANXA1 dysregulation is involved in urothelial carcinogenesis and ANXA1 is potentially a marker for the pathologic differentiation of UC.
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Anexina A1 , Carcinoma in Situ , Citoplasma , Membranas , Recurrencia , Vejiga UrinariaRESUMEN
BACKGROUND: Many variants of dermatofibromas have been described, and being aware of the variants of dermatofibromas is important to avoid misdiagnosis. OBJECTIVE: We wanted to evaluate the clinical and pathologic characteristics of 122 cases of dermatofibromas. METHODS: We retrospectively reviewed the medical records and 122 biopsy specimens of 92 patients who were diagnosed with dermatofibroma in the Department of Dermatology at Eulji Hospital of Eulji University between January 2000 and March 2010. RESULTS: Nearly 80% of the cases occurred between the ages of 20 and 49 years, with an overall predominance of females. Over 70% of the lesions were found on the extremities. The most common histologic variant was a fibrocollagenous dermatofibroma (40.1%). Other variants included histiocytic (13.1%), cellular (11.5%), aneurysmal (7.4%), angiomatous (6.5%), sclerotic (6.5%), monster (4.9%), palisading (1.6%) and keloidal dermatofibromas (0.8%). There were 9 dermatofibromas (7.3%) that were the mixed type with two co-dominant histologic features. CONCLUSION: The results of this study are consistent with previous reports on the clinical features of dermatofibromas. However, we observed several characteristic subtypes of dermatofibroma and we compared the frequency of the histologic subtypes.
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Femenino , Humanos , Aneurisma , Biopsia , Dermatología , Extremidades , Histiocitoma Fibroso Benigno , Queloide , Registros Médicos , Estudios RetrospectivosRESUMEN
We report herein three cases of inflammatory myoglandular polyp (IMGP) presenting as hematochezia. The polyps had pedunculated, red, and smooth features, and were 12, 12, and 15 mm in diameter and located in the sigmoid colon, transverse colon, and rectum, respectively. Endoscopic polypectomies were performed. Histologic examination of the recovered specimens revealed inflammatory granulation in the lamina propria mucosa, proliferation of smooth muscle, and hyperplastic glands with cystic dilatation. The three colon polyps were finally diagnosed both clinically and histologically as IMGP. Endoscopists should bear in mind that a polyp featuring endoscopic findings of pedunculation or semipedunculation; a red, smooth, spherical, and hyperemic surface; and patchy mucosa exudation and erosion is likely to be an IMGP.
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Colon , Colon Sigmoide , Colon Transverso , Dilatación , Hemorragia Gastrointestinal , Membrana Mucosa , Músculo Liso , Pólipos , Recto , UrsidaeRESUMEN
PURPOSE: Many topical agents had been used for burn or wound treatment. An awareness of topical agents on various aspects of wound healing permits the clinician to choose the most appropriate material to advantageously control the wound process and final results. Although polydeoxyribonucleotide(PDRN) was used as a tissue repair stimulating agent in a number of human diseases, such as ulcers and burns, its wound healing effects were largely unreported. We aimed to compare the wound-healing effects of PDRN and common dressing materials on full-thickness skin defect in the mouse. METHODS: Full-thickness skin defects were made on the back of mice(N=60). The mice were divided into the following 4 groups according to the dressing used for the wounds: group O(Polydeoxyribonucleotide cream), group I (Polydeoxyribonucleotide solution), group M(Medifoam(R)), and group G(dry gauze, control group). We analyzed the gross findings, wound sizes and histological findings for the groups. RESULTS: The rate of wound size was decreased in order of group I, group O, group M and group G. The histological findings revealed that the I group showed more reepithelialization and granulation tissue formation and less inflammatory cell infiltration than the other materials. The grade score of wound healing was increased in order of group I, group O, group M and group G. CONCLUSION: PDRN applicated wound dressings can be used for treating a full-thickness skin defect wounds. Considering its superior efficacy in comparison to the efficacies of other wound dressings, PDRN soaked gauze dressing should be preferentially used for the treatment of full-thickness skin wounds.
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Animales , Humanos , Ratones , Vendajes , Quemaduras , Tejido de Granulación , Piel , Úlcera , Cicatrización de HeridasRESUMEN
PURPOSE: Iodine has been used for the prevention or management of wound infection as a topical agent. Although iodine was widely used mainly by Betadine(R) and cadexomer iodine, there was no comparative study on the efficacies of dressing methods of iodine. And also it's wound healing effect was not yet clear. The purpose of this study is to compare antibacterial effects and wound healing effects associated with various dressing methods of iodine on infected full thickness skin defect in the mouse. METHODS: One full thickness skin defects in the mice (n=60) were developed on the back and left open for twenty-four hours. Sixty mice were divided into four groups : group S(dressing with Betadine(R) soaking, n=15), group T (dressing with Betadine(R) topping, n=15), group I(dressing with Iodosorb(R), n=15), group G(control group, dressing with dry gauze, n=15). The size of the wound defects and the grades of wound healing were evaluated in 4, 7, 10 days, and antibacterial effect was evaluated with restricted zone in Mueller Hinton agar by disk diffusion method. RESULTS: After the wound was left open for twenty-four hours, many Staphylococcus aureus were cultured. The wound defect size was decreased in order of Betadine(R) soaking, Iodosorb(R), Betadine(R) topping and gauze dressing group in all days, but difference among experimental groups was not statistically significant. The grade score of wound healing was increased in order of Betadine(R) soaking, Iodosorb(R), Betadine(R) topping and gauze dressing group, and the difference was statistically significant. Antibacterial effect for S. aureus was increased in order of Iodosorb(R), Betadine(R) soaking, Betadine(R) topping and gauze dressing group, and the difference was statistically significant. CONCLUSION: Selection of the effective dressing method of iodine for infected wounds remains a controversial decision. According to this study, Iodosorb(R) may be most effective method for antibacterial effect and Betadine(R) soaking may be most effective method for infected wound healing. However, further study is necessary to evaluate the clinical efficacy of dressing methods of iodine and to search for the mechanisms that explain their effects.
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Animales , Ratones , Agar , Vendajes , Difusión , Yodo , Yodóforos , Piel , Staphylococcus aureus , Cicatrización de Heridas , Infección de HeridasRESUMEN
Enterobius vermicularis is one of the most common parasites found in the intestine of humans. The gravid female worms migrate outside the anus to release eggs on the perianal skin. Rarely, they migrate to the genitourinary tract in female patients. We present a case in which pinworm eggs were found in a cervicovaginal smear of a 37-year-old woman. The eggs were elongated oval shaped and flattened on one side. The thick, double contoured birefringent shell stained bright yellow or orange. Some coarsely granular embryos or curved larvae were enclosed in the refractile shell. Empty eggs or wrinkled shells with clumped granular material were also present. Although pinworm eggs are easily identified because of their characteristic morphologic appearance, careful screening is needed due to the frequent masking by inflammatory cells.
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Adulto , Femenino , Humanos , Canal Anal , Citrus sinensis , Huevos , Estructuras Embrionarias , Enterobius , Intestinos , Larva , Máscaras , Tamizaje Masivo , Óvulo , Parásitos , Piel , Frotis VaginalRESUMEN
BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) may cause infections during wound dressing. We aimed to compare the antibacterial activities and wound-healing effects of commercially available silver-coated or silver-impregnated wound dressings on MRSA-infected wounds. METHODS: Full-thickness skin defects were made on the back of rats (N=108) and were infected with MRSA. The rats were divided into the following 6 groups according to the dressing used for the wounds: nanocrystalline silver (Acticoat(R)), silver carboxymethylcellulose (Aquacel(R)-Ag), silver sulfadiazine (Medifoam silver(R)), nanocrystalline silver (PolyMem silver(R)), silver sulfadiazine (Ilvadon(R)), and 10% povidone iodide (Betadine(R)). We analyzed the wound sizes, histological findings, and bacterial colony counts for the groups. We also inoculated the silver materials on Mueller-Hinton agar plates containing MRSA and compared the inhibition zones in the agar plates. RESULTS: The order of the rate of wound-size decrease was Acticoat(R)>Aquacel(R)-Ag>PolyMem silver(R)>Medifoam silver(R)>Ilvadon(R)>Betadine(R). The histological findings revealed that the Acticoat(R) showed more reepithelialization and granulation tissue formation and less inflammatory cell infiltration than the other materials. The order of the time required for wound healing was Acticoat(R)>Aquacel (R)-Ag>PolyMem silver(R)>Ilvadon(R)>Medifoam silver(R)>Betadine(R). The bacterial colony counts reduced in all the groups, except in the Medifoam silver(R) group. The order of the size of the inhibition zone was Acticoat(R)>Aquacel(R)-Ag>Ilvadon(R)>PolyMem silver(R)>Betadine(R)>Medifoam silver(R). CONCLUSIONS: Silver-coated or silver-impregnated wound dressings can be used for treating MRSAinfected wounds. Considering its superior efficacy in comparison to the efficacies of other silver-coated or silver-impregnated wound dressings, Acticoat(R) should be preferentially used for the treatment of MRSA-infected skin wounds.
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Animales , Femenino , Ratas , Vendajes , Carboximetilcelulosa de Sodio/uso terapéutico , Nanopartículas del Metal/uso terapéutico , Staphylococcus aureus Resistente a Meticilina , Povidona Yodada/uso terapéutico , Ratas Sprague-Dawley , Plata/química , Sulfadiazina de Plata/uso terapéutico , Piel/patología , Infecciones Estafilocócicas/tratamiento farmacológico , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Primary malignant melanoma occurring within the male urethra is very rare. Here we report a case of malignant melanoma of the urethra in a 74-year-old man. He presented with asymptomatic gross hematuria for 5 months. His glans penis and adjacent penile skin had become discolored black 10 years ago. Cystourethroscopy showed a smooth oval-shaped elevated mass in the fossa navicularis. There were no abnormal findings in the proximal urethra and urinary bladder. Computed tomography did not detect any inguinal lymph node enlargement or distant metastases. The patient underwent partial penectomy and ilioinguinal lymph node dissection. Grossly, the distal urethra revealed an ovoid pigmented nodule, that measured 1 x 0.5 cm. Microscopic findings showed a nodular malignant melanoma arising in the urethral mucosa with pagetoid spread to the epidermis of the glans penis. There were no recurrences over a period of 12 months after surgery without chemotherapy. This is the second case of a primary malignant melanoma of the male urethra in Korea.