RESUMO
Schwannomas are slow-growing benign tumors originating from the Schwann cells of the peripheral nerve sheaths. Herein, we report the first documented case of a schwannoma presenting as a painful nipple mass in a 32-year-old woman. This mass initially developed six years ago following a period of breastfeeding. Breast magnetic resonance imaging (MRI) scans revealed an iso-intense mass, with an approximate size of 2.2 cm, on a T1-weighted image with internal cystic changes. The mass exhibited heterogeneously delayed enhancement and restricted diffusion.Surgical excision was performed, and the diagnosis of cutaneous plexiform nipple schwannoma was confirmed histopathologically. A literature review revealed that the MRI findings of the nipple mass in our case were consistent with the common features of a schwannoma.
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Sebaceous carcinoma is a malignant neoplasm frequently classified as periocular or extraocular. Extraocular sebaceous carcinoma is a relatively rare tumor commonly appearing in the head and neck region. Furthermore, extraocular sebaceous carcinoma limited to the epithelium, which is called ‘extraocular sebaceous carcinoma in situ’ is extremely rare with less than 10 cases reported in the literature. Herein, we present the case of a 93-year-old female who diagnosed as extraocular sebaceous carcinoma in situ occurring concurrently with actinic keratosis. In the present case, extraocular sebaceous carcinoma in situ as identified without any connection to an adnexal component but concurrent with actinic keratosis. This case is evidence that extraocular sebaceous carcinoma can arise from the epidermis and the tumor cells of intraepidermal squamous neoplasia can differentiate toward malignant sebocytes.
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Background@#This study aimed to investigate the capability of an automated immunohistochemical (IHC) evaluation of hormonal receptor status in breast cancer patients compared to a well-validated quantitative reverse transcription–polymerase chain reaction (RT-qPCR) method. @*Methods@#This study included 93 invasive breast carcinoma cases that had both standard IHC assay and Oncotype Dx assay results. The same paraffin blocks on which Oncotype Dx assay had been performed were selected. Estrogen receptor (ER) and progesterone receptor (PR) receptor status were evaluated through IHC stains using SP1 monoclonal antibody for ER, and 1E2 monoclonal antibody for PR. All ER and PR immunostained slides were scanned, and invasive tumor areas were marked. Using the QuantCenter image analyzer provided by 3DHISTECH, IHC staining of hormone receptors was measured and converted to histochemical scores (H scores). Pearson correlation coefficients were calculated between Oncotype Dx hormone receptor scores and H scores, and between Oncotype Dx scores and Allred scores. @*Results@#H scores measured by an automated imaging system showed high concordance with RT-qPCR scores. ER concordance was 98.9% (92/93), and PR concordance was 91.4% (85/93). The correlation magnitude between automated H scores and RT-qPCR scores was high and comparable to those of Allred scores (for ER, 0.51 vs. 0.37 [p=.121], for PR, 0.70 vs. 0.72 [p=.39]). @*Conclusions@#Automated H scores showed a high concordance with quantitative mRNA expression levels measured by RT-qPCR.
RESUMO
Sebaceous carcinoma is a malignant neoplasm frequently classified as periocular or extraocular. Extraocular sebaceous carcinoma is a relatively rare tumor commonly appearing in the head and neck region. Furthermore, extraocular sebaceous carcinoma limited to the epithelium, which is called ‘extraocular sebaceous carcinoma in situ’ is extremely rare with less than 10 cases reported in the literature. Herein, we present the case of a 93-year-old female who diagnosed as extraocular sebaceous carcinoma in situ occurring concurrently with actinic keratosis. In the present case, extraocular sebaceous carcinoma in situ as identified without any connection to an adnexal component but concurrent with actinic keratosis. This case is evidence that extraocular sebaceous carcinoma can arise from the epidermis and the tumor cells of intraepidermal squamous neoplasia can differentiate toward malignant sebocytes.
RESUMO
Background@#Eccrine porocarcinoma (EPC) is a rare malignant cutaneous adnexal tumor. Other than several scattered case reports, no comprehensive review on EPC has been conducted in Korea. @*Objective@#To clinicopathologically review all EPC cases from our institutions as well as those reported in Korea. @*Methods@#Medical records and histopathological slides of EPC cases in the skin biopsy registries of our institutions were retrospectively reviewed. Additionally, EPC cases reported in Korea before June 2019 were retrieved by searching the PubMed, KoMCI, KoreaMed, and KMbase databases. @*Results@#Nine EPC cases from our institutions were included in the study. In addition, 27 reports of 28 patients with EPC were reported in Korea. A total of 37 patients with EPC were identified, consisting of 19 males (male:female ratio, 1.06:1; mean age at diagnosis, 65.6 years). The most common site of primary tumor was the head and neck (29.7%). Wide excision was the most common (78.4%) treatment method. Initial metastasis work-up imaging studies were performed in 18 patients (48.6%), and metastasis was confirmed in eight patients (21.6%). @*Conclusion@#EPC is a rare cutaneous carcinoma in Korea. EPC usually affects elderly patients, with no sexual predilection. Due to possible metastasis, careful diagnosis and appropriate metastasis workups are warranted in EPC.
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Granulomatous reaction associated with clear cell renal cell carcinoma (CCRCC) is a rare finding, and only a few cases have been described in the literature. It is postulated to occur due to cancer-related antigenic factors such as cancer cells themselves or soluble tumor antigens shed into the blood. Herein, we describe a case of a 56-year-old male patient diagnosed with CCRCC with intratumoral granulomatous inflammation.
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Antígenos de Neoplasias , Carcinoma de Células Renais , Inflamação , Neoplasias RenaisRESUMO
PURPOSE: Breast cancer has a high prevalence in Korea. To achieve personalized therapy for breast cancer, long-term follow-up specimens are needed for next-generation sequencing (NGS) and multigene analysis. Formalin-fixed paraffin-embedded (FFPE) samples are easier to store than fresh frozen (FF) samples. The objective of this study was to optimize RNA extraction from FFPE blocks for NGS. METHODS: RNA quality from FF and FFPE tissues (n=5), expected RNA amount per unit area, the relationship between archiving time and quantity/quality of FFPE-extracted RNA (n=14), differences in quantitative real-time polymerase chain reaction (qRT-PCR) and NGS results, and comparisons of both techniques with tissue processing at different institutions (n=96) were determined in this study. RESULTS: The quality of RNA did not show any statistically significant difference between paired FF and FFPE specimens (p=0.49). Analysis of tumor cellularity gave an expected RNA amount of 33.25 ng/mm2. Archiving time affected RNA quality, showing a negative correlation with RNA integrity number and a positive correlation with threshold cycle. However, RNA from samples as old as 10 years showed a 100% success rate in qRT-PCR using short primers, showing that the effect of archiving time can be overcome by proper experiment design. NGS showed a higher success rate than qRT-PCR. Specimens from institution B (n=46), which were often stored in a refrigerator for more than 6 hours and fixed without slicing, showed lower success rates and worse results than specimens from the other institutes. CONCLUSION: Archived FFPE tissues can be used to extract RNA for NGS if they are properly processed before fixation. The expected amount of RNA per unit size calculated in this study will be useful for other researchers.
Assuntos
Humanos , Academias e Institutos , Neoplasias da Mama , Estrogênios , Seguimentos , Coreia (Geográfico) , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , RNA , Análise de SequênciaRESUMO
Perivascular epithelioid cell tumors (PEComas) refers to a family of mesenchymal neoplasms composed of angiomyolipomas, clear cell “sugar” tumors of the lung, and lymphangioleiomyomatoses. These tumors have a distinctive and common component of perivascular epithelioid cells that show an association with blood vessel walls and immunohistochemically display myomelanocytic differentiation. The unique neoplasms have been shown to have an expanded range through a variety of case reports, including visceral, intra-abdominal, soft tissue, and bone tumors. The retroperitoneum, abdominopelvic region, and uterus have been reported to be the most common sites. Most PEComas follow a benign course. However, reports of malignant PEComas are increasing. Many papers have described uterine PEComas, but to our knowledge, there have not yet been any reports of a malignant PEComa arising concomitant with another epithelial tumor and mesenchymal tumor. We report herein the case of a 67-year-old woman who experienced a malignant uterine PEComa infiltrating a preexisting intramural leiomyoma with synchronous well differentiated endometrial carcinoma and multiple liver and lung metastases.
Assuntos
Idoso , Feminino , Humanos , Angiomiolipoma , Vasos Sanguíneos , Neoplasias do Endométrio , Células Epitelioides , Leiomioma , Fígado , Pulmão , Linfangioleiomiomatose , Metástase Neoplásica , Neoplasias de Células Epitelioides Perivasculares , ÚteroRESUMO
BACKGROUND: Human papillomavirus (HPV) is a well-established oncogenic virus of cervical, anogenital, and oropharyngeal cancer. Various subtypes of HPV have been detected in 0% to 60% of breast cancers. The roles of HPV in the carcinogenesis of breast cancer remain controversial. This study was performed to determine the prevalence of HPV-positive breast cancer in Korean patients and to evaluate the possibility of carcinogenic effect of HPV on breast. METHODS: Meta-analysis was performed in 22 case-control studies for HPV infection in breast cancer. A total of 123 breast cancers, nine intraductal papillomas and 13 nipple tissues of patients with proven cervical HPV infection were tested by real-time polymerase chain reaction to detect 28 subtypes of HPV. Breast cancers were composed of 106 formalin-fixed and paraffin embedded (FFPE) breast cancer samples and 17 touch imprint cytology samples of breast cancers. RESULTS: The overall odds ratio between breast cancer and HPV infection was 5.43 (95% confidence interval, 3.24 to 9.12) with I2 = 34.5% in meta-analysis of published studies with case-control setting and it was statistically significant. HPV was detected in 22 cases of breast cancers (17.9%) and two cases of intaductal papillomas (22.2%). However, these cases had weak positivity. CONCLUSIONS: These results failed to serve as significant evidence to support the relationship between HPV and breast cancer. Further study with larger epidemiologic population is merited to determine the relationship between HPV and breast cancer.
Assuntos
Humanos , Neoplasias da Mama , Mama , Carcinogênese , Estudos de Casos e Controles , Mamilos , Razão de Chances , Vírus Oncogênicos , Neoplasias Orofaríngeas , Papiloma , Papiloma Intraductal , Parafina , Prevalência , Reação em Cadeia da Polimerase em Tempo RealRESUMO
PURPOSE: The S100 gene family, which comprises over 20 members, including S100A1, S100A2, S100A8, S100A9, profilaggrin, and hornerin encodes low molecular weight calcium-binding proteins with physiological and pathological roles in keratinization. Recent studies have suggested a link between S100 proteins and human cancer progression. The purpose of the present study was to determine the expression levels of hornerin, S100A8, and S100A9 and evaluate their roles in the progression of invasive ductal carcinoma (IDC). METHODS: Seventy cases of ductal carcinoma in situ (DCIS), IDC, and metastatic carcinoma in lymph nodes (MCN) were included. Tissue microarrays were constructed from lesions of DCIS, IDC, and MCN from the same patients. Expression of hornerin, S100A8, and S100A9 was analyzed using immunohistochemistry. RESULTS: The expression of hornerin was associated with the estrogen receptor-negative (p=0.003) and the human epidermal growth factor receptor 2-positive (p=0.002) groups. The expression of S100A8 was associated with a higher pT stage (p=0.017). A significant (p0.050) different. The expression of hornerin increased in a stepwise manner (DCISAssuntos
Humanos
, Neoplasias da Mama
, Mama
, Proteínas de Ligação ao Cálcio
, Carcinoma Ductal
, Carcinoma Intraductal não Infiltrante
, Estrogênios
, Imuno-Histoquímica
, Linfonodos
, Peso Molecular
, Receptores ErbB
, Proteínas S100
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BACKGROUND: SIRT7 is one of the histone deacetylases and is NAD-dependent. It forms a complex with ETS-like transcription factor 4 (ELK4), which deacetylates H3K18ac and works as a transcriptional suppressor. Overexpression of SIRT7 and deacetylation of H3K18ac have been shown to be associated with aggressive clinical behavior in some cancers, including hepatocellular carcinoma (HCC). The present study investigated the immunohistochemical expression of SIRT7, H3K18ac, and ELK4 in hepatocellular carcinoma. METHODS: A total of 278 HCC patients were enrolled in this study. Tissue microarray blocks were made from existing paraffin-embedded blocks. Immunohistochemical expressions of SIRT7, H3K18ac and ELK4 were scored and analyzed. RESULTS: High SIRT7 (p = .034), high H3K18ac (p = .001), and low ELK4 (p = .021) groups were associated with poor outcomes. Age < 65 years (p = .028), tumor size ≥ 5 cm (p = .001), presence of vascular emboli (p = .003), involvement of surgical margin (p = .001), and high American Joint Committee on Cancer stage (III&V) (p < .001) were correlated with worse prognoses. In multivariate analysis, H3K18ac (p = .001) and ELK4 (p = .015) were the significant independent prognostic factors. CONCLUSIONS: High SIRT7 expression with poor overall survival implies that deacetylation of H3K18ac contributes to progression of HCC. High H3K18ac expression with poor prognosis is predicted due to a compensation mechanism. In addition, high ELK4 expression with good prognosis suggests another role of ELK4 as a tumor suppressor beyond SIRT7's helper. In conclusion, we could assume that the H3K18ac deacetylation pathway is influenced by many other factors.
Assuntos
Humanos , Carcinoma Hepatocelular , Compensação e Reparação , Histona Desacetilases , Imuno-Histoquímica , Articulações , Análise Multivariada , Prognóstico , Fatores de TranscriçãoRESUMO
Benign perivascular epithelioid cell tumor (PEComa) of the lung is a rare benign neoplasm, a sclerosing variant of which is even rarer. We present a case of 51-year-old man who was diagnosed with benign sclerosing PEComa by percutaneous fine needle aspiration cytology and biopsy. The aspirate revealed a few cell clusters composed of bland-looking polygonal or spindle cells with fine granular or clear cytoplasm. Occasional fine vessel-like structures with surrounding hyalinized materials were seen. The patient later underwent wedge resection of the lung. The histopathological study of the resected specimen revealed sheets of polygonal cells with clear vacuolated cytoplasm, variably sized thin blood vessels, and densely hyalinized stroma. In immunohistochemical studies, reactivity of tumor cells for human melanoma black 45 and Melan-A further supported the diagnosis of benign sclerosing PEComa. To the best of our knowledge, this is the first case of benign sclerosing PEComa described in lung.
Assuntos
Humanos , Pessoa de Meia-Idade , Biópsia , Biópsia por Agulha Fina , Vasos Sanguíneos , Citoplasma , Diagnóstico , Células Epitelioides , Hialina , Neoplasias Pulmonares , Pulmão , Antígeno MART-1 , Melanoma , Neoplasias de Células Epitelioides Perivasculares , Nódulo Pulmonar SolitárioRESUMO
BACKGROUND: Identification of poor prognostic factors in papillary thyroid carcinoma (PTC) patients is important for the patients' care and follow-up. We can sometimes see small tumor clusters without desmoplasia and no evidence of lymphatic emboli around the main tumor mass of PTC. We termed this form of tumor clustering, 'tumor sprouting,' and determined whether these tumors correlate with lymphovascular invasion, lymph node metastasis, and recurrence. METHODS: We analyzed a total of 204 cases of papillary thyroid macrocarcinoma. Number, size and distance from the main tumor of the tumor sprouting were observed and analyzed with clinicopathologic characteristics. RESULTS: Tumor sprouting was observed in 101 patients. Presence of tumor sprouting was significantly associated with positive resection margin (p=.002), lymphovascular invasion (p=.001), lymph node metastasis (p<.001), and recurrence (p=.004). Univariate analysis of recurrence-free survival revealed that tumor multiplicity (p=.037), positive resection margin (p=.007), lymphovascular invasion (p=.004), lymph node metastasis (p<.001), and tumor sprouting (p=.004) were poor prognostic factors. In multivariate analysis, positive resection margin was an independent poor prognostic factor of recurrence. CONCLUSIONS: In conclusion, tumor sprouting is significantly correlated with lymph node metastasis and recurrence. Evaluation of tumor sprouting in PTC patients could be helpful in predicting tumor recurrence or lymph node metastasis.
Assuntos
Humanos , Seguimentos , Linfonodos , Análise Multivariada , Metástase Neoplásica , Recidiva , Glândula Tireoide , Neoplasias da Glândula TireoideRESUMO
BACKGROUND: Silent mating type information regulation 2 homolog 1 (SIRT1), an NAD+-dependent deacetylase, might act as a tumor promoter by inhibiting p53, but may also as a tumor suppressor by inhibiting several oncogenes such as beta-catenin and survivin. Deleted in breast cancer 1 (DBC1) is known as a negative regulator of SIRT1. METHODS: Immunohistochemical expressions of SIRT1, DBC1, beta-catenin, surviving, and p53 were evaluated using 2 mm tumor cores from 349 colorectal cancer patients for tissue microarray. RESULTS: Overexpression of SIRT1, DBC1, survivin, and p53 was seen in 235 (67%), 183 (52%), 193 (55%), and 190 (54%) patients, respectively. Altered expression of beta-catenin was identified in 246 (70%) patients. On univariate analysis, overexpression of SIRT1 (p=0.029) and altered expression of beta-catenin (p=0.008) were significantly associated with longer overall survival. Expression of SIRT1 was significantly related to DBC1 (p=0.001), beta-catenin (p=0.001), and survivin (p=0.002), but not with p53. On multivariate analysis, age, tumor stage, differentiation, and expression of SIRT1 were independent prognostic factors significantly associated with overall survival. CONCLUSIONS: SIRT1 overexpression is a good prognostic factor for colorectal cancer, and SIRT1 may interact with beta-catenin and survivin rather than p53.
Assuntos
Humanos , Adenocarcinoma , beta Catenina , Neoplasias da Mama , Colo , Neoplasias Colorretais , Análise Multivariada , Oncogenes , Prognóstico , Sirtuína 1RESUMO
BACKGROUND: Overexpression of heat shock protein 70 (HSP70) has been observed in many types of cancer including gastric adenocarcinomas, although the exact role of HSP70 in carcinogenesis remains unclear. METHODS: The study analyzed a total of 458 radical gastrectomy specimens which were immunohistochemically stained with HSP70, p53, and Ki-67 antibodies. RESULTS: The study determined that the expression of HSP70 was significantly increased in early gastric cancer (EGC) compared to advanced gastric cancer (p<0.001). The HSP70 expression was correlated with well-differentiated tumor type, intestinal type of Lauren classification and the lower pT and pN stage. Negative expression of Ki-67 and p53 expression was associated with poor prognosis. The study did not find any correlation between HSP70 and p53 expression. The study determined that HSP70 expression in the EGC subgroup was associated with a poor prognosis (p=0.009), as well as negative Ki-67 expression (p=0.006), but was not associated with p53. Based on multivariate analysis, HSP70 expression (p=0.024), negative expression of Ki-67, invasion depth and lymph node metastasis were determined to be independent prognostic markers. CONCLUSIONS: HSP70 is expressed in the early stages of gastric adenocarcinoma. In EGC, HSP70 is a poor independent prognostic marker and is correlated with a low proliferation index.
Assuntos
Adenocarcinoma , Gastrectomia , Proteínas de Choque Térmico , Temperatura Alta , Proteínas de Choque Térmico HSP70 , Antígeno Ki-67 , Linfonodos , Análise Multivariada , Metástase Neoplásica , Prognóstico , Neoplasias GástricasRESUMO
BACKGROUND: Sirtuin 1 (SIRT1) and deleted in breast cancer 1 (DBC1) are known as tumor suppressor or promoter genes. This may be due to their diverse functions and interaction with other proteins. Gastric adenocarcinoma is one of the most common malignancies, but little is known about its carcinogenesis. Therefore, we investigated the association of immunohistochemical expression of SIRT1, DBC1, p53, and beta-catenin and their variable clinicopathological characteristics. METHODS: We obtained samples from 452 patients who underwent gastrectomy. Tissue microarray blocks were constructed and immonohistochemical staining was performed. RESULTS: Expression of DBC1 and SIRT1 was associated with lower histologic grade, intestinal type of Lauren classification, and lower pT (p<0.001) and pN stage (DBC1, p=0.002; SIRT1, p<0.001). Association between absence of lymphatic invasion, and SIRT1 (p=0.001) and DBC1 (p=0.004) was observed. Cytoplasmic beta-catenin expression was associated with lower histologic grade, pT, pN, tumor-node-metastasis (TNM) stage, DBC1 (p<0.001), and SIRT1 (p=0.001). Expression of SIRT1 and DBC1 was not associated with p53 (p=0.063 and p=0.060). DBC1 was an independent good prognostic factor in multivariate analysis (p=0.012). CONCLUSIONS: SIRC1 and DBC1 can be considered to be good prognostic factors in gastric adenocarcinoma.
Assuntos
Humanos , Adenocarcinoma , beta Catenina , Neoplasias da Mama , Citoplasma , Gastrectomia , Análise Multivariada , Proteínas , Sirtuína 1 , Estômago , Proteínas Supressoras de TumorRESUMO
Carcinosarcoma of the colon is rare. Seventeen cases have been reported in the English literature. Most cases occurred in the left side of the colon. Indeed, there is only one reported case of cecal carcinosarcoma. Carcinosarcoma has a tendency to distantly metastasize and shows dismal prognosis. We report a case of carcinosarcoma in the cecum and review the literature describing colonic carcinosarcoma.
Assuntos
Carcinossarcoma , Ceco , Colo , Colo Ascendente , PrognósticoRESUMO
Recent evidence has suggested that human skin fibroblasts may represent a novel source of therapeutic stem cells. In this study, we report a 3-stage method to induce the differentiation of skin fibroblasts into insulin-producing cells (IPCs). In stage 1, we establish the isolation, expansion and characterization of mesenchymal stem cells from human labia minora dermis-derived fibroblasts (hLMDFs) (stage 1: MSC expansion). hLMDFs express the typical mesenchymal stem cell marker proteins and can differentiate into adipocytes, osteoblasts, chondrocytes or muscle cells. In stage 2, DMEM/F12 serum-free medium with ITS mix (insulin, transferrin, and selenite) is used to induce differentiation of hLMDFs into endoderm-like cells, as determined by the expression of the endoderm markers Sox17, Foxa2, and PDX1 (stage 2: mesenchymal-endoderm transition). In stage 3, cells in the mesenchymal-endoderm transition stage are treated with nicotinamide in order to further differentiate into self-assembled, 3-dimensional islet cell-like clusters that express multiple genes related to pancreatic beta-cell development and function (stage 3: IPC). We also found that the transplantation of IPCs can normalize blood glucose levels and rescue glucose homeostasis in streptozotocin-induced diabetic mice. These results indicate that hLMDFs have the capacity to differentiate into functionally competent IPCs and represent a potential cell-based treatment for diabetes mellitus.
Assuntos
Animais , Feminino , Humanos , Camundongos , Biomarcadores/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular , Proliferação de Células/efeitos dos fármacos , Separação Celular , Células Cultivadas , Derme/citologia , Diabetes Mellitus Experimental/cirurgia , Fibroblastos/citologia , Genitália Feminina/citologia , Glucose/metabolismo , Fator 3-beta Nuclear de Hepatócito/metabolismo , Proteínas de Homeodomínio/metabolismo , Insulina/farmacologia , Células Secretoras de Insulina/citologia , Transplante das Ilhotas Pancreáticas , Células-Tronco Mesenquimais/citologia , Camundongos Nus , Niacinamida/farmacologia , Recuperação de Função Fisiológica , Fatores de Transcrição SOXF/metabolismo , Selenito de Sódio/farmacologia , Transativadores/metabolismo , Transferrina/farmacologiaRESUMO
Ovarian primary malignant melanoma is very uncommon with only 44 reported cases in the literature. A 71-year-old woman with an ovarian mass and multiple nodules in the liver presented to our hospital. She was treated with bilateral salpingo-oophorectomy, and malignant melanoma was found in the mature cystic teratoma of the ovary. Malignant melanoma cells were also found in the ascitic fluid. She died 5 months later. Here we report a very uncommon case of malignant melanoma arising in an ovarian mature cystic teratoma with a review of the literature.
Assuntos
Idoso , Feminino , Humanos , Líquido Ascítico , Fígado , Melanoma , Ovário , TeratomaRESUMO
Composite pheochromocytoma or paraganglioma of the adrenal gland is a well-recognized, yet extremely rare tumor with only one case reported in Korea. We report a case of incidentally found composite pheochromocytoma and ganglioneuroma of the adrenal gland in a 44-year-old female composed of intermingled components of pheochromocytom, ganglioneuroma, and cells with intermediate features. On immunohistochemical staining, the pheochromocytoma component was positive for synaptophysin and chromogranin, but negative for S-100 protein. Staining for the S-100 protein revealed sustentacular cells which formed a peripheral coat around the "Zellballen" and Schwann cells. The Fontana-Masson stain defined neuromelanin granules of ganglion cells and the ganglion cells expressed neural markers such as neurofilament proteins. Ultrastructural findings revealed pheochromocytes with a round or ovoid nucleus and occasionally prominent nucleolus containing numerous adrenaline and noradrenaline granules.