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Jae Y Ro

Publications and source records attributed to Jae Y Ro.

69 records · Page 4Linked to original sources
PubMed2002

Extranodal follicular dendritic cell sarcoma of the head and neck region: three new cases, with a review of the literature.

Extranodal follicular dendritic cell (FDC) sarcoma of the head and neck region is uncommon, with 16 well-documented cases previously reported (four in the tonsil, four in the pharynx, two in the palate, five in the soft tissue, and one in the thyroid). We here report an additional three cases of extranodal FDC sarcoma in the tonsil (two cases) and pharynx (one case). In these new cases, the neoplastic cells were arranged in diffuse, fascicular, and vaguely whorled growth patterns. A background lymphocytic infiltrate was sprinkled throughout the neoplasms, with focal prominent perivascular cuffing. Scattered multinucleated giant cells were present. Immunohistochemically, tumor cells were strongly and diffusely positive for follicular dendritic cell markers CD21 and CD35. Tumor cells were diffusely positive for fascin and negative for leukocyte common antigen, S-100 protein, cytokeratin, and Epstein-Barr virus (EBV) latent membrane protein-1 (EBV-LMP). EBV was also not detected in the tumor cells by in situ hybridization for EBV-encoded RNAs. FDC sarcomas are probably an underrecognized neoplasm, especially when they occur in extranodal sites in the head and neck region. Two of the three new cases we report were initially misdiagnosed, and five cases of extranodal FDC sarcoma in the head and neck region reported in the recent literature were initially misdiagnosed. Our aim is to complement the current understanding of this neoplasm and alert pathologists to this rare entity in this region to avoid misdiagnosis. Recognition of extranodal FDC sarcoma requires a high index of suspicion, but this tumor has numerous distinctive histological features that should bring the neoplasm into the differential diagnosis. Confirmatory immunohistochemical staining with follicular dendritic cell markers such as CD21 and/or CD35 is essential for the diagnosis. Correct characterization of this neoplasm is imperative given its potential for recurrence and metastasis.

Adult↗
PubMed2002

Profile of methylated CpG sites of hMLH1 promoter in primary gastric carcinoma with microsatellite instability.

A recent study using colorectal cancer cell lines has identified methylation on a small region of hMLH1 promoter (-248 to -178 relative to the transcription start site) to be critical for gene silencing, but shown that methylation on a more upstream region is frequent in cell lines with hMLH1 expression. Because cultured cell lines have a higher degree of CpG methylation than primary tumors, we attempted to examine methylation profiles of CpG sites of hMLH1 promoter in primary gastric carcinomas with or without microsatellite instability (MSI). Seven cases with MSI and six cases without MSI were assessed for the methylation status of hMLH1 promoter by bisulfite-sequencing. All of the MSI-positive cases previously showed loss of hMLH1 expression and six cases displayed methylated alleles in methylation-specific PCR (MSP) for hMLH1. Sequencing analysis revealed that: (i) CpG sites were overall methylated in MSI-positive tumors with positive MSP results; (ii) a small region (-248-178) was almost invariably methylated in MSI-positive tumors; and (iii) the vast majority of CpG sites were unmethylated in MSI-negative tumors, including a more upstream region (proximal to -248). Our study suggests that methylation of a more upstream region observed in colon cancer cell lines may be an acquired change during cell line establishment and it was not identified in primary gastric carcinomas without MSI.

Adaptor Proteins, Signal Transducing↗
PubMed2002

Adenocarcinomas of the gastrointestinal tract with prominent rhabdoid features.

Rhabdoid tumor, first described in kidneys of infants and children, is an aggressive tumor that has been reported in several extrarenal locations. Gastrointestinal tumors with rhabdoid features are extremely rare. The effect of the rhabdoid phenotype on the aggressiveness of gastrointestinal tumors remains unclear. We present four cases of rhabdoid tumors of the gastrointestinal tract involving the esophagus, stomach, and small intestine and discuss the clinicopathologic, immunohistochemical, and ultrastructural features. In the four cases reported herein, the patients' ages ranged from 52 to 73 years, and tumor size ranged from 3.8 to 13 cm in greatest dimension. The noncohesive rhabdoid cells exhibited an eccentric nucleus with a paranuclear inclusion, which was shown by electron microscopic examination to be composed of intermediate filaments. On immunohistochemical staining, the tumor cells were positive for vimentin and cytokeratin. Three patients developed distant metastasis shortly after diagnosis and died of disease within 2 to 10 months after initial presentation. A retrospective review of outcomes of the current cases and previously published literature showed that 12 (75%) of the 16 patients died within 6 months of presentation. Recognition of the rhabdoid phenotype in gastrointestinal tract neoplasms is important because this feature is associated with poor prognosis and unresponsiveness to conventional therapy.

Adenocarcinoma↗
PubMed2002

Apoptosis in thymic epithelial tumors.

We studied Fas/FasL, Bcl-2, and M30 CytoDeath in five cases of normal thymus and 41 cases of thymic epithelial tumors (TETs). In normal thymus, Fas was expressed in all epithelial cells, but not in thymic lymphocytes; FasL was weakly expressed only in medullary epithelium and Hassal's corpuscles. In TETs, Fas was expressed in all epithelial cells and lymphocytes, while FasL was differently expressed in epithelial cells of different subtypes of TETs, i.e., type A (2/2), AB (12/12), B1 (0/9), B1/B2 (0/3), B2 (0/1), B2/B3 (1/3), B3 (6/10) and C (1/1), but not in lymphocytes. Bcl2 protein was strongly expressed in medullary-derived lymphocytes of normal thymus and TETs, and weakly expressed only in medullary (spindle) epithelium of TETs. On M30 CytoDeath immunostaining, apoptotic indices were very low in all TETs (0-1.2). In conclusion, since FasL was expressed on the epithelial cells of lymphocyte-depleted (LD) areas of type B2/B3 and/or LD subtypes (type A, AB, B3, C), FasL expression could be relevant for the intracytoplasmic processes of T-cell selection and the regulation of the lymphoid cells inside the tumor, at least partly. However, tumorigenesis of TETs is not necessarily induced by abrogation of apoptosis.

Adolescent↗
PubMed2002

Primary Ewing's sarcoma/primitive neuroectodermal tumor of the kidney: a clinicopathologic and immunohistochemical analysis of 11 cases.

Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is an extraordinarily rare primary tumor in the kidney and can be mistaken for a variety of other round cell tumors, including blastema-predominant Wilms' tumor (WT). Approximately 90% of ES/PNET have a specific t(11;22), which results in a chimeric EWS-FLI-1 protein. Immunohistochemistry for the carboxy-terminus of FLI-1 is sensitive and highly specific for the diagnosis of ES/PNET. WT-1, the WT-associated tumor suppressor gene, is overexpressed in WT but not in ES/PNET. No study has examined FLI-1 or WT-1 expression in renal ES/PNET. The clinicopathologic features of 11 renal ES/PNET were studied along with immunohistochemistry for cytokeratin, desmin, CD99, FLI-1, and WT-1. WT were also immunostained for CD99 (5 cases), FLI-1 (10 cases), and WT-1 (9 cases). The patients (6 men, 5 women) ranged from 18 to 49 years of age (mean, 34 yr). The mean tumor size was 11.8 +/- 3.8 cm (mean +/- standard deviation). Presenting symptoms included abdominal/flank pain and/or hematuria. Grossly, all tumors showed necrosis and hemorrhage, and 4 had cystic change. Microscopically, all tumors showed vaguely lobular growth, primitive round cells, and variable rosette formation. Epithelial, myogenous, or cartilaginous differentiation was not seen. Immunohistochemical results on the renal ES/PNET were cytokeratin (2/8 focal), desmin (0/9), CD99 (8/8), FLI-1 (5/8), and WT-1 (0/8). In comparison, the WT only rarely expressed CD99 (1/5) and did not express FLI-1 (0/10), but were usually WT-1-positive (7/9). Follow-up on 8 cases (mean, 28 mo; range, 6-64 mo) showed 4 lung and pleural metastases, 1 bone metastasis, liver metastasis, 2 local recurrences, and 5 deaths from disease (median time to death, 16.8 mo). No case had distant metastatic disease at presentation. Adjuvant therapy included chemotherapy (8 cases), radiation (3 cases), and bone marrow transplantation (1 case). Our study affirms a unique proclivity of renal ES/PNET for young adults and that it is a highly aggressive neoplasm, with rapid death in many cases, usually after the development of treatment-resistant lung metastases. These tumors must be distinguished from blastema-predominant WT and other primitive renal tumors that require different therapy. FLI-1 and WT-1 immunohistochemistry may be valuable in this differential diagnosis, given the known immunophenotypic overlap between ES/PNET and blastema-predominant WT with regard to CD99, cytokeratin, and desmin. The accurate distinction between these two entities has clear prognostic and therapeutic implications.

12E7 Antigen↗
PubMed2002

Micropapillary component in lung adenocarcinoma: a distinctive histologic feature with possible prognostic significance.

Micropapillary carcinoma or a micropapillary carcinoma component has been reported in the ovary, breast, and urinary bladder and is generally thought to have prognostic significance. However, little has been written on micropapillary differentiation in lung carcinoma. We studied 35 cases of primary lung adenocarcinoma with a micropapillary component seen at the M.D. Anderson Cancer Center. The micropapillary component in these tumors ranged from focal to prominent and was seen at both primary and metastatic sites. This component was not associated with any particular histologic subtype of lung adenocarcinoma. Of the 15 cases with available material, 14 (93%) stained positive for cytokeratin 7, whereas only two of the 15 cases (13%) stained positive for cytokeratin 20. Thyroid transcription factor-1 immunostaining of tumor nuclei was seen in 12 of the 15 cases (80%). Immunostaining was seen in areas both with and without micropapillary differentiation. Thirty-three of 35 patients (94%) developed metastases, which occurred most commonly in the lymph nodes (n = 26), and also in the lung (n = 17), brain (n = 9 cases), bone (n = 9 cases), and other sites. Most metastases had a prominent micropapillary component, irrespective of the extent of the micropapillary carcinoma component in the primary lung tumor. Adequate clinical follow-up information was available for 29 patients. The mean follow-up was 25 months. At their last follow-up, 16 of 29 patients (55%) were still alive with disease, 5 (17%) were dead of disease, and 8 (28%) were alive with no evidence of disease. We believe that a micropapillary component occurring in lung adenocarcinoma should be reported, as this component may be more likely to metastasize. The presence of this component should alert the clinician to search more carefully for metastases and have a closer follow-up on these patients. It is also important to recognize this component in evaluating a metastasis from an unknown primary site, as it should alert the pathologist to a possible primary in the lung in addition to breast, urinary bladder, and ovary.

Adenocarcinoma↗
PubMed2002

Nodular histiocytic hyperplasia of the endometrium.

We describe the clinical and pathologic features of four cases of nodular histiocytic proliferation in the endometrium. We have been able to find only one brief reference to this lesion in the literature. The lesion in each case was a detached nodule composed of aggregates of histiocytes within a biopsy or curettage specimen. The constituent cells differed from foamy histiocytes of the endometrium in that they had either lobulated or ovoid, vesicular nuclei, distinctive cytoplasmic margins, and a moderate amount of amphophilic cytoplasm. Mitoses were frequent (up to 11 per 10 high-power fields) in one case but were absent in the remaining cases. On immunohistochemical staining, CD68 and lysozyme were strongly expressed in the cytoplasm. Neither estrogen receptor nor progesterone receptor was expressed in contrast to the background endometrium. The cells were also negative for S-100 and cytokeratin. Each patient's postcurettage course was uneventful. The cause of nodular histiocytic proliferation of the endometrium is currently unknown, although response to intracavitary debris has been suggested. The lesion should not be confused with a variety of reactive, inflammatory, or neoplastic conditions, such as xanthogranulomatous endometritis, malakoplakia, histiocytic granuloma, hormonal changes of the endometrial stroma, Langerhans' cell histiocytosis, morular metaplasia, extravillous trophoblast, or exaggerated placental site reaction.

Adult↗
PubMed2002

Synchronous hepatocellular carcinoma and cholangiocarcinoma arising in two different dysplastic nodules.

We present the first reported case of explant cirrhotic liver that had synchronous cholangiocarcinoma and hepatocellular carcinoma arising in two different high-grade dysplastic nodules. The patient was a 55-year-old woman who had hepatitis B virus-associated liver cirrhosis for 3 years. The moderately differentiated cholangiocarcinoma occurred in high-grade dysplastic nodule with a 1.7-fold cell density compared with that of cirrhotic nodule. The hepatocellular carcinoma arose in a nodule-in-nodule pattern within a peripherally low-grade and centrally high-grade dysplastic nodule and had a 2.7-fold cell density compared with that of cirrhotic nodule. By immunohistochemistry, the tumor cells of the cholangiocarcinoma as well as bile ductular cells in dysplastic nodule were diffusely positive for cytokeratin 7, whereas hepatocellular carcinoma cells and dysplastic hepatocytes were negative for cytokeratin 7. The c-kit-positive hepatic progenitor cells were singly scattered between hepatocytes, and their number was highest in cirrhotic nodule and decreased in dysplastic nodule, whereas they were absent in cholangiocarcinoma and hepatocellular carcinoma arising in dysplastic nodules. Proliferation indices were progressively increased in cirrhotic nodule, dysplastic nodule, and cholangiocarcinoma or hepatocellular carcinoma, sequentially. These observations indicate that cholangiocarcinoma as well as hepatocellular carcinoma can develop in dysplastic nodule and that hepatic progenitor cells might play a role in the early stage of cholangiocarcinogenesis and hepatocarcinogenesis.

Bile Duct Neoplasms↗
PubMed2002

True hermaphroditism and mixed gonadal dysgenesis in young children: a clinicopathologic study of 10 cases.

True hermaphroditism (TH) refers to individuals who have both unequivocal ovarian tissue and testicular elements regardless of their karyotypes; whereas mixed gonadal dysgenesis (MGD) refers to individuals who usually have a differentiated gonad on one side and a streak gonad or streak testis on the other side. A differential diagnosis between the TH and MGD has important clinical implications for gender assignment and the decision for early gonadectomy; however, variable clinical and histological features frequently lead to the confusion of TH with MGD. We reviewed the clinicopathological features of TH (n = 4) and MGD (n = 6) in young children to identify which morphological features are important for a differential diagnosis between the two conditions. In both conditions, the testicular compartment was composed of immature seminiferous tubules lined by immature Sertoli cells and primitive germ cells; this finding was not helpful for a differential diagnosis. The ovarian compartment in TH cases showed numerous primordial follicles containing primary oocytes with a few primary or antral follicles; however, ovarian compartments in patients with MGD were characterized by primitive sex-cordlike structures with or without germ cell components within the ovarian-type stroma, mimicking gonadoblastomas in two cases and granulosa cell or Sertoli cell tumors in three cases. Hormonal profiles, cytogenetic results, and an internal duct system were not helpful in a differential diagnosis. In conclusion, a differential diagnosis between TH and MGD is largely dependent on the histological features of the gonads. Therefore, examination of all resected or biopsied tissue and the application of strict histological criteria are important.

Child, Preschool↗
PubMed2002

The morphologic spectrum of metastatic prostatic adenocarcinoma to the lung: special emphasis on histologic features overlapping with other pulmonary neoplasms.

We undertook a detailed histologic study to identify specific morphologic features that may aid in distinguishing prostatic adenocarcinoma with lung metastases (PALM) from other pulmonary tumors with similar histologic features. In 16 cases, we found 3 predominant architectural patterns: microacinar (n = 10), tubulopapillary (ductal; n = 4), and carcinoid-like (n = 2). Characteristic features of PALM included small acinar and/or cribriform growth, frequent lymphangitic permeation, lack of stromal response, uniform round nuclei with prominent nucleoli, intraluminal blue mucin, and prominent cell borders. By immunohistochemical staining, prostate-specific antigen and prostate-specific acid phosphatase were present in 13 of 14 and 13 of 13 cases, respectively. Metastatic prostatic duct adenocarcinoma exhibited morphologic features similar to metastatic colonic adenocarcinoma. Two cases had a carcinoid-like appearance with nested or solid architecture, parachromatin clearing, and prominent nucleoli, but lacked the finely stippled chromatin pattern of carcinoid tumors. Several features that may result in misinterpretation or lack of association of the neoplasm in the lung with a prostatic primary include lung metastasis preceding the detection of a prostatic primary tumor, solitary pulmonary nodule, tubulopapillary (ductal) or carcinoid-like pattern, scant material in which histologic features of metastatic prostate carcinoma are not fully appreciated, and frequent necrosis. Attention to specific discriminating histologic features, supported by immunohistochemical staining, may be useful in the differential diagnosis, which is therapeutically and prognostically critical.

Acid Phosphatase↗
PubMed2002

Myelolipoma associated with adrenal ganglioneuroma.

Adrenal myelolipomas are rare, benign mesenchymal tumors composed of mature adipose tissue and hematopoietic cells in varying proportions. Although the majority of cases occur as isolated adrenal lesions, myelolipomas have been described in association with various adrenal pathologic conditions. These conditions include enzyme deficiencies and hyperplastic and neoplastic lesions of the adrenal cortex, with perhaps endocrine dysfunction as a common feature. Ganglioneuroma is a benign tumor of the sympathetic nervous system that rarely produces symptoms of endocrine dysfunction. We report an unusual case of myelolipoma associated with ganglioneuroma of the adrenal medulla. The histogenesis of myelolipoma remains speculative. However, the close proximity to adrenal cortical cells within the stroma of ganglioneuroma suggests that the hormonal microenvironment may have played a role in the development of the myelolipoma.

Adrenal Gland Neoplasms↗
PubMed2000

Mesenchymal Chondrosarcoma: A Small Cell Neoplasm with Polyphenotypic Differentiation.

We analyzed the clinicoradiographic, microscopic, and immunophenotypic features of 21 tumors from 13 patients with mesenchymal chondrosarcoma (11 primary and 10 metastatic) and addressed the issue of their potential polyphenotypic differentiation. The immunophenotypic profile of the tumors was analyzed by studying the expressions of the MIC2 gene protein (p30/32(MIC2)), S-100 protein, desmin, myoD1, myogenin, myoglobin, smooth-muscle actin, cytokeratin, neuron-specific enolase, and HMB-45. The expression of p30/32(MIC2) was typically restricted to the small cell component of the mesenchymal chondrosarcoma and could be documented in 17 tumors. The cartilaginous areas were positive for S-100 protein in 20 tumors. Scattered positivity of small cells for desmin was seen in 8 cases. In 2 primary tumors from different patients (1 intraosseous and 1 extraskeletal) a diffuse expression of desmin with focal coexpression of myoD1 was present within the small cell component of the tumor. The positivity for smooth-muscle actin was documented in 2 cases. Either the small cell or cartilaginous components were at least focally positive for neuron-specific enolase in 11 tumors. All tumors were negative for myogenin, myoglobin, cytokeratins (AE1/AE3, CAM5.2) and HMB-45. This study showed that, in addition to cartilaginous differentiation, mesenchymal chondrosarcomas may exhibit focal expression of desmin. In rare cases more diffuse rhabdomyoblastic differentiation can be seen within the small cell component of the tumor. Thus, mesenchymal chondrosarcoma is another primitive neoplasm with polyphenotypic differentiation and features that overlap those of other small cell malignances of bone and soft tissue. Int J Surg Pathol 8(4):291-301, 2000

Journal Article↗
PubMedDate not supplied

Expression of inducible nitric oxide synthase in paired neoplastic and non-neoplastic primary prostate cell cultures and prostatectomy specimen.

Nitric oxide (NO) is an important signaling molecule for ischemia, inflammation, angiogenesis, immune response, and cell growth and differentiation. It has recently been shown that increased production of NO within various human cancers may contribute to tumor angiogenesis, tumor growth and metastasis, and tumor-related immune suppression. NO can be produced by several NO synthases (NOS), including inducible synthase (iNOS), which is expressed during cell activation and produces NO in larger quantity and for a longer period of time than non-inducible NOSs. In this study, we examined the expression levels of iNOS mRNA and protein in prostate adenocarcinoma using a paired nonneoplastic and neoplastic primary prostate cell culture system and related prostatectomy specimens. Six pairs of neoplastic and nonneoplastic primary prostate cell cultures were established from radical prostatectomy specimens based on homogeneity of the originating tumor and the nonneoplastic tissue. Radioactive reverse transcriptase polymerase chain reaction and subsequent quantitative analysis of iNOS mRNA were performed on the cultures using beta-actin as an internal control. Immunohistochemical studies with an anti-iNOS monoclonal antibody were performed on the corresponding formalin-fixed paraffin-embedded prostatectomy tissue sections. We observed marked patient-to-patient variation in "normal" levels of iNOS mRNA. However, all six neoplastic cultures showed moderately to markedly higher mRNA levels than did their paired nonneoplastic cultures. In addition, iNOS protein levels were significantly higher in paraffin-embedded prostate cancer tissue sections than in adjacent nonneoplastic tissue. Overexpression of iNOS mRNA and protein levels is present in moderately differentiated prostate adenocarcinoma and may contribute to prostate cancer angiogenesis, tumor growth, and tumor-related immunosuppression.

Adenocarcinoma↗