Masahiko Ohara

Kochi University, Kōchi-shi, Kochi-ken, Japan

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Publications (38)55.04 Total impact

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    ABSTRACT: H. Ohsaki, T. Hirouchi, N. Hayashi, E. Okanoue, M. Ohara, N. Kuroda, E. Hirakawa and Y. Norimatsu Diagnostic value of urine erythrocyte morphology in the detection of glomerular disease in SurePath™ liquid-based cytology compared with fresh urine sediment examination Objective:  To assess whether the morphology of urine erythrocytes can be an effective tool for distinguishing glomerular disease from lower urinary tract disease in SurePath(™) liquid-based cytology (SP-LBC). Methods:  We examined four morphological parameters of erythrocytes: (1) irregular erythrocytes (of all types including fragmented forms) comprising greater than or equal to 20% of erythrocytes; (2) uniform erythrocytes (>80%); (3) doughnut or target-like shaped (D/T) erythrocytes (≥1%); and (4) acanthocytes (≥1%) in glomerular disease (n = 32) and lower urinary tract disease (n = 20) with SP-LBC slides in cases that had also been assessed by fresh urine sediment examination. Results:  Sensitivity of D/T erythrocytes and acanthocytes (dysmorphic erythrocytes) for glomerular disease were 100% and 87.5%, respectively, with urine sediment examination, and 81.3% and 46.9%, respectively, in SP-LBC slides. Specificity was 100% for D/T erythrocytes and acanthocytes using either procedure. While irregular erythrocytes were specific for glomerular disease using urine sediment examination, they were seen in 70% of those with lower urinary tract disease using SP-LBC slides as a result of the deformation of erythrocytes by the fixative. Conclusions:  Although the sensitivity of D/T erythrocytes and acanthocytes for glomerular disease was lower in SP-LBC slides than fresh urine sediment examination, their specificity was equally high. Therefore, urine erythrocyte morphology is useful in the detection of glomerular disease with the SP-LBC slides. However, morphological features apart from D/T erythrocytes and acanthocytes are not useful in SP-LBC slides.
    Cytopathology 02/2012; · 1.71 Impact Factor
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    ABSTRACT: Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a rare tumor. Moreover, there are only three reports to date that have focused on the cytologic findings of cervical LCNEC. We report the case of a 59-year-old Japanese woman with cervical LCNEC combined with small cell carcinoma (SmCC). Cytologic specimens from the uterine cervix demonstrated large cells with coarse chromatin and prominent nucleoli. Frequent mitotic figures were also observed. Curettage of the uterine endometrium revealed an endometrioid adenocarcinoma with squamous differentiation; i.e., an adenoacanthoma. Histologic examination of surgically resected uterine cervical tissue revealed LCNEC with minor foci of SmCC. Neuroendocrine differentiation in LCNEC was confirmed by immunohistochemistry for synaptophysin and CD56. Cytotechnologists or pathologists need to consider a differential diagnosis of LCNEC while examining cervical cytologic specimens; therefore, it is important to correctly identify the cytologic characteristics of this tumor. Diagn. Cytopathol. 2011; © 2011 Wiley-Liss, Inc.
    Diagnostic Cytopathology 10/2011; · 1.49 Impact Factor
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    ABSTRACT: Translocation-type renal carcinoma has been recently discovered, and it is possible that this tumor may have been previously diagnosed as other types of renal tumor. We have subjected 41 renal tumors, including VHL gene mutation-negative clear cell renal cell carcinoma (RCC), papillary RCC, and chromophobe RCC, to immunohistochemistry of transcription factor E3 (TFE3) and TFEB. All tumors were histologically evaluated by additional immunohistochemical study. As a result, 5 tumors showed a positive reaction for TFE3 with a range from 1+ to 2+ in intensity. No tumors were positive for TFEB. In 5 tumors immunohistochemically positive for TFE3, chimeric transcripts including ASPL-TFE3, PRCC-TFE3, CLTCTFE3, PSF-TFE3, or Nono-TFE3 were not detected. The diagnosis of 6 tumors was changed by reevaluation through retrospective histological and immunohistochemical study. In 4 of 6 tumors, the diagnosis of clear cell RCC was changed to chromophobe RCC. In 1 tumor, oncocytoma was detectable, and RCC with rhabdoid features and sarcomatoid changes was detected in 1 tumor. Finally, the cutoff value of TFE3 immunohistochemistry should be more than 2+ with a wide range. The translocation-type renal carcinoma seems to be quite rare.
    Medical Molecular Morphology 03/2011; 44(1):46-51. · 1.17 Impact Factor
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    ABSTRACT: Hybrid sclerosing adenosis and basal cell hyperplasia of the prostate is a rare lesion. Here we report the seventh case of such lesions. Histological examination of the transurethral resection of the prostate of a 83-year-old Japanese man showed a small lesion consisted of sclerosing adenosis and basal cell hyperplasia, in addition to the diffuse glandular and fibromuscular hyperplasia. Immunohistochemically, many basal cells in sclerosing adenosis and basal cell hyperplasia areas showed a positive reaction for p63, cytokeratin 5, and D2-40. Additionally, many basal cells in the sclerosing adenosis area and some basal cells in the basal cell hyperplasia area were positive for S-100 protein and alpha-smooth muscle actin, which are myoepithelial cell markers. Finally, we suggest that hybrid sclerosing adenosis and basal cell hyperplasia may be actually a special form of hyperplastic lesion of all components of prostatic tissue, reflecting the unbalanced distribution of glandular, stromal (sclerosing adenosis), and basal cell hyperplasia with the differentiation toward myoepithelial cells predominantly occurring in a sclerosing adenosis area. Additionally, this case showed that D2-40 is a useful marker of basal cells.
    Medical Molecular Morphology 12/2010; 43(4):226-30. · 1.17 Impact Factor
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    ABSTRACT: Lymphoepithelioma-like carcinoma and adenosquamous carcinoma of the stomach are relatively rare tumors. To date, there are no reports on lymphoepithelioma-like carcinoma of the stomach associated with adenosquamous carcinoma. We report herein the first case of such a tumor. A 67-year-old Japanese man presented with dull epigastralgia. The gastric endoscopy revealed an ulcerative cancerous lesion of the upper portion. Histological examination of the gastric tumor showed the coexistence of lymphoepithelioma-like carcinoma and adenosquamous carcinoma. The former showed a positive reaction for Epstein-Barr virus-encoded RNA (EBER). Neoplastic cells of the latter were immunoreactive for p63 and keratin 903, and Alcian blue stain detected acid mucin in glandular lumens. This pattern resembled mucoepidermoid carcinoma in the salivary gland. Finally, this is the first case of gastric lymphoepithelioma-like carcinoma associated with adenosquamous carcinoma, and clinicians and pathologists should recognize the presence of such a tumor.
    Medical Molecular Morphology 09/2010; 43(3):170-3. · 1.17 Impact Factor
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    ABSTRACT: D2-40 has been recently discovered as a lymphatic endothelial cell marker, and some investigators have found that D2-40 is also expressed in myoepithelial cells of salivary gland or breast. In this study, we evaluated D2-40 expression of basal cells and applied D2-40 immunohistochemistry in the combination of P504S, cytokeratin 5, and p63 for ten lesions with atypical small acinar proliferation (ASAP) in initial prostatic needle biopsy. As a result, D2-40 was expressed in basal cells, lymphatic endothelial cells, and some stromal fibroblasts of normal prostatic tissue. Among ten ASAP lesions, the final diagnosis of seven lesions was resolved by combination immunohistochemistry. D2-40 was comparable to cytokeratin 5 and p63 as a basal cell marker, and there were no lesions that failed to provide an accurate final diagnosis using only D2-40 immunohistochemistry without cytokeratin 5 or p63. However, we found some D2-40-positive stromal fibroblasts or D2-40-positive lumen-collapsed lymphatic vessels neighboring atypical glands. Pathologists should pay attention to avoid recognizing these cells as basal cells. In conclusion, the combination of immunohistochemistry of P504S, cytokeratin 5, p63, and D2-40 may contribute to the accurate diagnosis of ASAP in the initial prostatic needle biopsy.
    Medical Molecular Morphology 09/2010; 43(3):165-9. · 1.17 Impact Factor
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    ABSTRACT: Renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusion recently has been found. In this article, we demonstrate an unusual features of such a case. A 73-year-old Japanese woman presented with macroscopic hematuria. The imaging examinations disclosed the renal tumor. Histological examination showed the finding of ASPL-TFE3 RCC, which was characterized by papillary, alveolar, or solid growth of voluminous cell with clear and eosinophilic cells, and stromal psammoma body and hyaline nodules. Additionally, shrunken nuclei, thick cell border, and perinuclear clearing characteristic of chromophobe renal cell carcinoma were observed in the alveolar growth area and the transitional zone between stromal hyalinization, and osseous metaplasia was identified. Immunohistochemically, nuclei of tumorous cell were diffusely positive for TFE3. A RT-PCR study revealed the ASPL-TFE3 chimeric transcript. Finally, pathologists should recognize that the histology of RCC associated with Xp11.2 translocation/TFE3 gene fusion may focally resemble that of chromophobe RCC, but TFE3 immunohistochemistry and molecular genetic study may be helpful in the differential diagnosis. Moreover, osseous metaplasia as well as psammoma bodies should be added to the histological spectrum of the stromal change in RCC associated with Xp11.2 translocations/TFE3 gene fusions.
    Medical Molecular Morphology 06/2010; 43(2):86-90. · 1.17 Impact Factor
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    ABSTRACT: Solid papillary carcinoma is a rare breast lesion, but this entity remains poorly recognized. In this article, we report a case of solid papillary carcinoma of the breast with focus on cytological and histological findings. A 66-year-old Japanese woman presented with nipple discharge. Imprint cytology obtained from the surgically resected breast specimens showed a plasmacytoid appearance and spindle cell morphology with low-grade atypia. Histologically, the tumor revealed findings of solid papillary carcinoma and predominantly showed an intraductal lesion with focal minimal invasion into the breast parenchyma. Fibrovascular cores with hyalinization were seen. Proliferation of short spindle cells was also focally observed. Pseudorosette formation or nuclear palisading at the stromal-glandular interface was seen, and intracellular or extracellular mucin deposition was occasionally identified. Nuclear atypia generally showed low grade. Finally, clinicians, cytotechnologists, and pathologists should recognize this rare tumor entity because this tumor is a malignant neoplasm showing characteristic pathological findings.
    Medical Molecular Morphology 03/2010; 43(1):48-52. · 1.17 Impact Factor
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    ABSTRACT: IgG4-related disease has been recently described. This disease occurs in various anatomic locations including pancreas, biliary tract, liver, retroperitoneum, kidney, breast, lung, thyroid gland, prostate, salivary gland, lacrimal gland, and lymph node. In this article, we report the first case of IgG4-related disease arising in the renal pelvis. A 49-year-old Japanese woman was found to show left hydronephrosis by a medical checkup. Histological examination of the renal pelvic tumor showed IgG4-related disease. Her postoperative serum IgG4 was elevated, and this was compatible with IgG4-related disease. Systemic examination showed swelling of major and minor salivary glands and the lacrimal glands, and biopsy of the minor salivary gland revealed the finding of IgG4-related disease. Finally, pathologists and clinicians should be aware of the possibility that the renal pelvis may be involved in IgG4-related systemic disease.
    Medical Molecular Morphology 12/2009; 42(4):236-8. · 1.17 Impact Factor
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    ABSTRACT: Pulmonary epithelioid angiosarcoma is rare, and there are no descriptions of the immunocytochemistry of such a case. We report a case with focus on immunocytochemistry of imprint cytological specimens here. A 43-year-old Japanese man presented with cough. Brushing cytology of the tumor using a bronchoscope showed a malignant neoplasm. Subsequently, left lower lobectomy was undertaken. Imprint cytological material of the neoplastic cells noted some clusters of round, or oval, to polygonal epithelioid cells. Histological examination showed the proliferation of epithelioid neoplastic cells containing erythrocytes in the cytoplasm. The immunocytochemistry in imprint cytological specimens showed a focal positive reaction for von Willebrand factor, and the immunohistochemistry of the surgically resected lung tumor showed a focal positive reaction for Fli-1, von Willebrand factor, CD31, and CD34. Finally, we suggest that the immunocytochemical study of imprint cytological materials may supply available information in diagnosing angiosarcoma with epithelioid features lacking characteristic structures.
    Medical Molecular Morphology 12/2009; 42(4):250-3. · 1.17 Impact Factor
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    ABSTRACT: Clear cell chondrosarcoma (CCC) is a rare neoplasm. We report here a case of CCC. A 67-year-old Japanese man presented with right arthralgia for 1 year, and histological examination of the subsequent surgical resection of the right femoral bone showed the finding of CCC. Ultrastructurally, most organelles were observed in the perinuclear area. Clear neoplastic cells contained many glycogen particles in the area of the cytoplasm lacking organelles, although glycogen particles overall seemed to be evenly distributed in the cytoplasm. Some mitochondria, Golgi complex, actin-like filaments, and rough endoplasmic reticulum were also demonstrated in the cytoplasm of clear cells. Well-developed microvilli were also seen on the surface of neoplastic cells. These structures in neoplastic cells corresponded notably to structures of normal chondrocytes. Finally, our ultrastructural findings support further evidence that clear cells in CCC may show chondrocyte differentiation and a lack of an organelles area as well as abundant glycogen particles, may contribute to the clear cell morphology in CCC.
    Medical Molecular Morphology 09/2009; 42(3):185-8. · 1.17 Impact Factor
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    ABSTRACT: Renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusion has been recently identified. Herein is presented a case of RCC with Xp11.2 translocations/TFE3 gene fusions with unusual histological findings. A 68-year-old Japanese woman was incidentally found to have a renal mass on CT. Histological examination showed clear cell neoplasm with alveolar and papillary growth patterns. The nuclear atypia corresponded to Fuhrman grade 3. Additionally, smooth muscle stroma was observed and abnormal vessels showing a heterogeniety in thickness were also identified. On immunohistochemistry, neoplastic cells were diffusely positive for transcription factor E3 (TFE3) and Melan A, and focally positive for CD10 and RCC marker. The smooth muscle stroma was positive for alpha-smooth muscle actin and h-caldesmon, but reverse transcription-polymerase chain reaction of the tumor using frozen material could not detect any previously reported chimeric transcripts including ASPL-TFE3, PRCC-TFE3, CLTC-TFE3, PSF-TFE3 or NoNo-TFE3. G-band karyotype was unsuccessful. Pathologists should pay attention to the afore-described unusual stromal reaction of adult-onset RCC associated with Xp11.2 translocations/TFE3 gene fusions.
    Pathology International 08/2009; 59(7):486-91. · 1.72 Impact Factor
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    ABSTRACT: Recently, the concept of basal-like carcinoma has been proposed. However, there are only a few reports about the relationship between triple-negative cancer and basal-like carcinoma. In this article, we report the study of the expression of basal cell markers in 11 triple-negative cancers. Eight tumors (4 metaplastic carcinomas, 2 invasive ductal carcinomas, 1 invasive papillary carcinoma, and 1 medullary carcinoma) were positive for more than three markers among cytokeratins 5, 14, and 17, and p63. Three tumors (2 invasive ductal carcinomas and 1 apocrine carcinoma) were completely negative for all markers. Among 8 tumors positive for basal markers, cytokeratins 5 and 17 were expressed in all 8 tumors, cytokeratin 14 in 6 tumors, and p63 in 7 tumors. Finally, we conclude that the majority of triple-negative cancer may correspond to basal-like carcinoma, but the two entities are not identical. The use of combination immunohistochemistry including cytokeratins 5, 14, and 17 and p63 may contribute to the detection of basal-like carcinoma.
    Medical Molecular Morphology 07/2009; 42(2):128-31. · 1.17 Impact Factor
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    ABSTRACT: Ureteral small cell carcinoma is very rare; only eight cases have been reported in the literature. In this article, we report the ninth case of ureteral small cell carcinoma. A 79-year-old Japanese man presented with asymptomatic macrohematuria, and left nephroureterectomy was performed. The nonpapillary and broad-based tumor, which measured 3.7 x 3.7 x 2.0 cm, was seen in the lower portion of the left ureter just above the ureteral orifice. Microscopically, the tumor was composed of urothelial carcinoma and small cell carcinoma. Immunohistochemically, neoplastic cells of small cell carcinoma were focally positive for chromogranin A. In the normal ureteral mucosa adjacent to the tumor, some endocrine cells positive for chromogranin A and synaptophysin were identified. In conclusion, we suggest that endocrine cells in the ureteral urothelial epithelium may be precursor cells of ureteral small cell carcinoma.
    Medical Molecular Morphology 04/2009; 42(1):55-7. · 1.17 Impact Factor
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    ABSTRACT: Adenomyoepitheliomas are rare breast tumors. We report an unusual case of adenomyoepithelioma associated with invasive ductal carcinoma here. Histologically, the lesion consisted of two separate tumors. One nodule corresponded to invasive ductal carcinoma consisting of tubular and trabecular arrangements of columnar or cuboidal neoplastic cells. The other tumor corresponded to adenomyoepithelioma consisting of an inner layer of neoplastic cells with basophilic cytoplasm and the outer layer of neoplastic cells with clear cytoplasm. Immunohistochemically, some myofibroblasts were observed in the stroma of both adenomyoepithelioma and invasive ductal carcinoma, but no CD34-positive stromal cells were seen in the stroma of either lesion. The stromal reaction of adenomyoepithelioma resembles that of intraductal papilloma in the previous study. To the best of our knowledge, this is the first case of coexistent adenomyoepithelioma and invasive ductal carcinoma of the breast that were discovered as separate nodules. Clinicians and pathologists should be aware of such an association because they need to distinguish such a case from malignant neoplasms arising in adenomyoepithelioma. Additionally, our preliminary report suggests that the stromal response of adenomyoepithelioma may resemble that of intraductal papilloma.
    Medical Molecular Morphology 01/2009; 41(4):238-42. · 1.17 Impact Factor
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    ABSTRACT: In this article, we report a rare case of hitherto undescribed acquired cystic disease (ACD)-associated renal cell carcinoma (RCC) with sarcomatoid change. A 78-year-old woman had been receiving hemodialysis for fourteen years at the time when a renal tumor was encountered on the follow-up examination of the kidney. Microscopically, oncocytic cuboidal cells proliferated with tubular, cribriform or papillary growth patterns, and atypical columnar cells with abundant cytoplasm proliferated with papillary configuration. Oxalate crystal deposition was observed in the stroma and the tumor focally resembled translocation type (TFE3) RCC. Sarcomatous neoplastic cells were also seen. The cytoplasm of oncocytic and sarcomatous neoplastic cells was diffusely positive for anti-mitochondrial antibody and the ultrastructural examination detected many mitochondria in the cytoplasm of oncocytic carcinoma cells and sarcomatous neoplastic cells. The loss of chromosomes 1p, 2q11-22, 9 and 14 was observed using comparative genomic hybridization analysis. We thus report here a case of hitherto undescribed ACD-associated RCC intermingled with oncocytic cells, translocation type RCC-like area and sarcomatoid change. This is the sixth case of sarcomatoid RCC arising in end-stage kidney disease.
    Histology and histopathology 12/2008; 23(11):1327-31. · 2.28 Impact Factor
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    ABSTRACT: Elastofibroma is a rare neoplasm. In this article, we report our study of the pathogenesis of fibrosis in elastofibroma. Three tumors obtained from two patients were selected. One patient was a 57-year-old Japanese woman who had a bilateral tumor, and the other patient was a 83-year-old Japanese man. All tumors occurred in the infrascapular region. Macroscopically, the cut surface of all tumors showed a poorly defined and whitish mass with yellowish foci. Microscopically, the tumor consisted of collagen fiber bundles, abnormal elastic fibers, and spindle cells suggestive of fibroblasts. Elastica-van Gieson and Masson-trichrome stain identified abnormal elastic fibers and abundant collagen fibers, respectively, in elastofibroma. Immunohistochemically, fibroblasts were positive for CD34 but negative for alpha-smooth muscle actin and h-caldesmon. Additionally, the cytoplasm of many fibroblasts was positive for TGF-beta in all tumors. Ultrastructurally, some fibroblasts with abundant organelles in one tumor were observed in the adjacent area to amorphous elastic mass and bundles of collagen fibers. However, no myofibroblasts were ultrastructurally identified in the tumor. Finally, our study supplies further evidence that elastofibroma may show the proliferation of CD34-positive fibroblasts and contain no myofibroblasts, and that fibroblasts may produce both abnormal elastic fibers and collagen fibers through the secretion of TGF-beta.
    Medical Molecular Morphology 10/2008; 41(3):179-82. · 1.17 Impact Factor
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    ABSTRACT: Some investigators have previously suggested that basal-like carcinoma may consist of components of invasive ductal carcinoma, not otherwise specified, metaplastic carcinoma, and medullary carcinoma. We report here two cases of breast carcinoma showing basal cell/myoepithelial differentiation. The first case was a 58-year-old Japanese woman and the second case was a 39-year-old Japanese woman. The two tumors were composed of the proliferation of epithelial cells and/or spindle-or stellate-shaped cells on the background of mucinous materials. Additionally, chondroid matrix was observed in the metastatic lesion of the first case and the primary lesion of the second case. Immunohistochemically, epithelial neoplastic cells were positive for E-cadherin and cytokeratin CAM5.2, and epithelial and spindle-or stellate-shaped cells were positive for cytokeratins 5, 14, or 17, alpha-smooth muscle actin, S-100, and p63. Our results supply further evidence that most metaplastic carcinomas may be actually be basallike carcinomas.
    Medical Molecular Morphology 07/2008; 41(2):117-20. · 1.17 Impact Factor
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    ABSTRACT: We incidentally found the expression of D2-40 in Cajal interstitial cells for the immunohistochemical valuation of lymphatic invasion by gastric and colonic cancer cells. Therefore, we suggested that D2-40 might become an available marker for gastrointestinal stromal tumors (GISTs). In this study, we performed immunohistochemical study of 21 GISTs, As a result, we confirmed a positive reaction for D2-40 in sixteen GISTs. Among sixteen tumors, thirteen tumors were focally positive and remaining three tumors were diffusely positive. We could find no relationship between positive findings for D2-40 and size or location of the tumor. Three of four tumors with intermediate risk of aggressive behavior and two of four tumors with recurrence showed a negative reaction for D2-40. In conclusion, we suggest that D2-40 may be an available marker of GISTs, but the expression of D2-40 seems to be not associated with the degree of risk of aggressive behavior.
    Medical Molecular Morphology 07/2008; 41(2):109-12. · 1.17 Impact Factor
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    ABSTRACT: Sustentacular and dendritic cells are known as the stromal components of extraadrenal paraganglioma. We identified a third stromal component in such a case. A 66-year-old Japanese woman complained of abdominal pain. The tumor was discovered near the right adrenal gland in the retroperitoneum. Histologically, the tumor consisting of round to oval neoplastic cells with eosinophilic cytoplasm proliferating with a "zellballen" pattern. Sustentacular cells were positive for S-100. Dendritic cells positive for HLA-DR were seen among the neoplastic nests. Additionally, many alpha-smooth muscle actin (ASMA)-positive and hcaldesmon-negative stromal cells, namely, myofibroblasts, were distributed in the capsule and fibrous band. Ultrastructurally, myofibroblasts contained many myofilaments and dense bodies in the cytoplasm. Finally, we identified the third stromal component, namely, myofibroblasts, in the extraadrenal paraganglioma. These myofibroblasts may play a role in the stromal response of host against neoplasm or the regulation of tumor growth.
    Medical Molecular Morphology 04/2008; 41(1):59-61. · 1.17 Impact Factor