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Masazumi Tsuneyoshi

Publications and source records attributed to Masazumi Tsuneyoshi.

At least 91 records · Page 5Linked to original sources
PubMed2004

The role of nuclear Y-box binding protein 1 as a global marker in drug resistance.

Gene expression can be regulated by nuclear factors at the transcriptional level. Many such factors regulate MDR1 gene expression, but what are the sequence elements and transcription factors that control the basal and inducible expression of this gene? The general principles through which transcription factors participate in drug resistance are now beginning to be understood. Here, we review the factors involved in the transcriptional regulation of the MDR1 gene. In particular, we focus on the transcription factor Y-box binding protein 1 and discuss the possible links between Y-box binding protein 1 expression and drug resistance in cancer, which are mediated by the transmembrane P-glycoprotein or non-P-glycoprotein.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2003

Blockade of constitutively activated Janus kinase/signal transducer and activator of transcription-3 pathway inhibits growth of human pancreatic cancer.

Constitutive activation of signal transducer and activator of transcription (Stat) proteins has been demonstrated in a wide variety of malignancies. In this study, we elucidated the significance of Janus kinase (JAK) and the downstream transcription factor Stat3 signals on malignant potentials of pancreatic cancer. Electrophoretic mobility shift assay and immunohistochemical analysis revealed that Stat3 was constitutively activated in subsets of human pancreatic cancer tissues and cell lines (Panc1, Kp4, AsPC-1, BxPC-3). A JAK-specific inhibitor, tyrphostin AG490, markedly inhibited Stat3 activation and expression of cyclin D1, bcl-xL and vascular endothelial growth factor mRNAs estimated by RT-PCR, as followed by growth arrest (6.3-21.3% vs controls; P<0.001) of pancreatic cancer cells. Inactivation of Stat3 by dominant-negative Stat3 adenovirus partly suppressed the growth of pancreatic cancer cells on day 4 post-inoculation (P<0.05) but not the expression of these mRNAs. These results indicate that activation of the JAK/Stat3 signaling pathway plays an important role in the progression of pancreatic cancer and that blockade of JAK/Stat3 signals may provide a novel therapeutic strategy for pancreatic cancer.

Cell Division↗
PubMed2003

Skull base and nonskull base chordomas: clinicopathologic and immunohistochemical study with special reference to nuclear pleomorphism and proliferative ability.

BACKGROUND: To the authors' knowledge, little is known regarding the relation between the proliferative ability and clinicopathologic parameters in skull base chordomas (SBCs) and nonskull base chordomas (NSBCs). METHODS: The authors investigated 122 conventional chordomas for their clinicopathologic parameters, proliferative ability (MIB-1 labeling index [LI]) and clinical outcome. RESULTS: Primary NSBCs were found to affect more elderly patients and demonstrated a higher MIB-1 LI compared with primary SBCs. Mitosis was more commonly noted in recurrent NSBCs compared with primary NSBCs. Apoptosis was more frequent in elderly patients than in younger patients with regard to both SBCs and NSBCs. Apoptosis also was found to be correlated with necrosis in SBCs, suggesting a common factor for the two different types of cell death. Mucoid matrix was reported to be more abundant in NSBCs than in SBCs, and appeared to occur more often in elder NSBC patients compared with younger NSBC patients. This indicates that it is produced in the later stages of tumorigenesis. In SBCs, several clinicopathologic parameters were found to be correlated with MIB-1 LI. Among them, increased age, recurrence, and nuclear pleomorphism were the only independent factors found to indicate a higher MIB-1 LI. No such parameters were found in NSBCs. However, in these lesions, prognosis was significantly poorer in those cases with nuclear pleomorphism compared with those without. CONCLUSIONS: The results of the current study suggest that nuclear pleomorphism is a prognostic indicator in NSBCs. The proliferative ability of SBCs appears to be closely associated with patient age, clinical status (recurrence), and nuclear pleomorphism.

Adolescent↗
PubMed2003

Newly established Askin tumor cell line and overexpression of focal adhesion kinase in Ewing sarcoma family of tumors cell lines.

Askin tumor is a malignant small round cell tumor that originates from the thoracopulmonary region and is a member of Ewing sarcoma family of tumors (ESFT). Only a few Askin tumor cell lines have been established. An Askin tumor cell line, designated MP-ASKIN-SA, was established from the left thoracic tumor of a 13-year-old Japanese boy. ESFT is known to have a high rate of distant metastases at diagnosis. The genes controlling the spread of ESFT cells, however, have not been elucidated. G-banding chromosome analysis revealed that the MP-ASKIN-SA cell line has complex chromosomal abnormalities including trisomy 8. The EWS/FLI1 chimeric transcript and c-myc overexpression were revealed by the reverse transcriptase-polymerase chain reaction and Northern blot analysis. Furthermore, we investigated the expression of the focal adhesion kinase (FAK) gene in the ESFT cell lines using Northern blot analysis. In addition to the MP-ASKIN-SA cell line, six Ewing sarcoma cell lines, one peripheral nerve sheath tumor cell line, and two Askin tumor cell lines were analyzed. All ESFT cell lines, including MP-ASKIN-SA, expressed five- to twenty-eight-fold-increased values of FAK, as compared with fibroblasts obtained from the bone marrow of a healthy volunteer. These results raise the possibility that the overexpression of c-myc and FAK are involved in the poor prognosis of ESFT.

Adolescent↗
PubMed2003

Downregulation of Cap43 gene by von Hippel-Lindau tumor suppressor protein in human renal cancer cells.

We previously identified 9 genes (i.e., thymosin beta4, secreted protein acidic and rich in cysteine, Cap43, ceruloplasmin, serum amyloid A, heat shock protein 90, LOT1, osteopontin and casein kinase Igamma) that are more highly expressed in cancerous regions than in noncancerous regions in human renal cancers. In our study, we considered the possibility that the von Hippel-Lindau (VHL) tumor suppressor gene might be able to affect the expression of these 9 genes in renal cancer cells. We first established 2 VHL-positive cell lines, 786/VHL-1 and 786/VHL-2, after the introduction of wild-type VHL into VHL-negative renal cancer 786-O cells. Of these 9 genes, expression of the Cap43 gene was specifically downregulated by VHL. Expression of Cap43 was also much lower in 4 other VHL-positive renal cancer cell lines than in VHL-negative 786-O cells. Cap43 promoter assays with several deletion or mutation constructs demonstrated that the Sp1 site in the element from -286 base pairs (bp) to -62 bp was partly responsible for VHL-induced suppression of the Cap43 gene. Immunostaining analysis with human specimens of renal cancers demonstrated that the Cap43 protein was expressed in most cancer cells and macrophages. We also observed a marked and specific increase of Cap43 mRNA levels in response to hypoxia or nickel in all VHL-positive cell lines. Cellular expression of Cap43 mRNA in response to hypoxia or nickel thus is closely associated with VHL gene expression in renal cancer cells. Although the function of the Cap43 protein remains unclear, the expression of Cap43 protein could be a molecular marker closely associated with VHL in renal cancer.

Carcinoma, Renal Cell↗
PubMed2003

Primary gastrointestinal lymphoma in Japan: a clinicopathologic analysis of 455 patients with special reference to its time trends.

BACKGROUND: An optimal treatment modality for patients with primary gastrointestinal lymphoma has not yet been established. This study aimed to elucidate the clinicopathologic features of this disease and the influence of therapeutic modalities on the prognosis in Japanese patients METHODS: The clinicopathologic features of 455 patients with primary gastrointestinal lymphoma were investigated retrospectively regarding treatment modalities and time trends. RESULTS: This study comprised 342 patients (75%) with gastric lymphoma, 96 patients (22%) with intestinal lymphoma, and 17 patients (4%) with both gastric and intestinal lymphoma. Two hundred thirty-one (51%) patients were classified as having low-grade B-cell lymphoma including 200 marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) type, 185 (41%) patients were classified as having high-grade B-cell lymphoma including 76 diffuse large cell lymphoma plus MALT lymphoma, and 39 (9%) patients were classified as having T-cell lymphoma. The frequency of nonsurgical treatment, including Helicobacter pylori eradication, chemotherapy, and radiation, increased during the latest decade. Patients who received nonsurgical treatment showed a better overall survival than those treated by surgery, but event-free survival did not differ between two groups. Cox multivariate analysis revealed that early stage, younger age, gastric localization, B-cell phenotype, and absence of B symptoms were independent prognostic factors for better overall and event-free survivals. Mucosa-associated lymphoid tissue-derived lymphoma was also an independent prognostic factor for event-free survival, but not for overall survival. CONCLUSIONS: Nonsurgical treatment may be an optimal therapeutic modality for patients with primary gastrointestinal lymphoma.

Adolescent↗
PubMed2003

The role of P-glycoprotein in intestinal tumorigenesis: disruption of mdr1a suppresses polyp formation in Apc(Min/+) mice.

P-glycoprotein (P-gp) mediates the active transport of various substrates including xenobiotics, and it thus has a protective function in various cell types and tissues/organs including the intestinal epithelium. However, whether or not P-gp plays a positive role in the intestinal tumorigenesis is unclear. We have introduced disrupted alleles of the murine P-gp gene, mdr1a, into Apc(Min/+) mice to evaluate whether P-gp plays any role in intestinal carcinogenesis. Spontaneously occurring DNA damage was significantly increased in both the small and large intestine of mdr1a(-/-), Apc(Min/+) mice compared with mdr1a(+/+), Apc(Min/+) mice. Furthermore, we observed active proliferation and rapid migration/disappearance of enterocytes in the intestine of the compound mice deficient in mdr1a. Finally, we found that the number of polyps and cancers was markedly decreased in mdr1a(-/-), Apc(Min/+) mice (P=0.0016). P-gp thus appears to play a positive role during intestinal tumorigenesis.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed2003

PTEN/MMAC1 gene mutation is a rare event in soft tissue sarcomas without specific balanced translocations.

The tumor suppressor gene PTEN/MMAC1 was identified on chromosome 10q23.3, which is homozygously deleted in many human malignancies. The loss of chromosome 10q was also frequently reported in some types of soft tissue sarcomas. Our study was designed to investigate the frequency of PTEN/MMAC1 gene mutation and to evaluate the role of the PTEN/MMAC1 gene in the tumorigenesis of soft tissue sarcomas without specific balanced translocations. We analyzed 51 cases of soft tissue sarcomas without specific balanced translocations for PTEN/MMAC1 mutations by polymerase chain reaction-single strand conformation polymorphism and direct sequencing. Mutations in the PTEN/MMAC1 gene were found in only 2 cases (3.9%). Both tumors with PTEN/MMAC1 mutation were leiomyosarcomas arising from the retroperitoneum and inferior vena cava, respectively. Two of 3 leiomyosarcomas arising from the intra-abdominal cavity examined harbored mutations of this tumor suppressor gene. This result suggests that leiomyosarcomas derived from the intra-abdominal cavity might have different tumorigenesis from those of an extremity or the trunk, from the viewpoint of PTEN/MMAC1 mutation, although PTEN/MMAC1 gene mutations are rare event in these soft tissue sarcomas.

Base Sequence↗
PubMed2003

Nuclear expression of Y-box-binding protein-1 correlates with P-glycoprotein and topoisomerase II alpha expression, and with poor prognosis in synovial sarcoma.

Nuclear expression of the Y-box-binding protein (YB-1) has been reported to correlate with the expression of P-glycoprotein in breast cancer and osteosarcoma. Overexpression of the ATP-binding cassette (ABC) superfamily, such as P-glycoprotein/multi-drug resistance (MDR) 1 and MDR-associated protein (MRP) 1, 2 and 3, has been reported in various malignant neoplasms. Fifty-four surgically resected synovial sarcomas were examined immunohistochemically for nuclear expression of YB-1 and intrinsic expression of P-glycoprotein, MRP1, MRP2, and topoisomerase II alpha, and the findings were compared with clinicopathological parameters, proliferative activities as evaluated by MIB-1 labelling index (LI), and the patients' prognoses. In addition, MDR1, MRP1, MRP2, and MRP3 mRNA levels were assessed using a quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method in 22 concordant frozen specimens from these cases and the findings were compared with six control skeletal muscle tissues. Independent prognostic factors were investigated using the Cox proportional hazards regression model. Nuclear expression of YB-1 protein correlated with P-glycoprotein expression (p = 0.0126). Moreover, cases with nuclear expression of YB-1 correlated with poor survival (p = 0.0495) and showed a high topoisomerase II alpha labelling index (topo II alpha LI) (p = 0.0056) and a high MIB-1 LI (p = 0.01). Multivariate Cox analysis showed that only the nuclear expression of YB-1 (p = 0.0136) and high American Joint Committee on Cancer (AJCC) stage (ie stage III or IV) (p < 0.0001) were independent factors for poor prognosis, while the expression of the YB-1 responsive gene products examined was not. These results indicate that the nuclear expression of YB-1 protein is associated with P-glycoprotein expression and proliferative activity as shown by the topo II alpha LI and the MIB-1 LI, and that expression of this protein is an important independent prognostic factor in synovial sarcoma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2003

Mechanisms of inactivation of the p16INK4a gene in leiomyosarcoma of soft tissue: decreased p16 expression correlates with promoter methylation and poor prognosis.

The p16INK4a tumour suppressor gene, encoding p16 protein, plays a crucial role in regulation of the G1 cell-cycle phase. To investigate the potential role of p16 in soft tissue leiomyosarcoma (LMS), an immunohistochemical analysis was performed of 77 LMSs for p16 expression. Decreased expression of the p16 protein was identified in 25 of 77 LMSs (32%). Decreased expression of p16 correlated significantly with large tumour size (p=0.0038). In a univariate analysis, large tumour size and decreased expression of p16 were statistically significant adverse prognostic factors (p=0.025 and p=0.0021, respectively). In a multivariate analysis including conventional clinicopathological parameters, decreased expression of p16 protein was revealed as the only independent unfavourable prognostic factor (p=0.012). To elucidate the mechanisms of inactivation of the p16INK4a gene, 49 LMSs for which genomic DNA was available were examined; analysis for homozygous deletion, mutation, and promoter hypermethylation was conducted using differential PCR, PCR-SSCP, and methylation-specific PCR, respectively. Promoter hypermethylation was detected in 11 of 49 LMS cases (22%); homozygous deletion was detected in 3 of 49 cases (6%); and mutation was not recognized in any of the cases studied. Eight of 15 cases (53%) with decreased expression of p16 protein revealed methylation of the p16INK4a gene promoter. Promoter hypermethylation correlated closely with decreased expression and poor prognosis (p=0.0014 and p=0.0088, respectively). These results suggest that decreased expression of p16 protein can be considered as an independent reliable prognostic parameter in patients with soft tissue LMS. Furthermore, promoter methylation was more frequent than either homozygous deletion or mutation in this tumour, and promoter methylation was also shown to have a strong association with inactivation of the p16INK4a gene.

Adolescent↗
PubMed2003

Intestinal phenotypic expression of gastric depressed adenomas and the surrounding mucosa.

BACKGROUND: Gastric depressed adenomas (DAs) have been reported to be more aggressive than nondepressed ones. To clarify any differences among them, we investigated the intestinal phenotypic expression of DAs and the surrounding mucosa. METHODS: Fifty DAs resected surgically or endoscopically were studied. Forty-two nondepressed adenomas (Non-DAs) were selected as controls. According to the classification of intestinal metaplasia, the phenotypes of the adenomas and surrounding mucosa were classified into four categories: complete intestinal type (I/Com-type), incomplete intestinal type (I/In-type), gastric type (G-type), and unclassified type (U-type), based on a combination of the expression of the antibodies CD10 (small-intestinal brush border), MUC2 (intestinal goblet cells) and HGM (gastric foveolar epithelium). RESULTS: I/In-type adenomas were frequently observed among DAs (60%), whereas I/Com-type adenomas were frequently seen in Non-DAs (52%). The incidence of phenotypes was significantly different among DAs and Non-DAs. Intestinal metaplasia was present in the surrounding mucosa of more than 90% of both DAs and Non-DAs. Surrounding mucosa of I/In-type was also frequently observed in DAs, as was that of I/Com-type in Non-DAs. The expression of p53 in DAs (8%) was higher than that in Non-DAs (5%). p53-positive adenomas were present only among the I/Com-type and I/In-type adenomas, while G-type and U-type adenomas showed no p53 positivity. CONCLUSIONS: Both DAs and their surrounding mucosa appear to have an unstable status, because they possess a hybrid phenotype of I/In-type more commonly than Non-DAs. Such instability could be considered a risk factor for neoplastic potential and, therefore, DAs should be followed carefully.

Adenoma↗
PubMed2003

Possible association between tumor-suppressor gene mutations and hMSH2/hMLH1 inactivation in alveolar soft part sarcoma.

Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor of unknown origin and pathogenesis. We clinicopathologically analyzed 16 cases of ASPS and screened for the genetic alterations of various tumor-suppressor genes and oncogenes, including p53, adenomatous polyposis coli (APC), E-cadherin, and beta-catenin, in 11 cases of ASPS. We also examined the expression of hMSH2/hMLH1 of DNA mismatch repair genes by immunohistochemistry, and promoter hypermethylation of these DNA mismatch repair genes by methylation-specific polymerase chain reaction (MS-PCR) to elucidate any possible association between mutation status of these genes and inactivation of the hMSH2/hMLH1 genes. Furthermore, microsatellite instability (MSI) analysis and loss of heterozygosity (LOH) on chromosome 5q analysis were used for some cases of ASPS where DNA derived from normal tissue was available. The 5-year overall survival rate for all of the patients in this study was 68.6%. The 5-year overall survival rates for patients presenting with localized ASPS and for patients with distant metastases were 83.3% and 47.6%, respectively. The high nuclear grade of tumor cells was a significantly adverse prognostic factor (P = 0.0085). Single-strand conformation polymorphism analysis followed by DNA direct sequencing revealed 4 point mutations of the p53 gene in 3 of 11 cases (27.3%), composed of 3 missense mutations and 1 silent mutation. In addition, 1 case with the E-cadherin missense mutation and 1 case with the APC missense mutations were observed, respectively. None of the cases harbored mutation of exon 3 of the beta-catenin gene. Loss of expression of the hMSH2 and hMLH1 genes was observed in 2 (18.2%) and 3 (27.3%) of 11 cases, respectively. All 3 cases with loss of hMLH1 gene expression harbored mutations of the p53 gene. There was a statistically significant correlation between the genetic alteration positive in these tumor-suppressor genes and loss of hMLH1 gene expression (P = 0.024). Methylation-specific PCR did not reveal hypermethylation of the hMSH2/hMLH1 promoter region in any of the cases examined. Three of 8 (37.5%) ASPS cases showed low MSI, and 2 of these 3 cases showed immunohistochemical lack of expression for either hMSH2 or hMLH1. LOH on 5q was present in 2 of 6 (33.3%) informative cases, and both cases showed LOH on the D5S346 marker, a microsatellite marker near the APC locus. Thus, inactivation of hMSH2/hMLH1 of DNA mismatch repair genes seems to have an important role to play in the mutagenesis of the tumor-suppressor genes in ASPS.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Prenatally diagnosed cystic neuroblastoma: a report of two cases.

We report two cases of prenatally diagnosed cystic neuroblastoma (PDCN). In the first case, prenatal ultrasonography (US) at 33 weeks' gestation showed a 30 x 20 mm cyst at the upper pole of the right kidney. The size and content of the mass demonstrated no change during pregnancy. Postnatal US showed no change in the cystic mass 4 weeks after birth compared to the prenatal findings. The infant underwent total resection of the tumour at 28 days of age. In the second case, a left cystic mass measuring 50 x 40 mm was detected in a fetus in the 37th week of pregnancy. Postnatal US showed a cystic mass in the left adrenal gland. The US findings showed no change 18 days after birth and the infant underwent total resection of the tumour at 19 days of age. In both cases, pathological examination revealed a neuroblastoma and all of the biological prognostic factors were favourable. Surgical intervention was necessary for a final histological and biological diagnosis to be made. We recommend that prenatally suspected neuroblastomas should normally undergo surgical intervention, unless tumour size decreases within about 1 month after birth.

Adrenal Gland Neoplasms↗
PubMed2003

Adrenal cytomegaly: two cases detected by prenatal diagnosis.

We report our experience with two cases of adrenal cytomegaly, both of which were detected as cystic adrenal masses during prenatal ultrasonographic examinations. In Case 1, a left suprarenal cystic mass was detected in the fetus at 25 weeks of gestation. The mass, measuring 7 cm in diameter, did not show any change in size and was resected 26 days after birth. In Case 2, a right suprarenal lesion was found at 30 weeks of gestation. The cystic lesion, measuring 2 cm x 1.5 cm, did not change in size and was resected 3 months after birth. Adrenal cytomegaly is still not well known. It is characterized by the presence of large polyhedral cells with eosinophilic granular cytoplasm and enlarged nuclei in the adrenal cortex. This condition is thought to be a degenerative process but not a malignancy. Adrenal cytomegaly rarely forms cysts. It seemed to be impossible to diagnose preoperatively in our cases. Because of the difficulty of differentiating between cystic adrenal cytomegaly and other cystic diseases such as neuroblastoma, operative intervention is required in cases where the cysts do not decrease in size. Further study of a larger number of cases is needed to establish an optimal treatment protocol for these tumours.

Adrenal Gland Diseases↗
PubMed2003

Sarcomatous hepatocellular carcinoma: a special reference to ordinary hepatocellular carcinoma.

BACKGROUND: Sarcomatous hepatocellular carcinoma (HCC) has a worse prognosis than ordinary HCC. The relationship between the malignant potential of sarcomatous HCC and cell proliferation or cell adhesion is unknown. This study was undertaken to clarify this relationship. METHODS: In 21 cases of sarcomatous HCC, including 16 surgically resected and five autopsy cases, immunohistochemistry was used to compare the sarcomatous component (s-comp) and the ordinary component (o-comp) within each sarcomatous HCC. RESULTS: We found 15 epithelial-cadherin (E-cadherin)-positive cases in o-comp (79%) and nine positive cases in s-comp (43%). The difference between sarcomatous HCC and ordinary HCC in E-cadherin-positive tumor prevalence was significant (P < 0.05). The Ki-67 (MIB1) labeling index ratio was 127 +/- 40 in s-comp and 80 +/- 33 in o-comp, and there was a greater tendency to have an ability to multiply in s-comp than in o-comp (P = 0.096). CONCLUSION: This study indicated that the loss of E-cadherin related to a morphological alteration in sarcomatous HCC; however, no relationship in respect to the malignant potential was found.

Adult↗
PubMed2003

Mixed tumor of deep soft tissue.

Mixed tumors of the salivary gland and skin are relatively common but are quite rare in soft tissue. It is believed that, as in the salivary gland form, most of these lesions are benign, but that a small subset behave in an aggressive fashion. We report here a patient with recurrent mixed tumor of soft tissue with infiltrative growth. The primary tumor arose in deep subfascial soft tissue of the right lower leg and was adjacent to the surface of the fibula. An open biopsy and complete resection were performed. Upon histological examination of the resected specimen, neoplastic cell infiltration at the tumor/soft tissue interface was not obvious; local recurrence, however, was observed 1 year later. The patient was treated with wide resection. Histological examination confirmed that the recurrent tumor with an extensive chondroid area invaded the osseous tissue of the fibula. At present, 1 year after the second resection surgery, there is no evidence of disease.

Adenoma, Pleomorphic↗
PubMed2003

Low-grade fibrosarcoma of the proximal humerus.

We present the clinical, radiographical and pathological features of low-grade fibrosarcoma of the left proximal humerus in a 23-year-old man in whom it was necessary to distinguish the tumor from desmoplastic fibroma, malignant fibrous histiocytoma and intramedullary well-differentiated osteosarcoma. The patient presented with a 10-day history of pain in his left upper arm sustained when trying to break his fall with his left hand when slipping in the street. Plain radiography revealed an expanding multilobular osteolytic lesion from the proximal metaphysis to the diaphysis of his left humerus, accompanied by a pathological fracture at the distal portion of the lesion. Open biopsy of the lesion was performed twice; however, a conclusive diagnosis could not be obtained. The patient underwent wide excision and prosthetic replacement of the left proximal humerus. Histologically, the resected tumor was composed of both cellular areas and hypocellular areas. Cellular areas revealed a proliferation of bundles of uniform fibroblastic spindle-shaped cells with minimal cellular atypia, mixed with abundant intercellular collagenization. Mitotic figures were occasionally seen. Hypocellular areas showed myxoid features with loose bundles of collagen fibers. The patient demonstrates no evidence of disease 42 months after surgery. It is important to detect the scant atypical cells for the differential diagnosis of low-grade fibrosarcoma and desmoplastic fibroma of bone.

Adult↗