Myxoid Type Research Articles

Oral Focal Mucinosis of the Tongue: A Rare Clinical Case

Oral focal mucinosis (OFM) is a rare mucosal lesion of unknown etiopathogenesis. It is considered the oral counterpart of cutaneous focal mucinosis. From the anatomo-pathological point of view it is characterised by a focal degeneration of myxoid type of connective tissue. A literature survey revealed 50 reports of OFM cases worldwide. Here, we present an even more rare case with tongue involvement. Particular emphasis is placed on diagnostic-differential aspects of this kind of lesion, both from the clinical and the histopathological point of view, in respect to other manifestations of tongue mucosa.

Myxoid chondrosarcoma of the cricoid cartilage

Primary cartilaginous bone tumors of the laryngeal region are extremely rare. Laryngeal chondrosarcomas account for 0.07–2% of all laryngeal neoplasms and less than 1% of all sarcomas.A 95% of all laryngeal chondrosarcomas are low-grade and are often underdiagnosed as benign chondromata. Biopsy is the cornerstone of the diagnosis. For definitive treatment there is a general consensus that conservative surgery is the most appropriate method. These tumors are known for their indolent course, low metastatic potential and high percentage of recurrence. The clinical outcome was the worse for patients with myxoid type of tumors, regardless of tumor grade or applied form of therapy. A 65-year-old man with no family history of malignant or hereditary diseases and a 50-year history of smoking 20 cigarettes a day presented with a 7-month history of breathy dysphonia.

Abstract A17: Mode of action of trabectedin in myxoid liposarcomas.

Abstract Background: Trabectedin (ET-743, Yondelis) is a marine alkaloid isolated from the tunicate Ecteinascidia turbinata, cytotoxic against a variety of tumor cell lines in vitro and human tumor xenografts in vivo. It has been approved by EMEA for the 2nd line therapy of soft tissue sarcomas in 2007 and for the 2nd line therapy of ovarian cancer in 2009. Myxoid liposarcoma (MLS) is a specific histological subtype within the family of adults soft tissue sarcomas. Specifically >90% of usual myxoid/round cell liposarcomas (MLS/RCLS) are characterized by the chromosomal translocation t(12;16) (q13;p11), which produces the FUS-CHOP oncogene. Different variants of the fusion gene have been previously described but with no demonstrable prognostic effect although the type III MLS seem correlate with a more severe outcome than type II MLS. Materials and Methods: To elucidate the mechanisms behind the differential sensitivity to trabectedin, myxoid liposarcomas type II and type III were xenografted in nude mice. When tumor load achieves about 200–400 mg mice were divided into the experimental groups. Trabectedin was administered at 0.15 mg/kg, i.v. every 7 days for three times. Tumor growth was monitored by Vernier caliper. The binding of FUS-CHOP to some of its target promoters was monitored by Chromatin Immuno Precipitation (ChIP) to verify the drug ability to displace the binding. ChIP were performed with ProtG Sepharose and the anti-FUS and anti-CHOP antibody. The immunoprecipitated DNAs were analyzed by quantitative Real Time PCR. FN1, PTX3, CDK4, IL8 and CHOP were used as target genes. Results: We found that trabectedin was more effective on type II than type III MLS xenografts. The response to trabectedin in type II xenografts was associated with partial regression and pathological response. Type III MLS xenografts appeared much less sensitive to trabectedin and tumors did not regress. Molecular analysis revealed that trabectedin was able to remove FUS-CHOP type II and III from its own target genes 24 hours after treatment. 72 hours after treatment, FUS-CHOP Type III was attached to its targets whereas FUS-CHOP Type II remained unbound. These data explain why in order to achieve a significant regression of type III MLS xenografts a more prolonged treatment with trabectedin is required. Conclusions: These results suggest that the different sensitivity of type II and type III MLS to trabectedin are related to a different duration of the drug ability to display FUS-CHOP from the selected target genes. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A17.

Dermatofibrosarcoma protuberans mixoide infantil

Dermatofibrosarcoma protuberans is a locally aggressive skin tumor that affects young and middle-aged adults. A number of histological variants have been described, the myxoid type being one of the least common. Microscopically it is formed of a neoplastic growth that is located in the dermis and hypodermis and has a predominant myxoid component. Peripherally there are infiltrating bundles of spindle-shaped cells that are diffusely positive for the CD34 immunohistochemical marker. We report a case of myxoid dermatofibrosarcoma protuberans on a finger of the left hand of a 14-year-old girl. The tumor had been present for at least 10 years. This is the first pediatric case of myxoid dermatofibrosarcoma protuberans at this site. This histological subtype has mainly been described on the extremities in adults and is very rare in children. We discuss the differential diagnosis with other CD34+ myxoid mesenchymal tumors.

High-level expression of podoplanin in benign and malignant soft tissue tumors: Immunohistochemical and quantitative real-time RT-PCR analysis

Podoplanin is a 38 kDa mucin-type transmembrane glycoprotein that was first identified in rat glomerular epithelial cells (podocytes). It is expressed in normal lymphatic endothelium, but is absent from vascular endothelial cells. D2-40 is a commercially available mouse monoclonal antibody which binds to an epitope on human podoplanin. D2-40 immunoreactivity is therefore highly sensitive and specific for lymphatic endothelium. Recent investigations have shown widespread applications of immunohistochemical staining with D2-40 in evaluating podoplanin expression as an immunohistochemical marker for diagnosis and prognosis in various tumors. To determine whether the podoplanin (D2-40) antibody may be useful for the diagnosis of soft tissue tumors, 125 cases, including 4 kinds of benign tumors, 15 kinds of malignant tumors and 3 kinds of tumor-like lesions were immunostained using the D2-40 antibody. Total RNA was extracted from frozen tumor tissue obtained from 41 corresponding soft tissue tumor patients and 12 kinds of soft tissue tumor cell lines. Quantitative real-time PCR reactions were performed. Immunohistochemical and quantitative real-time RT-PCR analyses demonstrated the expression of the podoplanin protein and mRNA in the majority of benign and malignant soft tissue tumors and tumor-like lesions examined, with the exception of alveolar soft part sarcoma, embryonal and alveolar rhabdomyosarcoma, extraskeletal Ewing's sarcoma/peripheral primitive neuro-ectodermal tumor and lipoma, which were completely negative for podoplanin. Since it is widely and highly expressed in nearly all kinds of soft tissue tumors, especially in spindle cell sarcoma, myxoid type soft tissue tumors and soft tissue tumors of the nervous system, podoplanin is considered to have little value in the differential diagnosis of soft tissue tumors.

Myxoid malignant fibrous histiocytoma of the ovary: a case report

A 46-year-old woman presented with whole abdominal discomfort, and imaging revealed a 3-cm-sized ill-defined ovarian mass with extensive peritoneal carcinomatosis. Histologic examination showed malignant fibrous histiocytoma of ovary with predominant myxoid stroma. Microscopic examination showed a highly cellular neoplasm composed of fibroblast-like cells with a predominant myxoid stroma and high pleomorphism and mitotic activity. Immunohistochemically, the tumor was negative for smooth muscle actin, desmin, S-100, pancytokeratin, c-kit, epithelial membrane antigen, and calretinin. Malignant fibrous histiocytoma of ovary is extremely rare, with only six previously reported cases. To the best of our knowledge, the myxoid type of malignant fibrous histiocytoma of ovary has not been previously reported in the English literature except for a case arising in a dermoid cyst of ovary. We present the case and briefly discuss the differential diagnosis.

Accuracy of core-needle biopsy after contrast-enhanced ultrasound in soft-tissue tumours

Percutaneous biopsies are gaining acceptance in the diagnosis of soft-tissue tumours. Sampling in the most representative area is not easy in sarcomas of huge dimension. We hypothesised that ultrasound (US) contrast medium could identify the representative area for focus core-needle biopsy (CNB) METHODS: This is a retrospective cohort series of 115 soft-tissue masses treated from January 2007 to November 2008. Accuracy of US-guided CNB after contrast-enhanced US (CEUS) was determined by comparing the histology of the biopsy with the definitive diagnosis in 105 surgically excised samples (42 benign, 63 malignant) and with the expected outcome in the remaining ten malignant cases not surgically treated. A myxoid component was present in 21 sarcomas (34.4%). Of samples, 94.8% were adequate for diagnosis with 97.1% sensitivity and 92.5% specificity. Sensitivity and specificity in specific histopathological subgroupings were 100%, and in grading definition they were 100% and 96.8%. US-guided CNB is safe and effective. US contrast medium depicts tumour vascular supply and identifies the representative area(s) for sampling. Sensitivity and specificity are also high in subgrouping and grading, including myxoid types. Discussion about biopsy is part of the essential multidisciplinary strategy for these tumours.

Elastofibroma in Ligamentum Flavum in a Patient With Symptoms of Spinal Stenosis: Yet Another Case Report

It is with great interest that I read the article by Daum et al titled “Elastofibromatous changes in tissues from spinal biopsies. A degenerative process afflicting a small but important subset of patients operated for spinal canal compression: report of 18 cases.” This seminal article together with 2 previous case reports constitute the whole literature on the subject. I wish to share a case with striking similarities to this clinicopathological entity. Recently, I was faced with biopsy material from a significantly thickened ligamentum flavum at the level of L4-L5 of a 53-year-old man with clinical symptoms of spinal stenosis. The altered ligamentum flavum warranted a biopsy with a clinical diagnosis of suspected granulomatous process. The biopsy material consisted of whitish firm tissue measuring 1.5 × 1.5 × 0.5 cm. Hematoxylin and eosin–stained sections showed cell-poor connective (ligament) tissue with surrounding fat and striated muscle tissue. The connective (ligament) tissue focally showed a preserved parallel structure of the collagen fibers but mostly displayed degenerative changes of myxoid type with pseudocystic spaces wherein clumps of fibrinoid material were found. Scattered areas of chondroid metaplasia were seen intermingled with areas showing myxoid degeneration. No inflammation was present. Throughout the degenerative areas with a predilection for regions with pseudocystic structures, irregular thick fibers, clumps, cords, and globoid structures composed of thick eosinophilic material separated by swollen collagen were present (Figure 1). On a van Gieson–Verhoeff elastin stain, these structures stained black and displayed the morphological features of pathological elastin (Figure 2). These findings show a striking similarity to the pictures and verbal descriptions of the elastofibromatous changes in spinal biopsies presented in the article by Daum et al. Also present, both in some of the cases presented by the authors and in the case presented herein, were regularly arranged elastic tissue fibers devoid of thick, fragmented globoid clumps of elastin, representing native ligament tissue. Of note is that 4 of the 18 cases presented by the authors, in addition to having symptoms of spinal cord compression, also displayed a thickening of the ligamentum flavum. All these patients were female (age 54-76 years), whereas the patient presented here is a man of similar age. Reportedly, 2 of these patients had disc herniation/

Clinico-pathologic patterns of extremity liposarcoma

Liposarcoma is a tumour derived from primitive cells that undergo adipose differentiation. To describe the clinico-pathological pattern of extremity liposarcoma in Lagos, Nigeria. This is a descriptive study of patients with histologically established liposarcoma affecting the extremities seen at the Oncology unit of the National Orthopaedic Hospital, Lagos Nigeria. Demographic and clinical data ( including age, gender, presenting complaints anatomic location of lesions ), histologic type, clinical stage and treatment outcome were collected using a prepared proforma and analysed. Liposarcoma accounted for 6 [27.3%] of 22 cases of soft tissue sarcomas seen within the study period. All 6 were males with a M:F of 6:0. The age range was 36- 59 years. Lesions were mostly located in the thigh 5/6 (83.3%). The most common histologic type was myxoid seen in 3/6 [50%]. All presented at stage T2bNoMo. Five (83.3%) had limb salvage surgery with adjuvant radiotherapy while one had ablative surgery. Survival and recurrent rates could not be determined as all patients were lost to follow-up soon after surgery. Liposarcoma is the commonest extremity soft tissue sarcoma seen in our centre, the myxoid type being the commonest histologic subtype.

Modified Classification of MRI Findings to Predict Histologic Grading of Liposarcomas

Purpose: To predict the histopathologic grading of liposarcomas with the modified classification of MRI findings. Materials and Methods: The 47 MRI studies of pathologically confirmed liposarcomas were retrospectively analyzed, and found to have well-differentiated (n=17) and myxoid (n=16) types, representing the 'low grade' sarcomas, as well as the round cell (n=9) and pleomorphic (n=5) types, which represent the 'high grade' sarcomas. The MRI findings of liposarcomas were classified into four groups as the one with fat signal above 80%, 20-80%, below 20%, and no fat signal on T1-weighted images (WIs), into three groups as the one with high signals with reticular or irregular lines, homogeneous above 50% of the area, and heterogeneous above 50% on the T2WIs, and into three groups as the one enhanced with reticular or irregular lines and enhancement areas above 50% and below 50% on the Gd-DTPA T1WIs. Results: The sarcomas with a lower amount of fat signals on T1WIs had a significantly higher histologic grade (p = 0.026) and also showed heterogeneous high signals above 50% on the T2WIs was statistically significant difference (p = 0.010) but not on the contrast enhanced T1WIs (p = 0.070). Conclusion: The modified classification of the MR findings could help predict the histologic grading of liposarcomas.

Immunohistochemical Expression of S100A6 in Cellular Neurothekeoma: Clinicopathologic and Immunohistochemical Analysis of 31 Cases

Neurothekeoma is a term introduced by Gallager and Helwig describing a superficial tumor of purported nerve sheath derivation, with cellular and myxoid types. Recently, it has been suggested that the cellular type does not have nerve sheath differentiation. This subtype represents an uncommon neoplasm and sometimes can be problematic to diagnose because it can be easily mistaken for melanoma. We studied the immunohistochemical features of 31 cases of cellular neurothekeomas to evaluate their immunoprofile. Immunohistochemical studies were performed in all 31 cases with formalin-fixed paraffin-embedded tissue sections with antibodies against S100 protein, S100A6, and melanoma antigen recognized by T-cells (MART-1). In addition, 8 cases were evaluated for HMB-45 antigen, keratin (with a pankeratin cocktail), epithelial membrane (EMA), and smooth muscle antigen (SMA). The lesions were from 8 men and 23 women aged 6-64 years (mean 35 years). Four tumors were located on the nose; 4 scalp; 4 finger; 3 thigh; 2 shoulder; 2 wrist; 2 hand; and 1 each on pelvis, cheek, toe, chest, eyebrow, forearm, penis, axilla, mouth, and leg. All tumors were positive for S100A6 (100%) and negative for cytokeratin, HMB-45 antigen, MART-1, and EMA (100%); 29 cases were negative for S100 protein (93.5%; the 2 positive cases had only scattered cells labeled), and only 2 cases were focally positive for SMA (7.5%). Therefore, the combination of strong immunoreactivity for S100A6, in nested dermal spindle cell proliferations, and lack of S100 protein or keratin, supports a diagnosis of cellular neurothekeoma.

Thallium-201 chloride scintigraphy in soft tissue tumors

We report the findings of Thallium-201 chloride ((201)TlCl) scintigraphy and consider how to use this technique to evaluate the character of soft tissue lesions. We enrolled 91 consecutive patients (45 males and 46 females, age range 8-91-years-old). Nineteen patients were malignant and 72 were benign. Patients were scanned 15 minutes (early phase) and 3 hours (delayed phase) after (201)TlCl injection. More intense uptake in the lesion compared to the normal side was considered as 'high', the same degree of uptake was considered 'iso', and decreased uptake was 'low'. The retention index (RI) was calculated in 9 patients in the malignant group and in 16 patients in the benign group. In malignant tumors, 15 of 19 patients showed high uptake in both the early and delayed phases. One malignant fibrous histiocytoma patient was high only in the delayed phase and 1 liposarcoma patient was high only in the early phase. Two liposarcoma patients showed an iso uptake in both phases. One of these patients was pathologically diagnosed as a myxoid type. In benign lesions, no lipoma showed increased uptake. All neurogenic tumors except for 2 demonstrated high uptake. All 3 ganglions of the lower extremities showed iso uptake. Most inflammatory diseases showed increased uptake. Clinically-considered benign patients consisted of tumorous lesions or inflammatory disease. Only 2 patients were considered 'low', and these were diagnosed as intramuscular hematoma and cyst. RI was variable in both malignant and benign lesions and no statistically significant difference was seen between malignant and benign lesions by t-test (p=0.72). A high (201)TlCl uptake lesion is more frequently seen in malignant tumors, but regardless of whether the tumor is benign or malignant, according to the histopathological variety, the (201)TlCl uptake pattern can not be the only indicator to differentiate malignant from benign tumors. We ultimately need to evaluate the nature of tumors by a combination of several imaging techniques.

Midfacial degloving approach to myxoid type nodular fasciitis of the maxilla in a 16-month-old female

Nodular fasciitis is a rare, benign tumor of mesenchymal fibroblasts arising from the deep fascia or bony periostium and presents as a mass in the subcutaneous tissues. Due to its rapid growth, it may mimic a malignant lesion. In children, the myxoid type of nodular fasciitis (also termed infiltrative fasciitis, pseudosarcomatous fasciitis, or pseudosarcomatous fibromatosis) is most common with involvement of the head and neck. To date, four cases of nodular fasciitis specifically involving the maxilla have been reported, only one of which includes a description of the surgical approach. This case report describes a 16-month-old female with nodular fasciitis of the nasolabial groove arising from the maxilla. The objective is to discuss and illustrate the imaging appearance of this rare maxillary location of myxoid fasciitis and to describe the successful resection of the mass utilizing the midfacial degloving approach.

Stromal cells promote bone invasion by suppressing bone formation in ameloblastoma

To study the stromal variation and role of stromal-tumour cell interaction in impaired bone formation as well as enhanced bone resorption in ameloblastoma. Four types of stroma were observed histologically; fibrous, desmoplastic, myxoid and myxoid with hyalinization. Osteoblast and osteoclast were counted using haematoxylin and eosin sections and immunohistochemistry with CD68. After histomorphometric analysis, only fibrous and myxoid types of stroma were distinctly identified. Secreted frizzled-related peptide (sFRP)-2, transforming growth factor-beta 1 and receptor activator of nuclear factor-kappaB ligand (RANKL) revealed strong expression in myxoid type compared with the normal stroma. Bone morphogenetic protein (BMP)-2 was negative in myxoid type, but positive in normal stroma. Fibrous-type stroma showed weak expression of all antigens except RANKL compared with myxoid type. The results suggest that stroma does not act only in bone resorption, but also in the suppression of new bone formation. sFRP-2 is the main factor for impaired bone formation. The expression of markers related to osteoclastogenesis and suppression of osteoblast formation is higher in myxoid-type than in fibrous-type stroma. Tumour cells create a favourable environment for impaired bone formation by secreting sFRP-2 as well as bone resorption by secreting RANKL and interleukin-6.

Adult extrarenal Wilms tumor of the uterus with teratoid features

The present article reports for the first time a case of an extrarenal teratoid Wilms tumor in the uterus of a 62-year-old woman. It had triphasic histology with epithelial areas composed of metanephric tubules harboring glomerular structures, adamantine patterns, neural type rosettes, blastema, and a primitive, myxoid type stroma. Abundant heterologous elements such as cartilage, striated muscle, squamous epithelium, and an alpha fetoprotein and TTF1-positive early endodermal epithelium were also present. Immunohistochemistry in Wilms tumor areas showed positivity for markers also indicative of peripheral primitive neuroectodermal tumors such as neuron-specific enolase, CD99, and CD56. However, nuclear positivity for Wilms tumor antigen together with the presence of glomeruli and the absence of endometrioid tumor areas and the organoid arrangement of tissues excluded peripheral primitive neuroectodermal tumors, carcinosarcoma, and teratoma, respectively. Although the diagnosis of female genital tract Wilms tumors is difficult in cases where glomerular structures are lacking, it should be considered because these neoplasms have a better therapeutic response than peripheral primitive neuroectodermal tumors and carcinosarcoma.

Scope of FNAC in the diagnosis of soft tissue tumors-A study from a tertiary cancer referral center in India

BackgroundFine needle aspiration cytology (FNAC) forms one of the first diagnostic tools in the evaluation of tumors. Its role in diagnosing soft tissue tumors (STT) has been fairly documented, as well as debated. Present study was aimed at evaluating its scope in diagnosing 127 cases of soft tissue tumors.MethodsConventional Pap and MGG staining was available in all the cases. Immunocytochemistry (ICC) was performed in 15 cases. Histopathological details were available in 115 cases.Results50% cases were referred for a primary diagnosis, while 26.8% & 22.8% cases were evaluated for recurrent and metastatic lesions, respectively. Extremities were the commonest sites. On FNAC, 101 cases (79.5%) were labeled as malignant, whereas 10 cases (7.9%) were labeled as benign. The remaining 16 cases (11%) were not categorized and were labeled as 'unsure/not specified'. Histopathological confirmation in 115 cases, gave a diagnostic accuracy of 98%, with a positive predictive value of 98% in malignant cases and a negative predictive value of 100% in benign cases. Two cases were false positive. Among the various cytological categories, 60 cases (47.2%) were of spindle cell type, followed by 32 (25.2%) of round cell type and 14 cases (11%) of lipomatous type. Other 12 cases (9.4%) were of pleomorphic type; 7 (5.5%) cases of epithelioid type and remaining 2 cases were of myxoid type. All the round cell, pleomorphic and myxoid type of tumors were sarcomas, whereas 73.3% cases of spindle cell type were labeled as 'malignant'. Exact cytological sub typing was offered in 58 cases, with rhabdomyosarcoma (RMS) as the most frequently sub typed tumor. The two false positive malignant cases were of fibromatosis and a pigmented schwannoma, on biopsy. Out of 28 metastatic lesions, lymph nodes were the commonest site for metastasis, with epithelioid tumors that formed highest percentage of metastatic cases.ConclusionFNAC is fairly specific and sensitive in STT diagnoses for primary, recurrent and metastatic lesions. The cytological types, especially round cell and pleomorphic sarcomas, can be quickly identified. Clinicopathological correlation with ICC as an adjunct, are valuable in exact sub typing.

A novel type of EWS– CHOP fusion gene in myxoid liposarcoma

The cytogenetic hallmark of myxoid type and round cell type liposarcoma consists of reciprocal translocation of t(12;16)(q13;p11) and t(12;22)(q13;q12), which results in fusion of TLS/ FUS and CHOP, and EWS and CHOP, respectively. Nine structural variations of the TLS/ FUS– CHOP chimeric transcript have been reported, however, only two types of EWS– CHOP have been described. We describe here a case of myxoid liposarcoma containing a novel EWS– CHOP chimeric transcript and identified the breakpoint occurring in intron 13 of EWS. Reverse transcription-polymerase chain reaction and direct sequence showed that exon 13 of EWS was in-frame fused to exon 2 of CHOP. Genomic analysis revealed that the breaks were located in intron 13 of EWS and intron 1 of CHOP.

A Study of Oral Irritation Fibroma with Special Reference to Clinicopathological and Immunohistochemical Features of Stromal Spindle Cells

Background. Oral irritation fibromas (OIFs) are benign fibroblastic proliferations arising from the oral mucosa in response to chronic irritation. Although the nature of fibroblast proliferation has been well studied in wound repair, details of the histopathogenesis of spindle cells in relation to their immunohistochemical features and distribution in OIF are unclear. Methods. Forty cases of OIF were investigated and the spindle cells were examined in detail. The stromas were classified histopathologically, and stained histochemically by the alcian blue (pH-2.5)-PAS double-staining method. Immunohistochemistry was performed using antibodies against vimentin, α-smooth muscle actin (α-SMA), desmin, S-100β, myoD1, and collagen type I and III. Results. Histopathologically, the stromas of OIFs were classified into five types : mature, immature fibroblastic, immature inflammatory, myxoid and mixed type. Inflammation was only seen in a minority of cases with no mitotic figures or any sign of necrosis. Histochemically, the myxoid type stained basophilic while the collagen of other OIF types stained acidophilic. Immunohistochemically, the spindle cells of the mature type expressed vimentin constantly (V phenotype). In contrast, the spindle cells of the immature fibroblastic type expressed α-SMA (VA phenotype) and the immature inflammatory type expressed desmin (VD phenotype). Interestingly, the spindle cells of the myxoid type expressed S-100β (N phenotype), while the mixed type exhibited α-SMA and S-100β positive cells (VA/N phenotype). MyoD1 was expressed constantly in spindle cells of the immature inflammatory and fibroblastic types, but its expression was weak in the mixed type. MyoD1 was not expressed in the mature or myxoid types. All 40 cases stained positive for collagen type III, while collagen type I was detected predominantly in the mature type and only weakly in the other types. Conclusion. These results suggest that spindle cells of OIFs transiently express myofibroblastic characteristics, particular the VA, VD and VA/N phenotypes, through the expression of α-SMA, desmin and myoD1. Thus, with the onset of trauma (weak or chronic irritation) a myofibroblastic stromal reaction appears to be evoked in undifferentiated mesenchymal cells, and collagen type III is produced. As the healing progress proceeds, collagen type III levels decline, collagen type I is secreted and the phenotypic features of myofibroblasts disappear, as seen in the V phenotype. The myxoid type expressed immunohistochemical features of neural differentiation while the mixed type expressed features considered to be of dual origin. The immunohistochemical findings also revealed that the growth of OIF was time-dependent.

Rhabdomyoma of the Head and Neck Demonstrated by Prenatal Magnetic Resonance Imaging

A case of fetal rhabdomyoma (myxoid type) of the head and neck demonstrated on prenatal magnetic resonance imaging (MRI) is presented. This benign tumor of skeletal muscle is uncommon and should not be confused with its malignant counterpart-rhabdomyosarcoma. With the increasing use of ultrafast MRI, the radiologist is more likely to encounter head and neck masses in the fetus.

Recurrent pleomorphic adenomas of the parotid gland

Ten patients (9 females and 1 male) with recurrent pleomorphic adenomas of the parotid gland were investigated clinically. Two of them were treated primarily in our hospital, 6 were treated by other otolaryngologists and 2 were treated by general surgeons. The cause of recurrence depends on the tumor type, their capsule and initial treatment. Partial parotidectomy is the first procedure that should be performed in these cases.Surgery was performed in all 10 patients: total parotidectomy in 1, partial parotidectomy in 7, and tumor enucleation in 2. The myxoid type and multiple tumor were the most common recurrent tumors. Tumors recurred again in 3 of our cases that had not undergone resection of their incision scars. Complete resection of the tumor and the surrounding scar is essential in the treatment of a recurrent tumor. Although preservation of the facial nerve is important, it is sometimes necessary to cut the nerve. These tumors can become malignant, so the management of each recurrent tumor should be monitored carefully.