Résumé
A pyogenic granuloma is one of the most common benign tumors in the head and neck. However, it rarely occurs in the external auditory canal (EAC). We report a case of a pyogenic granuloma that involved the both EAC in a pregnant woman. The clinical manifestation is discussed with a literature review.
Sujets)
Femelle , Humains , Grossesse , Conduit auditif externe , Granulome pyogénique , Tête , Cou , Femmes enceintesRésumé
BACKGROUND: Thymosin β₄ is a multi-functional hormone-like polypeptide, being involved in cell migration, angiogenesis, and tumor metastasis. This study was undertaken to clarify the clinicopathologic implications of thymosin β₄ expression in human colorectal cancers (CRCs). METHODS: We investigated tissue sections from 143 patients with CRC by immunohistochemistry. In addition, we evaluated the expression patterns and the clinico-pathological significance of thymosin β₄ expression in association with hypoxia inducible factor-1α (HIF-1α) expression in the CRC series. RESULTS: High expression of thymosin β₄ was significantly correlated with lymphovascular invasion, invasion depth, regional lymph node metastasis, distant metastasis, and TNM stage. Patients with high expression of thymosin β₄ showed poor recurrence-free survival (p = .001) and poor overall survival (p = .005) on multivariate analysis. We also found that thymosin β4 and HIF-1α were overexpressed and that thymosin β₄ expression increased in parallel with HIF-1α expression in CRC. CONCLUSIONS: A high expression level of thymosin β₄ indicates poor clinical outcomes and may be a useful prognostic factor in CRC. Thymosin β₄ is functionally related with HIF-1α and may be a potentially valuable biomarker and possible therapeutic target for CRC.
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Humains , Hypoxie , Mouvement cellulaire , Tumeurs colorectales , Immunohistochimie , Noeuds lymphatiques , Analyse multifactorielle , Métastase tumorale , ThymosineRésumé
An endometrial stromal sarcoma (ESS) is an uncommon uterine neoplasm, and its primary occurrence in the intestine as an extrauterine ESS (EESS) is exceedingly rare. We hereby report a primary EESS arising in the sigmoid colon with a review of the literature. A 52-year-old woman presented with bloody stool and underwent a colon fiberscopy, which revealed a fungating mass obstructing the lumen at the distal sigmoid. A laparoscopic low anterior resection was performed, and an umbilicated polypoid mass was identified; on section, it had infiltrated the mesocolic fat and measured 3.8 cm x 2.5 cm. The tumor showed geographic sheets or nests composed of relatively monotonous stromal cells, expansion or infiltration to the proper muscle and mesocolic fat, and extensive lymphovascular invasion and metastasis to regional lymph nodes and the pelvic peritoneum. The tumor cells were strongly and diffusely immunoreactive for CD10, but negative for c-kit, CD34, and Dog1. Two months later, a hysterectomy with a bilateral salpingo-oophorectomy was performed, and no evidence of an ESS was found in the uterus.
Sujets)
Femelle , Humains , Adulte d'âge moyen , Côlon , Côlon sigmoïde , Hystérectomie , Intestins , Noeuds lymphatiques , Métastase tumorale , Péritoine , Sarcome du stroma endométrial , Cellules stromales , Tumeurs de l'utérus , UtérusRésumé
BACKGROUND: Nodular fasciitis is the most common reactive mesenchymal lesion to be misidentified as a type of sarcoma. HuR is an mRNA-binding protein that can stabilize cyclooxygenase-2 (COX-2) mRNA leading to COX-2 overexpression. The aim of this study is a comparison of the expressions of COX-2 and HuR and the relationships between their expressions and the clinicopathological parameters in nodular fasciitis and low-grade sarcoma. METHODS: We measured the expression of HuR and COX-2 in 21 cases of nodular fasciitis and 37 cases of low-grade sarcoma using immunohistochemistry. RESULTS: The frequency of cytoplasmic immunoreactivity for HuR was 5 of 21 cases of nodular fasciitis (23.8%) and 23 of 37 cases of low-grade sarcoma (62.1%) (p=.013). COX-2 expression was moderate or strong in nodular fasciitis (12/21, 57.1%) and in low-grade sarcoma (29/37, 78.4%) (p=.034). In addition, a significant difference existed between these two entities in terms of the relationship between moderate or strong COX-2 expression and HuR cytoplasmic immunoreactivity (p=.009). Moderate or strong COX-2 immunoreactivity correlated with nuclear (p=.016) or cytoplasmic HuR (p=.024) expression in low-grade sarcoma but not in nodular fasciitis. CONCLUSIONS: This study suggests that HuR and COX-2 expression may be useful to differentiate nodular fasciitis from low-grade sarcoma.
Sujets)
Cyclooxygenase 2 , Cytoplasme , Fasciite , Immunohistochimie , ARN messager , SarcomesRésumé
We report a case of Langerhans cell sarcoma presented as a solitary mass in the left supraclavicular area in a 31-year-old woman. Computed tomography revealed a relatively well-defined and lightly enhancing mass in the left supraclavicular area, measuring 5.5x4.5x3.2 cm. Excision was subsequently performed. Microscopically, the specimen consisted of an enlarged and partially effaced lymph node. Nests of different size composed of atypical tumor cells were located in the paracortex and the medulla of the lymph node. The tumor cells exhibited abundant eosinophilic or clear cytoplasm and displayed marked nuclear atypia and increased mitotic figures. Infiltration of many eosinophils was identified in the periphery and between the tumor cells. The tumor cells were reactive for CD1a and S100 protein. Ultrastructually, they were found to have Birbeck granules in the cytoplasm.
Sujets)
Adulte , Femelle , Humains , Antigènes CD1 , Cytoplasme , Granulocytes éosinophiles , Sarcome à cellules de Langerhans , Noeuds lymphatiquesRésumé
BACKGROUND: Decay accelerating factor (DAF/CD55), regulates the complement system by accelerating decay of the C3 convertase, has been described in several malignancies, however, the clinicopathologic significance of CD55 and its receptor CD97 has not been fully investigated. We examined the expression patterns of both CD55 and CD97 and their association with clinicopathologic parameters in colorectal cancers (CRCs). METHODS: Expression patterns of CD55 and CD97 in the stroma and tumor cells at tumor center and invasive front were examined in 130 CRCs, and their significance was statistically evaluated. RESULTS: CD55-high stroma was correlated with tumor border (p=0.006) and invasion depth (p=0.013). CD55-high tumor cells at tumor center and invasive front were correlated with histologic grade, and CD55-high tumor cells at invasive front with tumor, node and metastasis (TNM) stage (p<0.05). CD97-high stroma was correlated with lymph node metastasis (p=0.016) and TNM stage (p=0.030). CD97-high tumor cells at tumor center and invasive front were correlated with tumor size and CD97-high tumor cells at tumor center with tumor border (p<0.05). Patients with CD55-high stroma showed poor overall and recurrence-free survival (p<0.05) in univariate analysis, and were independently associated with short recurrence-free survival (p=0.025) in multivariate analysis. CONCLUSIONS: Stromal CD55 overexpression would be an indicator of adverse clinical outcome and a useful prognostic factor.
Sujets)
Humains , Antigènes CD55 , Hydroxyde de calcium , Tumeurs colorectales , Complement C3-C5 Convertases , Protéines du système du complément , Immunohistochimie , Noeuds lymphatiques , Métastase tumorale , Oxyde de zincRésumé
BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common endocrinopathy causing anovulation in women of childbearing age. It has been well established that estrogen receptor-alpha knockout (ERalphaKO) mice display several pathologic ovarian phenotypes of PCOS. The aims of this study were to determine ovarian pathology in new ERalphaKO mice using a CreloxP approach and intra-ovarian ERalpha function as regulating key aspects of PCOS. METHODS: ERalphaKO mice, which were deficient in exon 3 of the ERalpha gene, were used. Immunohistochemical studies were done on ovaries of control and ERalphaKO mice using antibodies specific to ERalpha, ERbeta, inhibin-alpha, and alpha-smooth muscle actin (SMA), as well as histochemical staining using Sudan black-B. RESULTS: All ovaries of ERalphaKO mice were larger than control mouse ovaries and displayed a disrupted theca-interstitial tissue organization, multiple atretic follicles and multiple hemorrhagic cysts. None of the ERalphaKO mouse ovaries showed a corpus luteum. In addition, heavy deposition of Sudan black-B positive foamy cells was seen. The theca externa of preantral immature follicles and hemorrhagic cysts showed strong expression of alpha-SMA. CONCLUSIONS: ERalphaKO mice show hemorrhagic polycystic ovaries and hyperplasia of the theca externa. This study demonstrates that the ERalpha is the functional key to the pathogenesis of PCOS.
Sujets)
Animaux , Femelle , Humains , Souris , Actines , Anovulation , Anticorps , Corps jaune , Récepteur alpha des oestrogènes , Récepteur bêta des oestrogènes , Oestrogènes , Exons , Hyperplasie , Immunohistochimie , Souris knockout , Muscles , Follicule ovarique , Ovaire , Phénotype , Syndrome des ovaires polykystiques , Soudan , Cellules thécalesRésumé
PURPOSE: Phyllodes tumors (PTs) of the breast have been classified as benign, borderline, or malignant based on their histopathologic features. However, predicting clinical behavior based on these features has proven to be difficult given that local recurrence occurs in both benign and malignant PTs. Recurrence has been shown to mirror the histologic pattern of the primary tumor or to show dedifferentiation. The aim of this study was to assess the value of the histopathologic parameters, expression or mutation of c-Kit and platelet derived growth factor receptor alpha (PDGFRA) in predicting tumor recurrence. METHODS: Representative areas from 39 benign, 16 borderline, and 12 malignant PTs were selected for construction of tissue microarrays. Immunohistochemical analyses for p53, Ki-67, c-Kit, and PDGFRA were performed and SSCP-PCR analysis was carried out to identify mutations in exons 9, 11, 13, and 17 of the c-Kit gene and exons 12 and 18 of the PDGFRA gene. Clinicopathologic features, including tumor recurrence and margin status, were also evaluated. RESULTS: Of the 67 PTs, 11 cases (16.4%) recurred from 3 to 92 months following initial diagnosis (4 benign, 2 borderline, and 5 malignant). One benign PT case recurred as a borderline tumor and two borderline PT cases recurred as malignancies. Three patients died of malignant PT. No mutations of the c-Kit or PDGFRA genes were found and there was no statistically significant association of either p53 or p16 immunostaining with recurrent disease (p>0.05). However, histologic grade (p=0.033), margin status (p<0.001), Ki-67 (p=0.012), c-Kit (p=0.002), and PDGFRA (p=0.007) stromal immunopositivity were significantly correlated with recurrence. CONCLUSION: Even though positive or close margins were significantly associated with tumor recurrence, stromal c-Kit, PDGFRA positivity, and the Ki-67 index were useful for predicting recurrent PTs. Despite this, no c-Kit or PDGFRA mutations were found.
Sujets)
Humains , Région mammaire , Exons , Tumeur phyllode , Protéines proto-oncogènes c-kit , Récepteurs aux facteurs de croissance dérivés des plaquettes , RécidiveRésumé
Synovial sarcoma is a rare renal neoplasm that is not easy to diagnose unless SYT-SSX fusion transcripts are identified. We report here on a case of primary renal synovial sarcoma in a 35-year-old woman. A mass was discovered by accident in the lower part of the right kidney when ultrasonography was performed, and it was removed via radical nephrectomy. Grossly, the tumor was a homogeneously tan-brown soft mass that measured 4.5x3.2x3.0 cm, and it was encircled by a well-defined cystic space. The lesion exhibited hypercellularity of the oval or short spindle cells that were arranged in various solid sheets or intersecting fascicles. Immunohistochemically, the tumor showed diffuse positivity for vimentin, bcl-2 and CD99, and it showed focal positivity for epithelial membrane antigen. The SYT-SSX fusion transcripts were detected by reverse transcription-polymerase chain reaction (RT-PCR). Synovial sarcoma should be considered in the differential diagnosis when a spindle cell neoplasm is encountered in the kidney.
Sujets)
Adulte , Femelle , Humains , Diagnostic différentiel , Rein , Tumeurs du rein , Mucine-1 , Néphrectomie , Protéines de fusion oncogènes , Sarcome synovial , VimentineRésumé
BACKGROUND: KIT and PDGFRA are tyrosine kinase receptors. Stem cell factor/KIT-mediated signaling plays a role in normal spermatogenesis, and the alteration of KIT is important in the pathogenesis of seminomas/dysgerminomas (SD). METHODS: To determine the role of expression and mutation of the KIT and PDGFRA genes, we analyzed 16 seminoma cases, 4 spermatocytic seminoma (SS) cases and 8 dysgerminoma cases for KIT and PDGFRA expression and mutation of KIT (exons 9, 11, 13, and 17) and PDGFRA (exons 12 and 18) using PCR-SSCP methods. RESULTS: KIT was immunohistochemically positive in all 24 SD cases, and one of four (25%) SS cases. PDGFRA was immunohistochemically evident in 16 of the 24 (66.6%) SD cases, and two of the four (50%) SS cases. KIT expression was significantly reduced in SS compared with seminoma (p=0.0035). Four cases (14.3%) displayed mutation in KIT exon 17 or PDGFRA exon 12. Distant metastasis was present in three cases (10.7%), one of which had a nonsense mutation in KIT. CONCLUSIONS: These results indicate that KIT is expressed in the majority of SD cases, but not in most SS cases. However, there was no significant correlation between the clinicopathologic features and mutation or expression of KIT and PDGFRA.
Sujets)
Codon non-sens , Dysgerminome , Exons , Métastase tumorale , Protéines proto-oncogènes c-kit , Récepteurs à activité tyrosine kinase , Récepteur au PDGF alpha , Séminome , Spermatogenèse , Cellules souchesRésumé
Primary lymphoma arising from the uterine cervix has been rarely encountered, and breast involvement is rare because of the relative paucity of lymphoid tissue in the breast. A 32-year-old woman with a primary malignant lymphoma of the uterine cervix and breast involvement is reported. The patient presented with post-coital vaginal bleeding, and punch biopsy of the cervix revealed the diffuse large B cell type of malignant lymphoma. PET-scan was done for staging, and abnormal FDP uptakes were detected in a uterine cervical mass and breast nodule. Ultrasonography-guided needle biopsy was done for the breast mass, and 2 biopsied nodules revealed fibroadenoma and diffuse large B cell lymphoma. The patient (Ann Arbor stage IV) was treated with 6 cycles of combination chemotherapy with CHOP plus rituximab. The patient went into complete remission. Thereafter, 4500cGy pelvic irradiation was done for adjuvant therapy.
Sujets)
Adulte , Femelle , Humains , Anticorps monoclonaux d'origine murine , Biopsie , Ponction-biopsie à l'aiguille , Région mammaire , Col de l'utérus , Association de médicaments , Fibroadénome , Formycines , Tissu lymphoïde , Lymphomes , Lymphome B , Lymphome malin non hodgkinien , Ribonucléotides , Hémorragie utérine , RituximabRésumé
BACKGROUND: Cyclin-dependent kinase-associated phosphatase (KAP) is a human dual-specificity protein phosphatase that dephosphorylates Cdk2 on threonine160 in a cyclin-dependent manner and that is known as an up-regulated molecule in some malignant tumors. We investigated the expression and clinicopathologic significance of KAP protein in relation to tumorigenesis of colorectal carcinoma. METHODS: The expression patterns of KAP protein in tumor tissue were examined by reverse transcription-PCR and immunohistochemical staining. RESULTS: An enhanced transcriptional level of KAP mRNA was observed in 11 out of 12 colorectal carcinoma specimens. Immunohistochemical examination showed that KAP protein was more highly expressed in the tumors than that in the adjacent non-neoplastic mucosal tissues for 52 of 102 colorectal cancer tissues. The statistical analysis showed that an increased level of KAP protein in the colorectal cancer tissues was inversely correlated with the histologic grade, tumor size and Duke's stage. CONCLUSION: The present study suggests that alteration of KAP might play a role, at least in part, in the tumorigenicity of colorectal carcinoma through the mechanism of cell cycle regulation.
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Humains , Carcinogenèse , Cycle cellulaire , Tumeurs colorectales , Immunohistochimie , Muqueuse , ARN messagerRésumé
Gastrointestinal stromal tumor (GIST) is the most common non-epithelial neoplasm arising in the gastrointestinal tract, but this tumor is rarely seen in association with type 1 neurofibromatosis (NF-1). We report here on two cases of multiple GISTs of the small intestine that occurred in NF-1 patients. We also analyzed the mutations of c-kit exons 9, 11, 13 and 17 and the plateletderived growth factor receptor-alpha (PDGFRA) exons 12 and 18 in two GIST patients. Histologically, the NF-1-associated GISTs were similar to those of non-the NF-1 GISTs, but they characteristically revealed hyperplastic interstitial cells of Cajal around the GISTs. Immunohistochemically, these tumors showed strong co-expressions of CD117 and CD34. The molecular genetic analysis of the GISTs showed that all of the c-kit and PDGFRA exons that were analyzed in the GISTs of the two patients were the wild-type, suggesting a limited role for the c-kit and PDGFRA mutations in the tumorigenesis of NF-1-associated GISTs.
Sujets)
Humains , Carcinogenèse , Exons , Tumeurs stromales gastro-intestinales , Tube digestif , Cellules interstitielles de Cajal , Intestin grêle , Biologie moléculaire , Neurofibromatoses , Neurofibromatose de type 1Résumé
To evaluate the expressions of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in thyroid neoplasms in a Korean population, we studied a total of 154 cases: papillary carcinoma of classical type (PTC), 86; follicular adenoma (FA), 21; follicular carcinoma (FC), 35; medullary carcinoma (MC), 3; undifferentiated carcinoma (UC), 5; and Hurthle cell neoplasm (HN), 4. Using immunohistochemical staining, COX-2 expression was detected in 62 (72.1%) PTC specimens, 5 (23.8%) FA specimens, 10 (28.6%) FC specimens, 0 (0.0%) MC specimens, 1 (20.0%) UC specimen, and 3 (75%) HN specimens. iNOS expression was detected in 66 (76.7%) PTC specimens, 4 (19.0%) FA specimens, 13 (37.1%) FC specimens, 0 (0.0%) MC specimens, 3 (60.0%) UC specimens, and 4 (100%) HN specimens. The results showed that COX-2 and iNOS were frequently expressed in the PTC and HN specimens, and iNOS was more frequently overexpressed in the FC specimens than in the FA specimens. In PTC, COX-2 and iNOS were significantly overexpressed in patients over 45 yr of age (p=0.029, p=0.041), and iNOS expression was increased in patients with a large primary tumor (p=0.028). These results suggest that the upregulation of COX-2 and iNOS may contribute to the tumor progression of thyroid gland, particularly in PTC and HN, and iNOS may play an adjuvant role during the tumor progression of FC.
Sujets)
Adulte d'âge moyen , Mâle , Humains , Femelle , Sujet âgé , Adulte , Marqueurs biologiques tumoraux/analyse , Distribution tissulaire , Tumeurs de la thyroïde/diagnostic , Statistiques , Sensibilité et spécificité , Reproductibilité des résultats , Nitric oxide synthase type II/analyse , Protéines tumorales/analyse , Analyse de profil d'expression de gènes , Cyclooxygenase 2/analyseRésumé
A 30-yr-old man was referred for suspicious rectal cancer because of ulcerated lesions in the rectum and a palpable mass in left inguinal area. Sigmoidoscopy showed two indurated masses and histologic evaluation of biopsy revealed obliterative endarteritis with heavy plasma cell infiltration. Both venereal disease research laboratories (VDRL) and fluorescent treponemal antibody absorption (FTA-ABS) tests were positive. After injection of penicillin G benzathine for 3 weeks, the rectal chancre and the palpable mass disappeared.
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Adulte , Humains , Mâle , Diagnostic différentiel , Maladies du rectum/complications , Tumeurs du rectum/anatomopathologie , Syphilis/complicationsRésumé
We report a case of torsion of a benign cyst arising from the parietal layer of the tunica vaginalis, which presented on an acute scrotum. Physical examination revealed a tender swelling of the left hemiscrotum. Surgical, we happened to find torsion of a cyst originating from the parietal layer of the tunica vaginalis. The pedicle of the cyst was twisted about 360 degrees.
Sujets)
Examen physique , Rabéprazole , ScrotumRésumé
Inflammatory pseudotumors are infrequently occurring lesions, characterized by a localized mass composed of a benign proliferation of inflammatory cells, with varying amount of fibrosis. As a type of inflammatory pseudotumer, eosinophilic cholangitis or eosinophilic pseudotumor are extremely rare, and characterized by eosinophilic cholecystitis and associated extrahepatic biliary obstruction. Herein, we report a case of an eosinophilic pseudotumor of the bile duct in a 37-year old man who was referred to Eulji University Hospital for evaluation of jaundice. From cholangiography and a CT scan, intrahepatic duct dilatation and common hepatic duct obstruction were detected, therefore, common hepatic duct cancer was suspected. After percutaneous biliary drainage, he underwent an operation for bile duct resection and a hepaticojejunostomy. The final pathological finding was that of cholecystitis, with eosinophil and wall thickening of bile duct, accompanied by eosinophil infiltration and fibrosis, which was compatible with eosinophilic pseudotumor. The patient had no subsequent remarkable postoperative course and was discharged with normal liver function.
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Adulte , Humains , Tumeurs des canaux biliaires , Conduits biliaires , Bile , Cholangiographie , Angiocholite , Cholécystite , Dilatation , Drainage , Granulocytes éosinophiles , Fibrose , Granulome à plasmocytes , Conduit hépatique commun , Ictère , Foie , TomodensitométrieRésumé
Concurrent hyperthyroidism and primary hyperparathyroidism in the same patient is rare. In most cases of concomitant hyperthyroidism and primary hyperparathyroidism, serum calcium levels are quite elevated. However, recently we diagnosed a patient who had hyperthyroidism [Triiodothyroxine 6.81 nmol/L (1.23-3.39), Free thyroxine 92.88 pmol/L (10.32-25.80), TSH 0.05 mU/L (0.2-7.0)] and primary hyperparathyroidism [parathyroid hormone 163 pg/mL (12-72)] with mild hypercalcemia 2.78 mmol/L (2.03-2.60)]. We treated this patient with propylthiouracil and pamidronate and normalized her thyroid function and serum calcium levels. We then performed subtotal thyroidectomy and removed two parathyroid glands and clipped one parathyroid gland using a hemoclip. The pathologic diagnosis was confirmed to be Graves' disease and parathyroid hyperplasia. The patient was healthy, and serum levels of PTH, calcium and phosphorus were normal after the operation.
Sujets)
Humains , Calcium , Diagnostic , Maladie de Basedow , Hypercalcémie , Hyperparathyroïdie , Hyperparathyroïdie primitive , Hyperplasie , Hyperthyroïdie , Glandes parathyroïdes , Phosphore , Propylthiouracile , Glande thyroide , Thyroïdectomie , ThyroxineRésumé
Concurrent hyperthyroidism and primary hyperparathyroidism in the same patient is rare. In most cases of concomitant hyperthyroidism and primary hyperparathyroidism, serum calcium levels are quite elevated. However, recently we diagnosed a patient who had hyperthyroidism [Triiodothyroxine 6.81 nmol/L (1.23-3.39), Free thyroxine 92.88 pmol/L (10.32-25.80), TSH 0.05 mU/L (0.2-7.0)] and primary hyperparathyroidism [parathyroid hormone 163 pg/mL (12-72)] with mild hypercalcemia 2.78 mmol/L (2.03-2.60)]. We treated this patient with propylthiouracil and pamidronate and normalized her thyroid function and serum calcium levels. We then performed subtotal thyroidectomy and removed two parathyroid glands and clipped one parathyroid gland using a hemoclip. The pathologic diagnosis was confirmed to be Graves' disease and parathyroid hyperplasia. The patient was healthy, and serum levels of PTH, calcium and phosphorus were normal after the operation.
Sujets)
Humains , Calcium , Diagnostic , Maladie de Basedow , Hypercalcémie , Hyperparathyroïdie , Hyperparathyroïdie primitive , Hyperplasie , Hyperthyroïdie , Glandes parathyroïdes , Phosphore , Propylthiouracile , Glande thyroide , Thyroïdectomie , ThyroxineRésumé
BACKGROUND: Mature cystic teratoma is a common type of ovarian tumor. Although squamous cell carcinoma (SCC) is the most common carcinoma in malignant transformations of ovarian mature cystic teratomas, SCC arising in a mature teratoma is rare. METHODS: This paper reports four cases of invasive SCC, a case of an adenosquamous cell carcinoma and a case of a pure in situ SCC arising in a mature cystic teratoma including a clinicopathological evaluation and an immunohistochemical study of the p53 protein and p21WAF1/CIP1. RESULTS: The mean age of the patients was 60 years. The sizes of the mature cystic teratomas in all cases were greater than 7.5 cm in the largest diameter. Five cases showed the nuclear accumulation of the p53 protein with no p21WAF1/CIP1 immunoreactivity. The other case showed the nuclear accumulation of p21WAF1/CIP1 without p53 expression. There was a significant inverse relationship between the p53 protein level and p21WAF1/CIP1 expression. CONCLUSION: A clinicopathological evaluation showed that a SCC arising from a mature cystic teratoma must be included in a differential diagnosis when the patient is over 42 years of age and the size of a mature cystic teratoma is greater than 75 mm in the largest diameter. It is suggested that p53 overexpression is implicated in the malignant transformation, and the p21WAF1/CIP1 expression level is dependent on alterations in the level of the p53 protein in these tumors.