Sarcomatous Areas Research Articles

Insulin-like Growth Factor 2 Gene Expression Molecularly Differentiates Pleuropulmonary Blastoma and Embryonal Rhabdomyosarcoma.

The sarcomatous element in pleuropulmonary blastoma (PPB) is often histologically indistinguishable from embryonal rhabdomyosarcoma (ERMS). A diagnosis of PPB is often made after definitive surgical resection based on pathologic features, most notably the presence of hamartomatous pulmonary elements. Samples from seven PPB patients were obtained from the rhabdomyosarcomatous portion of the tumor by macrodissection. Representative ERMS tumor tissue was selected from 21 ERMS patient samples. Formalin-fixed paraffin-embedded tissue scrolls from each sample were analyzed using the Affymetrix Human Exon arrays. All PPB patients and 7 of 21 ERMS patients were 3 years old and younger. Twenty transcripts (10 annotated, 10 noncoding RNAs) were significantly differentially expressed in ERMS when compared with PPB samples. Insulin-like growth factor 2 (IGF2) was uniformly overexpressed in ERMS (19/21>400) but was expressed at low levels in PPB (P<0.001). Two ERMS cases that had low level IGF2 expression were 3 years and younger of age. No other differences between the 2 approached this degree of significance, despite a common rhabdomyogenic phenotype in the sarcomatous areas of PPB. PPB, unlike most ERMS, appears not to be driven by autocrine IGF2 signaling.

Pancreatic carcinosarcoma: case report of a rare type of pancreatic neoplasia.

Carcinosarcoma of the pancreas is a rare entity comprising a small subset of all pancreatic neoplasms. Diagnosis is usually established by immunohistochemical examination of the resected specimen. Prognosis is limited to several months after resection. We review the current literature on this rare type of neoplasia, considering histopathological and clinical features. The pathologic findings revealed areas of both adenocarcinoma and sarcoma of the pancreas. The adenocarcinomatous areas localized to the tumor within the head of the pancreas whereas the sarcomatous areas localized to regions of the intraductal component. Carcinosarcoma of the pancreas is a rare disease having a dismal prognosis. To our knowledge, this carcinosarcoma is the very rare reported case of a primary pancreatic neoplasm with mixed carcinomatous and sarcomatous components.

ZFP36-FOSB fusion defines a subset of epithelioid hemangioma with atypical features.

Epithelioid hemangioma (EH) is a benign neoplasm with distinctive vasoformative features, which occasionally shows increased cellularity, cytologic atypia, and/or loco-regional aggressive growth, resulting in challenging differential diagnosis from malignant vascular neoplasms. Based on two intraosseous EH index cases with worrisome histologic features, such as the presence of necrosis, RNA sequencing was applied for possible fusion gene discovery and potential subclassification of a novel atypical EH subset. A ZFP36-FOSB fusion was detected in one case, while a WWTR1-FOSB chimeric transcript in the other, both were further validated by fluorescence in situ hybridization (FISH) and reverse transcription polymerase chain reaction (RT-PCR). These abnormalities were then screened by FISH in 44 EH from different locations with seven additional EH revealing FOSB gene rearrangements, all except one being fused to ZFP36. Interestingly, 4/6 penile EH studied showed FOSB abnormalities. Although certain atypical histologic features were observed in the FOSB-rearranged EH, including solid growth, increased cellularity, mild to moderate nuclear pleomorphism, and necrosis in 3/9 cases, no overt sarcomatous areas were discerned to objectively separate the lesions from the fusion-negative EH. No patient has developed recurrence to date, but the follow-up was relatively limited and short to draw definitive conclusions regarding behavior. Although FOSB-rearranged EH do not show significant morphologic overlap with SERPINE1-FOSB fusion-positive pseudomyogenic hemangioendothelioma, FOSB oncogenic activation is emerging as an important event in these benign and intermediate groups of vascular tumors.

Four cases of solitary fibrous tumour of the eye and orbit: one with sarcomatous transformation after radiotherapy and one in a 5-year-old child’s eyelid

BackgroundSolitary fibrous tumour (SFT) is quite a rare neoplasm involving the eye and the orbit. It is described as showing benign behaviour in adults, but malignant cases are exceptionally reported...

Osteoid differentiation in mesodermal (mullerian) adenosarcoma of ovary

A 55-year-old female presented with abdominal pain and 10 cm mass per abdominal examination. Computerized tomography scan of abdomen and pelvis revealed a heterogeneously enhancing solid cystic mass right ovarian mass and mild ascites. Surgery was performed. Specimens were sent for examination. Microscopic examination revealed an admixture of benign but occasionally atypical appearing mullerian type glands with sarcomatous stroma. Solid area showed undifferentiated tumour cells. Atypical mitoses and necrosis were also seen. Areas with extensive benign osteoid surrounded by fibroblastic stroma were also present. Glandular component showed positivity for CK-7, AE-1 and EMA while sarcomatous areas showed positivity for vimentin only. Mullerian adenosarcoma of ovary with sarcomatous overgrowth (SO) having heterologous component was confirmed. Postoperative 3 cycles of chemotherapy was given and the patient was well till date (three months after surgery).

Combined hepatocellular carcinoma and neuroendocrine carcinoma with sarcomatous change of the liver after transarterial chemoembolization

Primary hepatic neuroendocrine carcinoma is rare and its origin is not clearly understood. An admixture of hepatocellular carcinoma (HCC) and neuroendocrine carcinoma is particularly rare. Here, we report a patient with an extremely rare combination of HCC and neuroendocrine carcinoma of the liver. To our knowledge, this is the first reported case in which the carcinoma showed sarcomatous change. The patient was a 76-year-old man who had received outpatient treatment for chronic hepatitis C. On abdominal computed tomography (CT), the hepatic tumor was enhanced in the arterial phase but its density was lower than that of normal liver in the portal phases. His serum α-fetoprotein (AFP) level was very high. Therefore, transarterial chemoembolization (TACE) was performed based on the diagnosis of HCC. Ten months after TACE, his serum AFP level had increased to the level measured before TACE. Partial hepatectomy was performed because CT revealed poor enhancement of the recurrent tumor. Histopathologically, the tumor consisted of two distinct components: moderately differentiated HCC was intermingled with a neuroendocrine carcinoma, which was accompanied by sarcomatous changes. Immunohistochemically, the neuroendocrine carcinoma cells were positive for CD56, chromogranin A and neuron-specific enolase, and negative for AFP. The sarcomatous area was positive for AE1/3 and CD56, consistent with sarcomatous change of neuroendocrine carcinoma. The neuroendocrine carcinoma and/or sarcomatous change may have been due to phenotypic changes and/or dedifferentiation of HCC induced by TACE. Six months after surgery, the patient was diagnosed with metastasis of the neuroendocrine carcinoma to sacral bone. He died 7 months after surgery.

Adenocarcinoma with sarcomatous dedifferentiation arising from mature cystic teratoma of the anterior mediastinum

Mediastinal teratoma with malignant transformation (TMT) is a very rare condition. A 44-year-old man presented with a large cystic mass of the anterior mediastinum. The tumor was surgically removed. The cystic mass was well demarcated, with an irregularly thickened wall. Histologically, the cystic wall was mainly lined by non-ciliated columnar epithelium and focally by squamous epithelium. A nodular part of the cystic wall revealed well-differentiated adenocarcinoma composed of tubulopapillary structures. Deep in the nodular tissue, neoplastic glands merged into undifferentiated sarcomatous cells. Immunohistochemically, CK7, CK19, and smad-4 were strongly and diffusely positive in adenocarcinoma. CD10 was focally positive on the luminal surface of the glands, and MUC5AC was also focally positive. TTF-1, cdx-2, and CK20 were negative in the adenocarinoma. Sarcomatous area showed diffuse strong positivity for vimentin, but was negative for the aforementioned epithelial markers. About 10 months postoperatively, a left pleural effusion had developed with multiple pleural nodules on computed tomography scan of the chest. The cytologic diagnosis from pleural fluid was metastatic adenocarcinoma. To our knowledge, in the English literature, this is the first case of adenocarcinoma with sarcomatous transformation that has developed in a mature cystic teratoma of the mediastinum and shows pleural metastasis.

Effect of insulin-like growth factor 2 gene expression on pleuropulmonary blastoma and embryonal rhabdomyosarcoma.

9564 Background: The sarcomatous element in pleuropulmonary blastoma (PPB) often cannot be differentiated from embryonal rhabdomyosarcoma (ERMS) by histology, particularly when characteristic elements like cartilage and respiratory mucosa are inapparent. The initial diagnosis is often ERMS. A diagnosis of PPB is based on a combination of clinical (age, location) and pathologic features. We hypothesized that the sarcomatous portions of PPB are a form of ERMS indistinguishable from typical ERMS. We reasoned that a detailed comparison of RNA expression could clarify this hypothesis. Methods: Samples from 7 PPB patients were obtained from the rhabdomyosarcomatous portion of the tumor by macro-dissection after pathologic review of all material. Representative ERMS tumor tissue was selected from 21 ERMS cases. FFPE tissue scrolls from each case were analyzed using Affymetrix Human Exon arrays after RNA extraction with Agincourt Formapure extraction kit and amplification using the NuGEN Ovation FFPE WTA kit and labeling with the Encore Biotin Module. Data analysis utilized Partek and Genetrix software. Results: All PPB cases and 7 of 21 ERMS cases were &lt; 4 years old. 20 transcripts (10 annotated, 10 non-coding RNAs) were significantly differentially expressed in ERMS when compared to PPB patients. Insulin-like growth factor 2 (IGF2) was uniformly overexpressed in ERMS (19/21 &gt; 200) but was expressed at low levels in PPB (p&lt;0.001). 2 ERMS cases which had low level IGF2 expression were &lt; 4 years of age. Expression in the other 5 ERMS aged &lt;4 years was similar to ERMS overall (range, 500-2,000). No other differences between the two approached this degree of significance, despite a common rhabdomyogenic phenotype in the sarcomatous areas of PPB. Conclusions: We conclude that PPB is a distinct entity from most ERMS, and is not driven by IGF2 signaling. Rare cases of ERMS in the very young are more similar to PPB than common ERMS. This observation is highly significant, as IGF2 is known to drive growth in ERMS, generally related to demethylation secondary to LOH of 11p.

Gliosarcoma with osseous tissue: an occasional metaplastic component

Glioosarcomas represent a rare entity of intrinsic CNS neoplasms consisting of glial and sarcomatous elements; they account for 2% of glioblastomas. There have been few reports of metaplastic osseous transformation in gliosarcomas. Here we report a rare case of gliosarcoma with metaplastic osteoid in a 57-year-old male patient. Magnetic resonance imaging revealed a large solid cystic heterogeneous mass lesion in the left temporal lobe with peri-tumoral oedema and areas of calcification. Histology revealed a grade IV tumour with neoplastic glial and mesenchymal components with myxoid change and areas of necrosis. The sarcomatous areas contained regions of benign osteoid formation. The histogenesis of the osseous element in gliosarcomas is not well understood, and could be a result of a metaplastic change or divergent differentiation from a common progenitor cell. The osseous tissue may be in the form of newly formed osteoid, benign bone tissue formation with lacunae and osteoblastic rimming, or unequivocally malignant tissue resembling an osteosarcoma.

Uterine heterologous malignant mixed Müllerian tumor in a dwarf rabbit (Oryctolagus cuniculus)

Malignant mixed Müllerian tumor (MMMT) is a rare neoplasm of the female genital system. A case of MMMT in the uterus of an 8-year-old female dwarf rabbit, which died with clinical signs associated with severe acute dyspnea and anorexia, is described. At necropsy, an oval, firm tumor was found in each of the 2 uterine horns. Numerous metastases were scattered throughout the mediastinum, thoracic diaphragm, and all pulmonary lobes. Microscopically, the tumors consisted of a poorly demarcated, unencapsulated neoplasm, composed of closely associated carcinomatous and sarcomatous components and areas of osteosarcomatous differentiation. Metastases were composed entirely of the sarcomatous component with osteosarcomatous differentiation. Immunohistochemically, the neoplastic epithelial component was positive for cytokeratin and negative for α-smooth muscle actin (α-SMA), vimentin, and desmin. The sarcomatous component was diffusely and strongly positive for vimentin, focally positive for α-SMA (<20% of cells positive), and negative for desmin. The neoplasm was diagnosed as a heterologous MMMT with metastases to the lung, mediastinum, and thoracic diaphragm.

Adrenocortical neoplasia: evolving concepts in tumorigenesis with an emphasis on adrenal cortical carcinoma variants.

Adrenocortical carcinoma (ACC) is a rare, heterogeneous malignancy with a poor prognosis. According to WHO classification 2004, ACC variants include oncocytic ACCs, myxoid ACCs and ACCs with sarcomatous areas. Herein, we provide a comprehensive review of these rare subtypes of adrenocortical malignancy and emphasize their clinicopathological features with the aim of elucidating aspects of diagnostic categorization, differential diagnostics and biological behavior. The issue of current terminology, applied to biphasic tumors with pleomorphic, sarcomatous or sarcomatoid elements arising in adrenal cortex, is also discussed. We additionally present emerging evidence concerning the adrenal cortical tumorigenesis and the putative adenoma–carcinoma sequence as well.

Metaplastic breast carcinoma with extensive osseous differentiation: A report of two cases and review of the literature

Invasive breast cancer with osseous metaplasia is rare. Here we report two cases of metaplastic breast carcinoma with extensive osseous differentiation. Case 1: The patient was a 60-year-old woman with a right breast tumor, about 4 cm in diameter. Mammogram and ultrasound presented an irregular-shaped mass suspected for malignancy. Core needle biopsy confirmed invasive carcinoma and the patient underwent a modified radical mastectomy. Case 2: The patient was a 48-year-old woman with a left breast tumor, about 3 cm in diameter. Mammogram demonstrated a well-circumscribed mass with extensive dense calcifications. Frozen section biopsy confirmed invasive carcinoma and a modified radical mastectomy was performed. The two patients had no metastatic carcinoma in the axillary lymph nodes and remained free of recurrence and systemic metastases in a 13- and 4-month follow-up period, respectively. Histopathologically, patient 1 had an adenocarcinoma with prominent sarcomatous (osteosarcomatous) differentiation with intervening spindle cells. The sarcomatous areas showed high nuclear atypia, pleomorphism and a high Ki-67 index. In Case 2, the neoplasm consisted of invasive ductal carcinoma of no special type with an osseous metaplasia component and showed a direct transition from the carcinoma to the osseous elements. The distinction between the different types of metaplastic carcinomas, specifically the distinction between benign and malignant metaplastic (osteoid) elements, should be taken into consideration.

Malignant pigmented villonodular synovitis of the temporomandibular joint with lung metastasis: a case report and review of the literature

Malignant pigmented villonodular synovitis (PVNS) is an extremely rare lesion. Approximately 30 cases of malignant PVNS have been reported to date and of these, only 1 case involved the temporomandibular joint. Owing to the rarity of well-documented cases and the heterogeneous histologic features of this group of tumors, there has been some confusion regarding its diagnosis. The heterogeneous features of the sarcomatous areas contain fibrosarcomatous, myxosarcomatous, malignant fibrous histiocytomalike or giant cell tumorlike patterns. However, despite the absence of frank sarcomatous change in the histopathogy of PVNS, there have been 3 reported cases of metastatic lesions in the lung or lymph nodes. Here we present an additional case of clinically malignant PVNS with pulmonary metastasis after recurrence. A 29-year-old man presented in our hospital with a recurrent swelling and pain in the right preauricular area, where benign tumor had been previously resected. MRI demonstrated a large mass with a low signal intensity that seemed to demonstrate a ferromagnetic effect. Surgical resection of the lesion was performed and the diagnosis of PVNS with focal atypical cells was made. Unfortunately, at 30 months post surgery, a thoracic CT found a metastatic nodule in the left lower lobe of the lung.

A case of secondary malignant giant-cell tumor of bone with p53 mutation after long-term follow-up

A 46-year-old man was admitted to the hospital with a recurrent giant-cell tumor of the distal femur. This was his fourth recurrence, and it had occurred 16 years after his last treatment. The resected recurrent tumor was histologically determined to be a conventional giant-cell tumor. However, a single lung metastatic lesion and local recurrence were noticed 6 months after the resection, both of which were surgically excised. The lung lesion was histologically determined to be an implantation of giant-cell tumor, whereas the local recurrent lesion contained a clearly separated fibrosarcomatous area within the conventional giant-cell tumor. Immunohistochemistry showed diffuse and strong p53 expression in the fibrosarcomatous area. Direct sequencing revealed a p53 mutation in the sarcomatous area and a recessive mutant signal in the conventional area. The lung lesion also contained the same p53 mutation. Identification of the p53 mutation may help in diagnosing potential malignant transformation of giant-cell tumor.

Tumeur germinale mixte de l’ovaire avec composante rhabdomyosarcomateuse. À propos d’un cas

Malignant germ cell tumors of the ovary are rare representing 3% of all ovarian neoplasms. Hence, they are the most common ovarian malignancy in girls and young women and account for approximately two-thirds of the ovarian cancers that occur in the first two decades of life. Germ cell tumors constitute a heterogeneous group of tumors and are often mixed associating at least two different tumoral components. Exceptionally, sarcomatous areas can be found. We present a case of a 15-year old girl admitted for a voluminous left ovarian mass revealed by pelvic pain. Pathological examination of the dissected material revealed the tumor to be a mixed germ cell tumor (immature teratoma and yolk sac tumor) with rhabdomyosarcomatous component of embryonal type. Clinico-pathological characteristics of such ovarian tumors will be discussed with emphasis on diagnostic difficulties.

Cellular Angiofibroma With Atypia or Sarcomatous Transformation: Clinicopathologic Analysis of 13 Cases

Cellular angiofibroma is a mesenchymal neoplasm that is characterized by a bland spindle cell component, morphologically reminiscent of spindle cell lipoma, and thick-walled vessels. The tumor occurs equally in men and women and usually arises in the inguino-scrotal or vulvovaginal regions. An earlier study of 51 cases from our group showed that the tumor follows a benign course without any tendency for recurrence. In 1 case, an intralesional microscopic nodule of pleomorphic liposarcoma was observed. The biologic significance of atypia or sarcomatous transformation in cellular angiofibroma remains uncertain. In this study, we characterized clinicopathologic features in 13 cases of cellular angiofibroma with morphologic atypia or sarcomatous transformation. Thirteen cases with atypia or sarcomatous transformation among 154 usual cellular angiofibromas identified between 1993 and 2009 were retrieved from consultation files. There were 12 females and 1 male ranging in age from 39 to 71 years (median age, 46 y). Tumor size ranged from 1.2 to 7.5 cm. In 11 cases, the tumors occurred in the vulva. One case each occurred in the paratesticular and hip regions. Most tumors were located in subcutaneous tissue. There were 4 cases of cellular angiofibroma with atypia. Three showed severely atypical cells as scattered foci within the cellular angiofibroma. One case showed a discrete nodule of atypical cells. There were 9 cases of cellular angiofibroma with morphologic features of sarcomatous transformation. In each case, abrupt transition to a discrete sarcomatous component was seen. Of these 9 cases, the sarcomatous component in 2 cases showed features of pleomorphic liposarcoma with multivacuolated lipoblasts readily identified. Three of these 9 cases showed discrete nodule(s) closely resembling atypical lipomatous tumor within usual cellular angiofibroma. In the remaining 4 cases, the sarcomatous component was composed of pleomorphic spindle cells arranged in various patterns. By immunohistochemistry, atypical cells and sarcomatous areas showed either multifocal or more diffuse p16 expression compared with either scattered or negative expression in the conventional cellular angiofibroma. The 3 cases with atypical lipomatous tumor-like areas were negative for MDM-2 and CDK4. Follow-up information was available for 7 patients (range from 2 to 75 mo; median: 14 mo). Six patients did not develop recurrence or metastasis. One patient died of metastatic carcinoma of unknown primary site 27 months after the diagnosis of cellular angiofibroma with sarcomatous transformation. Cellular angiofibroma with atypia or morphologic sarcomatous transformation occurs predominantly in the subcutaneous tissue of the vulva and, as yet, shows no evident tendency to recur based on limited clinical follow-up available for 7 cases. The sarcomatous component can show variable features including atypical lipomatous tumor, pleomorphic liposarcoma, and pleomorphic sarcoma NOS. Overexpression of p16 in the atypical cells and sarcomatous component suggests a possible underlying molecular mechanism.

A Rare Tumour of the Breast: Carcinosarcoma

Carcinosarcoma of the breast, also known as metaplastic carcinoma, is rare with very few cases reported in the literature. A 46-year old female patient presented with a mass in her left breast. Physical examination, ultrasonography and mammography findings were consistent with malignancy. The mass was totally removed. Histopathological examination revealed carcinosarcoma of the breast. Histologic grade of the tumour was III. Ki67 proliferation index was found 40% positive. Tumour cells were positive for p53 (70% positive), c-erb-B2 (5% positive), pancytokeratin and EMA in carcinomatous areas, and vimentin in sarcomatous areas. There was no metastasis in axillary lymph node and distant metastasis. The patient is receiving chemotherapy and is under follow-up in the 54th month. Along with a review of the literature, we present the information regarding the clinical and histological findings and treatment of the patient who was operated due to breast carcinosarcoma.KeywordsBreast; Carcinoma; Carcinosarcoma

Carcinosarcoma of the breast: report of a case and review of the literature

Carcinosarcoma (CS) of the breast is a rare, poorly differentiated, malignant tumor which represents less than 0.1% of all breast cancers. It is strictly defined as a mixed, biphasic neoplasm consisting of a carcinomatous component combined with a malignant nonepithelial element of mesenchymal origin. We present a female patient with breast CS. Relevant literature is briefly reviewed. A 65-year-old-woman was admitted for the management of a palpable mass of the left breast. Mammography depicted a high-density mass with marginal irregularity and pleomorphic calcification. Subsequent excisional biopsy revealed a biphasic metaplastic breast carcinoma, and the patient underwent a left-modified radical mastectomy. The final histopathologic diagnosis was defined as a metaplastic breast carcinoma of CS type, with a squamous cell epithelial component of intermediate and mainly low-grade differentiation. Recent case series describe CS as an uncommon lesion demonstrating an intimate admixture of adenocarcinoma and sarcoma. Current data represent further evidence of the dedifferentiation theory in the origin of CS as it runs a very aggressive course and bears an ominous prognosis. The tumor is characterized by intermingled carcinomatous and sarcomatous areas resembling leaf-like structures of phyllodes pattern. Associated cumulative 5-year survival rate is estimated at 49%.

Sarcomatoid carcinoma of the adrenal gland: A case report and review of literature

Reports about adrenocortical carcinomas (AC) mixed with sarcomatous areas are very rare. The terminology and pathogenesis of such biphasic tumors remain controversial. Herein, we report a case of sarcomatoid carcinoma of the adrenal gland in a 75-year-old woman who presented with left abdominal pain of one month's standing. The results of abdominal ultrasonography and computed tomography (CT) showed the presence of a large heterogeneous adrenal mass. A left adrenalectomy and complete splenectomy were performed. Histologically, the neoplasm showed areas of adrenocortical carcinoma and areas of sarcomatoid spindle cell proliferation. When examined immunohistochemically, the carcinomatous cells stained positively for S-100 protein, Melan-A protein, and neuron-specific enolase (NSE), and focally for vimentin and the cytokeratin marker MNF 116. Also, the carcinomatous cells were immunoreactive to the monoclonal antibody HMB-45. The sarcomatous component expressed vimentin, as well as other smooth and skeletal muscle markers. Liver metastases appeared 3 months postoperatively. Twelve months after removal of the primary tumor, the patient died of her disease. To the best of our knowledge, only seven cases of adrenal sarcomatoid carcinoma have been reported in the medical literature. We review the reported cases according to the 2004 classification of the World Health Organization (WHO) of lung tumors, and highlight the histogenesis, diagnosis, and clinical course of this very aggressive tumor.

Aberrant nuclear beta-catenin expression in the spindle or corded cells in so-called corded and hyalinized endometrioid carcinomas. Another critical role of the unique morphological feature.

Corded and hyalinized endometrioid carcinoma (CHEC), showing spindle and/or corded (SPICO) cells often in the background of hyalinized stroma, is a rare variant of uterine endometrioid carcinomas. The aim of our study was to explore the status of cell-adhesion molecules (beta-catenin, E-cadherin) in CHECs and to survey whether immunostains for beta-catenin and p53 can help to distinguish CHECs from their morphological mimics: malignant mixed mullerian tumors (MMMTs) and uterine tumors resembling ovarian sex-cord tumors (UTROSCTs). Immunohistochemistry was performed and scored for each element as follows: 0: negative, 1+: <10% positive cells, 2+: 10-30%, 3+: >30%. The SPICO patterns were classified as spindle/fusiform; 3, corded; 1, and both; 2. SPICO components consisted of <10%: 4, 10-30%: 1, >30%: 1. Five contained squamous components. In SPICO elements of all CHECs, nuclear beta-catenin expression (score: 1+; 1, 2+; 2, 3+; 3) and complete loss of membranous expression of E-cadherin was observed. In contrast, comparable components (sarcomatous ones for eight MMMTs or sex-cord-like ones for six UTROSCTs) showed no nuclear positivity for beta-catenin. p53 expression was observed in SPICO (64.7%), sarcomatous (87.5%), and sex-cord-like (50%) components, and sarcomatous areas of most MMMTs notably showed diffuse and intense staining. Sequence analysis of PCR amplification products of exon 3 of the beta-catenin gene revealed mutation in all cases, except two lacking SPICO components represented on microdissected areas. Our results suggest that alterations in beta-catenin/E-cadherin complex play a critical role in SPICO features. Immunostain for beta-catenin and p53 is a promising approach for distinguishing CHECs from MMMTs and UTROSCTs.