False-positive staining of thyroglobulin distinguished from mixed medullary and follicular thyroid carcinoma by duplex in situ hybridization.

Medullary thyroid carcinoma (MTC) may mimic mixed medullary and follicular thyroid carcinoma (MMFTC). MTC originates from para-follicular cells, while MMFTC is an uncommon tumor characterized by coexistence of follicular and para-follicular cell-derived tumor populations. A 35-year-old woman was diagnosed with MTC but showed a hot nodule in thyroid scintigraphy. The tumor included diffusely-spread follicular lesions within it, which were immunostained with thyroglobulin and calcitonin. Immunofluorescence showed the presence of several tumor cells that were double-stained with thyroglobulin and calcitonin. To clarify whether or not the tumor was MMFTC, we used duplex in situ hybridization (ISH). Thyroglobulin and calcitonin-related polypeptide alpha mRNA were not expressed together in a single cell, so we suspected false-positive staining of tumor cells with thyroglobulin. To make comparisons with other follicular lesions in MTC, we searched our hospital database. Five cases within a ten-year period had been pathologically diagnosed as MTC. All had follicular lesions in the tumor, but unlike the other case, they were peripherally localized. Dual differentiation into follicular or para-follicular tumor cells was not indicated by either immunofluorescence or duplex ISH. Compared with the case suspected to be MMFTC, there was only mild invasion of tumor cells into the follicular epithelium. The extent of follicular lesions and invasiveness of tumor cells may be associated with pseudo-staining of thyroglobulin in MTC. Duplex ISH can distinguish MTC that are stained with thyroglobulin from MMFTC.

Carcinosarcoma (adenocarcinoma, neuroendocrine carcinoma, undifferentiated carcinoma and chondrosarcoma) of the gallbladder.

We present an extremely rare case of carcinosarcoma with 4 different tumor components in an 88-year-old female. After a diagnosis of acute cholecystitis, we performed percutaneous transhepatic gallbladder drainage in the patient without success, followed by a cholecystectomy and choledocholithotomy. The mass was a 60 × 25 mm polypoid lesion of the gallbladder identified histologically as a carcinosarcoma with adenocarcinoma, neuroendocrine carcinoma, undifferentiated carcinoma and chondrosarcoma components. The biliary-type adenocarcinoma portion exhibited acinar growth patterns with columnar cells having large and markedly hyperchromatic nuclei. These tumor cells were immunohistochemically positive for MUC1 and CDX2. The neuroendocrine carcinoma, small cell type, cells were densely packed and small, with scant cytoplasm, finely granular nuclear chromatin and absence of nucleoli. The mitotic index was high. These tumor cells were immunohistochemically positive for synaptophysin, Ki-67 (index 40%), MUC1, CDX2 and c-Kit. The undifferentiated carcinoma consisted exclusively of spindle cells containing large, markedly hyperchromatic nuclei with a high mitotic index. These tumor cells were immunohistochemically positive for AE1/AE3. The chondrosarcoma was composed of blue-gray chondroid matrix and atypical chondrocytes containing large, hyperchromatic nuclei. These tumor cells were immunohistochemically positive for S100. Its attributes might be suggestive of a greater malignant potential and pathogenesis of carcinosarcoma.

Recent Updates on Neuroendocrine Tumors From the Gastrointestinal and Pancreatobiliary Tracts.

CONTEXT: -Gastrointestinal (GI) and pancreatobiliary tracts contain a variety of neuroendocrine cells that constitute a diffuse endocrine system. Neuroendocrine tumors (NETs) from these organs are heterogeneous tumors with diverse clinical behaviors. Recent improvements in the understanding of NETs from the GI and pancreatobiliary tracts have led to more-refined definitions of the clinicopathologic characteristics of these tumors. Under the 2010 World Health Organization classification scheme, NETs are classified as grade (G) 1 NETs, G2 NETs, neuroendocrine carcinomas, and mixed adenoneuroendocrine carcinomas. Histologic grades are dependent on mitotic counts and the Ki-67 labeling index. Several new issues arose after implementation of the 2010 World Health Organization classification scheme, such as issues with well-differentiated NETs with G3 Ki-67 labeling index and the evaluation of mitotic counts and Ki-67 labeling. Hereditary syndromes, including multiple endocrine neoplasia type 1 syndrome, von Hippel-Lindau syndrome, neurofibromatosis 1, and tuberous sclerosis, are related to NETs of the GI and pancreatobiliary tracts. Several prognostic markers of GI and pancreatobiliary tract NETs have been introduced, but many of them require further validation. OBJECTIVE: -To understand clinicopathologic characteristics of NETs from the GI and pancreatobiliary tracts. DATA SOURCES: -PubMed (US National Library of Medicine) reports were reviewed. CONCLUSIONS: -In this review, we briefly summarize recent developments and issues related to NETs of the GI and pancreatobiliary tracts.

Hallazgos de imagen de las masas cardíacas (parte II): tumores malignos y lesiones pseudotumorales / Imaging findings in cardiac masses (part II): malignant tumors and pseudotumors

Los tumores cardíacos malignos son menos frecuentes que los tumores benignos; pueden ser primarios y secundarios. Los secundarios o metastásicos son entre 20 y 40 veces más frecuentes que los primarios, con una incidencia estimada del 0,05%. Las lesiones pseudotumorales no neoplásicas pueden presentarse como masas cardíacas con características de imagen que pueden plantear el diagnóstico con neoplasias. El objetivo de este trabajo es presentar los tumores cardíacos malignos y las lesiones pseudotumorales haciendo hincapié en los hallazgos en TC y RM y en las características que permiten diferenciarlos de los tumores cardíacos benignos (AU)

Malignant heart tumors are less common than benign ones. They can be primary or secondary. Secondary or metastatic heart tumors are 20 to 40 times more common than primary malignant heart tumors, which have an estimated incidence of 0.05%. Non-neoplastic pseudotumors can present as cardiac masses, with imaging characteristics than can suggest the diagnosis of a tumor. The aim of this article is to describe and illustrate malignant heart tumors and pseudotumors, stressing the CT and MRI findings that make it possible to differentiate them from benign cardiac tumors (AU)

Combined papillary and mucoepidermoid carcinoma of the thyroid gland: a possible collision tumor diagnosed on fine-needle cytology. Report of a case with immunocytochemical and molecular correlations.

Fine-needle cytology (FNC) is frequently used to diagnose thyroid nodules discovered by palpation or imaging studies. Molecular tests on FNC material may increase its diagnostic accuracy. We report a case of a classic papillary thyroid carcinoma combined with a mucoepidermoid carcinoma correctly identified on FNC. The papillary component had a classic immunophenotype (CK19+, TTF1+), while the mucoepidermoid one was only focally CK19+. Point mutations (BRAF and RAS) and rearrangements (RET/PTC) of the papillary component have been also investigated on FNC samples, with resulting concurrent rearrangements of RET/PTC1 and RET/PTC3, but no point mutations. The histogenesis of combined papillary and mucoepidermoid carcinoma of the thyroid still remains partly unsettled, and further genomic studies are needed to shed some more light on this peculiar neoplasm.

Lesión linfoproliferativa del saco lagrimal: caso clínico / Lacrimal sac lymphoproliferative lesion: Case report

CASO CLÍNICO: Se presenta el caso de una mujer de 51 años con tumoración firme a nivel del canto interno del ojo derecho de 5 años de evolución. La biopsia excisional mediante dacriocistectomía estableció el diagnóstico de lesión linfoproliferativa de bajo grado (hiperplasia linfoide reactiva). DISCUSIÓN: Los tumores del saco lagrimal son muy raros, con un pico de incidencia en la quinta década de la vida. La clínica en fases iniciales es parecida a la obstrucción lagrimal por otras causas, de ahí que hasta un 40% de estos tumores no se sospechen y sean diagnosticados durante la realización de una dacriocistorrinostomía

CASE REPORT: The case is presented of a 51 year-old woman with a firm mass at the medial canthus of the right eye of five years onset. A low-grade lymphoproliferative lesion (reactive lymphoid hyperplasia) was diagnosed from an excisional biopsy. DISCUSSION: Lacrimal sac tumors are rare, with a peak incidence in the fifth decade of life. The initial clinical features are epiphora and medial canthus swelling. As it mimics nasolacrimal duct obstruction, up to 40% of these tumors are misdiagnosed until undergoing surgery

SOX-10 expression in cutaneous myoepitheliomas and mixed tumors.

BACKGROUND: SOX-10 expression can be demonstrated by immunohistochemistry in salivary gland myoepitheliomas, but its expression in cutaneous myoepitheliomas and in cutaneous mixed tumors with prominent myoepithelial cells has not been studied. METHODS: We assessed the staining pattern of SOX-10 in five cutaneous myoepitheliomas and six cutaneous mixed tumors with a prominent myoepithelial component among both the myoepithelial cells and cells lining lumens. In addition, we examined the staining of S100, microphthalmia-associated transcription factor (MiTF), keratin cocktail, HMK903, smooth muscle actin (SMA) and epithelial membrane antigen (EMA). RESULTS: SOX-10 positivity was seen in three of five (60%) cutaneous myoepitheliomas and in the myoepithelial cells of all cutaneous mixed tumors. SOX-10 expression on the cells lining the glandular structures in mixed tumors was variable. All myoepitheliomas and mixed tumors stained positively with S100 and negatively with MiTF. Pan-keratin, HMK903, SMA and EMA showed variable expression. CONCLUSIONS: SOX-10 is a relatively reliable marker for staining cutaneous myoepitheliomas. Cutaneous myoepitheliomas are notoriously difficult to diagnose, and the addition of SOX-10 to the repertoire of stains that can label this tumor is of practical utility. These results further support that cutaneous myoepitheliomas and cutaneous mixed tumors exist on a morphologic and immunophenotypic spectrum.

Clinicopathological significance of HER2/neu genetic heterogeneity in HER2/neu non-amplified invasive breast carcinomas and its concurrent axillary metastasis.

BACKGROUND: HER2/neu (HER2) is a significant prognostic marker for breast carcinomas. Recently, new guidelines defining HER2 genetic heterogeneity (GH) were published by the College of American Pathologists. AIMS: To determine the prevalence of HER2 GH as defined in primary invasive breast carcinoma, to determine its relationship with prognostic variables and to investigate its impact on concurrent axillary metastasis. METHODS: 235 consecutive infiltrating breast carcinomas were evaluated for GH (defined as presence of 5-50% of neoplastic cells with HER2/CEP17 ratio >2.2) using fluorescence in situ hybridisation. Pathological features of carcinomas with GH were compared with those lacking GH. GH was also evaluated in a subset of 37 paired primary carcinomas and its concurrent axillary nodal metastases using dual in situ hybridisation. RESULTS: HER2 GH was noted in 27% of HER2 negative breast carcinomas. These carcinomas demonstrated aggressive characteristics (larger size, higher grade and greater incidence of lymph node metastasis) in comparison with HER2 negative cases without GH. Higher levels of GH were associated with the equivocal HER2 status. GH was maintained in the concurrent lymph node metastases with some variations; however, two cases with clusters of HER2 amplified cells in the primary carcinoma showed HER2 amplification in the nodal metastasis. CONCLUSIONS: HER2 GH is present in 27% of breast carcinomas, portends an aggressive phenotype and contributes to the equivocal HER2 status. Evaluation of the HER2 status in nodal metastasis of select primary carcinomas with GH may be beneficial before treatment selection.

Mixed neuroendocrine tumor of the common bile duct.

CONTEXT: Mixed adenoendocrine tumors of the extrahepatic bile ducts are exceedingly rare and most of those who are rarely diagnosed are adenocarcinomas. Neuroendorine tumors accounts for only 0.2-2%. CASE REPORT: We report a case of mixed adenoneuroendo-carcinoma of the common bile duct in an 82-year-old male. CONCLUSION: Clinical experience suggests that the neuroendocrine component of mixed tumors behave more aggressively than the regular biliary adenocarcinoma component. This clinical behavior may have an important role in the management of this clinical entity.

[Clinicopathologic features of combined hepatic carcinoma].

OBJECTIVE: To investigate clinicopathological features of combined hepatocellular-cholangiocarcinoma (C-HCC-CC) with neuroendocrine carcinoma (NEC) differentiation and to review the literature. METHODS: The clinical data, histological manifestations and immunohistochemical staining results of two cases of C-HCC-CC were analyzed along with a review of the current literature. RESULTS: Both patients were male with an average age of 57.5 years. Both patients were positive for hepatitis B virus antigen. The tumors of both cases demonstrated the following 3 unequivocal mixed elements: (1) polygonal epithelial tumor cells growing in nests or trabeculae with positive staining for Hepatocyte and AFP, diagnostic of hepatocellular carcinoma (HCC). Cytoplasmic bile production was present in the tumor cells in one case; (2) elliptic or short spindle-shape small blue tumor cells growing in nests or organoid pattern with Syn/CgA/CD56 positivity confirming the presence of neuroendocrine carcinoma (NEC) component; (3) oval tumor cells growing in nests or glandular forms with positivity of CK19 and CK7 confirming differentiation of cholangiocarcinoma (CC). In both cases, the tumors contained at least 20% of each of HCC, NEC and CC components. CONCLUSION: C-HCC-CC with NEC is a rare form of primary malignancy of the liver with a poor prognosis.

Cutaneous mixed tumor, eccrine variant: a clinicopathologic and immunohistochemical study of 50 cases, with emphasis on unusual histopathologic features.

Mixed tumor, eccrine type, is a rare cutaneous adnexal neoplasm, mostly reported as isolated case reports. A systematic analysis of its histopathologic and immunohistochemical features has not previously been performed on a large series. The purpose of our investigation was to study a large number of cutaneous eccrine mixed tumors so as to fully characterize the entire spectrum of changes in the epithelial and stromal components, with an emphasis on unusual histopathologic features that may represent a diagnostic pitfall. This article reports a light microscopic and immunohistochemical study of 50 cases of eccrine mixed tumor, complemented by a literature review. Our study identified some unusual histopathologic features, thus extending the morphologic spectrum of this neoplasm. These included prominent cribriform areas, clear cell change, pseudorosette structures, prominent osseous metaplasia, and physaliphorous-like cells. Most of these features have not been previously recorded in eccrine mixed tumors and may represent a potential diagnostic pitfall.

A case of mixed ductal-endocrine carcinoma of the pancreas.

A 66-year-old male patient underwent a stomach-preserving pancreatoduodenectomy procedure because of a tumor located around the lower bile duct under the diagnosis of carcinoma of the lower bile duct. The tumor (3.5 × 2.5 cm) was found at the head of the pancreas and had invaded the papillae of Vater at the duodenum. Histology findings indicated both ductal adenocarcinoma and endocrine tumor. The ductal adenocarcinoma component expressed carcinoembryonic antigen, cytokeratin (CK)-19, CK-20, carbohydrate 19-9, and amylase, whereas the endocrine component, which occupied about one-third of the tumor, expressed glucagon, neuron-specific enolase, and chromogranin A. The Ki-67 labeling indices of the two components were 49.7% and 5.3%, respectively. Herein, we present this case of mixed ductal-endocrine carcinoma of the pancreas. Our findings indicate that its aggressive mass may be ascribable to the adenocarcinoma component with a high proliferative potential.

The prognoses of metaplastic breast cancer patients compared to those of triple-negative breast cancer patients.

Metaplastic breast carcinoma (MBC) is a rare, heterogeneous breast cancer characterized by admixture of adenocarcinoma with metaplastic elements, low hormone receptor expression, and poor outcomes. The authors retrospectively reviewed the medical records of 47 MBC patients and 1,346 invasive ductal carcinoma (IDC) patients. Two hundred eighteen of the IDC patients were triple-negative (TN-IDC) for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 (ER-/PR-/HER2-). Patients were surgically treated at the Samsung Medical Center between 2005 and 2009. The MBC patients presented with a larger tumor size, lower lymph node involvement, higher histological and nuclear grades, higher triple negativity (ER-/PR-/HER2-) and higher p53, CK5/6, and EGFR expressions compared with those of the IDC group. However, there were no significant differences in clinicopathological characteristics between MBC and TN-IDC. During the follow-up period (median duration of 30.3 months, range 2.6-56.3 months), seven (14.9%) MBC patients, and 98 (7.1%) IDC patients had disease recurrence. The three-year disease-free survival (DFS) rate was 78.1% in the MBC group and 91.1% in IDC group (P < 0.001). The three-year DFS rate was not significantly different between the MBC and TN-IDC groups (78.1 vs. 84.9%, P = 0.114). However, in patients with lymph node metastasis who underwent adjuvant chemotherapy, the three-year DFS rate was 44.4% in the MBC group and 72.5% in the TN-IDC group (P = 0.025). The authors found that MBC had a poorer clinical outcome than did IDC. In breast cancer patients with nodal metastasis, MBC had a poorer prognosis than did TN-IDC, despite adjuvant chemotherapy.

Primary malignant mixed müllerian tumor of the peritoneum a case report with review of the literature.

Malignant mixed Müllerian tumor is a rare malignancy of the genital tract and extremely uncommon in extragenital sites. This report describes a case of malignant mixed Müllerian tumor arising in the lower peritoneum of a 72-year-old female patient. The patient presented with ascites, lower abdominal mass and pleural effusion. The serum level of CA125 was elevated. At operation a diffuse carcinosis associated with tumor mass measuring 20 × 15 × 10 cm in the vesicouterine and Duglas' pouch were found. The uterus and the adnexa were unremarkable. Histopathology revealed a typical malignant mixed Müllerian tumor, heterologous type. The epithelial component was positive for cytokeratin 7 and vimentin whereas the mesenchymal component was positive for Vimentin, S100 and focally for CK7. The histogenesis of this tumor arising from the peritoneum is still speculative. Based on the previous reports and the immunohistochemical analysis of our case, we believe that this is a monoclonal tumor with carcinoma being the "precursor" element. Nevertheless, further molecular and genetic evidence is needed to support such a conclusion.

Canine mammary mixed tumours: immunohistochemical expressions of EGFR and HER-2.

BACKGROUND: Benign mixed tumours (BMTs) are frequently found in the mammary glands of female dogs, but the factors determining malignant transformation in these tumours are unknown. OBJECTIVE: To evaluate the expression of the oncoproteins, human epidermal growth factor receptor 2 (HER-2) and epidermal growth factor receptor (EGFR), in 46 carcinomas in BMTs (CBMTs) and to verify their possible association with the malignancy of the tumours. METHODS: Immunohistochemical expression was analysed in benign and malignant components separately, and then compared with 74 cases of BMTs. RESULTS: Among the CBMTs, positivity for HER-2 was found in the benign histological component of 4.3% (2/46), in the malignant epithelial non-invasive component of 14.8% (4/27) and in the malignant invasive epithelial component of 13.6% (6/44) of cases. Two of the 24 (8.3%) BMTs were positive for HER-2. There was no relationship between HER-2 and the tumour components. There was no significant difference between BMTs and CBMTs. Positivity for EGFR was found in the benign component of 17.4% (8/46) of the CBMTs, in the malignant epithelial non-invasive component of 40.7% (11/27%) and in the invasive epithelial malignant component of 45.4% (20/44). EGFR positivity was significantly associated with the invasive component of CBMTs. CONCLUSION: EGFR may contribute to malignant epithelial transformation of BMTs. In contrast, HER-2 overexpression may not be associated with the acquisition of a malignant epithelial phenotype.

Small cell carcinomas in gastrointestinal tract: immunohistochemical and clinicopathological features.

AIMS: To test the incidence of the expression of the immunohistochemical markers that aid diagnosis of gastrointestinal tract small cell carcinoma (GI-SmCC) and to evaluate the incidence of mixed endocrine-exocrine carcinomas in GI-SmCC. METHODS: Immunohistochemical studies of three antibodies against epithelial markers (CK8, AE1/AE3, EMA), four neuroendocrine differentiation markers (synaptophysin (Syn), neuron specific enolase (NSE), neuronal cell adhesion molecules (CD56), chromogranin A (CgA)), and a transcription factor (thyroid transcription factor 1 (TTF-1)) were performed. The incidence of non-endocrine carcinoma component was evaluated in 42 GI-SmCCs (11 in the oesophagus, 15 in the stomach, 15 in the colon, and 1 in the small intestine). RESULTS: The percentages of GI-SmCC with positive immunoreactivity were: CK8 92.9%, AE1/AE3 76.2%, EMA 71.4%, Syn 100%, NSE 100%, CD56 90.5%, CgA 61.9%, TTF-1 21.4%. The low molecular weight cytokeratin CK8 is more commonly expressed in GI-SmCC than is the expression of AE1/AE3 or EMA. Synaptophysin and NSE are expressed in all GI-SmCCs studied. Non-endocrine carcinoma components were demonstrated in 8 patients (4 in the oesophagus and 4 in the stomach). CONCLUSION: In detecting GI-SmCC, epithelial marker CK8 is more sensitive than AE1/AE3 or EMA, and neuroendocrine differentiation markers synaptophysin and NSE are the most useful markers. TTF-1 positivity is not uncommon in GI-SmCC, but cases with negative TTF-1 staining may indicate an extra-pulmonary primary. Non-endocrine carcinoma components were demonstrated in about 30% of oesophagus and stomach SmCC; the neoplasms should be diagnosed as mixed endocrine-exocrine carcinoma.

Cyclin D1 positive follicular lymphoma.

This report describes an unusual case of cyclin D1 expression by an otherwise typical follicular lymphoma, of low histological grade. BCL2-IGH and CCND1-IGH fusions were identified by interphase fluorescence in situ hybridisation.

Apocrine mixed tumor of the skin with a prominent pilomatricomal component.

Pilomatrical differentiation within an apocrine mixed tumor (AMT) when present is only focal and has not been reported to be extensive. We herein report an AMT with prominent pilomatrical differentiation. A 47-year-old male presented with a 0.7 cm lesion on the right eyebrow. Histologic sections revealed, underneath a neurofibroma, a well-circumscribed tumor composed of nodules of branching epithelial elements and occasional keratinous cysts within a myxoid and lipomatous stroma. The ductal structures appeared to be composed of two layers of basophilic cuboidal cells and exhibited decapitation secretion. In approximately 50% of the tumor, eosinophilic ghost/shadow cells associated with a foreign body giant cell reaction formed a nodule resembling a pilomatricoma. Focally, columns of matrical cells were seen giving rise to shadow cells. Cytokeratin (CK) 5/6 and CK14 labeled the epithelial component. CK7, CK19 and Ber-EP4 labeled the ductal structures. Carcinoembryonic antigen and epithelial membrane antigen highlighted the luminal surface. S100 stained the stromal cells within the myxoid matrix, adipocytes and spindle cells within the overlying neurofibroma. CK10 highlighted the corneocytes within the keratinous cysts. CK17 labeled the epithelial lining of the keratinous cyst. The presence of follicular and apocrine differentiation within our tumor reinforces the common embryologic derivation of these elements.