Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
1.
Head Neck Pathol ; 17(3): 722-730, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36928741

RESUMO

BACKGROUND: Ossifying fibroma (OF) of the craniofacial skeleton is a fibro-osseous lesion characterized by various patterns of bone formation in a cellular fibroblastic stroma. The molecular landscape of OF remains mostly unknown. There are a few known pathogenic abnormalities in OF, including HRPT2 mutations in conventional OF and SATB2 translocations in juvenile psammomatoid OF. On the other hand, conflicting reports exist regarding MDM2 gene amplification and chromosomal copy number alterations (CNA) in OF. METHODS: Surgically removed biopsies and curettage specimens from OF patients were obtained. Clinical, radiographic, and pathologic features of tumors were reviewed. Genomic DNA was extracted from formalin-fixed, paraffin-embedded blocks of tumor tissue. Capture-based DNA next-generation sequencing targeting the coding regions 529 cancer genes and select introns was performed. RESULTS: We identified 17 OF cases from 8 male and 8 female patients with mean age of 22 years (range 1-58 years). Nine case occurred in the gnathic bones and 8 in the extragnathic craniofacial bones. These cases included 3 juvenile psammomatoid OF, 6 conventional OF and 8 juvenile trabecular OF. Large-scale CNAs were present in 6 of 17 cases. Seven cases (41%) had focal amplifications including FOSB (n = 2, 11%), FOS (n = 4, 23%), COL1A1 (n = 4, 23%) and TBX3 (n = 5, 29%). Three cases (17%) had pathogenic CDC73 mutations. No cases showed focal MDM2 amplification. CONCLUSIONS: Here, we provided a comprehensive molecular characterization of OF that reveals a heterogeneous genetic profile with occasional large-scale CNAs (n = 6, 35%). FOS, FOSB, and TBX3 genes that regulate AP-1 transcriptional complex are frequently altered in OF (n = 7, 41%), chiefly in juvenile trabecular OF. These genes encode transcription factors that act as downstream effectors of the MAP kinase signaling pathway. MDM2 amplification is an exceedingly rare event in OF, if present at all, so identification of this event should continue to raise concern for low-grade gnathic osteosarcoma. In summary, our findings suggest that OF represents a heterogeneous group of tumors at the genetic level but dysregulation of the AP-1 pathway may play a role in pathogenesis of juvenile trabecular OF.


Assuntos
Neoplasias Ósseas , Fibroma Ossificante , Neoplasias Cranianas , Neoplasias de Tecidos Moles , Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Fibroma Ossificante/genética , Fibroma Ossificante/patologia , Perfil Genético , Fator de Transcrição AP-1 , Sequenciamento de Nucleotídeos em Larga Escala , Genômica
2.
J Cutan Pathol ; 50(2): 134-139, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35690998

RESUMO

BACKGROUND: Microsecretory adenocarcinoma (MSA) is a newly described salivary gland neoplasm characterized by MEF2C::SS18 fusions. MSA was previously thought to occur exclusively in salivary glands. Here, we expand the spectrum of known primary sites of this tumor by describing a series of cutaneous tumors with analogous findings. METHODS: We identified four cutaneous primary tumors with histopathologic features identical to MSA of the salivary glands. These cases were evaluated by immunohistochemistry, fluorescence in situ hybridization (FISH) for SS18 rearrangement and targeted RNA-sequencing. We also queried a pan-tumor database of advanced carcinomas for MEF2C::SS18. RESULTS: The cases occurred in men ranging from 61 to 74 years (mean, 68). They arose from the skin of the nose, chin, scalp, and external auditory canal. All included cords/microcysts of eosinophilic cells with bland oval nuclei and bluish mucin within fibromyxoid stroma. The scalp tumor also exhibited high-grade transformation (marked atypia, elevated mitotic rate, and necrosis), a feature unreported in salivary MSA. By immunohistochemistry, all cases were positive for S100. Two showed a myoepithelial component positive for p40 and smooth muscle actin or calponin. Three cases harbored MEF2C::SS18 by RNA sequencing, while one with limited tissue had SS18 rearrangement via FISH. Two patients had no evidence of recurrence or metastasis in limited follow-up (3 and 6 months). The pan-tumor database query also did not identify MEF2C::SS18 in any advanced cutaneous carcinomas. CONCLUSION: This report expands the sites that can be involved by MSA. Similar to salivary cases, MEF2C::SS18 represents a recurrent fusion in MSA of the skin. Unusual features in cutaneous cases not seen in salivary MSA include one case with high-grade transformation and two cases with a myoepithelial cell component. Identification of this fusion expands the spectrum of salivary-analog cutaneous tumors and aids in precise tumor classification.


Assuntos
Adenocarcinoma , Carcinoma , Neoplasias das Glândulas Salivares , Neoplasias Cutâneas , Humanos , Hibridização in Situ Fluorescente , Biomarcadores Tumorais/genética , Adenocarcinoma/genética , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/patologia , Carcinoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
3.
Head Neck Pathol ; 16(4): 991-997, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35546651

RESUMO

Ossifying fibroma of the craniofacial bones is a fibro-osseous lesion characterized by varied patterns of bone formation in a fibroblastic stroma. Ossifying fibroma is a putatively benign lesion with no reports of malignant transformation or metastasis. Differentiation from other fibro-osseous lesions can be challenging necessitating synthesis of clinical, radiological and pathological findings. The molecular pathogenesis of ossifying fibroma is poorly understood but recent studies have reported MDM2 gene amplification and chromosomal copy number changes in a subset of ossifying fibromas. MDM2 amplification in ossifying fibroma, if true, presents a diagnostic problem because this genetic event, at least among craniofacial fibro-osseous lesions, was previously considered specific for low-grade osteosarcoma. In the present study, we investigated the utility of MDM2 and CDK4 immunohistochemistry, and fluorescence in situ hybridization for MDM2 gene amplification, in the diagnosis of 44 craniofacial bone ossifying fibromas. Focal MDM2 and CDK4 nuclear immunoreactivity was found in 11 and 1 ossifying fibromas, respectively, but none demonstrated MDM2 amplification by fluorescence in situ hybridization. A single tumor displayed MDM2 amplification without nuclear immunoreactivity to either MDM2 or CDK4. Our data suggest that while focal MDM2 and CDK4 nuclear expression may be detected in a minority of ossifying fibromas, this expression does not correlate with MDM2 amplification. In addition, MDM2 amplification is extremely rare in ossifying fibroma so the detection of this genetic abnormality should continue to raise concern for osteosarcoma.


Assuntos
Amplificação de Genes , Proteínas Proto-Oncogênicas c-mdm2 , Humanos , Hibridização in Situ Fluorescente , Proteínas Proto-Oncogênicas c-mdm2/genética , Quinase 4 Dependente de Ciclina/genética
5.
Head Neck Pathol ; 14(1): 70-82, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31950477

RESUMO

Gnathic fibro-osseous lesions are a diverse group of disease processes which share overlapping microscopic features characterized by fibroblastic stroma with variable cellularity and a range of bone forming pathological processes leading to woven, sclerotic and cementum-like structures. Some of the lesions are unique to craniofacial location and a combination of clinical, radiological and pathological correlation is often necessary for diagnostic accuracy. Gnathic osteosarcomas are rare tumors with differences in age distribution and behavior as compared to osteosarcoma of long bones. This review will discuss the clinicopathological and radiological features of gnathic fibro-osseous lesions and osteosarcoma with updates on current genetics and molecular pathogenesis.


Assuntos
Fibroma Ossificante/patologia , Displasia Fibrosa Óssea/patologia , Osteossarcoma/patologia , Cementoma/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Osteomielite/patologia
6.
J Exp Med ; 216(2): 419-427, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30683736

RESUMO

PIK3CA is the most commonly altered oncogene in head and neck squamous cell carcinoma (HNSCC). We evaluated the impact of nonsteroidal anti-inflammatory drugs (NSAIDs) on survival in a PIK3CA-characterized cohort of 266 HNSCC patients and explored the mechanism in relevant preclinical models including patient-derived xenografts. Among subjects with PIK3CA mutations or amplification, regular NSAID use (≥6 mo) conferred markedly prolonged disease-specific survival (DSS; hazard ratio 0.23, P = 0.0032, 95% CI 0.09-0.62) and overall survival (OS; hazard ratio 0.31, P = 0.0043, 95% CI 0.14-0.69) compared with nonregular NSAID users. For PIK3CA-altered HNSCC, predicted 5-yr DSS was 72% for NSAID users and 25% for nonusers; predicted 5-yr OS was 78% for regular NSAID users and 45% for nonregular users. PIK3CA mutation predicted sensitivity to NSAIDs in preclinical models in association with increased systemic PGE2 production. These findings uncover a biologically plausible rationale to implement NSAID therapy in PIK3CA-altered HNSCC.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Carcinoma de Células Escamosas , Classe I de Fosfatidilinositol 3-Quinases , Neoplasias de Cabeça e Pescoço , Mutação , Proteínas de Neoplasias , Adulto , Idoso , Animais , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/terapia , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Intervalo Livre de Doença , Feminino , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Lancet ; 393(10166): 40-50, 2019 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-30449625

RESUMO

BACKGROUND: Patients with human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma have high survival when treated with radiotherapy plus cisplatin. Whether replacement of cisplatin with cetuximab-an antibody against the epidermal growth factor receptor-can preserve high survival and reduce treatment toxicity is unknown. We investigated whether cetuximab would maintain a high proportion of patient survival and reduce acute and late toxicity. METHODS: RTOG 1016 was a randomised, multicentre, non-inferiority trial at 182 health-care centres in the USA and Canada. Eligibility criteria included histologically confirmed HPV-positive oropharyngeal carcinoma; American Joint Committee on Cancer 7th edition clinical categories T1-T2, N2a-N3 M0 or T3-T4, N0-N3 M0; Zubrod performance status 0 or 1; age at least 18 years; and adequate bone marrow, hepatic, and renal function. We randomly assigned patients (1:1) to receive either radiotherapy plus cetuximab or radiotherapy plus cisplatin. Randomisation was balanced by using randomly permuted blocks, and patients were stratified by T category (T1-T2 vs T3-T4), N category (N0-N2a vs N2b-N3), Zubrod performance status (0 vs 1), and tobacco smoking history (≤10 pack-years vs >10 pack-years). Patients were assigned to receive either intravenous cetuximab at a loading dose of 400 mg/m2 5-7 days before radiotherapy initiation, followed by cetuximab 250 mg/m2 weekly for seven doses (total 2150 mg/m2), or cisplatin 100 mg/m2 on days 1 and 22 of radiotherapy (total 200 mg/m2). All patients received accelerated intensity-modulated radiotherapy delivered at 70 Gy in 35 fractions over 6 weeks at six fractions per week (with two fractions given on one day, at least 6 h apart). The primary endpoint was overall survival, defined as time from randomisation to death from any cause, with non-inferiority margin 1·45. Primary analysis was based on the modified intention-to-treat approach, whereby all patients meeting eligibility criteria are included. This study is registered with ClinicalTrials.gov, number NCT01302834. FINDINGS: Between June 9, 2011, and July 31, 2014, 987 patients were enrolled, of whom 849 were randomly assigned to receive radiotherapy plus cetuximab (n=425) or radiotherapy plus cisplatin (n=424). 399 patients assigned to receive cetuximab and 406 patients assigned to receive cisplatin were subsequently eligible. After median follow-up duration of 4·5 years, radiotherapy plus cetuximab did not meet the non-inferiority criteria for overall survival (hazard ratio [HR] 1·45, one-sided 95% upper CI 1·94; p=0·5056 for non-inferiority; one-sided log-rank p=0·0163). Estimated 5-year overall survival was 77·9% (95% CI 73·4-82·5) in the cetuximab group versus 84·6% (80·6-88·6) in the cisplatin group. Progression-free survival was significantly lower in the cetuximab group compared with the cisplatin group (HR 1·72, 95% CI 1·29-2·29; p=0·0002; 5-year progression-free survival 67·3%, 95% CI 62·4-72·2 vs 78·4%, 73·8-83·0), and locoregional failure was significantly higher in the cetuximab group compared with the cisplatin group (HR 2·05, 95% CI 1·35-3·10; 5-year proportions 17·3%, 95% CI 13·7-21·4 vs 9·9%, 6·9-13·6). Proportions of acute moderate to severe toxicity (77·4%, 95% CI 73·0-81·5 vs 81·7%, 77·5-85·3; p=0·1586) and late moderate to severe toxicity (16·5%, 95% CI 12·9-20·7 vs 20·4%, 16·4-24·8; p=0·1904) were similar between the cetuximab and cisplatin groups. INTERPRETATION: For patients with HPV-positive oropharyngeal carcinoma, radiotherapy plus cetuximab showed inferior overall survival and progression-free survival compared with radiotherapy plus cisplatin. Radiotherapy plus cisplatin is the standard of care for eligible patients with HPV-positive oropharyngeal carcinoma. FUNDING: National Cancer Institute USA, Eli Lilly, and The Oral Cancer Foundation.


Assuntos
Antineoplásicos/uso terapêutico , Cetuximab/uso terapêutico , Cisplatino/uso terapêutico , Neoplasias Orofaríngeas/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Cetuximab/administração & dosagem , Cetuximab/efeitos adversos , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/complicações , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Resultado do Tratamento
8.
Clin Cancer Res ; 23(12): 3072-3083, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27986750

RESUMO

Purpose: Human papillomavirus (HPV) 16 plays an etiologic role in a growing subset of head and neck squamous cell carcinomas (HNSCC), where viral expression of the E6 and E7 oncoproteins is necessary for tumor growth and maintenance. Although patients with HPV+ tumors have a more favorable prognosis, there are currently no HPV-selective therapies. Recent studies identified differential receptor tyrosine kinase (RTK) profiles in HPV+ versus HPV- tumors. One such RTK, HER3, is overexpressed and interacts with phosphoinositide-3-kinase (PI3K) in HPV+ tumors. Therefore, we investigated the role of HPV oncoproteins in regulating HER3-mediated signaling and determined whether HER3 could be a molecular target in HPV+ HNSCC.Experimental Design: HER3 was investigated as a molecular target in HPV+ HNSCC using established cell lines, patient-derived xenografts (PDX), and human tumor specimens. A mechanistic link between HPV and HER3 was examined by augmenting E6 and E7 expression levels in HNSCC cell lines. The dependency of HPV+ and HPV- HNSCC models on HER3 was evaluated with anti-HER3 siRNAs and the clinical stage anti-HER3 monoclonal antibody KTN3379.Results: HER3 was overexpressed in HPV+ HNSCC, where it was associated with worse overall survival in patients with pharyngeal cancer. Further investigation indicated that E6 and E7 regulated HER3 protein expression and downstream PI3K pathway signaling. Targeting HER3 with siRNAs or KTN3379 significantly inhibited the growth of HPV+ cell lines and PDXs.Conclusions: This study uncovers a direct relationship between HPV infection and HER3 in HNSCC and provides a rationale for the clinical evaluation of targeted HER3 therapy for the treatment of HPV+ patients. Clin Cancer Res; 23(12); 3072-83. ©2016 AACR.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Terapia de Alvo Molecular , Infecções por Papillomavirus/genética , Receptor ErbB-3/genética , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Linhagem Celular Tumoral , Elafina/genética , Regulação Neoplásica da Expressão Gênica/genética , Regulação Viral da Expressão Gênica/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/patogenicidade , Humanos , Camundongos , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/virologia , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Receptor ErbB-3/antagonistas & inibidores , Proteínas Repressoras/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Semin Cutan Med Surg ; 34(4): 159-60, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26814329
10.
J Oral Maxillofac Surg ; 70(8): 1860-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22104131

RESUMO

PURPOSE: To compare vascularity and angiogenic activity in aggressive and nonaggressive giant cell lesions (GCLs) of the jaws. MATERIALS AND METHODS: This is a retrospective study of 14 GCLs treated at the University of California, San Francisco. Immunohistochemistry was used to determine of the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), CD34, and CD31. VEGF and bFGF expression in giant cells (GCs) and surrounding mononuclear stroma was classified into 1) high immunoreactivity (>50% staining) and 2) low immunoreactivity (<50% staining). CD31- and CD34-stained vessels were counted at 200× magnification. Clinical and radiographic records were reviewed to classify lesions as aggressive or nonaggressive. RESULTS: Of the lesions, 8 were aggressive and 6 were nonaggressive. High VEGF expression was found within the GCs in 4 of 8 aggressive lesions compared with 1 of 6 nonaggressive lesions. The stroma in both groups had low staining. High staining of the GCs for bFGF was found in 6 of 8 aggressive lesions compared with 3 of 6 nonaggressive lesions. The stroma of all aggressive cases showed high expression of bFGF compared with 3 of 6 nonaggressive cases. The aggressive group had a mean of 20.1 ± 5.4 vessels/high-powered field (hpf) stained for CD31 compared with 11.5 ± 5.6 vessels/hpf in the nonaggressive group. The aggressive group had 24.6 ± 7.0 vessels/hpf stained with CD34 compared with 18.5 ± 4.0 vessels/hpf in the nonaggressive group. CONCLUSIONS: The vascularity and level of angiogenesis within aggressive GCLs are higher than those in nonaggressive lesions.


Assuntos
Granuloma de Células Gigantes/patologia , Doenças Maxilomandibulares/patologia , Adolescente , Adulto , Antígenos CD34/análise , Criança , Pré-Escolar , Corantes , Células Endoteliais/patologia , Feminino , Fator 2 de Crescimento de Fibroblastos/análise , Seguimentos , Células Gigantes/patologia , Granuloma de Células Gigantes/classificação , Humanos , Doenças Maxilomandibulares/classificação , Masculino , Doenças Mandibulares/classificação , Doenças Mandibulares/patologia , Doenças Maxilares/classificação , Doenças Maxilares/patologia , Microvasos/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Recidiva , Estudos Retrospectivos , Reabsorção da Raiz/patologia , Células Estromais/patologia , Fator A de Crescimento do Endotélio Vascular/análise , Adulto Jovem
11.
Clin Cancer Res ; 17(22): 7024-34, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22068658

RESUMO

PURPOSE: Problems in management of oral cancers or precancers include identification of patients at risk for metastasis, tumor recurrence, and second primary tumors or risk for progression of precancers (dysplasia) to cancer. Thus, the objective of this study was to clarify the role of genomic aberrations in oral cancer progression and metastasis. EXPERIMENTAL DESIGN: The spectrum of copy number alterations in oral dysplasia and squamous cell carcinomas (SCC) was determined by array comparative genomic hybridization. Associations with clinical characteristics were studied and results confirmed in an independent cohort. RESULTS: The presence of one or more of the chromosomal aberrations +3q24-qter, -8pter-p23.1, +8q12-q24.2, and +20 distinguishes a major subgroup (70%-80% of lesions, termed 3q8pq20 subtype) from the remainder (20%-30% of lesions, non-3q8pq20). The 3q8pq20 subtype is associated with chromosomal instability and differential methylation in the most chromosomally unstable tumors. The two subtypes differ significantly in clinical outcome with risk for cervical (neck) lymph node metastasis almost exclusively associated with the 3q8pq20 subtype in two independent oral SCC cohorts. CONCLUSIONS: Two subtypes of oral lesions indicative of at least two pathways for oral cancer development were distinguished that differ in chromosomal instability and risk for metastasis, suggesting that +3q,-8p, +8q, and +20 constitute a biomarker with clinical utility for identifying patients at risk for metastasis. Moreover, although increased numbers of genomic alterations can be harbingers of progression to cancer, dysplastic lesions lacking copy number changes cannot be considered benign as they are potential precursors to non-3q8pq20 locally invasive, yet not metastatic oral SCC.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Variações do Número de Cópias de DNA , Instabilidade Genômica , Neoplasias de Cabeça e Pescoço/secundário , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Estudos de Coortes , Hibridização Genômica Comparativa , Progressão da Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Risco
13.
Neoplasia ; 12(9): 708-17, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20824047

RESUMO

The Ras/mitogen-activated protein kinase (MAPK) pathway is considered to be a positive regulator of tumor initiation, progression, and maintenance. This study reports an opposite finding: we have found strong evidence that the MAPK pathway is inhibited in a subset of adenoid cystic carcinomas (ACCs) of the salivary glands. ACC tumors consistently overexpress the receptor tyrosine kinase (RTK) c-Kit, which has been considered a therapeutic target. We performed mutational analysis of the c-Kit gene (KIT in 17 cases of ACC and found that 2 cases of ACC had distinct missense mutations in KIT at both the genomic DNA and messenger RNA levels. These mutations caused G664R and R796G amino acid substitutions in the kinase domains. Surprisingly, the mutations were functionally inactive in cultured cells. We observed a significant reduction of MAPK (ERK1/2) activity in tumor cells, as assessed by immunohistochemistry. We performed further mutational analysis of the downstream effectors in the c-Kit pathway in the genes HRAS, KRAS, NRAS, BRAF, PIK3CA, and PTEN. This analysis revealed that two ACC tumors without KIT mutations had missense mutations in either KRAS or BRAF, causing S17N K-Ras and V590I B-Raf mutants, respectively. Our functional analysis showed that proteins with these mutations were also inactive in cultured cells. This is the first time that MAPK activity from the RTK signaling has been shown to be inhibited by gene mutations during tumor development. Because ACC seems to proliferate despite inactivation of the c-Kit signaling pathway, we suggest that selective inhibition of c-Kit is probably not a suitable treatment strategy for ACC.


Assuntos
Carcinoma Adenoide Cístico/genética , Sistema de Sinalização das MAP Quinases/genética , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas c-kit/genética , Neoplasias das Glândulas Salivares/genética , Adulto , Idoso , Carcinoma Adenoide Cístico/metabolismo , Carcinoma Adenoide Cístico/patologia , Estudos de Casos e Controles , Proliferação de Células , Análise Mutacional de DNA , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/fisiologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Neoplasias das Glândulas Salivares/metabolismo , Neoplasias das Glândulas Salivares/patologia , Células Tumorais Cultivadas
14.
Artigo em Inglês | MEDLINE | ID: mdl-20488732

RESUMO

OBJECTIVE: The aim of this study was to review the reported cases of solitary fibrous tumor (SFT) in the head and neck and to evaluate this tumor regarding histologic features, treatment, and recurrence. SFT has been described in many extrapleural sites, including the head and neck. Uniform overexpression of CD34 differentiates SFT from other spindle cell neoplasms. SFT is a slow-growing neoplasm that can be successfully treated by complete excision. A rare malignant counterpart has also been described. STUDY DESIGN: In this case series and review of published cases from English-language journals in the National Library of Medicine, we reviewed 142 cases of SFT reported in English-language literature and add 11 new cases. We compared the features reported in the previous publications of SFT from the head and neck with our series, including cases described as malignant or atypical SFT. RESULTS: Four out of 9 cases with positive margins recurred, whereas only 1 out of 10 cases with atypical or malignant features recurred. CONCLUSIONS: An important finding in SFT of the head and neck is that recurrence appears more related to incomplete excision than to microscopic grade.


Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Tumores Fibrosos Solitários/patologia , Fatores Etários , Feminino , Humanos , Masculino , Recidiva Local de Neoplasia/patologia , Fatores Sexuais
15.
Artigo em Inglês | MEDLINE | ID: mdl-20304686

RESUMO

OBJECTIVES: Several studies have documented the beneficial effect of second opinions in diagnostic pathology. Among disease sites, the head and neck can be a particularly problematic area for pathologists, prompting frequent second opinions. However, the effect of second opinion requests made by physician pathologists (PPs) to oral and maxillofacial pathologists (OMPs) has not been well studied and might identify disease and subsites that pose diagnostic challenges. The objectives of this study were to study the referral patterns of PPs to a referral center for oral and maxillofacial pathology and to assess changes in diagnosis following second opinion. STUDY DESIGN: We retrospectively reviewed 142 consecutive pathology consultation requests over a 2-year period. The submitted report and matched second opinion report were reviewed to extract predetermined demographic, clinical, and pathologic data. Each diagnosis was reviewed to determine if there was agreement, minor disagreement, or major disagreement between the original and the second opinion. RESULTS: The most common diagnostic categories sent for second opinion were dysplasia/carcinoma, odontogenic cysts, and odontogenic tumors. In the 135 cases where agreement could be assessed, there were a total of 46 cases (34.1%) with differences in diagnostic opinion. Minor disagreements occurred in 24 cases (17.8%) and major disagreements in 22 cases (16.3%). Importantly, major disagreements identified here would have resulted in significant differences in patient evaluation and management. CONCLUSIONS: This study supports the positive impact of second-opinion surgical pathology for lesions in the maxillofacial complex and supports the role of OMPs in subspecialty diagnostic pathology.


Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Cistos Odontogênicos/patologia , Padrões de Prática Médica/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Humanos , Variações Dependentes do Observador , Tumores Odontogênicos/patologia , Patologia/estatística & dados numéricos , Patologia Bucal/estatística & dados numéricos , Estudos Retrospectivos
16.
Artigo em Inglês | MEDLINE | ID: mdl-19880332

RESUMO

OBJECTIVE: Mantle cell lymphoma (MCL) is a rare B-cell neoplasm that has only recently been defined as a distinct entity. Because of its rarity and histologic similarities to other small cell lymphomas, the microscopic diagnosis of MCL may be challenging. This is particularly true within the oral cavity, where other lymphomas are more frequent. To date, few cases of MCL presenting within the oral cavity have been reported. STUDY DESIGN: We present 2 new cases of MCL within the oral cavity and systematically review 7 other cases of MCL reported in the English-language literature. Historical cases were reviewed, and available data regarding morphology, special stains, demographics, clinical presentation, radiographic findings, management, and outcome were extracted. Data from our present series were then compared with the earlier published literature. RESULTS: To the best of our knowledge, this is the largest reviewed series of MCL within the oral cavity, totaling 9 cases. The features of our cases, including histology, clinical presentation, and outcome, are consistent with the 7 earlier reported cases. The majority of oral MCLs occur in an older male population, and a high proportion occur on the palate. CONCLUSION: We conclude that MCL of the oral cavity is an uncommon diagnosis. Most oral MCLs occur in an elderly male population and have a possible predilection for the palate. The microscopic diagnosis can be challenging, given its similar appearance to other small cell lymphomas, requiring a comprehensive immunohistochemical panel for the accurate diagnosis. Like MCL occurring in other sites in the body, the prognosis and outcome of oral MCL appears to be poor.


Assuntos
Linfoma de Célula do Manto/patologia , Neoplasias Bucais/patologia , Neoplasias Palatinas/patologia , Fatores Etários , Idoso , Ciclina D1/análise , Diagnóstico Diferencial , Humanos , Técnicas Imunoenzimáticas , Imunofenotipagem , Masculino , Prognóstico , Fatores Sexuais
17.
Artigo em Inglês | MEDLINE | ID: mdl-19327639

RESUMO

OBJECTIVE: Activating mutations in the fibroblast growth factor receptor 3 (FGFR3) gene are responsible for several craniosynostosis and chondrodysplasia syndromes as well as some human cancers, including bladder and cervical carcinoma. Despite a high frequency in some benign skin disorders, FGFR3 mutations have not been reported in cutaneous malignancies. Actinic cheilitis (AC) is a sun-induced premalignancy affecting the lower lip that frequently progresses to squamous cell carcinoma (SCC). The objective of this study was to determine if FGFR3 gene mutations are present in AC and SCC of the lip. STUDY DESIGN: DNA was extracted and purified from microdissected, formalin-fixed, paraffin-embedded tissue sections of 20 cases of AC and SCC arising in AC. Exons 7, 15, and 17 were PCR amplified and direct sequenced. RESULTS: Four novel somatic mutations in the FGFR3 gene were identified: exon 7 mutation 742C-->T (amino acid change R248C), exon 15 mutations 1850A-->G (D617G) and 1888G-->A (V630M), and exon 17 mutation 2056G-->A (E686K). Grade of dysplasia did not correlate with presence of mutations. CONCLUSION: The frequency of FGFR3 receptor mutations suggests a functional role for the FGFR3 receptor in the development of epithelial disorders, and perhaps this change may contribute to the pathogenesis of some AC and SCC.


Assuntos
Carcinoma de Células Escamosas/genética , Queilite/genética , Neoplasias Labiais/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Queilite/etiologia , Análise Mutacional de DNA , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Luz Solar/efeitos adversos
18.
Cancer ; 115(1): 75-83, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18980290

RESUMO

BACKGROUND: Hyalinizing clear cell carcinoma (HCCC) is an uncommon malignant salivary gland tumor that was characterized only recently as a distinct entity. Because of its histologic similarity to several other primary and metastatic tumors and its purported favorable clinical outcome after local resection, it is important to recognize the features of this unusual tumor. METHODS: The authors present 8 new, fully characterized cases of HCCC and systematically reviewed 44 other cases of HCCC reported in the English language literature from 1980 to 2008. Historic cases were reviewed, and available data regarding morphology, special stains, demographics, clinical presentation, radiographic findings, management, and outcomes were extracted. Data from the current series were compared with the earlier published literature. RESULTS: To the best of the authors' knowledge, this was the largest reviewed series of HCCC and included a total of 52 cases. The findings, which included key histologic features, clinical presentation, and outcome, generally were consistent with what was reported previously. However, the current review revealed that 25% of patients reported in the literature had metastatases at initial presentation, including 10 of 44 patients who had metastases to regional lymph nodes and 1 patient who had metastasis to the lung. The authors were unable to identify any specific histologic features that would predict this behavior. CONCLUSIONS: The current results indicated that HCCC is less indolent than was believed previously; therefore, regional lymph node dissection should be considered in conjunction with wide local excision for patients with HCC.


Assuntos
Adenocarcinoma de Células Claras/diagnóstico , Adenocarcinoma de Células Claras/patologia , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica
19.
Int J Radiat Oncol Biol Phys ; 73(1): 166-72, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18805649

RESUMO

PURPOSE: Based on our demonstration of a circadian rhythm in the human oral mucosa cell cycle, with most cells in the G(1) phase in the morning and M phase at night, we hypothesized that morning radiotherapy (RT) would lead to less oral mucositis than afternoon RT. METHODS AND MATERIALS: A total of 216 patients were randomized to morning (8-10 AM) vs. afternoon (4-6 PM) RT and stratified by radiation dose, smoking status, and center. Patients receiving primary or postoperative RT alone were eligible. Oral mucositis was scored using the Radiation Therapy Oncology Group (RTOG) criteria and a validated scoring system. RESULTS: Of 205 evaluable patients, 52.9% vs. 62.4% developed RTOG Grade 3 or greater mucositis after morning vs. afternoon RT, respectively (p = 0.17). Morning RT was also associated with significantly less weight loss after 5 months (p = 0.024). In a subgroup of 111 patients treated to a dose of 66-70 Gy in 33-35 fractions, exploratory analyses revealed a significant reduction in Grade 3 or greater mucositis with morning RT (44.6% vs. 67.3%, p = 0.022) and a longer interval to the development of Grade 3 or greater mucositis (median, >7.9 vs. 5.6 weeks, p = 0.033). In 53 patients, who smoked during therapy, a significant reduction was found in Grade 3 or greater mucositis with morning RT (42.9% vs. 76%, p = 0.025). CONCLUSION: In this proof of principle study, morning RT was associated with significantly less weight loss after 5 months and an apparent reduction in oral mucositis in a subset of patients receiving >/=66 Gy and in patients who smoked during therapy.


Assuntos
Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Lesões por Radiação/epidemiologia , Radioterapia/métodos , Radioterapia/estatística & dados numéricos , Medição de Risco/métodos , Estomatite/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ritmo Circadiano , Comorbidade , Intervalo Livre de Doença , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/prevenção & controle , Estomatite/prevenção & controle , Estados Unidos/epidemiologia
20.
Neurosci Lett ; 433(2): 77-81, 2008 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-18242856

RESUMO

We investigated the cannabinoid receptor (CBr) agonists Win55,212-2 (non-selective) and AM1241 (CBr2 selective) and the peripheral receptor (CBr1) in carcinoma-induced pain using a mouse model. Tumors were induced in the hind paw of female mice by local injection of a human oral squamous cell carcinoma (SCC). Significant pain, as indicated by reduction in withdrawal thresholds in response to mechanical stimulation, began at 4 days after SCC inoculation and lasted to 18 days. Local administration of Win55,212-2 (10 mg/kg) and AM1241 (10 mg/kg) significantly elevated withdrawal thresholds, indicating an antinociceptive effect. Ipsilateral expression of CBr1 protein in L5 DRG was significantly upregulated compared to ipsilateral L4 DRG and in normal tissue. These findings support the suggestion that cannabinoids are capable of producing antinociception in carcinoma-induced pain.


Assuntos
Benzoxazinas/uso terapêutico , Canabinoides/uso terapêutico , Carcinoma/complicações , Morfolinas/uso terapêutico , Naftalenos/uso terapêutico , Neoplasias de Células Escamosas/complicações , Dor/tratamento farmacológico , Dor/etiologia , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Gânglios Espinais/metabolismo , Humanos , Camundongos , Camundongos Nus , Dor/patologia , Medição da Dor/métodos , Limiar da Dor/efeitos dos fármacos , Receptor CB1 de Canabinoide/metabolismo , Medula Espinal/patologia , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...