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1.
Blood Adv ; 7(21): 6381-6394, 2023 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-37171397

RESUMEN

In this multi-institutional retrospective study, we examined the characteristics and outcomes of 160 patients with high-grade B-cell lymphoma, not otherwise specified (HGBL-NOS)-a rare category defined by high-grade morphologic features and lack of MYC rearrangements with BCL2 and/or BCL6 rearrangements ("double hit"). Our results show that HGBL-NOS tumors are heterogeneous: 83% of patients had a germinal center B-cell immunophenotype, 37% a dual-expressor immunophenotype (MYC and BCL2 expression), 28% MYC rearrangement, 13% BCL2 rearrangement, and 11% BCL6 rearrangement. Most patients presented with stage IV disease, a high serum lactate dehydrogenase, and other high-risk clinical factors. Most frequent first-line regimens included dose-adjusted cyclophosphamide, doxorubicin, vincristine, and etoposide, with rituximab and prednisone (DA-EPOCH-R; 43%); rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP; 33%); or other intensive chemotherapy programs. We found no significant differences in the rates of complete response (CR), progression-free survival (PFS), or overall survival (OS) between these chemotherapy regimens. CR was attained by 69% of patients. PFS at 2 years was 55.2% and OS was 68.1%. In a multivariable model, the main prognostic factors for PFS and OS were poor performance status, lactate dehydrogenase >3 × upper limit of normal, and a dual-expressor immunophenotype. Age >60 years or presence of MYC rearrangement were not prognostic, but patients with TP53 alterations had a dismal PFS. Presence of MYC rearrangement was not predictive of better PFS in patients treated with DA-EPOCH-R vs R-CHOP. Improvements in the diagnostic criteria and therapeutic approaches beyond dose-intense chemotherapy are needed to overcome the unfavorable prognosis of patients with HGBL-NOS.


Asunto(s)
Linfoma de Células B Grandes Difuso , Humanos , Persona de Mediana Edad , Rituximab/uso terapéutico , Estudios Retrospectivos , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/genética , Prednisona/uso terapéutico , Vincristina/uso terapéutico , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-myc/genética , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Etopósido , Lactato Deshidrogenasas
2.
Nature ; 440(7088): 1194-8, 2006 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-16641997

RESUMEN

After the completion of a draft human genome sequence, the International Human Genome Sequencing Consortium has proceeded to finish and annotate each of the 24 chromosomes comprising the human genome. Here we describe the sequencing and analysis of human chromosome 3, one of the largest human chromosomes. Chromosome 3 comprises just four contigs, one of which currently represents the longest unbroken stretch of finished DNA sequence known so far. The chromosome is remarkable in having the lowest rate of segmental duplication in the genome. It also includes a chemokine receptor gene cluster as well as numerous loci involved in multiple human cancers such as the gene encoding FHIT, which contains the most common constitutive fragile site in the genome, FRA3B. Using genomic sequence from chimpanzee and rhesus macaque, we were able to characterize the breakpoints defining a large pericentric inversion that occurred some time after the split of Homininae from Ponginae, and propose an evolutionary history of the inversion.


Asunto(s)
Cromosomas Humanos Par 3/genética , Animales , Secuencia de Bases , Rotura Cromosómica/genética , Inversión Cromosómica/genética , Mapeo Contig , Islas de CpG/genética , ADN Complementario/genética , Evolución Molecular , Etiquetas de Secuencia Expresada , Proyecto Genoma Humano , Humanos , Macaca mulatta/genética , Datos de Secuencia Molecular , Pan troglodytes/genética , Análisis de Secuencia de ADN , Sintenía/genética
3.
Nature ; 440(7082): 346-51, 2006 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-16541075

RESUMEN

Human chromosome 12 contains more than 1,400 coding genes and 487 loci that have been directly implicated in human disease. The q arm of chromosome 12 contains one of the largest blocks of linkage disequilibrium found in the human genome. Here we present the finished sequence of human chromosome 12, which has been finished to high quality and spans approximately 132 megabases, representing approximately 4.5% of the human genome. Alignment of the human chromosome 12 sequence across vertebrates reveals the origin of individual segments in chicken, and a unique history of rearrangement through rodent and primate lineages. The rate of base substitutions in recent evolutionary history shows an overall slowing in hominids compared with primates and rodents.


Asunto(s)
Cromosomas Humanos Par 12/genética , Animales , Composición de Base , Islas de CpG/genética , Evolución Molecular , Etiquetas de Secuencia Expresada , Genes/genética , Humanos , Desequilibrio de Ligamiento/genética , Repeticiones de Microsatélite/genética , Datos de Secuencia Molecular , Mutagénesis Insercional/genética , Pan troglodytes/genética , Análisis de Secuencia de ADN , Eliminación de Secuencia/genética , Elementos de Nucleótido Esparcido Corto/genética , Sintenía/genética
4.
Nature ; 434(7031): 325-37, 2005 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-15772651

RESUMEN

The human X chromosome has a unique biology that was shaped by its evolution as the sex chromosome shared by males and females. We have determined 99.3% of the euchromatic sequence of the X chromosome. Our analysis illustrates the autosomal origin of the mammalian sex chromosomes, the stepwise process that led to the progressive loss of recombination between X and Y, and the extent of subsequent degradation of the Y chromosome. LINE1 repeat elements cover one-third of the X chromosome, with a distribution that is consistent with their proposed role as way stations in the process of X-chromosome inactivation. We found 1,098 genes in the sequence, of which 99 encode proteins expressed in testis and in various tumour types. A disproportionately high number of mendelian diseases are documented for the X chromosome. Of this number, 168 have been explained by mutations in 113 X-linked genes, which in many cases were characterized with the aid of the DNA sequence.


Asunto(s)
Cromosomas Humanos X/genética , Evolución Molecular , Genómica , Análisis de Secuencia de ADN , Animales , Antígenos de Neoplasias/genética , Centrómero/genética , Cromosomas Humanos Y/genética , Mapeo Contig , Intercambio Genético/genética , Compensación de Dosificación (Genética) , Femenino , Ligamiento Genético/genética , Genética Médica , Humanos , Masculino , Polimorfismo de Nucleótido Simple/genética , ARN/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Homología de Secuencia de Ácido Nucleico , Testículo/metabolismo
5.
Clin Cancer Res ; 9(17): 6469-75, 2003 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-14695150

RESUMEN

PURPOSE: Patients with head and neck squamous cell carcinoma (HNSCC) often come to clinical attention with a neck mass due to metastatic spread to lymph nodes. Treatment is dictated by the subsequent determination of primary tumor site and stage. However, the primary site remains elusive in some patients even after an exhaustive examination. Human papillomavirus type 16 (HPV-16) is an important etiologic agent for HNSCCs that arise within the oropharynx but less so for tumors from nonoropharyngeal sites. Detection of HPV-16 or a surrogate marker may be useful in localizing tumor origin in patients who present with metastatic HNSCC. EXPERIMENTAL DESIGN: We performed in situ hybridization (ISH) for HPV-16 on lymph node metastases from 68 patients with HNSCC. P16 immunohistochemistry was also performed because HPV-16 integration disrupts the retinoblastoma pathway and induces an overexpression of p16. RESULTS: HPV-16 was detected in 22 of the 68 (32%) cases by ISH. When stratified by site of origin, HPV-16 was detected in 22 of 31 (71%) metastases from the oropharynx, but in none of the 37 (0%) metastases from other sites (P < 0.001; Fisher's exact). P16 expression was associated with the presence of HPV-16 by ISH: 21 of 22 HPV-16 positive tumors exhibited p16 expression, whereas only 4 of the 46 HPV-16-negative tumors were p16 positive (95% versus 9%; P < 0.001; Fisher's exact). P16 expression in the node metastases also correlated with site of tumor origin: 24 of 31 oropharyngeal tumors were p16 positive, whereas only 1 of 37 nonoropharyngeal tumors was p16 positive (77% versus 3%; P < 0.001; Fisher's exact). CONCLUSIONS: For patients with metastatic HNSCC, detection of HPV-16 is a reliable way to establish origin from the oropharynx, either directly by ISH or indirectly by immunohistochemistry for p16 overexpression.


Asunto(s)
Cuello del Útero/metabolismo , Ganglios Linfáticos/metabolismo , Papillomaviridae/metabolismo , Carcinoma de Células Escamosas/metabolismo , Cuello del Útero/virología , Femenino , Neoplasias de Cabeza y Cuello/metabolismo , Humanos , Inmunohistoquímica , Hibridación in Situ , Ganglios Linfáticos/virología , Metástasis Linfática , Metástasis de la Neoplasia
6.
Am J Surg Pathol ; 28(2): 160-7, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15043304

RESUMEN

Determining the origin of uterine adenocarcinomas can be difficult in biopsy and curettage specimens because the morphologic spectrum of endocervical and endometrial adenocarcinomas overlaps. In hysterectomy specimens, the primary site is often equivocal for tumors that involve the lower uterine segment and endocervix and lack identifiable precursor lesions. Most endocervical adenocarcinomas (ECAs) contain high-risk human papillomavirus (HPV) DNA, whereas endometrial adenocarcinomas (EMAs) rarely do. p16 is an inhibitor ofcyclin-dependent kinases, and overexpression of p16 has been observed in cervical intraepithelial lesions and invasive carcinomas associated with high-risk HPV types. We evaluated the utility of immunohistochemistry for p16 in the distinction of ECAs and EMAs. p16 expression was assessed in 24 unequivocal EMAs and 19 unequivocal ECAs and correlated with HPV DNA detection by in situ hybridization and polymerase chain reaction. These assays were then used to assist in the classification of four lower uterine segment/upper endocervical adenocarcinomas (LUS/EC-A) of equivocal origin. p16 expression was moderate-strong and diffuse in 18 ECAs (median 90% of tumor cells positive, range 90%-100%), and weak and diffuse in one. Fourteen of these were positive for HPV DNA, whereas 5 lacked detectable HPV DNA by in situ hybridization; one of these 5 was positive by polymerase chain reaction. In contrast, EMAs displayed weaker staining with patchy distribution (median 30% of tumor cells positive, range 5%-70%) and none contained HPV DNA by in situ hybridization. Two LUS/EC-As, which were positive for HPV, exhibited strong, diffuse p16 expression, consistent with endocervical origin of the tumors. The remaining 2 LUS/EC-As showed patchy p16 staining and did not contain detectable HPV DNA, consistent with the endometrial origin of the tumors. The p16 expression pattern can distinguish ECAs from EMAs. Compared with HPV DNA detection by in situ hybridization, p16 immunohistochemistry appears to be a more sensitive and easier to perform method for distinguishing ECAs from EMAs, can be used to assist in the classification of LUS/EC-As of equivocal origin, and should be evaluated for its utility in the prospective classification of uterine adenocarcinomas in curettage specimens prior to hysterectomy.


Asunto(s)
Adenocarcinoma/virología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , ADN Viral/análisis , Neoplasias Endometriales/virología , Papillomaviridae/genética , Neoplasias del Cuello Uterino/virología , Adenocarcinoma/metabolismo , Adulto , Neoplasias Endometriales/metabolismo , Femenino , Humanos , Inmunohistoquímica , Hibridación in Situ , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Neoplasias del Cuello Uterino/metabolismo
7.
Am J Surg Pathol ; 26(8): 1024-31, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12170089

RESUMEN

Sarcomatoid carcinoma of the upper respiratory tract is a phenotypically complex neoplasm that has triggered much thoughtful discussion regarding histogenic origin and morphologic classification. In particular, its putative epithelial lineage and distinction from a pseudosarcomatous reaction are sometimes questioned. Little is known about the genetic alterations underlying sarcomatoid carcinoma. Although about 45% of conventional squamous cell carcinomas of the upper respiratory tract harbor p53 mutations, the p53 status of sarcomatoid carcinomas is not well established. p53 immunohistochemical analysis using the monoclonal antibody D07 was performed on 23 sarcomatoid carcinomas of the upper respiratory tract. Twenty tumors were biphasic, having dual epithelial and spindled components. In four of these biphasic tumors, the epithelial and spindled components were separately analyzed for p53 gene mutations by sequence analysis. p53 immunohistochemistry was also performed on 19 cases of postradiation stromal atypia. Strong and diffuse p53 staining was detected in 18 (78%) of the 23 sarcomatoid carcinomas. When the spindled component was compared with its corresponding epithelial component, identical patterns of p53 protein expression were noted in 19 (95%) of the 20 biphasic tumors. Weak p53 staining was observed in one (5%) of the 19 cases of postradiation stromal atypia. In the four biphasic tumors evaluated by DNA sequence analysis, p53 status was always the same in the paired epithelial and spindle cell components. These findings help further dispel the notion that sarcomatoid carcinoma represents a reactive spindle cell proliferation (pseudosarcoma) or a collision between a carcinoma and a sarcoma (collision tumor). Instead, the epithelial and spindled components share a common pathway of tumorigenesis despite their conspicuous divergence at the phenotypic level.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias del Sistema Respiratorio/genética , Proteína p53 Supresora de Tumor/análisis , Adulto , Anciano , Carcinoma de Células Escamosas/patología , ADN/análisis , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias del Sistema Respiratorio/patología , Sarcoma/genética , Sarcoma/patología , Proteína p53 Supresora de Tumor/genética
8.
Am J Clin Pathol ; 120(5): 795-9, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14608908

RESUMEN

We determined the usefulness of immature granulocyte measurement as a predictor of infection or positive blood culture and compared the results with total WBC count and absolute neutrophil count (ANC). Blood samples from 102 infected and 69 noninfected patients were analyzed using the Sysmex XE-2100 automated blood cell counter (Sysmex, Kobe, Japan). The percentage of immature granulocytes was significantly higher in infected than in noninfected patients and in patients with positive than patients with negative blood cultures. Receiver operating characteristic curves showed that the percentage of immature granulocytes was a better predictor of infection than the WBC count and comparable to the ANC. Automated immature granulocyte measurements reflect a biologically and clinically relevant phenomenon but are not sensitive enough to be used as screening assays for prediction of infection or bacteremia. However, although infrequently encountered, a percentage of immature granulocytes of more than 3 was a very specific predictor of sepsis and might help expedite microbiologic laboratory evaluation of a subset of patients.


Asunto(s)
Granulocitos , Infecciones/sangre , Recuento de Leucocitos/instrumentación , Sepsis/sangre , Humanos , Neutrófilos
9.
Diagn Cytopathol ; 30(3): 178-81, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14986298

RESUMEN

Fine-needle aspiration of abdominal fat pad (FNAFP) is commonly employed for the diagnosis of systemic amyloidosis, a disease with highly variable clinical manifestations, often presenting difficult patient management problems. We evaluated the role of FNAFP particularly in reference to its clinical usefulness. Pathology reports and clinical histories of 91 consecutive cases of FNAFP with Congo red (CR) staining at The Johns Hopkins Hospital (1999-2000) were reviewed. Major emphases were assessment of the clinical utility of the test, correlation with concurrent or subsequent biopsies, and treatment strategies. The primary indications for FNAFP were monoclonal gammopathy (34%), cardiomyopathy (22%), renal insufficiency (20%), neuropathy (8%), plasma cell dyscrasia (6%), and other conditions (10%). Of the 91 patients who underwent FNAFP, the results were as follows; 20 cases (22%) positive; 62 cases (68%) negative; eight cases (9%) insufficient for diagnosis; and one case (1%) equivocal. Of the 20 positive cases, follow-up biopsies were performed on 11 cases, of which six were positive and five were negative for amyloid by CR. Of the 62 negative cases, follow-up biopsies were performed on 19 cases, 14 of which were negative and five positive for amyloid by CR. A follow-up biopsy on the single equivocal case was positive for amyloid by CR. Twenty-one patients positive for amyloid, based on initial or follow-up biopsies, were managed symptomatically without any specific treatment for amyloidosis. One patient, who was specifically treated for amyloidosis by melphalan and dexamethasone, died 1 wk after therapy. Three patients with multiple myeloma and amyloidosis underwent chemotherapy. We conclude that primary clinical indications for FNAFP for amyloidosis are highly variable. An FNAFP result is often not considered clinically conclusive and is followed by further invasive procedures to detect amyloid (55% of our positive and 31% of our negative FNAFP cases were rebiopsied). The estimated sensitivity and specificity of FNAFP were 75% and 92%, respectively. Overall, the reliance on the results of FNAFP depended on the degree of clinical suspicion of the treating physician. Although in the majority of cases diagnosis of amyloidosis did not alter the treatment strategies, a conclusive positive result helped in ruling out other underlying conditions as the cause of patients' symptoms.


Asunto(s)
Tejido Adiposo/patología , Amiloide/metabolismo , Amiloidosis/diagnóstico , Biopsia con Aguja Fina/métodos , Abdomen , Tejido Adiposo/química , Adulto , Anciano , Anciano de 80 o más Años , Amiloide/análisis , Amiloidosis/metabolismo , Colorantes/química , Rojo Congo/química , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
10.
Head Neck ; 25(10): 841-7, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12966508

RESUMEN

BACKGROUND: Histopathologic scrutiny of surgical pathology specimens can uncover unexpected but important pathologic processes that might not (yet) be clinically apparent. We suspect that cervical lymph nodes removed from patients with known cancers of the head and neck might occasionally harbor clinically unsuspected neoplasms. METHODS: We reviewed the pathology reports of all patients who had undergone cervical lymph node dissections at our institution between 1984 and 2001 to determine the prevalence of occult metastatic thyroid cancer and other clinically unsuspected tumors. The medical records were reviewed to obtain follow-up information when histologic examination disclosed some significant finding that was unsuspected on clinical grounds. RESULTS: Of the 1337 patients who underwent cervical lymphadenectomy during the 17-year period, 27 (2.0%) had at least one lymph node harboring an unanticipated finding that raised the concern of a clinically unsuspected neoplasm. Sixteen (1.2%) of these patients had conclusive histologic evidence of an unexpected neoplasm, including 6 patients (0.4%) with malignant lymphomas (low-grade B cell, n = 5; high-grade B cell, n = 1) and 10 patients (0.7%) with metastatic papillary thyroid carcinomas. An additional 11 patients (0.8%) had lymph nodes harboring "benign" thyroid inclusions or psammoma bodies. Four of these 11 patients underwent thyroidectomy, but thyroid cancer was not detected in the ipsilateral thyroid. Only one patient died as a consequence of the incidentally discovered neoplasm. CONCLUSIONS: To the degree that our study population is reflective of the adult population at large, at least 1% of adults harbor malignant neoplasms in their cervical lymph nodes. Although this statistic seems alarmingly high, most of these neoplasms are indolent and do not undergo unrelenting progression to clinically overt malignancies.


Asunto(s)
Escisión del Ganglio Linfático/estadística & datos numéricos , Ganglios Linfáticos/patología , Neoplasias Primarias Desconocidas/epidemiología , Neoplasias Primarias Desconocidas/patología , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Metástasis Linfática , Masculino , Maryland/epidemiología , Persona de Mediana Edad , Prevalencia , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Estados Unidos
11.
Br J Haematol ; 126(6): 785-91, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15352981

RESUMEN

Myeloid sarcoma is an extramedullary tumour that typically occurs in the setting of acute myeloid leukaemia (AML), or myeloproliferative disorders. In AML, two types of mutations in Fms-like tyrosine kinase 3 (FLT3) have been described; internal tandem duplications (ITD) and point mutations at aspartic acid residue 835 (D835). We analysed 24 myeloid sarcoma specimens from 20 patients for FLT3 ITD and D835 mutations. FLT3 ITD mutations were identified in three of 20 cases (15%); no D835 mutations were identified. The ITD inserts ranged in size from 33 to 198 base pairs (bp) and represented approximately 20-40% of the FLT3 alleles. Two cases showed discordance in FLT3 ITD mutational status. In one case, the leukaemia specimen was positive for a FLT3 ITD mutation and the myeloid sarcoma specimen was negative. In the second case, the myeloid sarcoma was positive for a FLT3 ITD mutation at diagnosis, but negative in subsequent relapse samples. Our findings suggest that small molecule inhibitors of FLT3 may be useful therapeutic agents for treatment of myeloid sarcomas-containing FLT3 mutations, however, the potential for discordance between the leukaemia and myeloid sarcoma, necessitates that the myeloid sarcoma tumour itself be analysed for FLT3 mutations.


Asunto(s)
Leucemia Mieloide/genética , Mutación , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis Mutacional de ADN/métodos , ADN de Neoplasias/genética , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/genética , Mutación Puntual , Secuencias Repetidas en Tándem/genética , Tirosina Quinasa 3 Similar a fms
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