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1.
N Engl J Med ; 388(9): 804-812, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36856616

RESUMEN

BACKGROUND: Immunosuppressed organ-transplant recipients have an increased incidence of, and mortality from, skin cancer. Nicotinamide (vitamin B3) enhances the repair of ultraviolet (UV) radiation-induced DNA damage, reduces the cutaneous immunosuppressive effects of UV radiation, and reduces the incidence of keratinocyte cancers (including squamous-cell and basal-cell carcinomas) and actinic keratoses among high-risk immunocompetent patients. Whether oral nicotinamide is useful for skin-cancer chemoprevention in organ-transplant recipients is unclear. METHODS: In this phase 3 trial, we randomly assigned, in a 1:1 ratio, organ-transplant recipients who had had at least two keratinocyte cancers in the past 5 years to receive 500 mg of nicotinamide or placebo twice daily for 12 months. Participants were examined for skin lesions by dermatologists at 3-month intervals for 12 months. The primary end point was the number of new keratinocyte cancers during the 12-month intervention period. Secondary end points included the numbers of squamous-cell and basal-cell carcinomas during the 12-month intervention period, the number of actinic keratoses until 6 months after randomization, safety, and quality of life. RESULTS: A total of 158 participants were enrolled, with 79 assigned to the nicotinamide group and 79 to the placebo group. The trial was stopped early owing to poor recruitment. At 12 months, there were 207 new keratinocyte cancers in the nicotinamide group and 210 in the placebo group (rate ratio, 1.0; 95% confidence interval, 0.8 to 1.3; P = 0.96). No significant between-group differences in squamous-cell and basal-cell carcinoma counts, actinic keratosis counts, or quality-of-life scores were observed. Adverse events and changes in blood or urine laboratory variables were similar in the two groups. CONCLUSIONS: In this 12-month, placebo-controlled trial, oral nicotinamide therapy did not lead to lower numbers of keratinocyte cancers or actinic keratoses in immunosuppressed solid-organ transplant recipients. (Funded by the National Health and Medical Research Council; ONTRANS Australian New Zealand Clinical Trials Registry number, ACTRN12617000599370.).


Asunto(s)
Antineoplásicos , Niacinamida , Neoplasias Cutáneas , Receptores de Trasplantes , Humanos , Australia , Carcinoma Basocelular/etiología , Carcinoma Basocelular/prevención & control , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/prevención & control , Quimioprevención , Queratosis Actínica/etiología , Queratosis Actínica/prevención & control , Niacinamida/administración & dosificación , Niacinamida/uso terapéutico , Calidad de Vida , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/prevención & control , Huésped Inmunocomprometido , Trasplante de Órganos/efectos adversos , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Rayos Ultravioleta/efectos adversos
2.
Histopathology ; 79(5): 791-800, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34080211

RESUMEN

AIMS: The diagnosis of focal nodular hyperplasia (FNH) and the interpretation of glutamine synthetase (GS) staining can be challenging on biopsies. We aimed to evaluate the reproducibility of needle biopsy diagnosis of FNH, the effect of GS immunohistochemistry on FNH diagnosis, and which histological features are most useful for the diagnosis of FNH. METHODS AND RESULTS: The study included virtual needle biopsies generated from 75 resection specimens (30 FNHs, 15 hepatocellular adenomas, 15 hepatocellular carcinomas, and 15 non-lesional liver specimens). Pathologists were reasonably accurate (83.1%) in the diagnosis of FNH with haematoxylin and eosin alone. Ductular reaction and nodularity had the highest sensitivity for a diagnosis of FNH (88.1% and 82.2%, respectively), whereas central scar was the most specific feature (90.6%). The presence of two or more of the classic histological features had 89.6% sensitivity and 86.2% specificity for a diagnosis of FNH. Diagnostic accuracy was significantly higher with the addition of a GS stain. A map-like GS staining pattern was highly specific (99.3%) for FNH. However, GS staining was interpreted as non-map-like in 14.4% of reviews of true FNH cases, and overall interobserver agreement for interpretation of the GS staining pattern was only moderate (kappa = 0.42). CONCLUSIONS: Pathologists are reasonably accurate in the diagnosis of FNH on virtual biopsies, and GS staining improves accuracy. However, a subset of FNH cases remain challenging. Steatosis and a pseudo-map-like GS staining pattern were associated with increased difficulty. Therefore, although a map-like GS staining pattern is useful for confirmation of a diagnosis, the lack of a map-like GS staining pattern on needle biopsy does not necessarily exclude a diagnosis of FNH.


Asunto(s)
Hiperplasia Nodular Focal , Glutamato-Amoníaco Ligasa/análisis , Neoplasias Hepáticas , Adenoma de Células Hepáticas/diagnóstico , Adenoma de Células Hepáticas/patología , Biomarcadores de Tumor/análisis , Biopsia con Aguja , Exactitud de los Datos , Diagnóstico Diferencial , Femenino , Hiperplasia Nodular Focal/diagnóstico , Hiperplasia Nodular Focal/patología , Humanos , Inmunohistoquímica , Hígado/patología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Masculino
3.
Photochem Photobiol Sci ; 19(2): 171-179, 2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-31942903

RESUMEN

Nicotinamide (NAM), an amide form of vitamin B3, replenishes cellular energy after ultraviolet radiation (UVR) exposure, thereby enhancing DNA repair and reducing UVR's immunosuppressive effects. NAM reduces actinic keratoses and new keratinocyte cancers in high risk individuals, but its effects on melanoma are unknown. Melanomas arising on NAM or placebo within the ONTRAC skin cancer chemoprevention trial (Oral Nicotinamide To Reduce Actinic Cancer) were examined by immunohistochemistry. The effects of NAM (50 µM, 5 mM and 20 mM) on the viability, proliferation and invasiveness of four human melanoma cell lines and on the viability and proliferation of two human melanocyte lines, with and without UV irradiation were also investigated. 50 µM NAM did not affect viability, proliferation or invasion of melanoma or melanocyte cell lines, whereas concentrations too high to be achievable in vivo reduced viability and proliferation. Nicotinamide did not enhance melanoma viability, proliferation or invasiveness in vitro, providing additional confidence in its safety for use in clinical trials in high risk patients. Peritumoral and tumour infiltrating CD4+ and CD8+ lymphocytes were significantly increased in melanomas arising on NAM compared to those arising on placebo. Given the chemopreventive activity of nicotinamide against keratinocyte cancers, its DNA repair enhancing effects in melanocytes and now its potential enhancement of tumour-infiltrating lymphocytes and lack of adverse effects on melanoma cell growth and proliferation, clinical trials of nicotinamide for melanoma chemoprevention are now indicated.


Asunto(s)
Melanoma/patología , Niacinamida/farmacología , Neoplasias Cutáneas/patología , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Melanoma/tratamiento farmacológico , Melanoma/prevención & control , Niacinamida/química , Niacinamida/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Rayos Ultravioleta
4.
N Engl J Med ; 373(17): 1618-26, 2015 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-26488693

RESUMEN

BACKGROUND: Nonmelanoma skin cancers, such as basal-cell carcinoma and squamous-cell carcinoma, are common cancers that are caused principally by ultraviolet (UV) radiation. Nicotinamide (vitamin B3) has been shown to have protective effects against damage caused by UV radiation and to reduce the rate of new premalignant actinic keratoses. METHODS: In this phase 3, double-blind, randomized, controlled trial, we randomly assigned, in a 1:1 ratio, 386 participants who had had at least two nonmelanoma skin cancers in the previous 5 years to receive 500 mg of nicotinamide twice daily or placebo for 12 months. Participants were evaluated by dermatologists at 3-month intervals for 18 months. The primary end point was the number of new nonmelanoma skin cancers (i.e., basal-cell carcinomas plus squamous-cell carcinomas) during the 12-month intervention period. Secondary end points included the number of new squamous-cell carcinomas and basal-cell carcinomas and the number of actinic keratoses during the 12-month intervention period, the number of nonmelanoma skin cancers in the 6-month postintervention period, and the safety of nicotinamide. RESULTS: At 12 months, the rate of new nonmelanoma skin cancers was lower by 23% (95% confidence interval [CI], 4 to 38) in the nicotinamide group than in the placebo group (P=0.02). Similar differences were found between the nicotinamide group and the placebo group with respect to new basal-cell carcinomas (20% [95% CI, -6 to 39] lower rate with nicotinamide, P=0.12) and new squamous-cell carcinomas (30% [95% CI, 0 to 51] lower rate, P=0.05). The number of actinic keratoses was 11% lower in the nicotinamide group than in the placebo group at 3 months (P=0.01), 14% lower at 6 months (P<0.001), 20% lower at 9 months (P<0.001), and 13% lower at 12 months (P=0.001). No noteworthy between-group differences were found with respect to the number or types of adverse events during the 12-month intervention period, and there was no evidence of benefit after nicotinamide was discontinued. CONCLUSIONS: Oral nicotinamide was safe and effective in reducing the rates of new nonmelanoma skin cancers and actinic keratoses in high-risk patients. (Funded by the National Health and Medical Research Council; ONTRAC Australian New Zealand Clinical Trials Registry number, ACTRN12612000625875.).


Asunto(s)
Carcinoma Basocelular/prevención & control , Carcinoma de Células Escamosas/prevención & control , Queratosis Actínica/prevención & control , Niacinamida/uso terapéutico , Neoplasias Cutáneas/prevención & control , Complejo Vitamínico B/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Basocelular/epidemiología , Carcinoma de Células Escamosas/epidemiología , Método Doble Ciego , Femenino , Humanos , Queratosis Actínica/epidemiología , Masculino , Persona de Mediana Edad , Niacinamida/efectos adversos , Prevención Secundaria , Neoplasias Cutáneas/epidemiología , Complejo Vitamínico B/efectos adversos
5.
Pathology ; 55(6): 800-805, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37393148

RESUMEN

Diagnosis of basal cell carcinoma (BCC) higher risk subtypes influences management strategies because of their propensity to recur locally. Subtyping is prone to inter-observer variability, and subtyping definitions are inconsistently applied. This study sought to compare the interobserver reproducibility of individual BCC subtypes using the 4th edition World Health Organization (WHO) Classification of Skin Tumours (CoST) definitions, with classification into lower and higher risk histological subtype groups. Ninety-one BCC cases were rated by seven pathologists, noting the presence of BCC subtype(s), and providing a higher or lower risk subtype grouping per case. Raters were provided with definitions as per the 4th edition WHO CoST for 10 listed BCC subtypes. Surgical specimen type was noted. Subgroup analysis was performed to exclude cases when the tumour deep front was not well visualised, or there was tangential sectioning (n = 6). Light's kappa was used to assess inter-rater reliability. From the total group (n = 91), five BCC subtypes showed a sufficient number of ratings for computing a κ statistic. From these five subtypes, superficial subtype showed substantial inter-rater agreement (κ = 0.64), and the other four subtypes showed moderate inter-rater agreement [nodular (κ = 0.45), sclerosing/morphoeic (κ = 0.45), infiltrating (κ = 0.49) and micronodular (κ = 0.57)]. Two-tiered rating into either higher or lower risk subtype showed substantial inter-rater agreement (κ = 0.72). Our results suggest a need to more precisely define BCC subtypes. We suggest reporting BCC subtype using a two-tiered risk grouping, followed by specific subtypes present. Further studies examining the inter-rater reliability of less common BCC subtypes are required.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/patología , Reproducibilidad de los Resultados , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/patología , Variaciones Dependientes del Observador
6.
Pathology ; 55(6): 760-771, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37573162

RESUMEN

While women pathologists have made up over one-third of pathologists in the Australian workforce for over 15 years and at least 50% since 2019, they are under-represented in senior leadership roles, scientific publications, grant recipients, editorial boards, key presentations, and professional awards. This is not unique to pathology and is seen in the broader medical and academic community. Barriers to gender equity and equality in pathology, medicine and academia include gender stereotypes, gender-based discrimination, structural and organisational barriers as well as broader social and cultural barriers. A diverse leadership reflective of the whole professional body and the broader community is important for optimal health outcomes. It is the responsibility and moral duty of individuals and organisations to address any gender disparities, inequities, and inequalities by monitoring, identifying, and acting on gender biases and systemic barriers that hinder appropriate levels of representation by women.


Asunto(s)
Equidad de Género , Sexismo , Femenino , Humanos , Australia , Recursos Humanos
8.
Acta Cytol ; 46(4): 718-22, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12146038

RESUMEN

BACKGROUND: Osteosarcomatous differentiation in malignant phyllodes tumors is rare. No cases of either primary or metastatic lesions were identified in the literature that were initially diagnosed on fine needle aspiration biopsy. CASE: Cytologic and histologic findings of a metastatic malignant phyllodes tumor with osteosarcomatous differentiation in a 63-year-old woman are presented. This case was diagnosed initially on fine needle aspiration biopsy and confirmed with histologic examination of the pulmonary lesion. CONCLUSION: Although rare, the differential diagnosis of metastatic phyllodes tumor should be considered in the appropriate clinical setting when examining a pleomorphic spindle cell tumor with heterologous elements on fine needle aspiration biopsy.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias Pulmonares/patología , Osteogénesis , Tumor Filoide/patología , Biopsia con Aguja , Diferenciación Celular , Femenino , Humanos , Neoplasias Pulmonares/fisiopatología , Neoplasias Pulmonares/secundario , Persona de Mediana Edad , Metástasis de la Neoplasia/patología
12.
J Neurooncol ; 87(1): 71-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18004504

RESUMEN

Methylation of the promoter region of the O ( 6 ) -methylguanine-DNA methyltransferase (MGMT) gene is known to be predictive of response to temozolomide treatment in patients with glioblastoma. Contrastingly, little is known about variation in the methylation status of the MGMT promoter after treatment or across different regions of the same tumor. About 22 samples from 10 patients who had undergone multiple resections of a glioblastoma were examined with promoter sequencing. Of these, 20 were also analyzed using Methylation Specific PCR (MSP). The methylation status of the MGMT promoter was altered in the specimens obtained pre and post treatment in 2 of 9 samples as assessed by MSP and 7 out of 10 patients as assessed by promoter sequencing. In four patients, the MGMT promoter was unmethylated at primary surgery, but displayed some methylation (32, 44, 12, and 4%) on post-treatment sampling. Alteration in MSP status from unmethylated to methylated was also observed in 2 of these 4 patients. In another patient, methylation increased from 40% on initial sampling to 68% on the second sample. The remaining two patients initially demonstrated some degree of methylation (72% and 12%); subsequent sampling showed no methylation of the MGMT promoter. To ensure variable methylation status was not due to intra-tumoral variability, three to four specimens were sampled from different regions of large glioblastomas (n = 7). Promoter sequencing revealed minimal variation in methylation in all but two sites examined. Immunohistochemistry also demonstrated minimal change in MGMT expression across the tumors. This suggests that variation in MGMT promoter methylation can occur within the same tumor after treatment, necessitating caution in clinical decision-making based on this analysis.


Asunto(s)
Metilación de ADN , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Glioblastoma/genética , Regiones Promotoras Genéticas , Proteínas Supresoras de Tumor/genética , Adulto , Anciano , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Metilación de ADN/efectos de los fármacos , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Femenino , Glioblastoma/tratamiento farmacológico , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Temozolomida
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