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1.
J Surg Oncol ; 117(2): 269-274, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28891266

RESUMO

BACKGROUND AND OBJECTIVES: We reviewed our series of anal squamous cell carcinomas (ASCC) treated over the last two decades. METHODS: ASCC patients undergoing treatment at the Leicester Royal Infirmary between 1998 and 2016 were selected. Age, gender, pathological tumor characteristics, treatment adopted, the overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS) at 5-year follow-up were recorded and calculated. RESULTS: A total of 190 ASCC were reviewed, of these 64.2% (n = 122) received primary radical chemoradiotherapy. Complete response rate was 92.6% (n = 113) and four patients with residual disease underwent a salvage APER. Twenty-eight patients experienced recurrent disease (23.0%) either systemic (n = 8), local (n = 14), or both (n = 6); six had a salvage APER. Complete follow-up data are available for 63.1% patients (77/122). Overall, the locoregional failure rate of primary chemoradiotherapy (residual + recurrent disease) was present in 29 patients (29/122; 23.8%). OS was 41.6% CSS was 69.2% and DFS 60.0% at 5 years follow-up. CONCLUSIONS: In our series of ASCC primary chemoradiotherapy had achieved significant initial complete response rates, however, long term-follow ups still present systemic and local recurrences. APR is able to treat 30% of the pelvic recurrences (6/20), the others are either associated with systemic disease or locally inoperable masses.


Assuntos
Neoplasias do Ânus/mortalidade , Carcinoma de Células Escamosas/mortalidade , Quimiorradioterapia/mortalidade , Terapia Combinada/mortalidade , Hospitais Universitários/estatística & dados numéricos , Recidiva Local de Neoplasia/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Ânus/patologia , Neoplasias do Ânus/terapia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida
2.
J Surg Oncol ; 114(5): 642-648, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27383398

RESUMO

BACKGROUND AND OBJECTIVES: We have reviewed our series of rectal cancer patients with circumferential resection margin involvement (R1) with particular regard to survival and prognostic factors. METHODS: R1 rectal cancer patients undergoing surgery at the Leicester Royal Infirmary between 1998 and 2008. Age, gender, radiological, and pathological tumor characteristics, neoadjuvant and adjuvant therapies were examined as prognostic factors on the overall survival (OS) and disease-free survival (DFS) at 5-year follow-up. RESULTS: A total of 885 rectal cancers were reviewed. Six hundred ninety-nine patients underwent a mesorectal excision and 71 of them were R1 resections (12.9%). OS was 43.7% (CI95% 33.5-53.8%; median survival 39 months). DFS was 57.4% (CI95% 43.0-71.8%; median survival 31 months). Pelvic recurrence rate occurred in 16 patients (26.2%, CI95% 16.5-36.0%), systemic recurrence rate in 23 patients (37.7%, CI95% 25.5-49.9%). At Cox-regression LNR and adjuvant chemotherapy were associated with both OS and DFS. No significant association was found between OS or DFS and adjuvant radiotherapy. CONCLUSIONS: In our series of R1 patients, the rates of local recurrence and OS at 5 years were 26.2% and 43.7%, respectively. Factors influencing systemic recurrences (LNR, adjuvant chemotherapy) are more associated with OS and DFS than those potentially affecting locoregional recurrences (adjuvant radiotherapy). J. Surg. Oncol. 2016;114:642-648. © 2016 Wiley Periodicals, Inc.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/terapia , Margens de Excisão , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Retais/mortalidade , Neoplasias Retais/terapia , Adenocarcinoma/patologia , Idoso , Quimiorradioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Retais/patologia , Estudos Retrospectivos , Resultado do Tratamento
3.
J Surg Oncol ; 114(1): 86-90, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27076410

RESUMO

BACKGROUND: Prone extralevator abdominoperineal excision of the rectum (ELAPE) has been introduced to improve the circumferential resection margins (CRM) compared with traditional APER. OBJECTIVE: We present short-term results achieved with prone ELAPE preceded by neoadjuvant chemoradiotherapy during the last 5 years of activity. DESIGN: A retrospective review was conducted. SETTINGS AND PATIENTS: Prone ELAPE operations performed between September 2010 and August 2014 at Leicester Royal Infirmary preceded by neoadjuvant chemoradiotherapy. INTERVENTIONS AND MAIN OUTCOME MEASURES: Data regarding demographics, staging, neoadjuvant therapies, intraoperative perforations, and perineal complications were collected. RESULTS: Seventy-two patients were included. Pretreatment radiological T4 were 25.0%, histological T4 2.8%. Intraoperative perforations occurred in 2.8%, CRM was involved in 11.1%. Perineal complications consisted of superficial wound infections (20.8%), full thickness dehiscences (16.7%), hematomas (9.7%), pelvic collections (6.9%), and perineal hernias (5.6%). CONCLUSIONS: In our experience, prone ELAPE preceded by long-course chemoradiotherapy has been successfully used in the last 5 years to resect low rectal tumors. Perineal wound complications rates are similar to those presented in series using direct perineal closures. J. Surg. Oncol. 2016;114:86-90. © 2016 Wiley Periodicals, Inc.


Assuntos
Adenocarcinoma/terapia , Quimiorradioterapia Adjuvante , Margens de Excisão , Terapia Neoadjuvante , Complicações Pós-Operatórias/epidemiologia , Neoplasias Retais/terapia , Reto/cirurgia , Abdome/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Períneo/patologia , Períneo/cirurgia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Resultado do Tratamento
4.
World J Gastroenterol ; 22(2): 467-70, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26811600

RESUMO

Complete response to chemoradiotherapy for rectal cancer is becoming a common clinical entity. Techniques to diagnose complete response and how to survey these patients without operative intervention are still unclear. We review the most recent evidence. Barriers to firm conclusions regarding this are heterogeneity of diagnostic definitions, differing surveillance protocols, and a lack of randomised studies.


Assuntos
Neoplasias Retais/radioterapia , Humanos , Valor Preditivo dos Testes , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Indução de Remissão , Resultado do Tratamento
5.
World J Surg Oncol ; 13: 331, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26637411

RESUMO

BACKGROUND: The aims of the study were to determine the radiological leak rate in those patients who had undergone a resection for left-sided colorectal cancer and to see if the presence of a leak can be related with the postoperative clinical period. We also aimed to identify any common factors between patients with leak. METHODS: A retrospective analysis of prospectively collected data of all patients who underwent a left-sided colorectal cancer resection with formation of a defunctioning ileostomy was undertaken. Between 2005 and 2010, 418 such patients were identified. RESULTS: A water-soluble contrast enema was performed in 339 patients (81.1 %). Of these, 24 (7.1 %) were reported to show an anastomotic leak. Data for these 24 patients is presented in this study. Twenty-three (95.8 %) of the leaks occurred in patients who had undergone an anterior resection; 95.8 % of the patients with a leak were male. Fifteen (62.5 %) patients underwent neo-adjuvant radiation. The mean length of stay in those patients shown to have a subsequent radiological leak was 18.8 days (median), compared with the overall unit figures of 12 days. Only 29.2 % of the patients who had a leak identified had an uncomplicated postoperative period. Overall 87.5 % of the patients had a reversal of the ileostomy. CONCLUSIONS: Radiological leakage is not uncommon. The majority of patients, who were shown to have a radiological leak in this study, were male, had undergone an anterior resection, had received neo-adjuvant radiation, had a longer initial length of stay and had postoperative complications. Water-soluble contrast enemas could be selectively used in patients with these characteristics.


Assuntos
Anastomose Cirúrgica/métodos , Fístula Anastomótica , Meios de Contraste/administração & dosagem , Enema/métodos , Ileostomia/métodos , Radiografia Abdominal/métodos , Neoplasias Retais/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Neoplasias Retais/diagnóstico por imagem , Estudos Retrospectivos
6.
Sci Transl Med ; 7(298): 298ra117, 2015 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-26223300

RESUMO

Resveratrol is widely promoted as a potential cancer chemopreventive agent, but a lack of information on the optimal dose prohibits rationally designed trials to assess efficacy. To challenge the assumption that "more is better," we compared the pharmacokinetics and activity of a dietary dose with an intake 200 times higher. The dose-response relationship for concentrations generated and the metabolite profile of [(14)C]-resveratrol in colorectal tissue of cancer patients helped us to define clinically achievable levels. In Apc(Min) mice (a model of colorectal carcinogenesis) that received a high-fat diet, the low resveratrol dose suppressed intestinal adenoma development more potently than did the higher dose. Efficacy correlated with activation of adenosine monophosphate-activated protein kinase (AMPK) and increased expression of the senescence marker p21. Nonlinear dose responses were observed for AMPK and mechanistic target of rapamycin (mTOR) signaling in mouse adenoma cells, culminating in autophagy and senescence. In human colorectal tissues exposed to low dietary concentrations of resveratrol ex vivo, we measured enhanced AMPK phosphorylation and autophagy. The expression of the cytoprotective NAD(P)H dehydrogenase, quinone 1 (NQO1) enzyme was also increased in tissues from cancer patients participating in our [(14)C]-resveratrol trial. These findings warrant a revision of developmental strategies for diet-derived agents designed to achieve cancer chemoprevention.


Assuntos
Adenoma/tratamento farmacológico , Antineoplásicos Fitogênicos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Estilbenos/administração & dosagem , Proteínas Quinases Ativadas por AMP/metabolismo , Adenoma/metabolismo , Adenoma/patologia , Animais , Autofagia/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Dieta Hiperlipídica , Relação Dose-Resposta a Droga , Humanos , Camundongos , Resveratrol , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
7.
Future Oncol ; 10(8): 1427-41, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25052753

RESUMO

Anal cancer is an uncommon cancer; however, it is rising in incidence. There is confusion regarding nomenclature and the distinction between anal canal cancer and anal margin cancer. This article discusses the modern definition, etiology and staging of anal canal and anal margin cancers. Modern chemotherapy and radiotherapy regimens are discussed, in addition to modern imaging and radiotherapy techniques. Future preventative strategies and potential novel treatments are discussed.


Assuntos
Neoplasias do Ânus/diagnóstico , Neoplasias do Ânus/terapia , Neoplasias do Ânus/epidemiologia , Neoplasias do Ânus/mortalidade , Seguimentos , Humanos , Incidência , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco
8.
J Surg Educ ; 70(2): 254-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23427973

RESUMO

BACKGROUND: Digital rectal examination (DRE) is an important skill in the investigation of rectal symptoms. This frequently performed examination is poorly taught and while students agree it is an important skill, their experience is often limited. Studies have suggested that structured teaching can improve confidence, knowledge, and ability of DRE. METHOD: Medical students from the University of Leicester attended a teaching program in DRE. It consisted of a lecture followed by objective structured clinical examination stations. These stations included the teaching of communication skills, utilized interactive scenarios, and DRE training with mannequins. Students were asked to complete an evaluation questionnaire that assessed their skill level both prior to and following the workshop. RESULTS: A total of 377 students completed the workshop and all completed our questionnaire; 228 students (63.5%) had not previously performed a DRE. Before the workshop, 55% (199/360) were not confident in performing a DRE at all. Following the workshop, 19% (68/358) of students felt confident to perform a DRE independently, and the majority, 68% (223/358) felt confident to perform a DRE on a patient under supervision. The mean score following the workshop was 4.87, improving from 2.22 before the workshop. A Student t-test showed this improvement was statistically significant (p < 0.0001, 95% CI 2.65-2.64). CONCLUSIONS: The overwhelming feedback to our program is extremely favorable and demonstrates that medical students clearly benefit from a structured, interactive, and hands-on educational workshop in DRE.


Assuntos
Exame Retal Digital , Educação Médica/métodos , Estudantes de Medicina , Competência Clínica , Inquéritos e Questionários
9.
Cancer Prev Res (Phila) ; 6(2): 119-28, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23233733

RESUMO

Curcumin, the main constituent of turmeric, is suspected to possess cancer chemopreventive properties. Pharmacokinetic and pharmacodynamic parameters have been reported, but few data exist describing whether methodologies are suitably robust for curcuminoid detection in colonic biopsy specimens. Information on the acceptability of prolonged administration of daily curcumin is not available. This is of vital importance to implement chemoprevention strategies. This study aimed to quantify levels of curcuminoids in colorectal mucosa of patients undergoing colorectal endoscopy or surgical resection and to obtain information on the acceptability and compliance with daily curcumin. Curcumin C3 complex (2.35 g) was administered to patients once daily for 14 days before endoscopic biopsy or colonic resection. Safety and tolerance were monitored. Analysis of curcuminoids in plasma, urine, and colonic mucosa was conducted by ultraperformance liquid chromatography (UPLC)-UV with characterization by liquid chromatography/tandem mass spectrometry (LC/MS-MS). Twenty-four of 26 patients commencing curcumin completed the course. Six patients reported mild gastrointestinal adverse events. Curcuminoids were detectable in nine of 24 plasma samples, 24 of 24 urine samples, and in the colonic mucosa of all 23 biopsied participants. Mean tissue levels were 48.4 µg/g (127.8 nmol/g) of parent curcuminoids. The major conjugate, curcumin glucuronide, was detectable in 29 of 35 biopsies. High levels of topical curcumin persisted in the mucosa for up to 40 hours postadministration. Sixteen participants (67%) stated that they would take curcumin long-term should it be of proven benefit. In summary, pharmacologically active levels of curcumin were recovered from colonic mucosa. The regimen used here seems safe, and patients support its use in long-term trials.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma/tratamento farmacológico , Colo/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Curcumina/farmacocinética , Aceitação pelo Paciente de Cuidados de Saúde , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/efeitos adversos , Disponibilidade Biológica , Carcinoma/metabolismo , Carcinoma/patologia , Carcinoma/urina , Colo/efeitos dos fármacos , Colo/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/urina , Curcumina/administração & dosagem , Curcumina/efeitos adversos , Feminino , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiopatologia , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Cooperação do Paciente/estatística & dados numéricos , Projetos Piloto , Fatores de Tempo
10.
Cancer Res ; 70(19): 7392-9, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20841478

RESUMO

Resveratrol is a phytochemical with chemopreventive activity in preclinical rodent models of colorectal carcinogenesis. Antiproliferation is one of the many chemopreventive modes of action it has been shown to engage in. Concentrations of resveratrol, which can be achieved in human tissues after p.o. administration, have not yet been defined. The purpose of this study was to measure concentrations of resveratrol and its metabolites in the colorectal tissue of humans who ingested resveratrol. Twenty patients with histologically confirmed colorectal cancer consumed eight daily doses of resveratrol at 0.5 or 1.0 g before surgical resection. Resveratrol was found to be well tolerated. Normal and malignant biopsy tissue samples were obtained before dosing. Parent compound plus its metabolites resveratrol-3-O-glucuronide, resveratrol-4'-O-glucuronide, resveratrol-3-O-sulfate, resveratrol-4'-O-sulfate, resveratrol sulfate glucuronide, and resveratrol disulfate were identified by high-performance liquid chromatography (HPLC) with UV or mass spectrometric detection in colorectal resection tissue. Quantitation was achieved by HPLC/UV. Cell proliferation, as reflected by Ki-67 staining, was compared in preintervention and postintervention tissue samples. Resveratrol and resveratrol-3-O-glucuronide were recovered from tissues at maximal mean concentrations of 674 and 86.0 nmol/g, respectively. Levels of resveratrol and its metabolites were consistently higher in tissues originating in the right side of the colon compared with the left. Consumption of resveratrol reduced tumor cell proliferation by 5% (P = 0.05). The results suggest that daily p.o. doses of resveratrol at 0.5 or 1.0 g produce levels in the human gastrointestinal tract of an order of magnitude sufficient to elicit anticarcinogenic effects. Resveratrol merits further clinical evaluation as a potential colorectal cancer chemopreventive agent.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Estilbenos/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/farmacocinética , Processos de Crescimento Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Terapia Combinada , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Resveratrol , Estilbenos/efeitos adversos , Estilbenos/farmacocinética
11.
Histopathology ; 57(1): 101-11, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20572881

RESUMO

AIMS: beta-Catenin is an important molecule in cancer biology. Membranous beta-catenin enhances cellular differentiation and inhibits invasion by its action on E-cadherin. The aim was to ascertain whether the cellular expression of these molecules in colorectal and oesophageal cancer specimens is associated with survival in patients with gastrointestinal cancer. METHODS AND RESULTS: Tumour samples from 149 patients undergoing resection for colorectal adenocarcinoma and 147 patients undergoing resection for oesophageal adenocarcinoma were retrospectively analysed using immunohistochemical techniques to assess beta-catenin expression. Increasing beta-catenin expression in the cytoplasm was associated with improved survival for colorectal cancer cases on both univariate (P = 0.003) and multivariate (P = 0.01) analysis. In addition, increased expression in the most recent cohort of oesophageal adenocarcinoma patients was associated with improved TNM staging (P = 0.007). Membrane expression was weakly associated with survival in colorectal cancer on univariate analysis (P = 0.09), but not on multivariate analysis (P = 0.21). Complete absence of beta-catenin expression at all three sites was associated with reduced 5-year survival in colorectal cancer. CONCLUSIONS: This is one of the largest prognostic studies of beta-catenin in gastrointestinal adenocarcinoma. It shows that low levels of cytoplasmic beta-catenin expression are associated with reduced survival in patients with colorectal cancer as well as worse TNM staging in oesophageal adenocarcinoma (a recognized surrogate end-point for survival). We believe this is the first time that this has been reported. This finding should be tested prospectively in oncological trials to validate whether the presence of cytoplasmic beta-catenin could be used as a prognostic marker for less aggressive disease.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Gastrointestinais/metabolismo , beta Catenina/metabolismo , Adenocarcinoma/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Citoplasma/metabolismo , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Neoplasias Gastrointestinais/patologia , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
12.
Cancer Prev Res (Phila) ; 2(7): 625-33, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19584076

RESUMO

Naturally occurring anthocyanins possess colorectal cancer chemopreventive properties in rodent models. We investigated whether mirtocyan, an anthocyanin-rich standardized bilberry extract, causes pharmacodynamic changes consistent with chemopreventive efficacy and generates measurable levels of anthocyanins in blood, urine, and target tissue. Twenty-five colorectal cancer patients scheduled to undergo resection of primary tumor or liver metastases received mirtocyan 1.4, 2.8, or 5.6 grams (containing 0.5-2.0 grams anthocyanins) daily for 7 days before surgery. Bilberry anthocyanins were analyzed by high performance liquid chromatography (HPLC) with visible or mass spectrometric detection. Proliferation was determined by immunohistochemistry of Ki-67 in colorectal tumor. Concentrations of insulin-like growth factor (IGF)-I were measured in plasma. Mirtocyan anthocyanins and methyl and glucuronide metabolites were identified in plasma, colorectal tissue, and urine, but not in liver. Anthocyanin concentrations in plasma and urine were roughly dose-dependent, reaching approximately 179 ng/gram in tumor tissue at the highest dose. In tumor tissue from all patients on mirtocyan, proliferation was decreased by 7% compared with preintervention values. The low dose caused a small but nonsignificant reduction in circulating IGF-I concentrations. In conclusion, repeated administration of bilberry anthocyanins exerts pharmacodynamic effects and generates concentrations of anthocyanins in humans resembling those seen in Apc(Min) mice, a model of FAP adenomas sensitive to the chemopreventive properties of anthocyanins. Studies of doses containing <0.5 gram bilberry anthocyanins are necessary to adjudge whether they may be appropriate for development as colorectal cancer chemopreventive agents.


Assuntos
Antocianinas/administração & dosagem , Anticarcinógenos/farmacologia , Neoplasias Colorretais/prevenção & controle , Vaccinium myrtillus/metabolismo , Polipose Adenomatosa do Colo/genética , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Animais , Antocianinas/farmacologia , Proliferação de Células , Neoplasias Colorretais/secundário , Feminino , Humanos , Antígeno Ki-67/biossíntese , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Metástase Neoplásica , Projetos Piloto , Extratos Vegetais/farmacologia
13.
Cancer Res ; 67(14): 6995-7002, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17638912

RESUMO

Tamoxifen is widely prescribed for the treatment of breast cancer and is also licensed in the United States for the prevention of this disease. However, tamoxifen therapy is associated with an increased occurrence of endometrial cancer in women, and there is also evidence that it may elevate the risk of colorectal cancer. The underlying mechanisms responsible for tamoxifen-induced carcinogenesis in women have not yet been elucidated, but much interest has focused on the role of DNA adduct formation. We investigated the propensity of tamoxifen to bind irreversibly to colorectal DNA when given to 10 women as a single [(14)C]-labeled therapeutic (20 mg) dose, approximately 18 h before undergoing colon resections. Using the sensitive technique of accelerator mass spectrometry, coupled with high-performance liquid chromatography separation of enzymatically digested DNA, a peak corresponding to authentic dG-N(2)-tamoxifen adduct was detected in samples from three patients, at levels ranging from 1 to 7 adducts/10(9) nucleotides. No [(14)C]-radiolabel associated with tamoxifen or its major metabolites was detected. The presence of detectable CYP3A4 protein in all colon samples suggests that this tissue has the potential to activate tamoxifen to alpha-hydroxytamoxifen, in addition to that occurring in the systemic circulation, and direct interaction of this metabolite with DNA could account for the binding observed. Although the level of tamoxifen-induced damage displayed a degree of interindividual variability, when present, it was approximately 10 to 100 times higher than that reported for other suspect human colon carcinogens such as 2-amino-1-methyl-6-phenyimidazo[4,5-b]pyridine. These findings provide a mechanistic basis through which tamoxifen could increase the incidence of colon cancers in women.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Adutos de DNA , Tamoxifeno/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/farmacologia , Radioisótopos de Carbono/química , Cromatografia Líquida de Alta Pressão , Colo/patologia , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/metabolismo , Neoplasias do Endométrio/etiologia , Neoplasias do Endométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade
14.
Clin Cancer Res ; 12(9): 2944-50, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16675592

RESUMO

Silibinin, a flavonolignan from milk thistle, has intestinal cancer chemopreventive efficacy in rodents. It is a strong antioxidant and modulates the insulin-like growth factor (IGF) system by increasing circulating levels of IGF-binding protein 3 (IGFBP-3) and decreasing levels of IGF-I. Here, the hypothesis was tested that administration of oral silibinin generates agent levels in human blood and colorectal and hepatic tissues consistent with pharmacologic activity. Patients with confirmed colorectal adenocarcinoma received silibinin formulated with phosphatidylcholine (silipide) at dosages of 360, 720, or 1,440 mg silibinin daily for 7 days. Blood and biopsy samples of normal and malignant colorectum or liver were obtained before dosing, and blood and colorectal or hepatic tissues were collected at resection surgery after the final silipide dose. Levels of silibinin were quantified by high-pressure liquid chromatography-UV, and plasma metabolites were identified by liquid chromatography-mass spectrometry. Blood levels of IGFBP-3, IGF-I, and the oxidative DNA damage pyrimidopurinone adduct of deoxyguanosine (M1dG) were determined. Repeated administration of silipide was safe and achieved levels of silibinin of 0.3 to 4 micromol/L in the plasma, 0.3 to 2.5 nmol/g tissue in the liver, and 20 to 141 nmol/g tissue in colorectal tissue. Silibinin monoglucuronide, silibinin diglucuronide, silibinin monosulfate, and silibinin glucuronide sulfate were identified in the plasma. Intervention with silipide did not affect circulating levels of IGFBP-3, IGF-I, or M1dG. The high silibinin levels achieved in the human colorectal mucosa after consumption of safe silibinin doses support its further exploration as a potential human colorectal cancer chemopreventive agent.


Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias Colorretais/prevenção & controle , Fitoterapia , Administração Oral , Idoso , Anticarcinógenos/administração & dosagem , Anticarcinógenos/sangue , Neoplasias Colorretais/sangue , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Silybum marianum , Silibina , Silimarina/administração & dosagem , Silimarina/sangue , Silimarina/uso terapêutico
15.
Clin Cancer Res ; 10(20): 6847-54, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15501961

RESUMO

Curcumin, a polyphenolic antioxidant derived from a dietary spice, exhibits anticancer activity in rodents and in humans. Its efficacy appears to be related to induction of glutathione S-transferase enzymes, inhibition of prostaglandin E(2) (PGE(2)) production, or suppression of oxidative DNA adduct (M(1)G) formation. We designed a dose-escalation study to explore the pharmacology of curcumin in humans. Fifteen patients with advanced colorectal cancer refractory to standard chemotherapies consumed capsules compatible with curcumin doses between 0.45 and 3.6 g daily for up to 4 months. Levels of curcumin and its metabolites in plasma, urine, and feces were analyzed by high-pressure liquid chromatography and mass spectrometry. Three biomarkers of the potential activity of curcumin were translated from preclinical models and measured in patient blood leukocytes: glutathione S-transferase activity, levels of M(1)G, and PGE(2) production induced ex vivo. Dose-limiting toxicity was not observed. Curcumin and its glucuronide and sulfate metabolites were detected in plasma in the 10 nmol/L range and in urine. A daily dose of 3.6 g curcumin engendered 62% and 57% decreases in inducible PGE(2) production in blood samples taken 1 hour after dose on days 1 and 29, respectively, of treatment compared with levels observed immediately predose (P < 0.05). A daily oral dose of 3.6 g of curcumin is advocated for Phase II evaluation in the prevention or treatment of cancers outside the gastrointestinal tract. PGE(2) production in blood and target tissue may indicate biological activity. Levels of curcumin and its metabolites in the urine can be used to assess general compliance.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores/sangue , Neoplasias Colorretais/tratamento farmacológico , Curcumina/uso terapêutico , Cooperação do Paciente , Administração Oral , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Curcumina/administração & dosagem , Curcumina/farmacocinética , Curcumina/farmacologia , Dinoprostona/sangue , Feminino , Glutationa Transferase/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade
16.
Ann R Coll Surg Engl ; 84(4): 260-2, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12215029

RESUMO

OBJECTIVE: To assess the effectiveness of the dedicated single-visit colorectal cancer follow-up clinic in improving postoperative surveillance. PATIENTS AND METHODS: Data of follow-up of 137 consecutive patients with colorectal cancer treated by the senior author over a 3 year period were obtained. Surveillance over three periods in time were analysed: (i) before the establishment of a protocol; (ii) following the implementation of a protocol for follow-up of colorectal cancer with liver ultrasound and colonoscopy; and (iii) following the establishment of the dedicated single-visit colorectal cancer follow-up clinic. RESULTS: The single-visit colorectal cancer follow-up clinic has reduced the mean time to the interventions (from 12.1 months to 6.0 months for the liver ultrasound and from 8.7 months to 6.4 months for the colonoscopy). In addition, the percentage of patients having their liver ultrasound within the targeted time has increased from 14% to 55%. The percentage of patients having their colonoscopy within the targeted time has also increased from 50% to 77%. The percentage who missed their liver ultrasound has been reduced from 57% to 0%. The percentage of patients who missed their colonoscopy has also been reduced from 36% to 3%. CONCLUSION: The dedicated single-visit colorectal cancer follow-up clinic improves the postoperative surveillance of patients with colorectal cancer.


Assuntos
Neoplasias Colorretais/cirurgia , Cuidados Pós-Operatórios/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Colonoscopia/métodos , Seguimentos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/secundário , Auditoria Médica , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Cuidados Pós-Operatórios/métodos , Ultrassonografia
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