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1.
Comput Med Imaging Graph ; 116: 102403, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38878632

RESUMEN

BACKGROUND AND OBJECTIVES: Bio-medical image segmentation models typically attempt to predict one segmentation that resembles a ground-truth structure as closely as possible. However, as medical images are not perfect representations of anatomy, obtaining this ground truth is not possible. A surrogate commonly used is to have multiple expert observers define the same structure for a dataset. When multiple observers define the same structure on the same image there can be significant differences depending on the structure, image quality/modality and the region being defined. It is often desirable to estimate this type of aleatoric uncertainty in a segmentation model to help understand the region in which the true structure is likely to be positioned. Furthermore, obtaining these datasets is resource intensive so training such models using limited data may be required. With a small dataset size, differing patient anatomy is likely not well represented causing epistemic uncertainty which should also be estimated so it can be determined for which cases the model is effective or not. METHODS: We use a 3D probabilistic U-Net to train a model from which several segmentations can be sampled to estimate the range of uncertainty seen between multiple observers. To ensure that regions where observers disagree most are emphasised in model training, we expand the Generalised Evidence Lower Bound (ELBO) with a Constrained Optimisation (GECO) loss function with an additional contour loss term to give attention to this region. Ensemble and Monte-Carlo dropout (MCDO) uncertainty quantification methods are used during inference to estimate model confidence on an unseen case. We apply our methodology to two radiotherapy clinical trial datasets, a gastric cancer trial (TOPGEAR, TROG 08.08) and a post-prostatectomy prostate cancer trial (RAVES, TROG 08.03). Each dataset contains only 10 cases each for model development to segment the clinical target volume (CTV) which was defined by multiple observers on each case. An additional 50 cases are available as a hold-out dataset for each trial which had only one observer define the CTV structure on each case. Up to 50 samples were generated using the probabilistic model for each case in the hold-out dataset. To assess performance, each manually defined structure was matched to the closest matching sampled segmentation based on commonly used metrics. RESULTS: The TOPGEAR CTV model achieved a Dice Similarity Coefficient (DSC) and Surface DSC (sDSC) of 0.7 and 0.43 respectively with the RAVES model achieving 0.75 and 0.71 respectively. Segmentation quality across cases in the hold-out datasets was variable however both the ensemble and MCDO uncertainty estimation approaches were able to accurately estimate model confidence with a p-value < 0.001 for both TOPGEAR and RAVES when comparing the DSC using the Pearson correlation coefficient. CONCLUSIONS: We demonstrated that training auto-segmentation models which can estimate aleatoric and epistemic uncertainty using limited datasets is possible. Having the model estimate prediction confidence is important to understand for which unseen cases a model is likely to be useful.

2.
Int J Radiat Oncol Biol Phys ; 117(5): 1096-1106, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37393022

RESUMEN

PURPOSE: The TOPGEAR phase 3 trial hypothesized that adding preoperative chemoradiation therapy (CRT) to perioperative chemotherapy will improve survival in patients with gastric cancer. Owing to the complexity of gastric irradiation, a comprehensive radiation therapy quality assurance (RTQA) program was implemented. Our objective is to describe the RTQA methods and outcomes. METHODS AND MATERIALS: RTQA was undertaken in real time before treatment for the first 5 patients randomized to CRT from each center. Once acceptable quality was achieved, RTQA was completed for one-third of subsequent cases. RTQA consisted of evaluating (1) clinical target volume and organ-at-risk contouring and (2) radiation therapy planning parameters. Protocol violations between high- (20+ patients enrolled) and low-volume centers were compared using the Fisher exact test. RESULTS: TOPGEAR enrolled 574 patients, of whom 286 were randomized to receive preoperative CRT and 203 (71%) were included for RTQA. Of these, 67 (33%) and 136 (67%) patients were from high- and low-volume centers, respectively. The initial RTQA pass rate was 72%. In total, 28% of cases required resubmission. In total, 200 of 203 cases (99%) passed RTQA before treatment. Cases from low-volume centers required resubmission more often (44/136 [33%] vs 13/67 [18%]; P = .078). There was no change in the proportion of cases requiring resubmission over time. Most cases requiring resubmission had multiple protocol violations. At least 1 aspect of the clinical target volume had to be adjusted in all cases. Inadequate coverage of the duodenum was most common (53% major violation, 25% minor violation). For the remaining cases, the resubmission process was triggered secondary to poor contour/plan quality. CONCLUSIONS: In a large multicenter trial, RTQA is feasible and effective in achieving high-quality treatment plans. Ongoing education should be performed to ensure consistent quality during the entire study period.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/terapia , Terapia Neoadyuvante , Estudios de Factibilidad , Garantía de la Calidad de Atención de Salud , Quimioradioterapia
3.
BMC Cancer ; 22(1): 1324, 2022 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-36528772

RESUMEN

BACKGROUND: Oesophageal and gastrooesophageal junction (GOJ) carcinoma frequently present with dysphagia and de novo metastatic disease. There is scope to improve treatment paradigms to both address symptoms and improve survival. One method is integrating immune checkpoint inhibition with novel treatment combinations. METHODS: PALEO is a single arm, phase II clinical trial in patients with previously untreated, oligometastatic or locoregionally advanced oesophageal or GOJ carcinoma and dysphagia. PALEO is sponsored by the Australasian Gastro-Intestinal Trials Group (AGITG). Participants receive 2 weeks of therapy with concurrent hypofractionated radiotherapy of 30Gy in 10 fractions to the primary tumour, weekly carboplatin AUC2, weekly paclitaxel 50 mg/m2 and durvalumab 1500 mg q4 weekly, followed by durvalumab monotherapy continuing at 1500 mg q4weekly until disease progression, unacceptable toxicity or 24 months of therapy. A single metastasis is treated with stereotactic radiotherapy of 24Gy in 3 fractions in week 7. The trial primary endpoint is the progression free survival rate at 6 months. Secondary endpoints include duration of dysphagia relief, nutritional status change, quality of life, response rate, toxicity, progression free survival and overall survival. The tertiary endpoint is prediction of outcome based on biomarkers identified from patient serial blood samples collected pre- and post-radiotherapy. DISCUSSION: This unique investigator-initiated clinical trial is designed to simultaneously address the clinically relevant problems of dysphagia and distant disease control. The overarching aims are to improve patient nutrition, quality of life and survival with low toxicity therapy. AGITG PALEO is a multidisciplinary collaboration and will add to the understanding of the relationship between radiotherapy and the anti-tumour immune response. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry: ACTRN12619001371189 , registered 8 October 2019.


Asunto(s)
Carcinoma , Trastornos de Deglución , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Cuidados Paliativos , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Calidad de Vida , Australia , Quimioradioterapia/efectos adversos , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Gástricas/terapia , Neoplasias Gástricas/tratamiento farmacológico , Carcinoma/tratamiento farmacológico , Pueblos de Australasia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
4.
Front Oncol ; 12: 917961, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35912196

RESUMEN

Background: The globally dominant treatment with curative intent for locally advanced esophageal squamous cell carcinoma (ESCC) is neoadjuvant chemoradiotherapy (nCRT) with subsequent esophagectomy. This multimodal treatment leads to around 60% overall 5-year survival, yet with impaired post-surgical quality of life. Observational studies indicate that curatively intended chemoradiotherapy, so-called definitive chemoradiotherapy (dCRT) followed by surveillance of the primary tumor site and regional lymph node stations and surgery only when needed to ensure local tumor control, may lead to similar survival as nCRT with surgery, but with considerably less impairment of quality of life. This trial aims to demonstrate that dCRT, with selectively performed salvage esophagectomy only when needed to achieve locoregional tumor control, is non-inferior regarding overall survival, and superior regarding health-related quality of life (HRQOL), compared to nCRT followed by mandatory surgery, in patients with operable, locally advanced ESCC. Methods: This is a pragmatic open-label, randomized controlled phase III, multicenter trial with non-inferiority design with regard to the primary endpoint overall survival and a superiority hypothesis for the experimental intervention dCRT with regard to the main secondary endpoint global HRQOL one year after randomization. The control intervention is nCRT followed by preplanned surgery and the experimental intervention is dCRT followed by surveillance and salvage esophagectomy only when needed to secure local tumor control. A target sample size of 1200 randomized patients is planned in order to reach 462 events (deaths) during follow-up. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04460352.

6.
HPB (Oxford) ; 24(6): 950-962, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34852933

RESUMEN

BACKGROUND: This study: (i) assessed compliance with a consensus set of quality indicators (QIs) in pancreatic cancer (PC); and (ii) evaluated the association between compliance with these QIs and survival. METHODS: Four years of data were collected for patients diagnosed with PC. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). A multivariable analysis tested the relationship between significant patient and hospital characteristics, patient cluster effects within hospitals and survival. RESULTS: 1061 patients were eligible for this study. Significant association with improved survival were: (i) in the potentially resectable group having adjuvant chemotherapy administered following surgery or a reason documented (HR, 0.29; 95 CI, 0.19-0.46); (ii) in the locally advanced group included having chemotherapy ± chemoradiation, or a reason documented for not undergoing treatment (HR, 0.38; 95 CI, 0.25-0.58); and (iii) in the metastatic disease group included having documented performance status at presentation (HR, 0.65; 95 CI, 0.47-0.89), being seen by an oncologist in the absence of treatment (HR, 0.48; 95 CI, 0.31-0.77), and disease management discussed at a multidisciplinary team meeting (HR, 0.79; 95 CI, 0.64-0.96). CONCLUSION: Capture of a concise data set has enabled quality of care to be assessed.


Asunto(s)
Neoplasias Pancreáticas , Australia/epidemiología , Quimioterapia Adyuvante , Humanos , Modelos de Riesgos Proporcionales , Neoplasias Pancreáticas
7.
Clin Colorectal Cancer ; 21(1): 63-70, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34852972

RESUMEN

Colorectal cancer is the third most commonly diagnosed cancer, with rectal cancer accounting for 30% of cases. The current standard of care curative treatment for locally advanced rectal cancer is (chemo)radiotherapy followed by surgery and adjuvant chemotherapy. Although neoadjuvant radiotherapy has reduced the risk of local recurrence to less than 10%, the risk of distant metastasis remained high at 30% affecting patient survival. In addition, there is a recognition that there is heterogeneity in tumor biology and treatment response with good responders potentially suitable for treatment de-escalation. Therefore, new treatment sequencing and regimens were investigated. Here, we reviewed the evidence for current neoadjuvant treatment options in patients with locally advanced rectal adenocarcinoma, and highlight the new challenges in this new treatment landscape.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Quimioradioterapia , Quimioterapia Adyuvante , Humanos , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Neoplasias del Recto/radioterapia
8.
Expert Rev Anticancer Ther ; 22(1): 39-51, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34739362

RESUMEN

INTRODUCTION: Pancreatic cancer remains a challenging malignancy due to the high proportion of patients diagnosed at advanced stages and the limited treatment options. This article discusses recent evidence in the management of both localized and advanced pancreatic cancer and offers an expert opinion on current best practice. AREAS COVERED: For patients with localized disease, the evidence for adjuvant chemotherapy is discussed as well as emerging neoadjuvant approaches for resectable, borderline resectable, and locally advanced disease. Advances in metastatic disease are discussed including cytotoxic chemotherapy, targeted therapies, and the role of genomic testing to identify patients with molecular alterations. Reviewed literature included journal publications, abstracts presented at major international oncology meetings, and ongoing clinical trials databases. EXPERT OPINION: Pancreatic cancer is a devastating diagnosis and despite recent advances has a very poor prognosis. Only a minority of patients, 20%, are diagnosed with potentially curable disease. The shifting paradigm toward neoadjuvant therapy may improve resectability and survival rates; however, robust evidence is required. Thus far, there has only been limited progress in advanced stage disease. Genomic testing may potentially identify more treatment targets although limited to small subgroups.


Asunto(s)
Neoplasias Pancreáticas , Quimioterapia Adyuvante , Docentes , Humanos , Terapia Neoadyuvante , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas
9.
Clin Colorectal Cancer ; 21(2): e102-e112, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34799240

RESUMEN

BACKGROUND: To analyze the long-term outcomes and prognostic value of hematological parameters in anal cancer patients receiving intensity-modulated radiation therapy (IMRT). MATERIALS: Hospital records of consecutive patients with anal squamous cell carcinoma who received curative-intent IMRT according to a standardized contouring protocol between 2010 and 2020 were reviewed. Locoregional failure-free survival (LRFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) were estimated using the Kaplan-Meier method. Coverage of locoregional recurrences by the initial IMRT volumes were assessed. The prognostic value of pretreatment blood counts for PFS and OS were determined using Cox regression analysis. RESULTS: A total of 166 patients were analyzed with a median follow-up of 3.3 years. Forty-six percent and 54% of patients had Stage I-II and IIIA-B cancers, respectively. The 5-year LRFS, DMFS, PFS and OS were 81%, 89%, 65% and 76% respectively. Grade ≥ 3 toxicity occurred in 5% of patients. Of all patients who relapsed, 70% had only locoregional recurrence as first site of failure. Ninety percent of locoregional recurrences were in-field. Hemoglobin, neutrophil and platelet counts were associated with PFS on univariable analysis, but only cancer stage and p16 status remained prognostic on multivariable analysis. Patients with more advanced cancer stages also had higher baseline neutrophil counts. Performance status and neutrophil counts were prognostic for OS on multivariable analysis. CONCLUSION: This study affirms the long-term efficacy and safety of IMRT. Treatment resistance, rather than radiation geographic miss, is a major issue underpinning locoregional recurrences. Pretreatment blood counts were not validated to be independently prognostic for disease recurrence.


Asunto(s)
Neoplasias del Ano , Radioterapia de Intensidad Modulada , Neoplasias del Ano/radioterapia , Supervivencia sin Enfermedad , Humanos , Recurrencia Local de Neoplasia , Pronóstico , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos
10.
Int J Radiat Oncol Biol Phys ; 111(2): 502-514, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34023423

RESUMEN

PURPOSE: We examined how radiation dose per fraction (DPF) and total dose, as represented by biological effective dose (BED), can independently and differentially affect the immunomodulatory capacity of radiation therapy (RT). METHODS AND MATERIALS: AT3-OVA mammary and MC38 colorectal tumors in C57BL/6 mice were irradiated with rationally selected dose-fractionation schedules, alone or with immune-modulating or -depleting agents. Tumor growth was monitored as a readout of therapeutic response. Flow cytometry and RNA sequencing of mouse tumors and analysis of transcriptomic data sets from irradiated human cancers were used to examine the immunomodulatory effects of the different radiation schedules. RESULTS: In AT3-OVA tumors, radiation DPF rather than BED determined the ability of RT to evoke local antitumor CD8+ T cell responses and synergize with anti-PD-1 therapy. Natural killer cell-mediated control of irradiated tumors was more sensitive to radiation BED. Radiation-induced regulatory T cell (Treg) responses, which were detected in both mouse and human tumors, were a major factor underlying the differential activation of adaptive immunity by radiation DPF and the activity of natural killer cells during the early phase of response to RT. Targeted inhibition of Treg responses within irradiated tumors rescued and enhanced local tumor control by RT and permitted the generation of abscopal and immunologic memory responses, irrespective of radiation schedule. MC38 tumors did not support the induction of an amplified Treg response to RT and were highly vulnerable to its immunoadjuvant effects. CONCLUSIONS: Local radiation-induced Treg responses are influenced by radiation schedule and tumor type and are a critical determinant of the immunoadjuvant potential of RT and its ability to synergize with T cell-targeted immunotherapy.


Asunto(s)
Fraccionamiento de la Dosis de Radiación , Neoplasias Experimentales/radioterapia , Linfocitos T Reguladores/inmunología , Inmunidad Adaptativa/efectos de la radiación , Animales , Linfocitos T CD8-positivos/inmunología , Femenino , Inmunidad Innata/efectos de la radiación , Inmunomodulación , Células Asesinas Naturales/inmunología , Ratones , Ratones Endogámicos C57BL , Neoplasias Experimentales/inmunología
11.
Ann Surg Oncol ; 28(12): 7476-7486, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33891203

RESUMEN

BACKGROUND: Total neoadjuvant therapy in rectal cancer refers to the administration of chemoradiotherapy plus chemotherapy before surgery. Recent studies have shown improved pathological complete response and disease-free survival with this approach. However, survival benefits remain unproven. Our objective is to present a metaanalysis of oncological outcomes of total neoadjuvant therapy in locally advanced rectal cancer. PATIENTS AND METHODS: A comprehensive search was performed on PubMed, Medline, and Google Scholars. Studies comparing total neoadjuvant therapy with standard neoadjuvant chemoradiotherapy were included. Data extracted from the individual studies were pooled and a metaanalysis performed. The outcomes of interest are the rate of complete pathological response, nodal response, resection margin, anal preservation, anastomotic leak, local recurrence, distant recurrence, disease-free survival, and overall survival. RESULTS: There were 15 comparative studies with 2437 patients in the neoadjuvant chemoradiotherapy group and 2284 in the total neoadjuvant therapy group. The pooled complete pathological response was 22.3% in the total neoadjuvant therapy group, compared with 14.2% in the standard neoadjuvant chemoradiotherapy group (p < 0.001). Even though there was no difference in local recurrence rate, there was a significantly lower rate of distant recurrence (OR 0.81, p = 0.02), and better 3-year disease-free survival (70.6% vs. 65.3%, respectively, p < 0.001) and overall survival (84.9% vs. 82.3%, respectively, p = 0.006), favoring the total neoadjuvant therapy group. Due to significant heterogeneity in the study protocols, there remains uncertainty on the ideal chemotherapy/radiotherapy sequence. CONCLUSIONS: This study provides supporting evidence on the favorable immediate and intermediate oncological outcomes with the use of total neoadjuvant therapy for locally advanced rectal cancer.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Quimioradioterapia , Humanos , Recurrencia Local de Neoplasia/terapia , Estadificación de Neoplasias , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Recto/patología , Resultado del Tratamiento
12.
Ann Surg Oncol ; 28(8): 4151-4157, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33689079

RESUMEN

The only curative treatment for localised gastric cancer is surgical resection. However, survival outcomes post-surgery alone remain poor, particularly in those with node-positive disease with 5-year survival of approximately 30%. Therefore, additional perioperative treatment strategies such as radiotherapy and/or chemotherapy have been explored to improve survival outcomes. Early studies established the role of postoperative radiotherapy in improving locoregional control. However, there are now several adjuvant treatment options available, with many centres favouring perioperative chemotherapy. The delivery of radiotherapy in the postoperative setting can be challenging, thereby resulting in suboptimal patient compliance. Hence, the role of preoperative radiotherapy is currently being evaluated. This review focuses on and summarises the landmark clinical trials that have established the current role of radiation therapy in patients with resectable gastric and gastroesophageal adenocarcinoma, and highlights the potential for preoperative radiotherapy.


Asunto(s)
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/radioterapia , Quimioterapia Adyuvante , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/radioterapia
13.
BMJ Qual Saf ; 30(10): 792-803, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33247002

RESUMEN

BACKGROUND: Evidence-based clinical practice guidelines recommend discussion by a multidisciplinary team (MDT) to review and plan the management of patients for a variety of cancers. However, not all patients diagnosed with cancer are presented at an MDT. OBJECTIVES: (1) To identify the factors (barriers and enablers) influencing presentation of all patients to, and the perceived value of, MDT meetings in the management of patients with pancreatic cancer and; (2) to identify potential interventions that could overcome modifiable barriers and enhance enablers using the theoretical domains framework (TDF). METHODS: Semistructured interviews were conducted with radiologists, surgeons, medical and radiation oncologists, gastroenterologists, palliative care specialists and nurse specialists based in New South Wales and Victoria, Australia. Interviews were conducted either in person or via videoconferencing. All interviews were recorded, transcribed verbatim, deidentified and data were thematically coded according to the 12 domains explored within the TDF. Common belief statements were generated to compare the variation between participant responses. RESULTS: In total, 29 specialists were interviewed over a 4-month period. Twenty-two themes and 40 belief statements relevant to all the TDF domains were generated. Key enablers influencing MDT practices included a strong organisational focus (social/professional role and identity), beliefs about the benefits of an MDT discussion (beliefs about consequences), the use of technology, for example, videoconferencing (environmental context and resources), the motivation to provide good quality care (motivation and goals) and collegiality (social influences). Barriers included: absence of palliative care representation (skills), the number of MDT meetings (environmental context and resources), the cumulative cost of staff time (beliefs about consequences), the lack of capacity to discuss all patients within the allotted time (beliefs about capabilities) and reduced confidence to participate in discussions (social influences). CONCLUSIONS: The internal and external organisational structures surrounding MDT meetings ideally need to be strengthened with the development of agreed evidence-based protocols and referral pathways, a focus on resource allocation and capabilities, and a culture that fosters widespread collaboration for all stages of pancreatic cancer.


Asunto(s)
Motivación , Rol Profesional , Humanos , Grupo de Atención al Paciente , Investigación Cualitativa , Victoria
14.
Radiother Oncol ; 155: 27-32, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33065186

RESUMEN

BACKGROUND AND PURPOSE: The chemotherapy exposure during chemoradiotherapy for rectal cancer is adequate for radiosensitization but suboptimal for treatment of distant micrometastasis. This study aimed to determine tolerability, dose intensity, response, and toxicity of a novel intensified neoadjuvant treatment approach. MATERIALS AND METHODS: Eligible patients were MRI-staged T3-4NxM0 rectal adenocarcinoma. Treatment consisted of FOLFOX chemotherapy given in weeks 1, 6, and 11 with pelvic radiotherapy (25.2 Gy in 3 weeks in 1.8 Gy/fraction with oxaliplatin and 5-FU continuous infusion) given in weeks 3-5, and weeks 8-10. Surgery was performed 4-6 weeks later. The primary endpoint was tolerability defined as the percentage of patients who were able to complete the planned treatment course. Survival rates were estimated using the Kaplan-Meier method. RESULTS: Median age of the 40 patients was 61.5 years. Rectal MRI-stage was T3 in 88%. Overall, 95% completed the regimen. All patients received 50.4 Gy. Relative dose intensity (≥75%) was 92% and 98% for oxaliplatin and 5-FU, respectively. High grade toxicities included neutropenia (25% grade 3; 7.5% grade 4) and diarrhoea (10%). Pathologic CR rate was 20%. Median follow-up was 54 months. The 5-year overall survival, freedom from relapse, locoregional control, and freedom from distant metastasis of the cohort was 82%, 72%, 97% and 72%. CONCLUSIONS: Delivery of intensified neoadjuvant treatment with interdigitating chemotherapy and radiotherapy is feasible with no increase in acute perioperative complications. A larger prospective study is required to further evaluate the potential survival benefit of this design.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Fluorouracilo/uso terapéutico , Humanos , Leucovorina/efectos adversos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Oxaliplatino , Estudios Prospectivos , Neoplasias del Recto/patología , Resultado del Tratamiento
15.
PLoS One ; 15(12): e0243312, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33332372

RESUMEN

BACKGROUND: Accurate pre-operative imaging plays a vital role in patient selection for surgery and in allocating stage-appropriate therapies to patients diagnosed with pancreatic cancer (PC). This study aims to: (1) understand the current diagnosis and staging practices for PC; and (2) explore the factors (barriers and enablers) that influence the use of a pancreatic protocol computed tomography (PPCT) or magnetic resonance imaging (MRI) to confirm diagnosis and/or accurately stage PC. METHODS: Semi-structured interviews were conducted with radiologists, surgeons, gastroenterologists, medical and radiation oncologists from the states of New South Wales (NSW) and Victoria, Australia. Interviews were conducted either in person or via video conferencing. All interviews were recorded, transcribed verbatim, de-identified and data were thematically coded according to the 12 domains explored within the Theoretical Domains Framework (TDF). Common belief statements were generated to compare the variation between participant responses. FINDINGS: In total, 21 clinicians (5 radiologists, 10 surgeons, 2 gastroenterologists, 4 medical and radiation oncologists) were interviewed over a four-month-period. Belief statements relevant to the TDF domains were generated. Across the 11 relevant domains, 20 themes and 30 specific beliefs were identified. All TDF domains, with the exception of social influences were identified by participants as relevant to protocol-based imaging using either a PPCT or MRI, with the domains of knowledge, skills and environmental context and resources being offered by most participants as being relevant in influencing their decisions. CONCLUSIONS: To maximise outcomes and personalise therapy it is imperative that diagnosis and staging investigations using the most appropriate imaging modalities are conducted in a timely, efficient and effective manner. The results provide an understanding of specialists' opinion and behaviour in relation to a PPCT or MRI and should be used to inform the design of future interventions to improve compliance with this practice.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias Pancreáticas/diagnóstico por imagen , Medicina de Precisión , Tomografía Computarizada por Rayos X , Femenino , Humanos , Masculino , Estadificación de Neoplasias , Investigación Cualitativa
16.
HPB (Oxford) ; 22(2): 187-203, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31635959

RESUMEN

BACKGROUND: The aim of this systematic review is to examine patient-reported outcome measures (PROMs), their attributes and application in patients with pancreatic cancer (PC). METHOD: A systematic literature search was undertaken of articles published to June 2018 to identify PROMs applied in primary studies in PC. Characteristics of the included studies and PROMs were described with identified scales grouped into five domains. The psychometric properties of the identified PROMs were further assessed for reliability and validity among patients with PC. RESULTS: From 1688 studies screened, 170 were included. Almost half (48%) were conducted in patients with unresectable PC; the majority of these (68%) were evaluated in randomized controlled trials. Median questionnaire completion rates fell below 10% of the original cohort within 12 months in patients with unresectable PC compared to 75% in patients with resectable PC. Seventy PROMs were identified, 32 measuring unidimensional parameters (e.g. pain) and 35 measuring multidimensional (e.g. quality of life) constructs. Only five (7%) PROMs were disease-specific and 13 (19%) were validated in patients with PC. Fifty scales were grouped into 19 physical, 9 psychological, 6 psychiatric, 9 social and 7 other domains. CONCLUSION: Three multidimensional PROMs, the: (i) FACT-HEP in unresectable PC; (ii) QLQ-PAN26 (in conjunction with its core QLQ-C30 PROM) in resectable PC; and (iii) MDASI-GI are recommended as instruments to capture quality of life in patients with PC. Summarised scales and psychometric evaluation provide a framework to choose PROMs for scales not captured by the recommended PROMs.


Asunto(s)
Neoplasias Pancreáticas/terapia , Medición de Resultados Informados por el Paciente , Humanos , Neoplasias Pancreáticas/psicología , Valor Predictivo de las Pruebas , Psicometría , Reproducibilidad de los Resultados
17.
BMJ Open ; 9(9): e031434, 2019 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-31575580

RESUMEN

PURPOSE: The Upper Gastrointestinal Cancer Registry (UGICR) was developed to monitor and improve the quality of care provided to patients with upper gastrointestinal cancers in Australia. PARTICIPANTS: It supports four cancer modules: pancreatic, oesophagogastric, biliary and primary liver cancer. The pancreatic cancer (PC) module was the first module to be implemented, with others being established in a staged approach. Individuals are recruited to the registry if they are aged 18 years or older, have received care for their cancer at a participating public/private hospital or private clinic in Australia and do not opt out of participation. FINDINGS TO DATE: The UGICR is governed by a multidisciplinary steering committee that provides clinical governance and oversees clinical working parties. The role of the working parties is to develop quality indicators based on best practice for each registry module, develop the minimum datasets and provide guidance in analysing and reporting of results. Data are captured from existing data sources (population-based cancer incidence registries, pathology databases and hospital-coded data) and manually from clinical records. Data collectors directly enter information into a secure web-based Research Electronic Data Capture (REDCap) data collection platform. The PC module began with a pilot phase, and subsequently, we used a formal modified Delphi consensus process to establish a core set of quality indicators for PC. The second module developed was the oesophagogastric cancer (OGC) module. Results of the 1 year pilot phases for PC and OGC modules are included in this cohort profile. FUTURE PLANS: The UGICR will provide regular reports of risk-adjusted, benchmarked performance on a range of quality indicators that will highlight variations in care and clinical outcomes at a health service level. The registry has also been developed with the view to collect patient-reported outcomes (PROs), which will further add to our understanding of the care of patients with these cancers.


Asunto(s)
Neoplasias Gastrointestinales/terapia , Sistema de Registros , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Neoplasias del Sistema Biliar/epidemiología , Neoplasias del Sistema Biliar/terapia , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/terapia , Femenino , Neoplasias Gastrointestinales/epidemiología , Humanos , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/terapia , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/terapia , Mejoramiento de la Calidad , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/terapia
18.
Int J Radiat Oncol Biol Phys ; 103(2): 521-531, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30312716

RESUMEN

PURPOSE: There is growing interest in developing individually tailored cancer radiation therapy (RT), wherein patients with high intrinsic radiosensitivity are identified before commencing treatment, to minimize severe adverse reactions. In a previous retrospective study of severely radiosensitive RT patients, we established a functional assay with a high predictive capability. The assay involves ex vivo irradiation of peripheral blood mononuclear cells and analysis of DNA repair using the γ-H2AX assay. It is unknown whether RS is a fixed phenomenon or is modulated under different conditions. We now report the impact of RT on the apparent radiosensitivity, as reflected by the assay. METHODS AND MATERIALS: Peripheral blood mononuclear cells of 11 patients with non-small cell lung cancer were collected before, during, and after RT. Quantitative parameters derived from the nonlinear regression analysis of γ-H2AX foci were applied to examine the cellular radiation response. RESULTS: Although the repair rate and foci yield remained constant during and after RT, the "unrepairable" component of γ-H2AX foci decreased over the course of treatment in 7 patients, signifying a generally enhanced DNA repair capacity. Interestingly, enhanced repair capacity tended to be associated with a poorer response to RT. CONCLUSIONS: Although generalization of these results into normal and tumor tissues warrants further investigation, the findings of this study have important implications in future strategies for identifying radiosensitive individuals before exposure to RT. We can anticipate that the threshold values that will discriminate radiosensitive patients in a future prospective trial will differ from those established in the retrospective study.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Reparación del ADN/efectos de la radiación , Leucocitos Mononucleares/citología , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/radioterapia , Anciano , Apoptosis , Daño del ADN , Femenino , Histonas/metabolismo , Humanos , Cinética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Estudios Prospectivos , Tolerancia a Radiación , Análisis de Regresión , Resultado del Tratamiento
19.
Asia Pac J Clin Oncol ; 15(1): 75-81, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30536770

RESUMEN

PURPOSE: Mitomycin C (MMC) plus standard 5-fluorouracil (FU) infusion in weeks 1 and 5 often contributes to radiotherapy interruptions and possibly less-than-ideal outcomes in anal cancer. This study was to evaluate alternative strategies for chemotherapy delivery that might be less toxic or more efficacious, and outcomes of patient-initiated treatment interruption for severe acute toxicity. MATERIALS AND METHODS: This was a prospective, nonrandomized study for patients with T1-4N0-3M0 anal squamous carcinoma. Radiotherapy of 54 Gy in 30 fractions over 6 weeks was given with infusion FU 300 mg/m2 /day for 96 hours/week for 6 weeks plus bolus MMC at 10 mg/m2 on D1. RESULTS: Fifty patients were recruited (72% female). Median age was 60.5 years (35-84). Forty-seven patients (94%) received 54 Gy. Median duration of chemoradiation was 39 days (37-105). Grade 3 and 4 acute toxicity were observed in 66%. Thirty-one percent with severe acute toxicity developed severe late toxicity. Of those who experienced severe late skin toxicity, 29% did not have severe acute toxicity. Disease-free survival at 5 years was 74% (95% confidence interval [CI], 60-84), and at 9 years 61% (95% CI, 46-74). Overall survival at 5 years was 84% (95% CI, 71-92), and at 9 years 67% (95% CI, 50-81). Colostomy-free survival at 5 years was 70% (95% CI, 56-81), and at 9 years 57% (95% CI, 40-72). CONCLUSION: It is feasible to deliver chemoradiation with bolus MMC and protracted infusion FU for anal cancer. Efficacy and toxicity of this regimen seem similar to conventional chemoradiation with FU/MMC. Acute skin toxicity is not a reliable predictor of severe late skin toxicity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Ano/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Canal Anal , Neoplasias del Ano/patología , Carcinoma de Células Escamosas/patología , Femenino , Fluorouracilo/administración & dosificación , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Mitomicina/administración & dosificación , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia
20.
PLoS Genet ; 14(11): e1007832, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30496175

RESUMEN

Meiotic recombination plays a critical role in sexual reproduction by creating crossovers between homologous chromosomes. These crossovers, along with sister chromatid cohesion, connect homologs to enable proper segregation at Meiosis I. Recombination is initiated by programmed double strand breaks (DSBs) at particular regions of the genome. The meiotic recombination checkpoint uses meiosis-specific modifications to the DSB-induced DNA damage response to provide time to convert these breaks into interhomolog crossovers by delaying entry into Meiosis I until the DSBs have been repaired. The meiosis-specific kinase, Mek1, is a key regulator of meiotic recombination pathway choice, as well as being required for the meiotic recombination checkpoint. The major target of this checkpoint is the meiosis-specific transcription factor, Ndt80, which is essential to express genes necessary for completion of recombination and meiotic progression. The molecular mechanism by which cells monitor meiotic DSB repair to allow entry into Meiosis I with unbroken chromosomes was unknown. Using genetic and biochemical approaches, this work demonstrates that in the presence of DSBs, activated Mek1 binds to Ndt80 and phosphorylates the transcription factor, thus inhibiting DNA binding and preventing Ndt80's function as a transcriptional activator. Repair of DSBs by recombination reduces Mek1 activity, resulting in removal of the inhibitory Mek1 phosphates. Phosphorylation of Ndt80 by the meiosis-specific kinase, Ime2, then results in fully activated Ndt80. Ndt80 upregulates transcription of its own gene, as well as target genes, resulting in prophase exit and progression through meiosis.


Asunto(s)
Reparación del ADN , Proteínas de Unión al ADN/metabolismo , MAP Quinasa Quinasa 1/metabolismo , Meiosis/fisiología , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Puntos de Control del Ciclo Celular , Secuencia Conservada , Roturas del ADN de Doble Cadena , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Genes Fúngicos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , MAP Quinasa Quinasa 1/genética , Meiosis/genética , Modelos Biológicos , Modelos Moleculares , Mutación , Fase Paquiteno/genética , Fase Paquiteno/fisiología , Fosforilación , Dominios y Motivos de Interacción de Proteínas , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteolisis , Reparación del ADN por Recombinación , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Homología de Secuencia de Aminoácido , Factores de Transcripción/química , Factores de Transcripción/genética
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