173 research outputs found
Rectal cancer: steps towards tailored treatment
Treatment options for rectal cancer include surgery, radiation therapy and chemotherapy. In recent years, there has been an increased interest in organ-saving treatment of rectal cancer. This dissertation is aimed at tailoring the treatment of patients with rectal cancer. Three aspects were studied, namely the use of PET scans to make radiation therapy more accurate, the development of models to predict reactions to radiation therapy and the intensifying of radiation therapy to increase the chances of the tumour reacting to treatment. PET imaging proved to be useful in making radiation therapy more accurate. Furthermore, it was found that reactions to radiation therapy can be predicted by using PET scans and blood samples, among other things
Modulation of cell death in the tumor micro environment
The microenvironment of solid human tumors is characterized by heterogeneity in oxygenation. Hypoxia arises early in the process of tumor development because rapidly proliferating tumor cells outgrow the capacity of the host vasculature. Formation of solid tumors thus requires coordination of angiogenesis with continued tumor cell proliferation. However, despite such neovascularization, hypoxia is persistent and frequently found in tumors at the time of diagnosis. Tumors with low oxygenation have a poor prognosis, and strong evidence suggests this is because of the effects of hypoxia on malignant progression, angiogenesis, metastasis, and therapy resistance. The presence of viable hypoxic cells is likely a reflection of the development of hypoxia tolerance resulting from modulation of cell death in the microenvironment. This acquired feature has been explained on the basis of clonal selection-the hypoxic microenvironment selects cells capable of surviving in the absence of normal oxygen availability. However, the persistence and frequency of hypoxia in solid tumors raises a second potential explanation. We suggest that stable microregions of hypoxia may play a positive role in tumor growth. Although hypoxia inhibits cell proliferation and in tumor cells will eventually induce cell death, hypoxia also provides angiogenic and metastatic signals. The development of hypoxia tolerance will thus allow prolonged survival in the absence of oxygen and generation of a persistent angiogenic signal. We will discuss the concept of hypoxia tolerance and review mechanisms used by cancer cells to acquire this phenotype. The concept of hypoxia tolerance has important implications for current and future therapeutic approaches. Most therapeutic efforts to combat hypoxia have focused on targeting the presence of hypoxia itself. Our hypothesis predicts that targeting the biological responses to hypoxia and the pathways leading to hypoxia tolerance may also be attractive therapeutic strategies.Copyright 2003, Elsevier Science (USA). All rights reserved
Phase I trial of the combination of the Akt inhibitor nelfinavir and chemoradiation for locally advanced rectal cancer
PURPOSE: To investigate the toxicity of nelfinavir, administered during preoperative chemoradiotherapy (CRT) in patients with locally advanced cancer. MATERIAL AND METHODS: Twelve patients were treated with to 50.4Gy combined with capecitabine 825mg/m2 BID. Three dose levels nelfinavir were tested: 750mg BID (DL1), 1250mg BID (DL2) and an level of 1000mg BID (DL3). Surgery was performed between 8 and 10weeks completion of CRT. Primary endpoint was dose-limiting toxicity (DLT), any grade 3 or higher non-hematological or grade 4 or higher toxicity. RESULTS: Eleven patients could be analyzed: 5 were treated in DL2 and 3 in DL3. The first 3 patients in DL1 did not develop a DLT. In patient developed gr 3 diarrhea, 1 patient had gr 3 transaminase patient had a gr 3 cholangitis with unknown cause. An intermediate dose tested in DL3. In this group 2 patients developed gr 3 diarrhea and 1 3 transaminase elevation and gr 4 post-operative wound complication. patients achieved a pathological complete response (pCR). CONCLUSIONS: 750mg BID was defined as the recommended phase II dose in combination capecitabine and 50.4Gy pre-operative radiotherapy in rectal cancer. response evaluations are promising, but a further phase II study is more information about efficacy of this treatment regimen
REPEATED POSITRON EMISSION TOMOGRAPHY-COMPUTED TOMOGRAPHY AND PERFUSION-COMPUTED TOMOGRAPHY IMAGING IN RECTAL CANCER: FLUORODEOXYGLUCOSE UPTAKE CORRESPONDS WITH TUMOR PERFUSION
Lymph node response to chemoradiotherapy in oesophageal cancer patients: relationship with radiotherapy fields
Background
The presence of lymph node metastasis (LNmets) is a poor prognostic factor in oesophageal cancer (OeC) patients treated with neoadjuvant chemoradiotherapy (nCRT) followed by surgery. Tumour regression grade (TRG) in LNmets has been suggested as a predictor for survival. The aim of this study was to investigate whether TRG in LNmets is related to their location within the radiotherapy (RT) field.
Methods
Histopathological TRG was retrospectively classified in 2565 lymph nodes (LNs) from 117 OeC patients treated with nCRT and surgery as: (A) no tumour, no signs of regression; (B) tumour without regression; (C) viable tumour and regression; and (D) complete response. Multivariate survival analysis was used to investigate the relationship between LN location within the RT field, pathological TRG of the LN and TRG of the primary tumour.
Results
In 63 (54%) patients, viable tumour cells or signs of regression were seen in 264 (10.2%) LNs which were classified as TRG-B (n = 56), C (n = 104) or D (n = 104) LNs. 73% of B, C and D LNs were located within the RT field. There was a trend towards a relationship between LN response and anatomical LN location with respect to the RT field (p = 0.052). Multivariate analysis showed that only the presence of LNmets within the RT field with TRG-B is related to poor overall survival.
Conclusion
Patients have the best survival if all LNmets show tumour regression, even if LNmets are located outside the RT field. Response in LNmets to nCRT is heterogeneous which warrants further studies to better understand underlying mechanisms
Combined use of hyperthermia and radiation therapy for treating locally advanced cervical carcinoma (Withdrawn Paper, art. no. CD006377, 2010)
Hyperthermia is a type of cancer treatment in which body tissue is exposed to high temperatures to damage and kill cancer cells. It was introduced into clinical oncology practice several decades ago. Positive clinical results, mostly obtained in single institutions, resulted in clinical implementation albeit in a limited number of cancer centres worldwide. Because large scale randomised clinical trials (RCTs) are lacking, firm conclusions cannot be drawn regarding its definitive role as an adjunct to radiotherapy in the treatment of locally advanced cervical carcinoma (LACC).To assess whether adding hyperthermia to standard radiotherapy for LACC has an impact on (1) local tumour control, (2) survival and (3) treatment related morbidity.The electronic databases of the Cochrane Central Register of Controlled Trials (CENTRAL), (Issue 1, 2009) and Cochrane Gynaecological Cancer Groups Specialised Register, MEDLINE, EMBASE, online databases for trial registration, handsearching of journals and conference abstracts, reviews, reference lists, and contacts with experts were used to identify potentially eligible trials, published and unpublished until January 2009.RCTs comparing radiotherapy alone (RT) versus combined hyperthermia and radiotherapy (RHT) in patients with LACC.Between 1987 and 2009 the results of six RCTs were published, these were used for the current analysis.74% of patients had FIGO stage IIIB LACC. Treatment outcome was significantly better for patients receiving the combined treatment (Figures 1 to 3). The pooled data analysis yielded a significantly higher complete response rate (relative risk (RR) 0.56; 95% confidence interval (CI) 0.39 to 0.79; p <0.001), a significantly reduced local recurrence rate at 3 years (hazard ratio (HR) 0.48; 95% CI 0.37 to 0.63; p <0.001) and a significanly better overall survival (OS) at three years following the combined treatment with RHT(HR 0.67; 95% CI 0.45 to 0.99; p = 0.05). No significant difference was observed in treatment related acute (RR 0.99; 95% CI 0.30 to 3.31; p = 0.99) or late grade 3 to 4 toxicity (RR 1.01; CI 95% 0.44 to 2.30; p = 0.96) between both treatments.The limited number of patients available for analysis, methodological flaws and a significant over-representation of patients with FIGO stage IIIB prohibit drawing definite conclusions regarding the impact of adding hyperthermia to standard radiotherapy. However, available data do suggest that the addition of hyperthermia improves local tumour control and overall survival in patients with locally advanced cervical carcinoma without affecting treatment related grade 3 to 4 acute or late toxicity
Whole breast and regional nodal irradiation in prone versus supine position in left sided breast cancer
Background: Prone whole breast irradiation (WBI) leads to reduced heart and lung doses in breast cancer patients receiving adjuvant radiotherapy. In this feasibility trial, we investigated the prone position for whole breast + lymph node irradiation (WB + LNI).
Methods: A new support device was developed for optimal target coverage, on which patients are positioned in a position resembling a phase from the crawl swimming technique (prone crawl position). Five left sided breast cancer patients were included and simulated in supine and prone position. For each patient, a treatment plan was made in prone and supine position for WB + LNI to the whole axilla and the unoperated part of the axilla. Patients served as their own controls for comparing dosimetry of target volumes and organs at risk (OAR) in prone versus in supine position.
Results: Target volume coverage differed only slightly between prone and supine position. Doses were significantly reduced (P < 0.05) in prone position for ipsilateral lung (Dmean, D2, V5, V10, V20, V30), contralateral lung (Dmean, D2), contralateral breast (Dmean, D2 and for total axillary WB + LNI also V5), thyroid (Dmean, D2, V5, V10, V20, V30), oesophagus (Dmean and for partial axillary WB + LNI also D2 and V5), skin (D2 and for partial axillary WB + LNI V105 and V107). There were no significant differences for heart and humeral head doses.
Conclusions: Prone crawl position in WB + LNI allows for good breast and nodal target coverage with better sparing of ipsilateral lung, thyroid, contralateral breast, contralateral lung and oesophagus when compared to supine position. There is no difference in heart and humeral head doses
Generation of 3 spinocerebellar ataxia type 1 (SCA1) patient-derived induced pluripotent stem cell lines LUMCi002-A, B, and C and 2 unaffected sibling control induced pluripotent stem cell lines LUMCi003-A and B
Spinocerebellar ataxia type 1 (SCA1) is a hereditary neurodegenerative disease caused by a CAG repeat expansion in exon 8 of the ATXN1 gene. We generated induced pluripotent stem cells (hiPSCs) from a SCA1 patient and his non-affected sister by using non-integrating Sendai Viruses (SeV). The resulting hiPSCs are SeVfree, express pluripotency markers, display a normal karyotype, retain the mutation (length of the CAG repeat expansion in the ATXN1 gene) and are able to differentiate into the three germ layers in vitro
The predictive and prognostic potential of plasma telomerase reverse transcriptase (TERT) RNA in rectal cancer patients
Background: Preoperative chemoradiotherapy (CRT) followed by surgery is the standard care for locally advanced rectal cancer,
but tumour response to CRT and disease outcome are variable. The current study aimed to investigate the effectiveness of plasma
telomerase reverse transcriptase (TERT) levels in predicting tumour response and clinical outcome.
Methods: 176 rectal cancer patients were included. Plasma samples were collected at baseline (before CRT\ubcT0), 2 weeks after
CRT was initiated (T1), post-CRT and before surgery (T2), and 4\u20138 months after surgery (T3) time points. Plasma TERT mRNA levels
and total cell-free RNA were determined using real-time PCR.
Results: Plasma levels of TERT were significantly lower at T2 (Po0.0001) in responders than in non-responders. Post-CRT TERT
levels and the differences between pre- and post-CRT TERT levels independently predicted tumour response, and the prediction
model had an area under curve of 0.80 (95% confidence interval (CI) 0.73\u20130.87). Multiple analysis demonstrated that patients with
detectable TERT levels at T2 and T3 time points had a risk of disease progression 2.13 (95% CI 1.10\u20134.11)-fold and 4.55 (95% CI
1.48\u201313.95)-fold higher, respectively, than those with undetectable plasma TERT levels.
Conclusions: Plasma TERT levels are independent markers of tumour response and are prognostic of disease progression in rectal
cancer patients who undergo neoadjuvant therapy
Treatment of locally advanced rectal cancer and synchronous liver metastases:multicentre comparison of two treatment strategies
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