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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Evaluation of ultra-hypofractionated radiotherapy with focal boost for prostate cancer by histological grades / Utvärdering av ultrahypofraktionerad strålbehandling med fokal boost för prostatacancer baserat på histologiska grader

Nilsson, Anneli January 2024 (has links)
Prostate cancer (PCa) is the second most common cancer diagnosis for men and the fifth leading cause of cancer-related death worldwide. A common treatment strategy for PCa is external beam radiation therapy (EBRT), where high doses of radiation are used to kill cancer cells. Recent developments in RT include maintaining acceptable side effects during intensified treatment over fewer treatment occasions (hypofractionation) and boosting the level of radiation to the gross tumor volume (GTV) visible on multiparametric magnetic resonance imaging (mpMRI) and positron emission tomography (PET). Without a histopathological (HP) reference, the dose distribution cannot be compared to the varying grades of aggressivity within the cancer, known as ISUP grade groups (IGGs). The aim of this master thesis project was to explore the dose distribution over IGGs using a gold standard HP reference and investigate the mitigating effects of rectal spacers, following a hypofractionated RT schedule with focal boosts. The dataset consists of 15 patients, planned for radical prostatectomy. These patients harbored high-risk disease (IGG ≥ 4) in the GTV. HP evaluations following surgery resulted in physical slices of the prostate, showing the location and IGG of lesions. EBRT treatment plans that combined an ultra-hypofractionation strategy with a boost to the GTV were made. The dose distributions were evaluated by dose volume histograms (DVHs) over the target volumes, organs at risks (OARs) and the lesions. Robust evaluations of targets and OARs were performed by recalculating doses following translations of the patient by 2 mm in all directions. Similarly, lesions were shifted by 2 mm in all directions with respect to the nominal dose plan to estimate the sensitivity to motion. The effects of the translations were assessed by examining the impact on the DVHs and percentage of passed clinical goals. Two viable dose plans for each patient were produced, one for a 10 mm spacer and one for 8 mm. Both plans fulfill all rectum goals. For the 10 mm plan, the average median dose (D50) was greater than the prescribed prostate dose (42.7 Gy) for all IGGs by atleast 1.1 Gy. The D50 of the higher grades (IGG 3, 4 and 5) were 47.5, 46.4 and 48.7 Gy, meaning that they were closer to the desired GTV dose 49.0 Gy than the prescribed prostate dose. This thesis project showed that it is possible to reach high GTV doses while sparing the OARs and that the higher IGGs received a higher dose than the lower grades. Examining rectal dose depending on different spacer thicknesses allowed us to recommend a spacer thickness that is safe to use, which can provide increased patient comfort while saving time and resources.
192

Bystander Cells and Prognosis in Hodgkin Lymphoma

Molin, Daniel January 2002 (has links)
<p>Hodgkin lymphoma (HL) is characterised histologically by a minority of malignant Hodgkin and Reed-Sternberg (HRS) cells surrounded by benign cells, and clinically by a relatively good prognosis. The treatment, however, leads to a risk of serious side effects. Knowledge about the biology of the disease, particularly the interaction between the HRS cells and the surrounding cells, is essential in order to improve diagnosis and treatment. </p><p>HL patients with abundant eosinophils in the tumours have a poor prognosis, therefore the eosinophil derived protein eosinophil cationic protein (ECP) was studied. Serum-ECP (S-ECP) was elevated in most HL patients. It correlated to number of tumour eosinophils, nodular sclerosis (NS) histology, and the negative prognostic factors high erythrocyte sedimentation rate (ESR) and blood leukocyte count (WBC). A polymorphism in the ECP gene (434(G>C)) was identified and the 434GG genotype correlated to NS histology and high ESR.</p><p>The poor prognosis in patients with abundant eosinophils in the tumours has been proposed to depend on HRS cell stimulation by the eosinophils via a CD30 ligand (CD30L)-CD30 interaction. However, CD30L mRNA and protein were detected in mast cells and the predominant CD30L expressing cell in HL is the mast cell. Mast cells were shown to stimulate HRS cell lines via CD30L-CD30 interaction. The number of mast cells in HL tumours correlated to worse relapse-free survival, NS histology, high WBC, and low blood haemoglobin. </p><p>Survival in patients with early and intermediate stage HL, diagnosed between 1985 and 1992, was generally favourable and comparatively limited treatment was sufficient to produce acceptable results for most stages. The majority of relapses could be salvaged. Patients treated with a short course of chemotherapy and radiotherapy had an excellent outcome.</p><p>In conclusion prognosis is favourable in early and intermediate stages and there are possibilities for further improvements based on the fact that mast cells and eosinophils affect the biology and prognosis of HL.</p>
193

Bystander Cells and Prognosis in Hodgkin Lymphoma

Molin, Daniel January 2002 (has links)
Hodgkin lymphoma (HL) is characterised histologically by a minority of malignant Hodgkin and Reed-Sternberg (HRS) cells surrounded by benign cells, and clinically by a relatively good prognosis. The treatment, however, leads to a risk of serious side effects. Knowledge about the biology of the disease, particularly the interaction between the HRS cells and the surrounding cells, is essential in order to improve diagnosis and treatment. HL patients with abundant eosinophils in the tumours have a poor prognosis, therefore the eosinophil derived protein eosinophil cationic protein (ECP) was studied. Serum-ECP (S-ECP) was elevated in most HL patients. It correlated to number of tumour eosinophils, nodular sclerosis (NS) histology, and the negative prognostic factors high erythrocyte sedimentation rate (ESR) and blood leukocyte count (WBC). A polymorphism in the ECP gene (434(G&gt;C)) was identified and the 434GG genotype correlated to NS histology and high ESR. The poor prognosis in patients with abundant eosinophils in the tumours has been proposed to depend on HRS cell stimulation by the eosinophils via a CD30 ligand (CD30L)-CD30 interaction. However, CD30L mRNA and protein were detected in mast cells and the predominant CD30L expressing cell in HL is the mast cell. Mast cells were shown to stimulate HRS cell lines via CD30L-CD30 interaction. The number of mast cells in HL tumours correlated to worse relapse-free survival, NS histology, high WBC, and low blood haemoglobin. Survival in patients with early and intermediate stage HL, diagnosed between 1985 and 1992, was generally favourable and comparatively limited treatment was sufficient to produce acceptable results for most stages. The majority of relapses could be salvaged. Patients treated with a short course of chemotherapy and radiotherapy had an excellent outcome. In conclusion prognosis is favourable in early and intermediate stages and there are possibilities for further improvements based on the fact that mast cells and eosinophils affect the biology and prognosis of HL.
194

Betydelser av bröstcancer i ett livssammanhang / Meanings of breast cancer in a life context

Lilliehorn, Sara January 2013 (has links)
The aim of the thesis is to describe and analyse how a group of women experience that their every-day lives are affected during and after primary breast cancer treatment. The thesis is a consecutive, longitudinal study that takes an explorative qualitative approach. Seventy-one women younger than 60 years of age with primary breast cancer were consecutively included in the study. The women were interviewed four or five times over a period of 4 to 6 years from end of radiotherapy. The analyses of the interviews were inspired by grounded theory and narrative analysis.  The thesis encompasses four papers. Paper I focused on the women’s contact with health care. The results of this study indicate that it is crucial for patients in a vulnerable situation to be admitted into a supportive system – ‘admitted into a helping plan’ – that, more or less explicitly, displays a well-thought-out plan of care. This is a process built on individual relationships with members of the health-care staff, but it ends up in a relationship to health care as a helping system, a ‘safe haven’ to attach to. Study II explored the women’s ideas about what motivated and discouraged their return to work. The results illustrate that the meaning of work fluctuates over time and that the processes of returning to work are conditioned by the patients’ individual life situations. Returning to work was regarded as an important part of the healing process because of how it generated and structured the women’s everyday lives. Returning to work meant demonstrating well-being and normalcy after breast cancer. Study III examined how life was lived and valued during and after treatment for breast cancer compared to pre-cancer life. The analysis showed that being afflicted with breast cancer was evaluated from a context of the women’s former everyday lives and stressed that how the women experienced breast cancer was a matter of personal circumstances. Study IV focused on how the women experienced and dealt with their altered bodies. The results showed that the women followed three different body-mind trajectories that depended to a significant extent on the severity of side effects and bodily alterations that resulted from their treatments. Being afflicted by breast cancer implies vulnerability and losses, but it can also involve benefits and provide new perspectives on life. How the overall breast cancer experience is valued seems to be very much a matter of circumstances in everyday life. This thesis highlights circumstances that focus in particular on contacts with health care, the body, the work situation, and the family situation.
195

Interactions between Rho-ROCK signaling and the tumor microenvironment in neuroblastoma

Pepich, Adena January 2021 (has links)
Neuroblastoma is a childhood cancer of the peripheral sympathetic nervous system, emerging from cells of the neural crest. In Sweden, neuroblastoma accounts for 20 cases out of all, 300-350, pediatric cancer cases each year (Barncancerfonden 2019, Turup on behalf of Cancer Centrum 2019). This cancer often appears in the sympathetic ganglia and/or the adrenal gland and has a high rate of metastasis that often results in morbidity (Matthay et al. 2016). Recent findings implicating a mutation in the Rho/Rac signaling pathway, a pathway involved in neural crest differentiation and migration, were found in every fourth neuroblastoma patient (Dyberg et al. 2017) These mutations tend to shift Rho to a more active state which is believed to lead to more downstream Rho-associated Kinase (ROCK) activation. While inhibition of ROCK has been seen to promote MYCN protein degradation, induce neuroblastoma cell differentiation and repress neuroblastoma growth in vitro and in vivo (Dyberg et al. 2017). Rho/ROCK signaling pathway effects on cytoskeletal arrangement and cell shape have also been suggested to be involved in tumor promoted changes of the TME (Johan and Samuel, 2018). In this master’s thesis project, we explore the effects of the Rho/ROCK pathway on the tumor microenvironment (TME) and immune response (IR) in neuroblastoma. More specifically we are focusing on populations of T cells, macrophages and fibroblasts in tumors, and looking into tumor vascular structure (such as blood vessel) and extracellular matrix (ECM) formation after ROCK inhibitor treatment within neuroblastoma tumors from transgenic mice model TH-MYCN and multi-cellular tumor spheroids (MCTS), a three-dimensional (3D) in vitro model simulating TME in neuroblastoma cell lines. Through our studies we hope to find insights into the Rho/ROCK signaling pathway and involvement of the tumor microenvironment in cancer therapy, while elucidating potential new drugs and drug targets for improving outcomes in neuroblastoma treatment.
196

Aspects of Non-Neuronal Signalling Functions of Acetylcholine in Colorectal Cancer : Roles for the α7nAChR

Novotny, Ann January 2009 (has links)
No description available.
197

Staging and tumor biological mechanisms of lymph node metastasis in invasive urinary bladder cancer

Aljabery, Firas January 2017 (has links)
Aim: To study the possibility of detecting lymph node metastasis in locally advanced urinary bladder cancer (UBC) treated with radical cystectomy (RC) by using preoperative positron emission tomography/computed tomography (PET/CT) and peroperative sentinel node biopsy (SNB) technique. We also investigate the clinical significance of macrophage traits expression by cancer cells, M2-macrophage infiltration (MI) in tumor stroma and the immunohistochemical expression of biomarkers in cancer cells in relation to clinicopathologic data. Patients and Methods: We studied prospectively 122 patients with UBC, pathological stage pT1–pT4 treated with RC and pelvic lymph node dissection (PLND) during 2005–2011 at the Department of Urology, Linköping University Hospital. In the first study, we compared the results of preoperative PET/CT and conventional CT with the findings of postoperative histopathological evaluation of lymph nodes (LNs). In the second study we investigated the value of SNB technique for detecting pathological LNs during RC in patients with UBC. W also examined the significance of the primary tumor location in the bladder in predicting the site of LN metastases, and the prognostic significance of lympho-vascular invasion (LVI) and lymph node metastasis density (LNMD) on survival. In the third study, we investigate the clinical significance of macrophage infiltration (MI) in tumor stroma and macrophage-traits expression by tumor cells. In the fourth study, we investigate the cell cycle suppression proteins p53, p21, pRb, p16, p14 ARF as well as tumors proliferative protein Ki67 and DNA repair protein ERCC1 expression in cancer cells. The results were compared with clinical and pathological characteristics and outcome. Results: Prior to RC, PET/CT was used to detect LN metastasis in 54 patients. PET/CT had 41% sensitivity, 86% specificity, 58% PPV, and 76% NPV, whereas the corresponding figures for conventional CT were 41%, 89%, 64%, and 77%. SNB was performed during RC in 103 patients. A median number of 29 (range 7–68) nodes per patient were examined. SNs were detected in 83 out of 103 patients (81%). The sensitivity and specificity for detecting metastatic disease by SNB varied among LN stations, with average values of 67% -90%. LNMD or ≥8% and LVI were significantly related to shorter survival. In 103 patients, MI was high in 33% of cases, while moderate and low infiltration occurred in 42% and 25% of tumors respectively. Patients with tumors containing high and moderate compared to low MI had low rate of LN metastases (P=0.06) and improved survival (P=0.06), although not at significant level. The expression of different tumor suppression proteins was altered in 47-91% of the patients. There were no significant association between cancer specific survival (CSS) and any of the studied biomarkers. In case of altered p14ARF, ERCC1 or p21, CSS was low in case of low p53 immunostaining but increased in case of p53 accumulation, although not at a significant level, indicating a possible protective effect of p53 accumulation in these cases. Conclusion: PET/ CT provided no improvement over conventional CT in detection and localization of regional LN metastases in bladder cancer. It is possible to detect the SN but the technique is not a reliable for perioperative localization of LN metastases; however, LVI and LNMD at a cut-off level of 8% had significant prognostic values. MI in the tumor microenvironment but not CD163 expression in tumor cells seems to be synergistic with the immune response against urinary bladder cancer. Our results further indicate that altered p53 might have protective effect on survival in case of altered p14ARF, p21, or ERCC1 indicating an interaction between these biomarkers.
198

Eating difficulties and parental feeding strategies during and after childhood cancer treatment: The experiences of parents. : A systematic literature review.

Philippe, Kaat January 2017 (has links)
Childhood cancer is a life-threatening disease with a profound impact on the family. Treatment side-effects and accompanied dietary difficulties are for example severe stressors, as appropriate nutrition is important for the treatment success and quality of life. In addition, (unhealthy) dietary patterns established in childhood tend to maintain in survivors. Parents are key players in feeding and establishing these pat-terns, though, systematic research on how parents experience these dietary difficulties is limited. This study aimed at exploring parental experiences of children’s dietary changes and difficulties during cancer treatment and after completion: what feelings do parents experience regarding their child’s dietary changes and difficulties, what feeding strategies to they apply to handle these difficulties, and how did they experience professional support and what are parental support needs. A systematic literature review was conducted and resulted in 21 suitable articles. The children were 0-21 years old, had various types of cancer, and received various types of therapy. Findings showed that parents reported many dietary changes (e.g. increase or decrease in food intake) and associated symptoms (e.g. nausea, changed tastes) during and after the cancer treatment course. Parents reported mainly negative feelings towards these dietary difficulties (e.g. distress and anxiety) and applied a wide range of behavioural feeding strategies, both negative (e.g. pressure to eat) and positive (e.g. provide healthy food) strategies. Parents also used complementary and alternative medicine. A high need for informational support regarding eating and feeding was expressed by parents during treatment, a need for emotional and practical support to a lower extent. These results showed how frequent and profound eating and feeding difficulties are in the childhood cancer and survivor population, and their (negative) impact on parents. Parents consequently need more support: they need oral and written information to set realistic expectations and install appropriate feeding strategies. This is important for the child’s nutritional status and general health both during and after cancer.
199

Response to neoadjuvant treatment in rectal cancer surgery

Loftås, Per January 2016 (has links)
Rectal cancer is one of the three most common malignancies in Sweden with an annual incidence of about 2000 cases. Current treatment consists of surgical resection of the rectum including the loco-regional lymph nodes in the mesorectum. In advanced cases, neoadjuvant chemo-radiotherapy (CRT) prior to the operative treatment reduces local recurrences and enables surgery. The neoadjuvant treatment can also eradicate the tumour completely, i.e. complete response. This research project was designed to investigate the effects of preoperative radiotherapy/ CRT and analyze methods to predict response to CRT. Study I investigated the expression of the FXYD-3 protein with immunohistochemistry in rectal cancer, with or without preoperative radiotherapy. The results from the total cohort showed that, strong FXYD-3 expression was correlated to infiltrative tumour growth (p = 0.02). In the radiotherapy group, strong FXYD-3 expression was related to an unfavourable prognosis (p = 0.02). Tumours with strong FXYD-3 expression had less tumour necrosis (p = 0.02) after radiotherapy. FXYD-3 expression in the primary tumour was increased compared to normal mucosa (p=0.008). We concluded that FXYD-3 expression was a prognostic factor in patients receiving preoperative radiotherapy for rectal cancer. Study II investigated FXYD-3 expression in tumours that developed local recurrences following surgery and compared this with expression in tumours that did not develop local recurrences. There was no difference in the expression of FXYD-3 between the group that developed local recurrences and the group that did not develop local recurrences. There was no difference in survival between those with strong or weak FXYD-3 expression. We concluded that this study could not confirm the findings from study 1 i.e. that FXYD-3 expression has prognostic significance in rectal cancer. Study III was a register-based study on the incidence and effects of complete response to neoadjuvant treatment. Eight per cent of the patients with adequate CRT to achieve complete response also had a complete histological response of the luminal tumor in the resected bowel. Sixteen per cent of that group had remaining lymph node metastases in the operative specimen. Chemotherapy together with radiotherapy doubled the chance of complete response in the luminal tumour. Patients with remaining lymph node metastases had a lower survival rate compared to those without. We concluded that residual nodal involvement after neoadjuvant treatment was an important factor for reduced survival after complete response in the luminal tumour. Study IV followed up the results from the previous study by re-evaluating magnetic resonance imaging (MRI)- images in patients with complete tumour response. Two experienced MRI radiologists performed blinded re-staging of post CRT MR- images from patients with complete response in the luminal tumour. One group with lymph node metastases and another one without were studied and the results compared with the pathology reports. The sensitivity, specificity, and positive and negative predicted values for correct staging of positive lymph nodes was 37%, 84%, 70% and 57%. The size of the largest lymph node (4.5 mm, p=0.04) seemed to indicate presence of a tumour positive lymph node. We concluded that MRI couldn’t correctly stage patients for lymph node metastases in patients with complete response to CRT in the luminal tumour.
200

Recurrent Genetic Mutations in Lymphoid Malignancies

Young, Emma January 2017 (has links)
In recent years, the genetic landscape of B-cell derived lymphoid malignancies, including chronic lymphocytic leukemia (CLL), has been rapidly unraveled, identifying recurrent genetic mutations with potential clinical impact. Interestingly, ~30% of all CLL patients can be assigned to more homogeneous subsets based on the expression of a similar or “stereotyped” B-cell receptor (BcR). Considering that biased distribution of genetic mutations was recently indicated in specific stereotyped subsets, in paper I, we screened 565 subset cases, preferentially assigned to clinically aggressive subsets, and confirm the SF3B1 mutational bias in subset #2 (45%), but also report on similarly marked enrichment in subset #3 (46%). In contrast, NOTCH1 mutations were predominantly detected in subsets #1, #8, #59 and #99 (22-34%). This data further highlights a subset-biased acquisition of genetic mutations in the pathogenesis of at least certain subsets. Aberrant NF-κB signaling due to a deletion within the NFKBIE gene previously reported in CLL warranted extended investigation in other lymphoid malignancies. Therefore, in paper II, we screened 1460 patients with various lymphoid malignancies for NFKBIE deletions and reported enrichment in classical Hodgkin lymphoma (27%) and primary mediastinal B-cell lymphoma (PMBL) (23%). NFKBIE-deleted PMBL cases had higher rates of chemorefractoriness and inferior overall survival (OS). NFKBIE-deletion status remained an independent prognostic marker in multivariate analysis. EGR2 mutations were recently reported in advanced stage CLL patients; thus, in paper III we screened 2403 CLL patients for mutations in EGR2. An overall mutational frequency of 3.8% was reported and EGR2 mutations were associated with younger age, advanced stage and del(11q). EGR2 mutational status remained an independent marker of poor outcome in multivariate analysis, both in the screening and validation cohorts. Whole-genome sequencing (WGS) of 70 CLL cases, assigned to poor-prognostic subsets #1 and #2 and indolent subset #4, were investigated in Paper IV and revealed a similar skewing of SF3B1 mutations in subset #2 and NOTCH1 mutations in subset #1 to that reported in Paper I. Additionally, an increased frequency of the recently proposed CLL driver gene RPS15 was observed in subset #1. Finally, novel non-coding mutational biases were detected in both subset #1 and #2 that warrant further investigation.

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