| 1. |
- Loftås, Per, 1964-
(författare)
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Response to neoadjuvant treatment in rectal cancer surgery
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- 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.
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| 2. |
- Näsvall, Pia, 1967-
(författare)
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Parastomal hernia : investigation and treatment
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- BackgroundParastomal hernia is a common stoma complication causing the patient considerable inconvenience. The patient becomes aware of a bulge around the stoma, but a bulge is not always a parastomal hernia and diagnostics must be performed to enable differential treatment. It is difficult to distinguish between a bulge and a hernia. Results based on clinical examination and computerised tomography (CT) in the supine position, have not been convincing. Three-dimensional intrastomal ultrasonography (3D US) is a novel technique shown to be promising in the assessment of stoma complaints. Two studies were performed to determine inter- and intra-observer reliability as well as the validity of 3D US as an alternative to CT when assessing stoma complaints.There are numerous options for the treatment of parastomal hernia, but none has been shown superior. In the recent decades the use of mesh in the repair of incisional and inguinal hernia has become routine. New materials must be evaluated as there are potential morbidity and even mortality risks with mesh repair. As recurrence of a parastomal hernia is an even greater challenge, the method of choice should have a low risk for recurrence. A prospective multicenter study was performed to evaluate safety and recurrence rate when using Parastomal Hernia Patch BARDTM (PHP), a mesh specially designed for parastomal hernia repair.A stoma has a profound impact on the patient´s daily life, both physical and psychological. A parastomal hernia with its associated risk for leakage and incarceration worsens the situation. Patient driven assessment of healthcare outcome is important if we are to improve medical care. A quality of life (QoL) survey was performed to assess the impact of parastomal bulging and hernia on the patient´s daily life.MethodsForty patients were investigated and the 3D US images were twice evaluated by two or three physicians to assess inter- and intra-observer reliability. Totally 20 patients with stoma complaints requiring surgery were examined with CT and 3D US prior to surgery. The findings were compared with the intraoperative findings – regarded as the true outcome.Fifty patients with parastomal hernia requiring surgery were enrolled from three hospitals. Patients were followed up one month and one year after repair using PHP.Patients still alive in 2008 who had been operated between1996 and 2004 for rectal cancer in Uppsala/Örebro-, Stockholm/Gotland-, and Northern Regions (986 patients) and registered in the Swedish Rectal Cancer Registry (SRCR) were invited to fill in four QoL questionnaires.ResultsInter-observer agreement using 3D US reached 80% for the last 10 patients examined, with a kappa value of 0.70. Intra-observer agreement for two examiners was 80% and 95%. The learning curve levelled out at 30 patients. Both CT and 3D US showed high sensitivity and specificity when compared with intraoperative findings.After surgery for parastomal hernia with a PHP, the complication rate at one month was 30% and recurrence rate at one year was 22%. Twelve patients were reoperated within one year.In the QoL study, 31.5% of the patients with a stoma reported a bulging or a hernia. 11.7% had been operated for parastomal hernia. A hernia or a bulge gave rise to significantly more pain and impaired stoma function. Overall QoL was inferior in patients with a permanent stoma compared to a group without a stoma.
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| 3. |
- Näverlo, Simon, 1991-
(författare)
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Stomas from a rural perspective : an evaluation of characteristics, differences and improvement opportunities
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: Stoma-related complications are common and consequences for the individual patient may be considerable. In rural areas, competence regarding stoma-related problems is largely absent. Since the aim of a publicly funded healthcare system is good healthcare on equal terms regardless of where one lives, studies evaluating differences and possible areas of improvement in rural areas are important. An evaluation of stoma-related characteristics, geographic differences and improvement opportunities from a rural perspective has not been done previously. The characteristics and differences studied in this thesis are: stoma reversal; occurrence of permanent stoma; and quality-of-life (QoL).Methods: Epidemiological methods applied to register data were used in Study I. Data extracted from the National Rectal Cancer Register together with socioeconomic data from Statistics Sweden were used. Study II was a cross-sectional study using surveys matched with data from the National Rectal Cancer Register. Study III was based on data from a double-blind randomised controlled trial. Patients were randomised to either a prophylactic mesh or no mesh in order to prevent parastomal hernia (PSH). Quality-of-life was assessed by grouping and comparing results of questionnaires answered by the patients included. In Study IV, a qualitative explorative method was applied to describe the quality of life of rural living stoma patients. Qualitative content analysis was used to analyse data.Aims and Results: Study I investigated whether distance by road to hospital had an impact on the following outcomes: stoma reversal rate; time from index operation to stoma reversal; and occurrence of permanent stoma after rectal cancer surgery. Longer distance to hospital had no effect on these outcomes in a multivariate model. In the univariate logistic regression model results indicated the opposite; patients living closest to the operating hospital had a higher likelihood of no reversal (OR 0.3; 95% CI 0.12–0.76). In northern Sweden, 77 % of all stoma reversals were delayed more than 6 months after index surgery. Stoma reversal was performed up to 1557 days after index surgery, and the shortest time to reversal was 82 days (median 287 days).Study II investigated the impact of distance to nearest hospital on the QoL of rectal cancer patients who had received a stoma at index surgery. Patients living in rural areas reported more pain and sore skin compared to those living closer. When only considering patients who still had a stoma, global QoL was reduced and stoma-related problems were also affected negatively in the rural group.Study III Investigated whether a prophylactic mesh when creating an end colostomy affected QoL. No effect on global QoL was seen at one-year follow up. In several other QoL-parameters mesh patients scored superior compared to non-mesh patients, even when excluding those with a parastomal hernia (PSH).Study IV investigated experiences of living with a stoma in a rural setting, how the process of seeking healthcare was experienced and the problems that occur. Results show that living with a stoma was experienced as a process; an initial sense of hopelessness, especially when suffering from stoma-related problems, progressing to the crucial acceptance of their situation. Stoma leakage was frequently described and experienced as unpleasant and unpredictable. Experiences of seeking healthcare in a rural district varied, some spoke warmly about the care given at the cottage hospital while other expressed dissatisfaction.Conclusions: The notably high rate of delayed reversal of a defunctioning stoma in northern Sweden leads to unnecessary suffering for patients. In view of the long delay in reversal times seen, future studies must have considerably longer follow-up. Rural living rectal cancer patients who receives a stoma reported more pain than those living closer to the nearest hospital. Rectal cancer patients who still had a stoma reported an inferior quality-of-life and more stoma-related problems compared to their town counterparts. Results from the studies in this thesis show that the use of a prophylactic mesh when forming an end colostomy has no impact on subsequent global QoL. Rural living stoma patients commonly experience problems related to their stoma that affect their everyday living. Improved patient education shortly after receiving a stoma could help these patients in coming to terms with their situation.
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| 4. |
- Syk, Ingvar
(författare)
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Systemic and Local Inflammatory Mediator Response to Major Surgery
- 2000
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cell-signalling via cytokines modulates the local response to surgical trauma, directs the immunologic response and initiates the healing process. Surgical trauma induces a systemic cytokine response and a down-regulation of the antigen presentation capacity of monocytes (HLA-DR expression), which is associated with a poor prognosis if pronounced. The aims with the studies in this thesis were to identify factors that modulate the cytokine and the immune-cell responses to major surgery and to evaluate the role of collagenases in colonic healing. Major surgery evoked a cytokine response in the systemic circulation, which was enhanced by the presence of a cancer, in colorectal resections. The IL-6 response in colorectal surgery originated from the bowel and enhanced concentrations of IL-6 in tissue of colorectal cancers, emanating from an IL-6 expression in the malignant epithelium, might be the source. Open surgery for abdominal aortic aneurysm (AAA) repair induced higher IL-6 responses than transfemorally placement of endoluminal grafts (TPEG), lower peri-operative sigmoidal pH but equal down-regulation of the HLA-DR expression on monocytes. These findings suggest that tissue destruction influences the systemic IL-6 response in trauma, but not the down-regulation HLA-DR expression on monocytes. Experimental colonic obstruction in rats implied a local inflammatory response and an increased break-down of collagen by matrix metalloproteinases in the colonic wall, leading to a decrease in collagen concentration, assessed as hydroxyproline concentration. Inhibition of MMPs in the early phase of anastomotic healing in the colon, resulted in increased breaking strength of the anastomoses in inhibitor-treated animals compared to controls, confirming a negative role of MMPs in this phase of colonic healing. The knowledge on cytokine response to surgical trauma and interactions with the healing process needs to be expanded by studies on local events in tissue. The information on collagenase up-regulation in the local inflammatory response in the colon and the results of MMP-inhibition in anastomotic healing are promising in the efforts to improve healing in colorectal surgery.
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| 5. |
- Van der Speeten, Kurt
(författare)
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A Pharmacokinetic and Pharmacodynamic Rationale for Perioperative Cancer Chemotherapy in Patients with Peritoneal Carcinomatosis
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Peritoneal carcinomatosis (PC) is a common manifestation of both gastrointestinal and gynecologic malignancies. Until recently, this condition was considered beyond curative intent treatment. Since the 1980s, new treatment strategies combining cytoreductive surgery (CRS) with perioperative intraperitoneal and intravenous chemotherapy have emerged. The underlying hypothesis considers CRS responsible for the removal of the macroscopic disease and that perioperative chemotherapy should address the residual microscopic disease. These new treatment regimens have presented encouraging clinical results that contrast with prior failure. The parameters for perioperative chemotherapy are mainly extrapolated from literature on peritoneal dialysis and data from systemic chemotherapy. The overall aim of this thesis was to provide a pharmacokinetic and pharmacodynamic rationale for perioperative intraperitoneal (IP) and intravenous (IV) chemotherapy in PC patients and, to assess its toxicity. After intraoperative IV administration of 5-fluorouracil or ifosfamide, substantial levels of these drugs were found inside the peritoneal fluid and tumor nodules (Papers I and II). This created a pharmacologically advantageous situation whereby a normothermic administered IV drug was subject to the effect of the local hyperthermia in the peritoneal fluid and tumor nodule. High levels of 5-fluouracil, ifosfamide and doxorubicin were observed inside the tumor nodules (Papers I, II and III) and, the identical pharmacokinetic advantage (expressed as Area Under the Curve (AUC) IP/IV ratios)) resulted in different drug levels of doxorubicin according to the density of the tumor nodules (Paper III). These data stressed the importance of pharmacodynamic variables such as tumor nodule density, size, and, vascularity. Therefore, the tumor nodule is proposed as a more appropriate pharmacological endpoint than AUC ratios. After IP Mitomycin C administration in PC patients with a contracted abdomen, mitomycin clearance from the abdomen decreased (Paper IV), which indicated these patients at risk of under-treatment. Consequently, these pharmacologic data indicate a change in dosimetry for these treatment protocols might be warranted according to the diffusion area. Although diffusional vectors are viewed the main driving force for these treatment protocols, only pharmacokinetic variables such as dose, volume and duration are considered. As pharmacodynamic variables are equally important in the pharmacological assessment of cytotoxic effect, the tumor nodule was proposed as the center of a new conceptual model (Paper I). Mitomycin C data on non-metabolizers ( Paper IV) indicated the cytotoxicity of these cancer chemotherapy protocols is at the level of the individual tumor nodules. The morbidity and mortality of a new bidirectional intraoperative chemotherapy regimen in PC patients was analyzed (Paper V) which provided a means for identifying subsets of patients at risk for increased toxicity. This thesis provides pharmacokinetic and pharmacodynamic guidance for improving perioperative chemotherapy treatment strategies in PC patients and reports its toxicity.
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