T Warloe

Oslo University Hospital, Kristiania (historical), Oslo County, Norway

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Publications (48)119.84 Total impact

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    ABSTRACT: Extracorporeal photopheresis that exposes isolated white blood cells to 8-methoxypsoralen (8-MOP) and ultraviolet-A (UV-A) light is used for the management of cutaneous T-cell lymphomas and graft-versus-host disease. 8-MOP binds to DNA of both tumour and normal cells, thus increasing the risk of carcinogenesis of normal cells; and also kills both tumour and normal cells with no selectivity after UV-A irradiation. Hexaminolevulinate (HAL)-induced protoporphyrin-IX is a potent photosensitiser that localises at membranous structures outside of the nucleus of a cell. HAL-mediated photodynamic therapy selectively destroys activated/transformed lymphocytes and induces systemic anti-tumour immunity. The aim of the present study was to explore the possibility of using HAL instead of 8-MOP to kill cells after UV-A exposure.
    Biochimica et biophysica acta. 06/2014;
  • Sigrid I Kvaal, Trond Warloe
    Oral surgery, oral medicine, oral pathology and oral radiology. 02/2014; 117(2):257-8.
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    ABSTRACT: Genital erosive lichen planus (GELP) is a chronic inflammatory disease, in women characterized by painful vulvar and vaginal erosions. To prepare for a clinical trial on photodynamic treatment (PDT), we applied hexyl 5-aminolevulinate hydrochloride (HAL) in clinically normal and affected mucosa in 12 women with GELP using two different doses (6.25 or 50 mg/ml). Biopsies were taken after 30 minutes and 3 hours. The biodistribution of HAL, measured as photoactive protoporphyrin IX (PpIX), was studied using non-invasive superficial fluorescence measurements and microscopic fluorescence photometry. More PpIX was detected after application of 12.5 mg HAL than after 100 mg, with large inter-individual variations. PpIX levels after 3 hours were overall higher than after 30 minutes. PpIX fluorescence was not detected in skin distant to the genital area. In conclusion, 6.25 mg/ml HAL applied for 3 hours seems adequate for HAL absorption and conversion to PpIX in submucosal inflammatory and epithelial cells and can be used in a PDT trial of GELP.
    Photodiagnosis and photodynamic therapy 01/2014;
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    ABSTRACT: PURPOSE: To investigate whether a combination of self-expanding metal stent (SEMS) and brachytherapy provided more rapid and prolonged effect on dysphagia without increased pain compared to brachytherapy alone in patients with incurable oesophageal cancer. METHODS: 41 Patients were randomised to SEMS followed by brachytherapy, 8Gy×3 (n=21) or brachytherapy alone, 8Gy×3 (n=20). Change in dysphagia and pain three and seven weeks after randomisation (FU1 and FU2) was assessed by patient-reported outcome. Dysphagia, other symptoms and health-related quality of life were assessed every four weeks thereafter. The study was closed before the estimated patient-number was reached due to slow recruitment. RESULTS: Patients receiving SEMS followed by brachytherapy had significantly improved dysphagia at FU1 compared to patients receiving brachytherapy alone (n=35). Difference in pain was not observed. At FU2, patients in both arms (n=21) had less dysphagia. Four patients in the combined treatment arm experienced manageable complications, no complications occurred after brachytherapy alone. CONCLUSION: For the relief of dysphagia, SEMS followed by brachytherapy is preferable and safe for patients in need of immediate alleviation, while brachytherapy with or without preceding SEMS provides relief within a few weeks after treatment.
    Radiotherapy and Oncology 05/2013; · 4.52 Impact Factor
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    ABSTRACT: OBJECTIVES: The aim of this study was to examine the clinical behavior and response to topical methyl 5-aminolevulinate (MAL) photodynamic therapy (PDT) of oral lichen planus and to describe the buildup and biodistribution of photoactive porphyrins in normal and lichen planus-affected oral mucosa after MAL application. STUDY DESIGN: The difference in clinical expression in 14 patients with buccal oral lichen planus was compared before and after treatment. MAL-induced photoactive porphyrins were monitored using noninvasive in situ fluorescence measurements. Microfluorometry was used to study the biodistribution. RESULTS: The absorption and conversion of protoporphyrin IX (PpIX) in epithelial and subepithelial T cells was demonstrated in histologic sections. As a result of 1 treatment session, there was a significant improvement of oral lichen planus after 6 months (P = 0.02) and during a 4-year follow-up period. CONCLUSIONS: MAL is absorbed and converted to PpIX in T cells. Oral lichen planus treated with MAL-PDT showed lasting improvement after a single treatment.
    Oral surgery, oral medicine, oral pathology and oral radiology. 01/2013; 115(1):62-70.
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    ABSTRACT: In a retrospective review, in order to describe the palliative care and prognosis of patients with advanced cancer of the esophagus, the clinical characteristics and the treatment modalities applied were explored in relation to survival and symptom relief for 261 patients treated without curative potential. The data were obtained from a study of all patients with cancer of the esophagus treated at the Norwegian Radium Hospital in the 10-year period from 1990 to 1999. Medical data of the patients were reviewed and missing clinical information was retrieved from local hospitals and general practitioners. The patients were divided into three groups based upon the overall survival from start of treatment to death. Survival ≤3 months is in this paper, defined as 'short,' while survival > 6 months is defined as 'long.' Median survival for the total group of patients was 4 months. The 1-, 2-, and 3-year survival was 8%, 3%, and 1%, respectively. Patients with short survival (n= 107) had more advanced disease, lower performance status, and more dysphagia, weight loss, and pain and used more analgesics than patients with long survival (n= 91). Tumor characteristics such as localization, tumor length, and histology were not significantly associated with survival. This result was confirmed in a logistic regression analysis (with backward stepwise elimination) including sex, age, clinical stage, tumor length, tumor localization, histology, performance status, dysphagia, weight loss, and pain, where clinical stage, performance status, weight loss, and pain were included in the final model. A large variety of first-line palliative treatments were applied within the studied time period; external radiotherapy ± brachytherapy (n= 149), brachytherapy alone (n= 44), endoluminal stent (n= 28), laser evaporization (n= 8), chemotherapy (n= 5), and best supportive care only (n= 27). There were no clear differences in the effect on dysphagia between the modalities. Fourteen percent of the patients had treatment related complications. In conclusion, symptoms, performance status, and use of analgesics seemed to better prognosticate survival than tumor characteristics other than stage of disease. Our study reveals that knowledge about prognostic factors is crucial for the choice of palliative treatment. Even though all of the different treatment modalities seemed to provide relief of dysphagia, several other factors should be considered when deciding which treatment modality to offer. The time to onset of relief, duration of response, level of complications, and time spent in hospital should be a part of the decision-making process when selecting the appropriate treatment.
    Diseases of the Esophagus 02/2011; 24(7):502-9. · 1.64 Impact Factor
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    ABSTRACT: Over a 10-year period from 1990, 445 patients with carcinoma of the oesophagus were admitted to the Norwegian Radium Hospital and 184 of these patients received treatment with curative intent. Even though surgery is the treatment of choice for these patients, many of them suffer from medical conditions that increase the risk for postoperative mortality and morbidity. In a retrospective study, the effect of the curative treatment offered to patients was explored with a particular focus on patients unfit for surgery. Medical data of the 184 patients treated with curative intent were reviewed and additional clinical information was retrieved from local hospitals and general practitioners. Preoperative radiotherapy followed by surgery was the standard curative treatment for operable patients. Medically inoperable patients were offered radical split-course hyperfractionated radiotherapy followed by a brachytherapy boost. More than 50% (103/184) received non-surgical treatment only. Patients who received radical surgery (n = 81) were younger, had better performance status, less weight loss and dysphagia compared to patients treated with radical radiotherapy (n = 102). One patient received only photodynamic therapy. The 3-year survival was 29% for patients treated with radical surgery, and 8% for patients who received radical radiotherapy. The overall median crude survival for the two groups of patients were 20 months and seven months respectively. The hyperfractionated radiotherapy provided symptom relief without extensive toxicity and with a possibility for cure for patients with oesophageal cancer who are unfit for surgery and chemoradiotherapy. The literature supports the curative potential of high dose accelerated hyperfractionated radiotherapy even though the optimal radiotherapy regimen still needs to be explored.
    Acta oncologica (Stockholm, Sweden) 11/2009; 49(2):209-18. · 2.27 Impact Factor
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    ABSTRACT: Methyl aminolaevulinate photodynamic therapy is increasingly practiced in the treatment of actinic keratoses, Bowen's disease and basal cell carcinomas. This method is particularly suitable for treating multiple lesions, field cancerization and lesions in areas where a good cosmetic outcome is of importance. Good treatment routines will contribute to a favourable result. The Norwegian photodynamic therapy (PDT) group consists of medical specialists with long and extensive PDT experience. With support in the literature, this group presents guidelines for the practical use of topical PDT in non-melanoma skin cancer.
    Journal of the European Academy of Dermatology and Venereology 10/2009; 24(5):505-12. · 2.69 Impact Factor
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    ABSTRACT: Photodynamic therapy (PDT) using methyl aminolevulinate (MAL) is an effective first-line treatment for actinic keratoses. A reduced incubation period may have practical advantages. This study aims to evaluate the effect of incubation time (1 vs. 3 h), MAL concentration (160 mg/g vs. 80 mg/g) and lesion preparation in the setting of MAL-PDT for treatment of actinic keratosis (AK). Open, randomized, parallel-group multicentre study. Outpatient dermatology clinics. One hundred and twelve patients with 384 previously untreated AK. Most lesions (87%) were located on the face and scalp and were thin (55%) or moderately thick (34%). Lesions were debrided, and MAL cream (160 mg/g or 80 mg/g) was applied before illumination with red light (570-670 nm; light dose, 75 J/cm2). Patients were followed up at 2 and 3 months. Sixty patients (54%) were re-treated and assessed at 6 months. Complete lesion response rates 3 and 12 months after last treatment. For lesions on the face/scalp, lesion complete response rates were 78% for thin AK and 74% for moderately thick AK lesions after 1 h vs. 96% and 87% after 3 h incubation with MAL 160 mg/g. Lesion recurrence rates at 12 months after two treatments were similar [19% (3 of 16) with 1 h vs. 17% (3 of 18) with 3 h 160 mg/kg MAL-PDT] and lower than for 80 mg/g MAL-PDT (44-45%). MAL-PDT using a 1-h incubation may be sufficient for successful treatment of selected AK lesions.
    Journal of the European Academy of Dermatology and Venereology 06/2009; 23(5):550-5. · 2.69 Impact Factor
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    ABSTRACT: A significant change in the occurrence of oesophageal squamous cell carcinomas (SCCs) in relation to adenocarcinomas (ACs) has been observed in the Norwegian population during the last 20 years (1988-2007). The AC incidence has increased from 5-10% to more than 50% nowadays, while the incidence of SCCs has decreased. Our goal was to evaluate if the change from SCC to AC and the increased effort to control reflux could be reflected in tumour stage, patient demographics and treatment results. We analysed clinical and pathological data from 347 patients with oesophageal AC (n = 189) and SCC (n = 158) treated at The Norwegian Radium Hospital during said period for patient- and tumour characteristics, treatment modalities and survival. An oesophageal resection was performed in 169 of 347 patients. The median survival rate for all patients was 15 months, with a 5-year survival rate of 10%. The median survival time for operated and non-operated patients was 25 and 12 months respectively, with the corresponding 5-year survival rate of 13% and 2%. Patients with N0M0 disease operated with free resection margins presented a 5-year survival rate of 28%. The change from SCC to AC and the ensuing considerable efforts made in surveillance and treatment of AC did not lead to improved long time survival for our patients.
    Scandinavian journal of surgery: SJS: official organ for the Finnish Surgical Society and the Scandinavian Surgical Society 01/2009; 98(4):214-20. · 1.17 Impact Factor
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    ABSTRACT: Long-term follow-up data are needed to evaluate treatment effect after photodynamic therapy (PDT). To investigate long-term clinical, histological and cosmetic follow-up results in basal cell carcinoma (BCC) after PDT, including treatment response related to patients and lesion characteristics. A longitudinal study of 44 patients with 60 histologically verified BCC tumours, treated with one or two sessions of dimethylsulfoxide (DMSO)-supported 5-aminolaevulinic acid--PDT following curettage, was performed. Lesions in complete remission after 3 months were followed with clinical inspection, histological investigation and evaluation of cosmetic outcome at regular intervals; long-term efficacy assessed as verified recurrence within 72 months after PDT. Complete remission at 3 months was achieved in 55 lesions from 39 patients. Two patients with one lesion each died. At 72 months, 43 of 53 lesions remained disease-free (81%); 68% remained after one treatment session, and 91% remained after two treatment sessions. Recurrence of tumour occurred at 6, 12, 24 and 36 months in 2, 4, 2 and 2 lesions, respectively; clinical investigation identified 97% of them. Male sex and H-mid-face zone were significantly associated with recurrence. The cosmetic outcome at 72 months was rated as good or excellent by patients and investigators in more than 90% of evaluated cases. DMSO-PDT following curettage is an effective treatment for BCC, with favourable long-term clinical, histopathological and cosmetic results. Clinical examination of treated lesions appears to be sufficient for long term follow up.
    Journal of the European Academy of Dermatology and Venereology 10/2008; 23(1):58-66. · 2.69 Impact Factor
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    ABSTRACT: It is hard to imagine that a narrow, one-way, coherent, moving, amplified beam of light fired by excited atoms is powerful enough to slice through steel. In 1917, Albert Einstein speculated that under certain conditions atoms could absorb light and be stimulated to shed their borrowed energy. Charles Townes coined the term laser (light amplification by stimulated emission of radiation) in 1951. Theodore Maiman investigated the glare of a flash lamp in a rod of synthetic ruby, creating the first human-made laser in 1960. The laser involves exciting atoms and passing them through a medium such as crystal, gas or liquid. As the cascade of photon energy sweeps through the medium, bouncing off mirrors, it is reflected back and forth, and gains energy to produce a high wattage beam of light. Although lasers are today used by a large variety of professions, one of the most meaningful applications of laser technology has been through its use in medicine. Being faster and less invasive with a high precision, lasers have penetrated into most medical disciplines during the last half century including dermatology, ophthalmology, dentistry, otolaryngology, gastroenterology, urology, gynaecology, cardiology, neurosurgery and orthopaedics. In many ways the laser has revolutionized the diagnosis and treatment of a disease. As a surgical tool the laser is capable of three basic functions. When focused on a point it can cauterize deeply as it cuts, reducing the surgical trauma caused by a knife. It can vaporize the surface of a tissue. Or, through optical fibres, it can permit a doctor to see inside the body. Lasers have also become an indispensable tool in biological applications from high-resolution microscopy to subcellular nanosurgery. Indeed, medical lasers are a prime example of how the movement of an idea can truly change the medical world. This review will survey various applications of lasers in medicine including four major categories: types of lasers, laser-tissue interactions, therapeutics and diagnostics.
    Reports on Progress in Physics 04/2008; 71(5):056701. · 13.23 Impact Factor
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    ABSTRACT: Fluorescence diagnosis following oral administration of 5-aminolevulinic acid (5-ALA) has shown to enable the sensitive visualization of intestinal metaplasia, dysplasia and early carcinoma in Barrett's esophagus. Once being established, this technique will be a potential alternative to today's standard diagnosis, i.e. four-quadrant random biopsies which are taken every 1-2 cm of the esophagus for histopathological analysis. In order to further improve this methodology, topical application of lipophilic 5-ALA esters to the esophagus could be advantageous in terms of fluorescence contrast and fluorescence intensity in the target tissue, adverse side effects, as well as application time. Therefore, the aim of this study was to develop a bioadhesive formulation loaded with hexylaminolevulinate (HAL) targeting the esophageal lining. In the present study, different mucoadhesive gels including poloxamer 407, cross-linked polyacrylic acid, hydroxypropylmethylcellulose, sodium carboxymethylcellulose and chitosan have been evaluated with respect to bioadhesion to the esophagus using an ex vivo rat model and a clinical study on healthy volunteers. In order to visualize the mucoadhesive properties of the formulations, a blue dye was incorporated as contrast agent. Chitosan has shown the best esophageal adhesion both in vitro and in vivo. Furthermore, using the in vitro release profiles from chitosan loaded with 40 mM of HAL, one can estimate that after a residence time of 10 min on the esophageal wall, the amount of HAL delivered to the epithelium will be sufficient to perform fluorescence diagnosis of Barrett's esophagus following swallowing of this formulation.
    Journal of Controlled Release 12/2007; 123(3):203-10. · 7.63 Impact Factor
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    ABSTRACT: The aim of this prospective randomized study was to compare the clinical and cosmetic outcome of superficial basal cell carcinomas (BCC), using either laser or broadband halogen light, in photodynamic therapy with topical 5-aminolevulinic acid (ALA). A total of 83 patients with 245 superficial BCC were included in the study. Standard treatment involved 15 min of local pretreatment with 99% dimethylsulfoxide (DMSO) before topical application of 20% ALA with DMSO (2%) and ethylendiaminetetraacetic acid (2%) as cofactors for 3 h before light exposure with either laser or a broadband lamp (BL). A complete response was achieved in 95 lesions (86%) in the laser group and 110 lesions (82%) in the BL group 6 months after treatment. Of these, 80 lesions (84%) in the laser group and 101 lesions (92%) in the lamp group were independently evaluated to have an excellent or good cosmetic post-treatment score. No serious adverse events were reported. This study shows that there is no statistical significant difference in cure the rate (P= 0.49) and the cosmetic outcome (P= 0.075) with topical application of a modified ALA-cream between light exposure from a simple BL with continuous spectrum (570–740 nm) or from a red-light laser (monochromatic 630 nm). Cost and safety are further elements in favor of the BL in this setting.
    Photochemistry and Photobiology 04/2007; 71(6):724 - 729. · 2.29 Impact Factor
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    ABSTRACT: Urinary bladder urothelial carcinoma is diagnosed by a combination of cystoscopy and biopsy, with cytology as a valuable additional technique. The accuracy of cytological diagnosis depends on the experience of the cytologist and can inevitably vary from one cytologist to another. There is a need for an easy, reliable and objective diagnostic method. In the present study a new method was designed for the detection of bladder cancer cells in urine. Flow cytometry was utilized to detect protoporphyrin IX in an artificial model consisting of normal urinary bladder transitional epithelial cells (NBECs) from healthy volunteers' urine and an established human urinary bladder carcinoma cell line, TCCSUP, after incubation with hexaminolevulinate (HAL). In addition, urine samples from 19 patients with histopathologically confirmed superficial bladder cancer were examined. Incubation of NBECs or TCCSUP cells with HAL for 1 hour resulted in production of protoporphyrin IX only in the TCCSUP cells. Incubation of a mixture of NBECs and TCCSUP cells with HAL gave rise to a separated subpopulation of cells with protoporphyrin IX fluorescence. After cell sorting by flow cytometry the protoporphyrin IX-containing subpopulation of cells was confirmed as TCCSUP cells on cytological examination. It was possible to detect 5% TCCSUP cells in the mixture of NBECs/TCCSUP cells. To test the feasibility of the method in clinica diagnosis, urine samples from patients with bladder cancer were also measured with comparable, although preliminary and limited, results to those of cytological examination. The preliminary results show that the technique may be feasible for the detection of bladder cancer cells in urine with possible advantages of simplicity, reliability and objectivity.
    Cytopathology 04/2007; 18(2):87-95. · 1.71 Impact Factor
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    ABSTRACT: Photodynamic therapy using topical methyl aminolaevulinate (MAL) is a new treatment modality for skin disorders. MAL is metabolized into endogenous porphyrins, which act as photosensitizers when illuminated. To evaluate the severity and duration of skin photosensitivity after MAL application, and to investigate its relation to the presence of endogenous porphyrins. Placebo and 160 mg g(-1) MAL creams were randomly assigned to contralateral sites located at the forearms and fingertips of 16 healthy volunteers and were applied for 3 h. The porphyrin content in the skin was monitored by in situ fluorescence measurements following cream removal. Phototoxic reaction was evaluated after exposure to a high dose of red light. The porphyrin fluorescence in forearm skin peaked about 1 h after the cream removal, was halved after 8 h, and was reduced by > 90% within 24 h. Most forearm sites were photosensitive at 1 and 8 h following cream removal. Six subjects were still sensitive at 24 h, and at this time point the phototoxicity was coincidental with residual porphyrin fluorescence. In general, all reactions were mild or moderate, and included pain, erythema, oedema and transient hyperpigmentation. No photosensitivity or porphyrin fluorescence was detected at 48 h. At the fingertips photosensitivity was absent except for sporadic cases of mild pain. Topical MAL application and exposure to red light induced mild and moderate phototoxicity. The photosensitivity ceased within 24-48 h after cream removal, and its duration was associated with the degradation of porphyrins.
    British Journal of Dermatology 03/2007; 156(2):301-7. · 3.76 Impact Factor
  • Sigrid I Kvaal, Trond Warloe
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    ABSTRACT: Photodynamic treatment (PDT) was first started in the oral cavity in the mid 1980s. Hematoporphyrins were rapidly replaced by Photofrin and meta-tetrahydroxyphenylchlorin (mTHPC) as photosensitisers of choice, and over the years these two have been approved by several health authorities for PDT. 5-aminolevulinic acid (ALA) and some dyes (e.g., toluidine and methyene blue) have also been tested. Several different nonthermal lasers have been used and lately light-emitting diodes (LEDs) have been tried. Most of the clinical treatments have been carried out on oral squamous cell carcinoma (OSSC), either primary or metastatic lesions, with good results. The treatment leaves little scarring and can be used before, in conjunction with, and adjunctive to other treatment modalities. The greatest disadvantage is that the patients are photosensitive for several weeks following systemic administration of the photosensitiser. PDT is now an accepted palliative treatment. Systemic administration of ALA has been more successful than local application in the treatment of precancerous lesions such as oral leukoplakia. PDT following topical application of photosensitiser (metylene blue and methyl-ALA) has shown improvement in cutaneous diseases of the oral mucous membrane such as oral lichen planus. The bactericidal effect of PDT has also been tested on oral plaque, but little clinical work has been performed so far. Instead of mechanical cleaning or antibiotic therapy, PDT may also play a role in dental diseases.
    Journal of Environmental Pathology Toxicology and Oncology 02/2007; 26(2):127-33. · 0.92 Impact Factor
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    ABSTRACT: Photodynamic therapy (PDT) has been investigated as an alternative treatment for cutaneous squamous cell carcinoma in situ (CIS), also known as Bowen's disease. Atypia of the squamous epithelium is graded, with the most severe atypia being equivalent to CIS. CIS on the penis is regarded as a premalignant condition and is seen either in isolation or in conjunction with carcinoma of the penis. A group of 10 patients with atypia/CIS were treated with PDT between December 2002 and April 2005. The group consisted of five patients with primary lesions and five with atypia after an organ-preserving operation for carcinoma of the penis. Eight patients were treated once, one twice and one six times. When complete remission was not achieved, a biopsy was taken for diagnosis. Three of the 10 patients had histopathological residual disease after a median follow-up period of 20 months (range 15-36 months). The first week after treatment could be painful but the cosmetic results were excellent. There was almost no loss of substance or fibrosis in the treated area, and sensitivity was restored to normal after approximately 1 month. In our experience, PDT for CIS seems to be a promising treatment modality with regard to cancer control, organ preservation, cosmetics and functional results. As with laser therapy of these lesions, careful follow-up is mandatory. Larger studies are needed and are planned.
    Scandinavian Journal of Urology and Nephrology 02/2007; 41(6):507-10. · 1.01 Impact Factor
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    ABSTRACT: The undersigned, who are co-authors of the article Diagnostics and treatment of early stages of oral cancer, wish to retract it. The reason is that the basis for the review article has been shown to be false. A review committee, that has assessed the research activity of the main author, has concluded that the data in this article are fabricated. We can no longer stand behind the article and hereby retract it.
    Tidsskrift for den Norske laegeforening 10/2006; 126(17):2287.
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    ABSTRACT: Photodynamic therapy using topical methyl 5-aminolevulinate (MAL) is a new treatment modality for basal cell carcinoma (BCC) and actinic keratosis (AK). MAL induces endogenous porphyrins, which act as photosensitizers. Pharmacokinetic studies of the porphyrin-inducing effect of MAL creams (Metvix) applied in different concentrations (16-160 mg/g) and application times are presented. Surface fluorescence measurements were used to monitor porphyrin accumulation in 18 superficial BCCs and 32 AKs. For both lesion types, the fluorescence increased during the first 13 of 28 hours of continuous MAL application. A 20-fold site-to-site variation was observed, and there were no significant MAL concentration dependencies. The selectivity between lesions and normal skin was 10-fold during the first hours and decreased throughout the application time. Fluorescence microscopy images of tissue sections from 32 nodular BCCs were analyzed to calculate the porphyrin content in tumor tissue as a function of depth. Significant correlation to MAL concentration was seen within the tumors treated for 3 hours. Increase to 18-hour MAL application enhanced the fluorescence levels in superficial tumor layers, but not in deep layers. In conclusion, application of the 160 mg/g cream for 3 hours gave advantageous porphyrin distributions for all types of lesions.
    Journal of Investigative Dermatology 03/2006; 126(2):265-71. · 6.19 Impact Factor

Publication Stats

1k Citations
119.84 Total Impact Points

Institutions

  • 2014
    • Oslo University Hospital
      • Department of Pathology
      Kristiania (historical), Oslo County, Norway
  • 1997–2013
    • University of Oslo
      • • Institute of Clinical Dentistry
      • • Department of Pathology (PAT)
      • • Faculty of Dentistry
      Oslo, Oslo, Norway
  • 2009
    • Karolinska University Hospital
      Tukholma, Stockholm, Sweden