| 1. |
- Johansson, Bengt, 1958-
(författare)
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Long-term outcome research on PDR brachytherapy with focus on breast, base of tongue and lip cancer
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Brachytherapy (BT) with continuous low dose rate (LDR) has been used for 100 years and is considered as the radiotherapy method able to deliver a dose in the shortest time with high efficacy and low risk of side effects. The drawbacks are need for patient isolation and radiation exposure of the staff during the treatment. Brenner and Hall published the radiobiology concept for pulsed dose rate (PDR) in 1991. Short (10-20 minutes), hourly pulses of high dose rate (HDR) given to the same dose, with same overall treatment time will virtually simulate continuous LDR. At the same time new afterloading machine technology became available, where a single millimetre sized radiation 192Iridium source sequentially moves through the applicator in small individually timed steps. The advantages are that the radiation dose can be optimized along the applicator and with no radiation exposure of the staff and no need for patient isolation more than during the pulse. This work deals with four different aspects of PDR BT An experimental comparison of measured absorbed doses outside a left sided breast target on a body equivalent Alderson phantom was made. Five external beam radiotherapy (EBRT) whole breast treatments to 50 Gy versus five accelerated partial breast irradiations (APBI) by PDR BT to 50 Gy were studied. The absorbed doses were measured in 67 different positions inside the body phantom by thermoluminescence dosimeters. The result shows that dose points distant to the left breast will have 1-1.4 % of the prescribed dose with no difference between EBRT and PDR BT. Organs at risk in short distance (<5 cm) to the target (such as parts of the left lung, heart muscle and the right breast) will have significantly less dose by PDR BT. In conclusion PDR BT has dosimetric advantages close to the target compared to EBRT and cannot do more damage to remote organs. PDR APBI as the adjuvant RT treatment to breast conserving surgery after early breast cancer was studied. Between 1994-2004 we treated 50 women and 51 breasts. The median age of the population was 53 (40-72) years. The cases were radically resected, unifocal T1-2N0-1M0 tumours. PDR BT was given to a dose of 50 Gy for 5 days directed to the operated sector of the breast. The median treated volume was 160 cm3, constituting in median 31 % of the breast volume. The treatment is called accelerated because total treatment time is 5 days compared to 5 weeks for EBRT. After a median follow-up of 130 months (>10 years) we noted 5 (10 %) local recurrences in the treated breast. Four of these recurrences were outside the treated volume. Three women (6 %) developed cancers in the other breast. Early side effects were mild and less than with EBRT. As late side effects we found mild to moderate local fibroses in the treated volume. A cosmetic evaluation was done by both the patient and a nurse and was found to be lower than in other published data (56 % = good to excellent). The 10 years local failure rate is similar to the result from a large Swedish randomized study on whole breast radiotherapy to 50 Gy. The study indicates that PDR BT is highly effective. A combination of EBRT (40.8 Gy) and PDR boost (35 Gy) to T1-4N0-3M0, base of tongue (BOT) cancer, treated during 1994-2007 was analyzed. The study is the first with PDR and second largest with BT worldwide. A number of 83 patients with a median age of 60 (38-82) years were included. BT was given to a mean volume of 58 ccm 2 days after the neck dissection. Median follow-up was 54 months. At 5 years we found 89 % local tumour control, 95 % neck control, 80 % disease free survival and an overall survival of 65 %. Late side effects were 13 % minor transient soft tissue necrosis and 12 % long lasting or permanent soft tissue- or osteoradio-necrosis. The results are among the best published worldwide. An extensive quality of life analysis was done on 45 patients at last follow-up and showed limited, persistent xerostomia and dysphagia. The global quality of life was rated good in 75 % of the patients. The last study presented was PDR mono-brachytherapy (55-60 Gy) to cancer of the lip (T1-3N0M0). The study included 43 patients with a median age of 74 (37-92) years. The treatment time was 5.5-6 days and the mean treated volume was 15 ccm. The median follow-up time was 54 (1-158) months. Five year Kaplan-Meier data showed, local control 94 %, disease free survival 86 % and overall survival 59 %. An early side effect was a strong radiation mucositis and dermatitis, which healed in 1 month. Late side effects were uncommon and the cosmetic appearance and the lip function were found to be normal. Our data in total and per T-stage was compared to a European survey from 1993 on 2794 patients treated by LDR BT. The results are similar and are a strong indication of equal efficacy between PDR and LDR.
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| 2. |
- Karlsson, Kristin, et al.
(författare)
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Retrospective Cohort Study of Bronchial Doses and Radiation-Induced Atelectasis After Stereotactic Body Radiation Therapy of Lung Tumors Located Close to the Bronchial Tree
- 2013
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Ingår i: International Journal of Radiation Oncology, Biology, Physics. - : Elsevier BV. - 0360-3016 .- 1879-355X. ; 87:3, s. 590-595
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To evaluate the dose-response relationship between radiation-induced atelectasis after stereotactic body radiation therapy (SBRT) and bronchial dose. Methods and Materials: Seventy-four patients treated with SBRT for tumors close to main, lobar, or segmental bronchi were selected. The association between incidence of atelectasis and bronchial dose parameters (maximum point-dose and minimum dose to the high-dose bronchial volume [ranging from 0.1 cm(3) up to 2.0 cm(3)]) was statistically evaluated with survival analysis models. Results: Prescribed doses varied between 4 and 20 Gy per fraction in 2-5 fractions. Eighteen patients (24.3%) developed atelectasis considered to be radiation-induced. Statistical analysis showed a significant correlation between the incidence of radiation-induced atelectasis and minimum dose to the high-dose bronchial volumes, of which 0.1 cm(3) (D-0.1cm3) was used for further analysis. The median value of D-0.1cm3 (alpha/beta = 3 Gy) was EQD(2,LQ) = 147 Gy(3) (range, 20-293 Gy(3)). For patients who developed atelectasis the median value was EQD(2,LQ) = 210 Gy(3), and for patients who did not develop atelectasis, EQD(2,LQ) = 105 Gy(3). Median time from treatment to development of atelectasis was 8.0 months (range, 1.1-30.1 months). Conclusion: In this retrospective study a significant dose-response relationship between the incidence of atelectasis and the dose to the high-dose volume of the bronchi is shown.
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| 3. |
- Zackrisson, Björn, et al.
(författare)
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Two-year results from a Swedish study on conventional versus accelerated radiotherapy in head and neck squamous cell carcinoma - The ARTSCAN study
- 2011
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Ingår i: Radiotherapy and Oncology. - : Elsevier. - 0167-8140 .- 1879-0887. ; 100:1, s. 41-48
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Tidskriftsartikel (refereegranskat)abstract
- Background and purpose: Studies on accelerated fractionation (AF) in head and neck cancer have shown increased local control and survival compared with conventional fractionation (CF), while others have been non-conclusive. In 1998 a national Swedish group decided to perform a randomised controlled clinical study of AF. Materials and methods: Patients with verified squamous cell carcinoma of the oral cavity, oropharynx, larynx (except glottic T1-T2, N0) and hypopharynx were included. Patients with prior chemotherapy or surgery were excluded. Patients were randomised to either CF (2Gy/day, 5days/week for 7 weeks, total dose 68Gy) or to AF (1.1Gy+2.0Gy/day, 5days/week for 4.5weeks, total dose 68Gy). An extensive quality assurance protocol was followed throughout the study. The primary end point was loco-regional tumour control (LRC) at two years after treatment. RESULTS: The study was closed in 2006 when 750 patients had been randomised. Eighty-three percent of the patients had stages III-IV disease. Forty eight percent had oropharyngeal, 21% laryngeal, 17% hypopharyngeal and 14% oral cancers. There were no significant differences regarding overall survival (OS) or LRC between the two regimens. The OS at two years was 68% for AF and 67% for CF. The corresponding figures for LRC were 71% and 67%, respectively. There was a trend towards improved LRC for oral cancers treated (p=0.07) and for large tumours (T3-T4) (p=0.07) treated with AF. The AF group had significantly worse acute reactions, while there was no significant increase in late effects. Conclusion: Overall the AF regimen did not prove to be more efficacious than CF. However, the trend towards improved results in AF for oral cancers needs to be further investigated.
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| 4. |
- Aziz, Luaay, 1963, et al.
(författare)
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T but not N stage predicts survival for patients with tonsillar carcinoma treated with external radiotherapy and brachytherapy
- 2010
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Ingår i: Acta Oncologica. - : Informa UK Limited. - 0284-186X .- 1651-226X. ; 49:6, s. 821-825
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Tidskriftsartikel (refereegranskat)abstract
- Background. Our aim was to determine the efficacy of a therapeutic schedule including external radiation and brachytherapy in a consecutive and retrospective series of tonsillar carcinoma patients. Patients and methods. Ninety-six patients with tonsillar carcinoma were treated between 1988 and 2000 and were followed up for at least for three years. All patients were treated with accelerated hyperfractionated external radiotherapy, 68 patients had additional brachytherapy and 69 patients with advanced stages also received chemotherapy. There was no planned surgery even though 73% had N+ disease. Eleven patients with persistent neck nodes underwent ultimate salvage surgery. Results. The overall three-year survival (OS) was 70%. OS for the T stage was T1 90%, T2 89%, T3 54% and T4 60%. The corresponding numbers for the N stage were N0 61.5%, N1 73%, N2 78% and N3 66%. Accordingly OS was influenced by the T stage (p>0.001) rather than by N stage. Only four patients with salvage surgery had viable tumour cells in the specimen, their survival was not inferior. Discussion. The primary tumour stage is an essential determinant for survival in patients with irradiated tonsillar carcinoma. Neck dissection should be confined only as a salvage procedure.
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| 5. |
- Bergquist, Henrik, 1969, et al.
(författare)
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Combined stent insertion and single high-dose brachytherapy in patients with advanced esophageal cancer - results of a prospective safety study.
- 2011
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Ingår i: Diseases of the esophagus. - : Oxford University Press (OUP). - 1442-2050 .- 1120-8694. ; Early View
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Tidskriftsartikel (refereegranskat)abstract
- Previous randomized studies comparing the two commonly used palliative treatments for incurable esophageal cancer, i.e. stent insertion and intraluminal brachytherapy, have revealed the pros and cons of each therapy. While stent treatment offers a more prompt effect, brachytherapy results in more long-lasting relief of dysphagia and a better health-related quality of life (HRQL) in those living longer. This prospective pilot study aimed to explore the feasibility and safety of combining these two regimes and incorporating a single high dose of internal radiation. Patients with newly diagnosed, incurable cancer of the esophagus and dysphagia were eligible for inclusion, and stent insertion followed by a single dose (12Gy) of brachytherapy was performed as a two-stage procedure. Clinical parameters including HRQL and adverse events were registered at inclusion, and 1, 2, 3, 6, and 12 months later. Twelve patients (nine males) with a median age of 73 years (range 54-85) were included. Stent insertion followed by a single dose of brachytherapy was successfully performed in all but one patient who was treated with stent only. Relief of dysphagia was achieved in the majority of cases (10/11, P < 0.05), but HRQL did not improve except for dysphagia-related items. Only minor adverse events, including chest pain, reflux, and restenosis, were reported. The median survival time after inclusion was 6.6 months. Our conclusion is that the combination of stent insertion and single high-dose brachytherapy seems to be a feasible and safe palliative regime in patients with advanced esophageal cancer. Randomized trials comparing the efficacy of this strategy to stent insertion or brachytherapy alone are warranted.
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| 6. |
- Brämerson, Annika, 1960, et al.
(författare)
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Olfactory loss after head and neck cancer radiation therapy
- 2013
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Ingår i: Rhinology. - 0300-0729 .- 1996-8604. ; 51:3, s. 206-209
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: A reduced sense of smell may be one explanation for why patients with cancer in the ear, nose and throat (ENT) region who are treated with radiation therapy lose weight. The purpose of this study was to investigate whether radiation therapy has a negative effect on olfactory function and, if so, whether this effect is dose-related.METHODOLOGY: Seventy-one patients were tested using odour-detection sensitivity and olfactory identification tests before radiation therapy and 20 months after it.RESULTS: Patients who received radiation close to the olfactory organ showed a reduced sense of smell, in both tests. A multiple regression analysis showed that the radiation dose was related to decline in the olfactory function, while age, sex, chemotherapy and interactions between these variables were not.CONCLUSION: Radiation therapy can damage olfactory cells.
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| 7. |
- Franz, Jan, 1973, et al.
(författare)
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Formation of carbon-monoxide by radiative association : a quantum-dynamical study
- 2011
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 414, s. 3547-3550
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Tidskriftsartikel (refereegranskat)abstract
- Rate coefficients for the formation of carbon monoxide (CO) by radiative association of carbon and oxygen atoms are computed using quantum dynamical simulations. At temperatures above 10 K CO radiative association is dominated by C(3P) and O(3P) approaching on the A1Π potential energy curve. The rate coefficient is estimated as k=A(T/300 K)αexp−β/T with A= 1.39 × 10−18 cm3 s−1, α=−0.016 and β= 92.2 for temperatures between 6 and 127.2 K, and A= 1.36 × 10−17 cm3 s−1, α= 0.41 and β= 340 for temperatures between 127.2 and 15 000 K. Furthermore we computed the rate coefficients for approaching on the X1Σ+ curve. For temperatures below 200 K it is between 0.7 × 10−22 and 4 × 10−22 cm3 s−1.
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| 8. |
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| 9. |
- Franz, Jan, 1973, et al.
(författare)
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Molecule Formation by Radiative Association
- 2010
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Ingår i: The Chemical Cosmos: Understanding Chemistry in Astronomical Environments.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 10. |
- Franz, Jan, 1973, et al.
(författare)
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Molecule Formation in Interstellar Space
- 2010
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Ingår i: Department of Chemical- and Biological Engineering at Chalmers University of Technology and Chemistry at University of Gothenburg.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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