Purpose To assess the impact of surgical margins status on local control in patients with primary early glottic (Tis-T2) squamous cell carcinoma after treatment with transoral CO2 laser... Show morePurpose To assess the impact of surgical margins status on local control in patients with primary early glottic (Tis-T2) squamous cell carcinoma after treatment with transoral CO2 laser microsurgery (TLM) and to assess the significance of additional wound bed biopsies.Methods Patients with Tis-T2 tumours treated with TLM type I-III resections according to the European Laryngological Society classification between 2009 and 2013 were included in retrospective analysis. Recurrence rate was determined in patients with free versus non-free specimen margins and wound biopsies. Five-year survival rates were determined using the Kaplan-Meier method. Prognostic impact of pT-category, resection margin status, tumour differentiation, wound bed biopsy status, and number of biopsies on local control (LC) were tested with the log-rank test.Results Eighty-four patients were included in the analysis. Positive margins were seen in 68 patients (81.0%). Margin status after TLM did not significantly influence LC (p = 0.489), however, additional wound bed biopsies were significantly associated with lower LC (p = 0.009). Five-year LC, disease-specific survival, overall survival and laryngeal preservation were 78.6, 78.0, 98.6 and 100%, respectively.Conclusions Additional wound bed biopsies can help predict local recurrence in patients treated with TLM for early glottic carcinoma. We propose that there is enough evidence to support a wait-and-see policy in patients with positive specimen margins and negative wound bed biopsies. For patients with positive wound bed biopsies, further treatment is warranted. Show less
Background Combining reirradiation (reRT) and hyperthermia (HT) has shown high therapeutic value for patients with locoregional recurrent breast cancer (LR). However, additional toxicity of... Show moreBackground Combining reirradiation (reRT) and hyperthermia (HT) has shown high therapeutic value for patients with locoregional recurrent breast cancer (LR). However, additional toxicity of reirradiation (e.g., rib fractures) may occur. The aim of this study is to determine the impact of potential risk factors on the occurrence of rib fractures.Patients and methods From 1982-2005, 234 patients were treated with adjuvant reRT + HT after surgery for LR. ReRT consisted typically of 8 fractions of 4 Gy twice a week, or 12 fractions of 3 Gy four times a week. A total of 118 patients were irradiated with abutted photon and electron fields. In all, 60 patients were irradiated using either one or alternating combinations of abutted AP electron fields. Hyperthermia was given once or twice a week.Results The 5-year infield local control (LC) rate was 70 %. Rib fractures were detected in 16 of 234 patients (actuarial risk: 7 % at 5 years). All rib fractures occurred in patients treated with a combination of photon and abutted electron fields (p = 0.000); in 15 of 16 patients fractures were located in the abutment regions. The other significant predictive factors for rib fractures were a higher fraction dose (p = 0.040), large RT fields, and treatment before the year 2000.Discussion and conclusion ReRT + HT results in long-term LC. The majority of rib fractures were located in the photon/electron abutment area, emphasizing the disadvantage of field overlap. Large abutted photon/electron fields combined with 4 Gy fractions increase the number of rib fractures in this study group. However, as these factors were highly correlated no relative importance of the individual factors could be estimated. Increasing the number of HT sessions a week does not increase the risk of rib fractures. Show less
This thesis consists of studies on stereotactic radiotherapy (SRT) of intracranial tumors aiming at optimizing the treatment technique and improving the patients__ outcome. We compared two... Show moreThis thesis consists of studies on stereotactic radiotherapy (SRT) of intracranial tumors aiming at optimizing the treatment technique and improving the patients__ outcome. We compared two treatment planning techniques (dynamic conformal arc and intensity-modulated radiotherapy) and concluded that for most patients optimal plans were possible with both techniques. We also found that patient fixation during SRT could be improved by adding a vacuum mouthpiece to the standard stereotactic frame. Five chapters deal with treatment results of SRT in patients with brain metastases. From our own results and a literature review we concluded that single fraction SRT produces excellent local control results in patients with small brain metastases, but insufficient local control rates in patients with large metastases. The higher biologically equivalent doses needed for improved local control rates in large brain metastases can be administered with fractionated SRT. Finally, we studied the clinical problem of lesion growth after SRT of brain metastases. The cause can be real tumor progression or pseudo-progression (radiation toxicity). We found that symptomatic pseudo-progression is serious radiation toxicity of the normal brain tissue surrounding the metastasis. Reduction of pseudo-progression rates is possible by limiting the volume of normal brain tissue that receives high radiation doses. Show less
Linthorst, M.; Baaijens, M.; Wiggenraad, R.; Creutzberg, C.; Ghidey, W.; Rhoon, G.C. van; Zee, J. van der 2015
Background and purpose: Randomized studies have shown that adding hyperthermia (HT) to re-irradiation (re-RT) improves treatment outcome for patients with breast cancer recurrences. We evaluated... Show moreBackground and purpose: Randomized studies have shown that adding hyperthermia (HT) to re-irradiation (re-RT) improves treatment outcome for patients with breast cancer recurrences. We evaluated the efficacy and side effects in patients treated with re-RT and HT for irresectable locoregional breast cancer recurrences.Material and methods: From September 1996 to December 2011, 248 patients with a macroscopic breast cancer recurrence were treated with re-RT and HT. Radiotherapy (RT) was applied to a dose of 32 Gy in 4 Gy fractions, twice weekly. HT was prescribed once weekly after RT. Primary endpoints for this analysis were complete response (CR) and local control (LC). Secondary endpoints were overall survival (OS), and toxicity. Patient-, tumor-, and treatment-related characteristics predictive for the endpoints were identified in univariate and multivariate analyses.Results: The median follow-up period was 32 months. The CR rate was 70%. At 1, 3, and 5 years LC was 53%, 40% and 39%, and OS was 66%, 32%, and 18%, respectively. OS after 10 years was 10%. Thermal burn developed in 23% patients, healing with conservative measures. The incidence of 5 years late grade 3 toxicity was 1%. A few patients survived more than 10 years without evidence of disease.Conclusions: The combination of re-RT and HT results in a high rate of long-term LC with acceptable late toxicity, and many patients remained locally controlled for the rest of their survival period. (C) 2015 Elsevier Ireland Ltd. All rights reserved. Show less
