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Cai Grau

Publications and source records attributed to Cai Grau.

At least 19 recordsLinked to original sources
PubMed2006

Dose optimisation in single plane interstitial brachytherapy.

BACKGROUND AND PURPOSE: Brachytherapy dose distributions can be optimised by modulation of source dwell times. In this study dose optimisation in single planar interstitial implants was evaluated in order to quantify the potential benefit in patients. MATERIAL AND METHODS: In 14 patients, treated for recurrent rectal and cervical cancer, flexible catheters were sutured intra-operatively to the tumour bed in areas with compromised surgical margin. Both non-optimised, geometrically and graphically optimised CT -based dose plans were made. The overdose index (OI), homogeneity index (HI), conformal index (COIN), minimum target dose, and high dose volumes were evaluated. The dependence of OI, HI, and COIN on target volume and implant regularity was evaluated. In addition, 12 theoretical implant configurations were analyzed. RESULTS: Geometrical and graphical optimisation improved the dose plans significantly with graphical optimisation being superior. Graphically optimised dose plans showed a significant decrease of 18%+/-9% in high dose volume (p<0.001). HI, COIN, and OI were significantly improved from 0.50+/-0.05 to 0.60+/-0.05, from 0.65+/-0.04 to 0.71+/-0.04, and from 0.19+/-0.03 to 0.15+/-0.03, respectively (p<0.001 for all). Moreover, minimum target dose increased significantly from 71%+/-5% to 80%+/-5% (p<0.001). The improvement in OI and HI obtained by optimisation depended on the regularity of the implant, such that the benefit of optimisation was larger for irregular implants. OI and HI correlated strongly with target volume limiting the usability of these parameters for comparison of dose plans between patients. CONCLUSIONS: Dwell time optimisation significantly improved the dose distribution regarding homogeneity, conformity, minimum target dose, and size of high dose volumes. Graphical optimisation is fast, reproducible and superior to geometric optimisation.

Brachytherapy↗
PubMed2006

Smoking has a negative impact upon health related quality of life after treatment for head and neck cancer.

To examine the influence of smoking on observer based morbidity scores and patient assessed health related quality of life after treatment for head and neck cancer. The results of EORTC C30 and H&N35 questionnaires and DAHANCA morbidity scores were studied according to smoking status in 114 recurrence free head and neck cancer patients. In contrast to observer based toxicity scoring, smoking had a significantly negative influence on 20 of the 33 quality of life scales. Previous smokers had quality of life scores in between never smokers and continuous smokers. Smoking after treatment of head and neck cancer adversely influenced a wide range of quality of life endpoints. Quitters had better quality of life than patients who continued to smoke after treatment, suggesting that smoking cessation may improve quality of life in addition to reducing the risk of new cancer.

Adult↗
PubMed2006

Loco-regional recurrence after mastectomy in high-risk breast cancer--risk and prognosis. An analysis of patients from the DBCG 82 b&c randomization trials.

BACKGROUND AND PURPOSE: In the DBCG 82 b&c trials, 3,083 patients with stages II and III breast cancer were randomised to receive post-mastectomy radiotherapy (RT) versus no RT in addition to systemic therapy. The study showed a decrease in loco-regional recurrences and an improved survival in patients receiving RT. The aim of the present study was to identify risk factors for loco-regional recurrence (LRR), to evaluate the treatment of LRR and to examine the prognosis after LRR. PATIENTS AND METHODS: The 18-year probabilities of LRR were calculated for different prognostic factors using the Kaplan-Meier method. The efficacy of different LRR treatments was compared. The 5-year survival and distant metastases (DM) probability after LRR was calculated with regard to initial randomization group, primary tumor and recurrence related variables. RESULTS: Of the 3,083 patients, 535 had a LRR alone as first site of failure. In univariate analyses, large primary tumor size, ductal carcinoma, high malignancy grade, fascia invasion, few removed nodes, many positive nodes and extracapsular invasion were all risk factors for developing LRR. Combined treatment with surgery and RT at the time of LRR increased the persistent loco-regional control. The 5-year probability of subsequent DM was 73% irrespective of initial randomization group. In multivariate analysis, large primary tumor size, many positive nodes, extracapsular invasion, supra/infraclaviculary failures, multiple LRR and a short interval less than 2 years to first LRR were poor prognostic factors for survival. CONCLUSIONS: Twenty-seven percent of LRR patients had no DM 5 years after failure. Initial randomization group did not alter the prognosis after LRR. Combined treatment of the LRR with surgery and RT improved persistent loco-regional control compared with surgery or RT alone.

Adult↗
PubMed2006

Study of failure pattern among high-risk breast cancer patients with or without postmastectomy radiotherapy in addition to adjuvant systemic therapy: long-term results from the Danish Breast Cancer Cooperative Group DBCG 82 b and c randomized studies.

PURPOSE: Postmastectomy radiotherapy (RT) in high-risk breast cancer patients can reduce locoregional recurrences (LRRs) and improve disease-free and overall survival. The aim of this analysis was to examine the overall disease recurrence pattern among patients randomly assigned to receive treatment with or without RT. PATIENTS AND METHODS: A long-term follow-up was performed among the 3,083 patients from the Danish Breast Cancer Cooperative Group 82 b and c trials, except in those already recorded with distant metastases (DM) or contralateral breast cancer (CBC). The end points were LRR, DM, and CBC, and the follow-up continued until DM, CBC, emigration, or death. Information was selected from medical records, general practitioners, and the National Causes of Death Registry. The median potential follow-up time was 18 years. RESULTS: The 18-year probability of any first breast cancer event was 73% and 59% (P < .001) after no RT and RT, respectively (relative risk [RR], 0.68; 95% CI, 0.63 to 0.75). The 18-year probability of LRR (with or without DM) was 49% and 14% (P < .001) after no RT and RT, respectively (RR, 0.23; 95% CI, 0.19 to 0.27). The 18-year probability of DM subsequent to LRR was 35% and 6% (P < .001) after no RT and RT, respectively (RR, 0.15; 95% CI, 0.11 to 0.20), whereas the probability of any DM was 64% and 53% (P < .001) after no RT versus RT, respectively (RR, 0.78; 95% CI, 0.71 to 0.86). CONCLUSION: Postmastectomy RT changes the disease recurrence pattern in high-risk breast cancer patients; fewer patients have LRR as first site of recurrence, and overall fewer patients have DM.

Adult↗
PubMed2006

Individual radiation response of parotid glands investigated by dynamic 11C-methionine PET.

BACKGROUND AND PURPOSE: Previously, we showed that the net metabolic clearance of 11C-methionine of the parotid gland, K, calculated from dynamic 11C-methionine PET, can be used as a measure of parotid gland function. The aim of this study was to investigate by dynamic 11C-methionine PET the individual radiation dose response relationship of parotid glands in head and neck cancer patients. PATIENTS AND METHODS: Twelve head and neck cancer patients were examined by dynamic 11C-methionine PET after radiotherapy. Parametric images of K were generated, co-registered and compared voxel-by-voxel with the 3D radiation dose plan within the parotid gland to assess the individual radiation dose-function relationship. RESULTS: In each patient, voxel-values of K decreased with increasing radiation dose. Population based analysis showed a sigmoid dose response relationship of parotid gland, from which we estimated a threshold radiation dose of 16 Gy and a mean TD50 of 30 Gy. TD50 ranged from 7 to 50 Gy in the group of patients. CONCLUSIONS: Individual radiation dose response of parotid glands can be measured by dynamic 11C-methionine PET. The dose response analysis revealed a sigmoid relationship, a threshold radiation dose of 16 Gy, and a mean TD50 of 30 Gy.

Aged↗
PubMed2006

The relationship between observer-based toxicity scoring and patient assessed symptom severity after treatment for head and neck cancer. A correlative cross sectional study of the DAHANCA toxicity scoring system and the EORTC quality of life questionnaires.

BACKGROUND AND PURPOSE: Morbidity is an important issue in cancer research. The observer-based toxicity scoring system used by DAHANCA (the Danish head and neck cancer study group) has proved itself sensitive to differences in toxicity in a large randomised study, but like other toxicity scoring systems it has not been formally validated. Conversely, the EORTC quality of life questionnaire (QLQ) has been validated as a tool for collecting information about the consequences of disease and treatment on the well being of cancer patients. The purpose of this study was to examine the relationship between the two methods of side effect recording. PATIENTS AND METHODS: One hundred and sixteen recurrence free patients with laryngeal (n=44), pharyngeal (n=34) and oral cavity (n=38) cancer attending follow-up after radiotherapy (n=83) or surgery (n=33) completed EORTC C30, the core questionnaire concerning general symptoms and function and EORTC H&N35 the head and neck specific questionnaire. The attending physicians in the follow-up clinic evaluated and recorded DAHANCA toxicity scores on the same patients. RESULTS: The DAHANCA toxicity scoring system and the EORTC QLQ correlated with several clinical endpoints. The conceptually similar endpoints of the two methods correlated significantly. The objective endpoints of the DAHANCA scoring system were only correlated with quality of life endpoints to a very low degree. The DAHANCA toxicity scores had a low sensitivity (0.48-0.74) in detecting equivalent subjective complaints from the questionnaires and the observer-based scoring system severely underestimated patient complaints. A specific patient group where the DAHANCA score had a higher tendency to fail could not be detected. CONCLUSION: The DAHANCA toxicity score is an effective instrument in assessing objective treatment induced toxicity in head and neck cancer patients but insensitive and non-specific with regard to patient assessed subjective endpoints. This weakness seems inherent in an observer-based scoring system, and will probably also apply to newer ones like CTCAE 3.0.

Adult↗
PubMed2006

A cross sectional quality of life study of 116 recurrence free head and neck cancer patients. The first use of EORTC H&N35 in Danish.

The quality of life questionnaire EORTC C30 with the head and neck specific module H&N35 has been validated in many languages and cultural settings, but the H&N35 module has not been formally translated to and validated in Danish. This validation was the purpose of the current study. In a cross sectional study 116 of 120 (97%) recurrence free head and neck cancer patients returned a valid questionnaire. The patients were attending follow up after radical radiotherapy (n=83), surgery (n=33) for cancer of the larynx (n=44), pharynx (n=34) or oral cavity (n=38). The previously described psychometric properties of the questionnaire were confirmed with the Danish translation. Nevertheless, there were some foreseeable problems with heavily skewed endpoints. Several scales of the questionnaire were sensitive to patient, tumour and treatment related factors: Good performance, high age, male gender, laryngeal cancer, low tumour stage and surgery correlated with a low score on the symptom scales or high score on the function scales. Symptom intensity increased with time since therapy in patients who had surgery and decreased in the irradiated patients. In conclusion, the current validation study confirmed the psychometric properties of the EORTC H&N35 questionnaire. The questionnaire detected correlations between clinical factors (performance status, gender, age, stage, site, time since therapy, treatment) and a large number of QoL factors. EORTC H&N35 in conjunction with EORTC C30 is a valid and informative tool in assessing quality of life, also in Danish head and neck cancer patients.

Adult↗
PubMed2006

Changes from 1992 to 2002 in the pretreatment delay for patients with squamous cell carcinoma of larynx or pharynx: a Danish nationwide survey from DAHANCA.

In Denmark, a general impression of prolonged pretreatment delay for patients with head and neck cancer led to a nationwide study of time spans from symptom debut over first health care contact to start of treatment. Charts of consecutive new patients with squamous cell carcinoma of the pharynx and larynx, seen at the five Danish oncology centers in January-April 1992 and 2002, respectively, were reviewed. Of the 288 patients identified, definitive treatment was radiotherapy in 264 cases, surgery in one case. Twenty-three patients had neither surgery nor radiotherapy. Total time from first health care contact to start of definitive treatment was significantly longer in 2002 than in 1992 (median 70 versus 50 days, p<0.001). There was no significantly difference in time used for diagnosis. Time for treatment preparation and planning was 46 days in 2002 versus 31 days in 1992 (p<0.001). Significantly more diagnostic procedures (CT, MR, US, PET) were done in 2002. In conclusion, this nationwide study showed that waiting time before start of radiotherapy was significantly longer in 2002 compared to 1992. An increasing number of imaging procedures including CT-based dose planning was observed. The prolongation was mainly related to shortage of radiotherapy capacity. The three weeks extra pretreatment delay could theoretically lead to a 10% lower tumor control probability in 2002 compared to 1992.

Adult↗
PubMed2006

The Danish national guidelines for treatment of oral squamous cell carcinoma.

The treatment strategy for oral squamous cell carcinoma in Denmark has traditionally varied between the different head and neck oncology centres. A study group within the Danish Society for Head and Neck Oncology (DSHHO) was formed with the aim of optimising and standardising the treatment strategy. The approach was to use single modality treatment for stage I, stage II and some stage III and combined modality treatment for stage III and IV. Surgery was the preferred treatment when it was considered possible to perform a radical excision of the tumour and possible lymph node metastases with acceptable aesthetic and functional outcome. The implementation of a recognised national guideline facilitates prospective studies on a large well-characterised cohort. This increases the possibility of obtaining valid data on parameters such as morbidity, loco-regional control and survival. In addition the establishment of a reference program facilitates national monitoring of the treatment using defined indicators and standards.

Carcinoma, Squamous Cell↗
PubMed2006

Phase II study on stereotactic body radiotherapy of colorectal metastases.

Surgical resection provides long term survival in approximately 30% of patients with colorectal carcinoma (CRC) liver metastases. However, only a limited number of patients with CRC-metastases are amendable for surgery. We have tested the effect of stereotactic body radiotherapy (SBRT) in the treatment of inoperable patients with CRC-metastases. Sixty-four patients with a total number of 141 CRC-metastases in the liver (n = 44), lung (n = 12), lymph nodes (n = 3), suprarenal gland (n = 1) or two organs (n = 4) were treated with SBRT with a central dose of 15 Gy x 3 within 5-8 days. Median follow-up was 4.3 years. After 2 years, actuarial local control was 86% and 63% in tumor and patient based analysis, respectively. Nineteen percent were without local or distant progression after 2 years and overall survival was 67, 38, 22, 13, and 13% after 1, 2, 3, 4 and 5 years, respectively. One patient died due to hepatic failure, one patient was operated for a colonic perforation and two patients were conservatively treated for duodenal ulcerations. Beside these, only moderate toxicities such as nausea, diarrhoea and skin reactions were observed. SBRT in patients with inoperable CRC-metastases resulted in high probability of local control and promising survival rate. One toxic death and few severe reactions were observed. For the majority of patients, the treatment related toxicity was moderate.

Adult↗
PubMed2006

Aggravation of dyspnea in stage I non-small cell lung cancer patients following stereotactic body radiotherapy: Is there a dose-volume dependency?

In SBRT for NSCLC, highly potent radiation doses are delivered to patients with frequent pre-irradiatory compromise of pulmonary function. For the risk of pulmonary toxicity to be minimized during SBRT planning, data on its dose-volume dependency is needed. In the present study, we analyse the association of dose-volume histogram parameters with changes in dyspnea. The study concerns 28 medically inoperable stage I NSCLC patients that received SBRT at our department between 2000 and 2003. A central dose of 45 Gy/3 fractions was delivered in 5-8 days. WHO toxicity scoring of dyspnea was prospectively performed at baseline and during a 6-month follow-up post-SBRT. DVH parameters for pulmonary tissue were retrieved from the 3-D dose distributions. Aggravated dyspnea was registered in 11 patients (40%). We found no association between DVH parameters and changes in dyspnea. Nor did we find any consistent temporal variations of dyspnea after SBRT. We identified COPD as the factor showing the closest association with aggravation of dyspnea. The observed aggravation of dyspnea following SBRT reflects habitual exacerbations of COPD rather than treatment-related toxicity. Concern about pulmonary toxicity should not be prohibitive for future studies targeting limitations to dose and volume.

Aged↗
PubMed2005

Audit of the radiotherapy in the DBCG 82 b&c trials--a validation study of the 1,538 patients randomised to postmastectomy radiotherapy.

INTRODUCTION: In the DBCG 82 b&c trials 3083 patients with stages II and III breast cancer were randomised to receive postmastectomy radiotherapy (RT) versus no RT in addition to systemic therapy. The study showed a decrease in loco-regional recurrences and an improved survival in patients receiving RT. The aim of the present study was to describe the delivered RT for the 1538 patients who were randomised to RT, and to evaluate the compliance with the RT guidelines. PATIENTS AND METHODS: Basic information about the given RT was recorded in the DBCG data centre. For the current study, missing and additional information was collected from individual RT treatment charts. We defined some criteria for complying with the DBCG RT guidelines regarding target coverage and dose and fractionation and based on that we also defined some criteria for having clinically acceptable RT treatments. RESULTS: Of the 1538 patients, 87% received megavoltage RT, 8% had orthovoltage RT and 5% never began or completed RT. Of the 1341 megavoltage irradiated patients, the guideline compliance regarding target coverage of the axillary/periclaviculary region, internal mammary nodes and chest wall was 88, 79 and 85%, respectively. Only 0, 0.2 and 0.4% did not have clinically acceptable target coverage. The dose and fractionation was according to the guidelines in 96% and none had clinically unacceptable dose and fractionation schedules. CONCLUSION: The guideline compliance for megavoltage RT was high with 88, 79 and 85% complying with the guidelines regarding target coverage of the axillary/periclaviculary region, internal mammary nodes and chest wall, respectively, and with 96% complying with the guidelines regarding dose and fractionation schedules. Less than 1% had clinically unacceptable target coverage and none had unacceptable dose and fractionation schedules.

Adult↗
PubMed2004

11C-methionine PET, a novel method for measuring regional salivary gland function after radiotherapy of head and neck cancer.

BACKGROUND AND PURPOSE: Loss of salivary gland function is a distressing side-effect of radiotherapy (RT) for head and neck cancer. The aim of this study was to develop a positron emission tomography (PET) method for measuring regional salivary gland function in the major salivary glands irradiated during RT. PATIENTS AND METHODS: Eight head and neck cancer patients were included; two were examined before RT and six after parotid sparing RT. Patients were examined by dynamic 11C-methionine PET of the major salivary glands and parotid gland salivary flow measurements. PET data were analysed using a kinetic model of salivary gland 11C-methionine metabolism, in which salivary gland function was quantified by the net metabolic clearance of 11C-methionine, K. Functional voxel-wise images of K were calculated and matched with the CT-dose-plan for comparing regional salivary gland function with the regional radiation dose. RESULTS: Parotid gland K correlated positively with parotid gland salivary flow, indicating that K can be used as an index of salivary gland function. K of parotid and submandibular glands was reduced dependent on the median radiation dose. In one patient, receiving a heterogeneous radiation dose to the parotid glands, regional salivary gland function was inversely correlated to the regional radiation dose. CONCLUSIONS: Salivary gland function can be measured by dynamic 11C-methionine PET. The net metabolic clearance of 11C-methionine of salivary glands was reduced dependent on the radiation dose. Dynamic 11C-methionine PET offers a method for studying the individual response of the major salivary glands to irradiation.

Adult↗
PubMed2004

Nodal control and surgical salvage after primary radiotherapy in 1782 patients with laryngeal and pharyngeal carcinoma.

The purpose of this study was to evaluate the ultimate neck control after primary radiotherapy and surgical salvage in laryngeal and pharyngeal cancer patients. Some 1782 consecutive patients with squamous cell carcinoma were treated by radiotherapy. At presentation 26% of the patients had metastatic lymph nodes. A total of 298 primary or secondary nodal recurrences were seen, 159 were treated, and 53 (53/298 approximately 18%) were controlled. Isolated N-recurrence was fatal in 2.7% (36/1324) of the N0 patients. Univariate actuarial analysis of nodal control demonstrated that the region of origin, T-classification, T-size, N-classification, tumor stage, differentiation, hemoglobin, and radiation time were significant prognostic factors. In a Cox analysis the independent significant parameters were gender, region of origin, N-classification, and differentiation. The conclusions were that in patients with nodal recurrence a little over half were treated and of these a third of the nodal recurrences were controlled. Significant prognostic factors in multivariate analysis were gender, region of origin, N-classification, and tumor differentiation.

Adolescent↗
PubMed2003

Five compared with six fractions per week of conventional radiotherapy of squamous-cell carcinoma of head and neck: DAHANCA 6 and 7 randomised controlled trial.

BACKGROUND: Although head and neck cancer can be cured by radiotherapy, the optimum treatment time for locoregional control is unclear. We aimed to find out whether shortening of treatment time by use of six instead of five radiotherapy fractions per week improves the tumour response in squamous-cell carcinoma. METHODS: We did a multicentre, controlled, randomised trial. Between January, 1992, and December, 1999, of 1485 patients treated with primary radiotherapy alone, 1476 eligible patients were randomly assigned five (n=726) or six (n=750) fractions per week at the same total dose and fraction number (66-68 Gy in 33-34 fractions to all tumour sites except well-differentiated T1 glottic tumours, which were treated with 62 Gy). All patients, except those with glottic cancers, also received the hypoxic radiosensitiser nimorazole. Analysis was by intention to treat. FINDINGS: More than 97% of the patients received the planned total dose. Median overall treatment times were 39 days (six-fraction group) and 46 days (five-fraction group). Overall 5-year locoregional control rates were 70% and 60% for the six-fraction and five-fraction groups, respectively (p=0.0005). The whole benefit of shortening of treatment time was seen for primary tumour control (76 vs 64% for six and five fractions, p=0.0001), but was non-significant for neck-node control. Six compared with five fractions per week improved preservation of the voice among patients with laryngeal cancer (80 vs 68%, p=0.007). Disease-specific survival improved (73 vs 66% for six and five fractions, p=0.01) but not overall survival. Acute morbidity was significantly more frequent with six than with five fractions, but was transient. INTERPRETATION: The shortening of overall treatment time by increase of the weekly number of fractions is beneficial in patients with head and neck cancer. The six-fractions-weekly regimen has become the standard treatment in Denmark.

Adult↗
PubMed2003

Salvage laryngectomy and pharyngocutaneous fistulae after primary radiotherapy for head and neck cancer: a national survey from DAHANCA.

OBJECTIVE: In 1998, the Danish Society for Head and Neck Oncology decided to conduct a nationwide survey at the five head and neck oncology centers with the aim of evaluating the surgical outcome of salvage laryngectomy after radiotherapy with special emphasis on identifying factors that could contribute to the development of pharyngocutaneous fistulae. PATIENTS: A total of 472 consecutive patients undergoing postirradiation salvage laryngectomy in the period July 1, 1987-June 30, 1997 were recorded at the five head and neck oncology centers in Denmark. Age ranged from 36 to 84 years, median 63 years, 405 men and 67 women. Primary tumor site was glottic larynx (n = 242), supraglottic larynx (n = 149), other larynx (n = 45), pharynx (n = 27), and other (n = 9). All patients had received prior radiotherapy. RESULTS: Median time between radiotherapy and laryngectomy was 10 months (range, 1-348 months). A total of 89 fistulae lasting at least 2 weeks were observed, corresponding to an overall average fistulae risk of 19%. The number of performed laryngectomies per year decreased linearly (from 58 to 37), whereas the annual number of fistulae increased slightly (from 7 to 11), which meant that the corresponding estimated fistulae risk increased significantly from 12% in 1987 to 30% in 1997. Other significant risk factors for fistulae in univariate analysis included younger patient age, primary advanced T and N stage, nonglottic primary site, resection of hyoid bone, high total radiation dose, and large radiation fields. Multiple logistic regression analysis of these parameters suggested that nonglottic tumor site, late laryngectomy period (1987-1992 vs 1993-1997), and advanced initial T stage were independent prognostic factors for fistulae risk. Surgical parameters like resection of thyroid/tongue base/trachea or radiotherapy parameters like overall treatment time or fractions per week did not influence fistulae risk. CONCLUSIONS: The risk of fistulae is especially high in patients initially treated with radiotherapy for nonglottic advanced stage tumors. A significant decrease in the number of performed salvage laryngectomies over the 10 years was seen. Over the same time period, the annual number of fistulae remained almost constant. The resulting more than doubling of fistulae rate could thus in part be explained by less surgical routine.

Adult↗