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Featured researches published by Jens Bentzen.


The Lancet | 2003

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

Jens Overgaard; Hanne Sand Hansen; Lena Specht; Marie Overgaard; Cai Grau; Elo Andersen; Jens Bentzen; Lars Bastholt; O. Hansen; Jørgen Johansen; Lisbeth Juhler Andersen; Jan F. Evensen

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.


Acta Oncologica | 2010

Carcinoma of the nasal cavity and paranasal sinuses in Denmark 1995-2004

Christian Thorup; Lars Sebbesen; Hella Danø; Michael Leetmaa; Mette Andersen; Christian von Buchwald; Claus A. Kristensen; Jens Bentzen; Christian Godballe; Jørgen Johansen; Cai Grau

Abstract Objective. To evaluate the treatment outcome for sino-nasal carcinomas in Denmark from 1995–2004 and compare the results to the previous Danish survey covering 1982–1991. Design. Retrospective follow-up. Materials and methods. In the five Danish head and neck oncology centres, charts of all consecutive patients with sino-nasal carcinomas were reviewed and data extracted to a common database. Altogether 242 patients from the period 1995–2004 were identified. Of these 162 (67%) were male and 80 (33%) female. Histologies included squamous cell carcinoma (55%), adenocarcinoma (28.5%), adenoid-cystic carcinoma (5.0%), undifferentiated carcinoma (4.5%), transitiocellular carcinoma (1.7%), mucoepidermoid carcinoma (0.8%), neuroendocrine carcinoma (2.5%), small cell carcinomas (1.2%) and carcinomas not otherwise specified (0.8%). Treatments included radiotherapy alone 79 (33%), surgery alone 29 (12%), combined surgery and radiotherapy 96 (40%), palliative/no treatment 38 (16%). A total of 204 (86%) patients were treated with curative intent. Results. Of the 204 patients treated with curative intent, 94 (46%) relapsed. Most failures were in T-site (63, 30%). N-site failures were 10 (5%) and M-site failures six (3%). Failure occurring in T+N-site, T+M-site, N+M-site and T+N+M-site were seven (3%), two (1%), one (0.5%) and five (3%) respectively. The 5-year actuarial local, nodal and loco-regional control rates were 55±4%, 86±3%, 49±4%, respectively. The overall 5-year actuarial survival rate for the entire cohort was 47±3%, and the corresponding cancer-specific 5-year actuarial survival rate was 57±3%. Female gender, nasal cavity tumour, adenocarcinoma and low clinical stage were significant positive prognostic factors in univariate analysis. A Cox multivariate analysis showed that only tumour site and clinical stage were independent significant prognostic factors. Conclusion. The current series has confirmed stage and tumour site as independent prognostic factors. Compared to the previous Danish survey covering the period 1982–1991, the overall survival and cancer-specific survival rates have improved significantly.


Acta Oncologica | 2015

Locally advanced head and neck cancer treated with accelerated radiotherapy, the hypoxic modifier nimorazole and weekly cisplatin. Results from the DAHANCA 18 phase II study

Jens Bentzen; Kasper Toustrup; Jesper Grau Eriksen; Hanne Primdahl; Lisbeth Juhler Andersen; Jens Overgaard

Abstract Purpose/Objective. A phase II clinical trial evaluating the feasibility and outcome of treating locally advanced head and neck squamous cell carcinoma (HNSCC) with accelerated radiotherapy, the hypoxic modifier nimorazole and weekly cisplatin. Material and methods. A total of 227 patients with stage III or IV HNSCC of the larynx, oropharynx, hypopharynx, or oral cavity where included between January 2007 and December 2010. The prescribed radiotherapy (RT) dose was 66–68 Gy in 2 Gy fractions, 6 F/W. The hypoxic radiosensitiser nimorazole was given orally at a dose of 1200 mg/m2 before each fraction. Concomitant cisplatin (40 mg/m2) i.v. was given once a week for a maximum of six cycles. Outcome data were evaluated in terms of loco-regional tumour control (LRC), event-free survival (EFS) and overall survival (OS). Morbidity data were evaluated based on the DAHANCA routine registration. Human papillomavirus (HPV)-status was estimated by immunohistochemical staining of p16. Results. Included were 178 (78%) men and 49 (22%) women with a median age of 57 years. All except five patients received RT as prescribed. At least five series of cisplatin was given to 164 (72%) of the patients, and 149 patients (66%) received the full dose of nimorazole. The five-year actuarial LRC, EFS and OS rates were 80%, 67% and 72%, respectively. The LRC rates according to site were: oropharynx: 88%, larynx: 77%, hypopharynx 72% and oral cavity 49%, respectively. HPV/p16 staining was obtained in 141 of the 150 oropharyngeal cancers. Of these, 112 (79%) were p16 pos and 29 (21%) were p16 neg. LRC for the p16 neg oropharyngeal cancers was poorer than for the p16 pos (74% vs. 91%; p = 0.02). Tube feeding during treatment was necessary for 146 (64%) patients. At 12 months this number was reduced to 6%. Conclusion. The treatment was tolerable in this cohort of locally advanced HNSCC patients. Acute and late toxicity was comparable to similar studies of chemoradiotherapy, and the outcome superior to the data reported in the literature. This strongly indicates that RT of advanced head and neck cancer must include as well hypoxic modification, accelerated fractionation as chemoradiotherapy to yield optimal outcome.


Thyroid | 2013

Papillary Thyroid Microcarcinoma in Denmark 1996–2008: A National Study of Epidemiology and Clinical Significance

Stefano Christian Londero; Annelise Krogdahl; Lars Bastholt; Jens Overgaard; Waldemar Trolle; Henrik Baymler Pedersen; Jens Bentzen; Sten Schytte; Peer Christiansen; Christian Godballe

BACKGROUND With an observed general rise in papillary thyroid carcinoma incidence, papillary microcarcinoma (PMC) is accordingly found more frequently and often incidentally by histological examination of surgical specimens from presumed benign thyroid disease. Only a few studies have specifically addressed the prognosis of incidentally found PMC, and they have been limited to retrospective single-center studies. METHODS This was a national, unselected, prospective cohort study of 406 papillary thyroid microcarcinoma patients diagnosed in Denmark from 1996 to 2008. OBJECTIVE The aim of this study was to evaluate incidence, outcome, and extent of necessary treatment, with special attention given to incidentally detected PMC. RESULTS Age-standardized ratios were found to increase from 0.35 per 100,000 per year in 1996 to 0.74 per 100,000 per year in 2008. A total of 240 out of 406 cases were found incidentally, and a significant rise in incidence was only found for the incidental cases. Median follow-up was 7.6 years for the incidental cases, and in this time span, five cases of recurrence and no deaths from thyroid cancer occurred. The five-year recurrence-free survival was 98.1%, and only occurrence of lymph-node metastasis was found to affect the recurrence rate. A total of 160 incidental cases were initially treated with lobectomy, and the incidence of recurrence was not significantly different in the cases receiving completion thyroidectomy. CONCLUSION The rising incidence of PMC in Denmark is explained by incidental cases. When the carcinoma is not the index tumor for surgery, this study implies that completion thyroidectomy does not improve prognosis.


Cancer Epidemiology | 2013

Papillary thyroid carcinoma in Denmark 1996-2008: An investigation of changes in incidence

Stefano Christian Londero; Annelise Krogdahl; Lars Bastholt; Jens Overgaard; Henrik Baymler Pedersen; Thomas Frisch; Jens Bentzen; Peter Ulrik Pedersen; Peer Christiansen; Christian Godballe

BACKGROUND A rise in the incidence of thyroid cancer has been reported in several countries, and the increase is only seen in the papillary type. Increased detection due to higher resolution ultrasound and fine needle aspiration has been proposed as the explanation, recent registry studies however question this assumption. METHODS National, unselected, prospective cohort study of 1350 papillary thyroid cancer patients in Denmark from 1996 to 2008. OBJECTIVE To analyze changes in incidence by time and to identify factors which might influence detection rate. RESULTS A rise in incidence is seen with age standardized ratios increasing from 1.43 per 100.000 per year in 1996 to 2.16 per 100.000 per year in 2008. The median age at presentation was 46 years and median tumor size was 18 mm. Male/female ratio was 1/2.9. By dichotomizing the material in a time period before and after the 30th of June 2001, no significant change in the proportion of diagnosed tumors smaller than 1 or 2 cm was found, and 42.8% of the rise in incidence was explained by tumors larger than 2 cm. No significant change in diagnostic use of ultrasound or fine needle aspiration was found, and a significant change toward more extensive thyroid surgery could not be confirmed. CONCLUSION This study shows a significant rise in incidence of papillary thyroid carcinoma in Denmark from 1996 to 2008, which is not explained by increased use of preoperative diagnostic modalities. Other reasons need to be considered.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2007

Phase ii analysis of paclitaxel and capecitabine in the treatment of recurrent or disseminated squamous cell carcinoma of the head and neck region

Jens Bentzen; Hanne Sand Hansen

The aim of this phase II study was to evaluate the antitumor activity and toxicity of a non‐platin–containing regimen with paclitaxel and capecitabine.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2009

Squamous cell carcinoma of the nasal vestibule 1993-2002: a nationwide retrospective study from DAHANCA

Andreas Agger; Christian von Buchwald; Anders Rørbæk Madsen; Jesper Yde; Iana Lesnikova; Charlotte Birk Christensen; Søren Foghsgaard; Thomas Broe Christensen; Hanne Sand Hansen; Susanne Larsen; Jens Bentzen; Elo Andersen; Lisbeth Juhler Andersen; Cai Grau

A retrospective nationwide study of cancer of the nasal vestibule was conducted to evaluate classification systems and prognostic factors for treatment outcome.


Acta Oncologica | 2006

The Danish national guidelines for treatment of oral squamous cell carcinoma

Anders Bilde; Christian von Buchwald; Jørgen Johansen; Lars Bastholt; Jens Ahm Sørensen; Peter Marker; Annelise Krogdahl; Hanne Sand Hansen; Lena Specht; Jørgen Kirkegaard; Elo Andersen; Jens Bentzen; Christian Hjort-Sørensen; Lisbeth Juhler Andersen; Bengt Agathon Nielsen; Troels Bundgaard; Marie Overgaard; Cai Grau

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.


Thyroid | 2015

Papillary thyroid carcinoma in Denmark, 1996-2008

Stefano Christian Londero; Annelise Krogdahl; Lars Bastholt; Jens Overgaard; Henrik Baymler Pedersen; Christoffer Holst Hahn; Jens Bentzen; Sten Schytte; Peer Christiansen; Oke Gerke; Christian Godballe; Lisbeth Juhler Andersen; Rune Vincents Fisker; Giedrius Lelkaitis; Mariana Kristensen

BACKGROUND Regional as well as national series show an increasing incidence of thyroid cancer largely small size papillary thyroid carcinoma (PTC). Prognostic scoring systems have been developed, but these do not take into account the rapidly changing case mix, and adjustments may be required. The purposes of this study were to evaluate treatment outcomes and to analyze the value of older prognostic scoring systems tested on a relatively new, unselected national cohort of PTC patients. METHODS This was a national prospective cohort study conducted in Denmark, which has a population of 5.5 million. RESULTS A total of 1350 patients were diagnosed with PTC during 1996-2008, and the median follow-up time was 7.9 years. The 10-year recurrence-free survival rate was 90.2%, and the 10-year crude and cause-specific survival (CSS) rates were 83.7% and 93.8% respectively. By multivariate Cox regression, it was possible to confirm age, metastases (distant and nodal), extrathyroidal extension, and tumor size as predictors of mortality, whereas only nodal metastases, extrathyroidal extension, and tumor size were predictors of recurrence. In analyses of older prognostic scoring systems, a significant correlation between the risk group ranks was found for survival as well as recurrence. The c-index for CSS was highest for MACIS (0.92) and lowest for AMES (0.80). In the TNM, MACIS, and EORTC systems, most patients were classified as stage 1, and for these patients, the 10-year CSS rate was approximately 99.5%, confirming the generally excellent survival. CONCLUSION This national study provides further evidence that a favorable prognosis is to be expected for patients diagnosed with PTC. Also, it was possible to confirm age, metastases, extrathyroidal extension, and tumor size as predictors of mortality, whereas only nodal metastases, extrathyroidal extension, and tumor size were predictors of recurrence. All the scoring systems evaluated were able to produce a highly significant risk group stratification, showing that in spite of the changes in the case mix of PTC, these systems are still applicable, and in fact contain valuable prognostic information useable for treatment planning.


Laryngoscope | 1991

Nasopharyngeal carcinoma treated at the finsen institute, Copenhagen 1965-1985: Survival and some prognostic factors

Jens Bentzen; Hans H. Ockelmann; Jens Olsen; Hanne Sand Hansen

Clinical data from 218 patients consecutively treated for nasopharyngeal carcinoma at the Finsen Institute in Copenhagen during the period 1965 through 1985 have been analyzed for factors of prognostic importance. Of the 218 patients, 47 were Greenland Inuit eskimos and 169 were white Danish. The 5‐year crude survival for the entire group of patients was 30%.

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Lars Bastholt

Odense University Hospital

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Hanne Sand Hansen

Copenhagen University Hospital

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Christoffer Holst Hahn

Copenhagen University Hospital

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Annelise Krogdahl

Odense University Hospital

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Jørgen Johansen

Aarhus University Hospital

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