Circulating miRNAs as biomarkers for oral squamous cell carcinoma recurrence in operated patients.

MicroRNAs (miRNAs) are small regulatory non-coding RNAs for which altered expression in cancers can serve as potential biomarkers for diseases. We here investigated whether circulating miRNAs can serve as biomarkers for predicting post-operational recurrence of oral squamous cell carcinoma (OSCC) in patients. Plasma samples from 8 Danish OSCC patients were collected before, and one year after surgical operation, as well as from 3 Danish healthy controls and subjected to miRNA profiling by next generation sequencing. Disease recurrence did not occur in the 8 patients when the post-operative plasma samples were collected. Based on the sequencing data, three up-regulated miRNAs (miR-148a-3p, miR-26a-5p and miR-21-5p) and three down-regulated miRNAs (miR-375, miR-92b-3p and miR-486-5p) in the OSCC samples compared to healthy controls were selected for qRT-PCR validation in a Chinese cohort of 20 plasma samples collected before, and 9-12 months after surgical operation, and 18 healthy controls. Disease recurrence had occurred in 8 out of the 20 Chinese patients at the time their post-operative plasma samples were collected. The results of qRT-PCR showed that down-regulation of miR-486-5p, miR-375 and miR-92b-3p were highly associated with OSCC recurrence. This study indicates that the plasma miRNA profile is altered in OSCC during its progression and can be used to monitor the likelihood of OSCC recurrence in patients after surgery.

Gene-expression Classifier in Papillary Thyroid Carcinoma: Validation and Application of a Classifier for Prognostication.

BACKGROUND: No reliable biomarker for metastatic potential in the risk stratification of papillary thyroid carcinoma exists. We aimed to develop a gene-expression classifier for metastatic potential. MATERIALS AND METHODS: Genome-wide expression analyses were used. Development cohort: freshly frozen tissue from 38 patients was collected between the years 1986 and 2009. Validation cohort: formalin-fixed paraffin-embedded tissues were collected from 183 consecutively treated patients. RESULTS: A 17-gene classifier was identified based on the expression values in patients with and without metastasis in the development cohort. The 17-gene classifier for regional/distant metastasis identified was tested against the clinical status in the validation cohort. Sensitivity for detection of metastases was 51.5% and specificity 61.6%. Log-rank testing failed to identify any significance (p=0.32) regarding the classifier's usefulness as a prognostic marker for recurrence. CONCLUSION: A 17-gene classifier for metastatic potential was developed, and the results showed a clear biological difference between groups. However, through validation, no prognostic significance of this classifier was shown.

Sentinel European Node Trial (SENT): 3-year results of sentinel node biopsy in oral cancer.

PURPOSE: Optimum management of the N0 neck is unresolved in oral cancer. Sentinel node biopsy (SNB) can reliably detect microscopic lymph node metastasis. The object of this study was to establish whether the technique was both reliable in staging the N0 neck and a safe oncological procedure in patients with early-stage oral squamous cell carcinoma. METHODS: An European Organisation for Research and Treatment of Cancer-approved prospective, observational study commenced in 2005. Fourteen European centres recruited 415 patients with radiologically staged T1-T2N0 squamous cell carcinoma. SNB was undertaken with an average of 3.2 nodes removed per patient. Patients were excluded if the sentinel node (SN) could not be identified. A positive SN led to a neck dissection within 3 weeks. Analysis was performed at 3-year follow-up. RESULTS: An SN was found in 99.5% of cases. Positive SNs were found in 23% (94 in 415). A false-negative result occurred in 14% (15 in 109) of patients, of whom eight were subsequently rescued by salvage therapy. Recurrence after a positive SNB and subsequent neck dissection occurred in 22 patients, of which 16 (73%) were in the neck and just six patients were rescued. Only minor complications (3%) were reported following SNB. Disease-specific survival was 94%. The sensitivity of SNB was 86% and the negative predictive value 95%. CONCLUSION: These data show that SNB is a reliable and safe oncological technique for staging the clinically N0 neck in patients with T1 and T2 oral cancer. EORTC Protocol 24021: Sentinel Node Biopsy in the Management of Oral and Oropharyngeal Squamous Cell Carcinoma.

Salivary adenoid cystic carcinoma in Denmark 1990-2005: Outcome and independent prognostic factors including the benefit of radiotherapy. Results of the Danish Head and Neck Cancer Group (DAHANCA).

AIM: To describe outcome and prognostic factors, including the effect of radiotherapy, in a consecutive national series of salivary gland adenoid cystic carcinomas. METHODS: From the national Danish salivary gland carcinoma database in the structure of DAHANCA, 201 patients diagnosed with adenoid cystic carcinoma, and treated with a curative intent, were identified in the period between 1990 and 2005. Variables necessary for statistical analyses were extracted from the database. RESULTS: The 10-year crude survival and disease specific survival rates were 58% and 75%, respectively. The 10-year locoregional control rate was 70%, and 36% of patients experienced a recurrence during follow-up (median 7.5 years); 18% developed distant metastases (most commonly to the lungs). In multivariate analysis, stage and margin status were both important factors with regards to survival and locoregional control. Radiotherapy did not improve survival, but it did improve the locoregional control rate. CONCLUSIONS: The treatment of choice is surgery with as wide margins as possible including elective, selective neck dissection. Adjuvant radiotherapy should be considered in patients with incomplete tumor resection, high disease stages, and tumors with a solid growth pattern.

Papillary thyroid carcinoma in Denmark, 1996-2008: outcome and evaluation of established prognostic scoring systems in a prospective national cohort.

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.

Completeness and validity in a national clinical thyroid cancer database: DATHYRCA.

BACKGROUND: Although a prospective national clinical thyroid cancer database (DATHYRCA) has been active in Denmark since January 1, 1996, no assessment of data quality has been performed. The purpose of the study was to evaluate completeness and data validity in the Danish national clinical thyroid cancer database: DATHYRCA. STUDY DESIGN AND SETTING: National prospective cohort. Denmark; population 5.5 million. Completeness of case ascertainment was estimated by the independent case ascertainment method using three governmental registries as a reference. The reabstracted record method was used to appraise the validity. For validity assessment 100 cases were randomly selected from the DATHYRCA database; medical records were used as a reference. RESULT: The database held 1934 cases of thyroid carcinoma and completeness of case ascertainment was estimated to 90.9%. Completeness of registration was around or above 90% in most instances. Perfect agreement on the diagnosis of thyroid carcinoma was found, both inter- and intra-observer, and κ values of selected variables showed overall good to excellent agreement. CONCLUSION: In a setup with public health insurance, personal identity numbers and extended governmental databases, it is possible to establish national clinical cancer databases with a satisfactory completeness and validity. The DATHYRCA database is considered reliable in terms of describing thyroid carcinoma at a national level.

Impact of molecular screening for point mutations and rearrangements in routine air-dried fine-needle aspiration samples of thyroid nodules.

BACKGROUND: The diagnostic limitations of thyroid fine-needle aspiration (FNA), such as the indeterminate category, can be partially overcome by molecular analyses. However, until now, rearrangements have only been detected in fresh FNA material and the number of follicular thyroid carcinomas (FTCs) was rather low in previous studies. We aimed at investigating the impact of point mutations and rearrangement detection in a set of routine air-dried FNA smears with a higher percentage of FTCs. METHODS: RNA and DNA was extracted from 310 FNAs (164 indeterminate, 57 malignant, 89 benign) and corresponding formalin-fixed paraffin-embedded tissue (156 follicular adenomas [FAs], 32 FTCs, 44 papillary thyroid carcinomas [PTCs], 9 follicular variant PTCs, and 69 goiters). PAX8/PPARG and RET/PTC rearrangements were detected by qPCR, BRAF and RAS mutations by high-resolution melting PCR and by pyrosequencing. RESULTS: Forty-seven mutations were detected in the FNAs: 22 BRAF, 13 NRAS, and 3 HRAS mutations, 8 PAX8/PPARG, and one RET/PTC-rearrangement. While the presence of a BRAF and RET/PTC mutation was associated with cancer in 100% of samples each, the presence of a RAS and PAX8/PPARG mutation was associated with cancer in only 12% and 50% of samples, respectively. In the indeterminate group 4 of 25 carcinomas were identified by molecular FNA screening, which increased the sensitivity from 67% (cytology alone) to 75% (cytology plus molecular screening). CONCLUSION: Molecular screening for point mutations and rearrangements is feasible in air-dried FNAs. Although the impact of detecting point mutations and rearrangements in FNAs has most likely been overestimated in previous studies, molecular FNA analyses improve presurgical diagnostics. The detection of BRAF mutations in FNA may improve the choice of surgery and postsurgical treatment. Further data are necessary to elucidate the true impact of detecting RAS and PAX8/PPARG mutations in FNAs. The inclusion of additional rare somatic mutations and miRNA markers might further improve the impact of molecular FNA diagnostics.

Papillary thyroid microcarcinoma in Denmark 1996-2008: a national study of epidemiology and clinical significance.

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.

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

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.

Detection of PAX8/PPARG and RET/PTC rearrangements is feasible in routine air-dried fine needle aspiration smears.

BACKGROUND: The diagnostic limitations of fine needle aspiration (FNA), like the indeterminate category, can be partially overcome by molecular analysis. As PAX8/PPARG and RET/PTC rearrangements have been detected in follicular thyroid carcinomas (FTCs) and papillary thyroid carcinomas (PTCs), their detection in FNA smears could improve the FNA diagnosis. To date, these rearrangements have never been analyzed in routine air-dried FNA smears, but only in frozen tissue, formalin-fixed paraffin-embedded (FFPE) tissue, and in fresh FNA material. Fixed routine air-dried FNA samples have hitherto been judged as generally not suitable for testing these rearrangements in a clinical setting. Therefore, the objective of the present study was to investigate the feasibility of extracting RNA from routine air-dried FNA smears for the detection of these rearrangements with real-time polymerase chain reaction (RT-PCR). METHODS: A new method for RNA extraction from routine air-dried FNA smears was established, which allowed analysis for the presence of four variants of PAX8/PPARG and RET/PTC 1 and RET/PTC 3, which were analyzed in 106 routine FNA smears and the corresponding surgically obtained FFPE tissues using real-time quantitative PCR (RT-qPCR). To assess RNA quality, an intron-spanning PAX8 cDNA was amplified. RESULTS: Acceptable RNA quality was obtained from 95% of the FNA samples and 92% of the FFPE samples. PAX8/PPARG was detected in 4 of 96 FFPEs and in 6 of 96 FNAs. PAX8/PPARG was present in 4 of 10 FTCs and in 3 of 42 follicular adenomas (FAs). Similarly, RET/PTC was found in 3 of 96 FFPEs and in 4 of 96 FNAs. Two of 21 PTC samples and 3 of 42 FA samples carried this rearrangement. CONCLUSION: These data are the first to show the feasibility of extracting RNA from routine air-dried FNA smears for the detection of PAX8/PPARG and RET/PTC rearrangements with RT-qPCR. These promising methodological advances, if confirmed in larger series of FNA and FFPE samples, may lead to the introduction of molecular analysis of routine air-dried FNA smears in everyday practice.

Aggressive elimination of precancerous lesions of the vocal cords to avoid risk of cancer.

INTRODUCTION: Several studies show that early histological classification and excision of precancerous lesions of the vocal cords reduces the risk of cancer development. National Danish guidelines have not been established. The purpose of this study was to describe a Danish series of patients with precancerous lesions of the vocal cords and to estimate the risk of malignant transformation. MATERIAL AND METHODS: This was a retrospective cohort study, including a total of 101 patients with histologically verified precancerous lesions of the vocal cords who were treated from 1997 to 2007 at Odense University Hospital (OUH). RESULTS: Among the 101 patients, 18 (18%) were diagnosed with mild dysplasia, 16 (16%) with moderate dysplasia, 35 (35%) with severe dysplasia and 32 (32%) with carcinoma in situ (CIS) at the initial examination at OUH. Fifteen patients (15%), all males, developed invasive cancer. Among these, one patient was initially diagnosed with mild dysplasia, one with moderate dysplasia, seven with severe dysplasia and six with CIS. In 11 of the 15 patients (73%), cancer occurred within one year from the time of diagnosis of the precancerous lesion, whereas four cancers occurred years later. CONCLUSION: The malignant transformation rate is comparable with other recent series. A strategy with elimination of all visible pathology is preferable. FUNDING: not relevant. TRIAL REGISTRATION: not relevant.

Prognostic significance of Ki-67 in salivary gland carcinomas.

BACKGROUND: Salivary gland carcinomas are a heterogeneous group of tumors with varying malignant potential. In this study, we evaluated the proliferative marker Ki-67 in salivary gland carcinomas and related the Ki-67 index to clinical data. METHODS: A total of 176 salivary gland carcinomas of 13 different subtypes were stained immunohistochemically for Ki-67. The number of Ki-67 positive cells was counted and the Ki-67 index was calculated as the percentage of positive tumor cells. RESULTS: The Ki-67 median value was 26 (range 1-99). The median follow-up time was 6.9 years (range 0-19 years). The 5- and 10-year crude survival was 70% and 59%, respectively. In univariate analysis, Ki-67 index, stage, vascular invasion and tumor grade were significantly related to crude survival, but in multivariate analysis only Ki-67 index, age, and stage were independent prognostic factors. CONCLUSION: We showed that irrespective of subtyping, grading or morphological appearance of tumor, the Ki-67 index is an important and independent prognosticator. Clinical and histo-pathological data must be considered, when planning the treatment of the individual patient. We have shown that besides stage and age of the patient, Ki-67 is a strong, independent prognostic factor.

[Bilateral sarcoidosis of parotid glands]. / Bilateral sarkoidose i glandula parotis.

We describe an unusual case of sarcoidosis in which the patient presented with a bilateral swelling of the parotid salivary glands and no other manifestation of the disease. Sarcoidosis is a multisystem granulomatous disorder of unknown cause in which there may be multiple exocrine involvement, including the salivary glands. This case emphasises the importance of including sarcoidosis in the differential diagnosis of bilateral parotid swelling.

Salivary gland carcinomas of the larynx: a national study in Denmark.

OBJECTIVE: Salivary gland carcinomas of the larynx are rare. The purpose of this study is to present a national series of laryngeal salivary gland carcinoma patients and to bring a review of recent literature. METHODS: By merging The Danish Cancer Registry, The National Pathology Registry and The National Patient Registry all registered patients with laryngeal salivary carcinomas diagnosed from 1990 to 2007 were identified. The histological slides were reviewed and data concerning age, sex, symptoms, topography, histology, treatment and outcome were registered. Based on a supplemented PubMed search a review of literature from 1991 to 2010 was performed. RESULTS: Six Danish patients with a malignant salivary gland tumor in the larynx were identified resulting in an incidence of 0.001/100,000 inhabitants/year. Four had adenoid cystic carcinoma and two a mucoepidermoid carcinoma. All patients were male. The patients were treated with surgery and/or radiotherapy. Three patients had recurrent disease. One died of the primary disease and one died of other causes. Four are alive with no evidence of disease. Merging of actual study group with patients from recent literature resulted in 83 cases. The male vs. female ratio was 2:1, the most common location was the supraglottic region (52%) and the most predominant histological subtypes were adenoid cystic carcinoma (46%), mucoepidermoid carcinoma (35%) and adenocarcinoma NOS (12%). CONCLUSION: Laryngeal salivary gland carcinoma is a rare disease with a male predominance and most often localized in the supraglottic region. Data concerning treatment and outcome are scarce, but primary surgery with utmost focus on free surgical margins is the treatment of choice. Recurrences are observed later than ten years after primary treatment and a long follow up time is advocated.

Salivary gland carcinoma in Denmark 1990-2005: outcome and prognostic factors. Results of the Danish Head and Neck Cancer Group (DAHANCA).

To describe outcome and prognostic factors in a national Danish series of patients treated for salivary gland carcinoma. From three Danish nation-wide registries and supplementary patient records, 871 patients diagnosed with primary major or minor salivary gland carcinoma in the period from 1990 to 2005 were identified. A total of 796 (91%) histological specimens were revised according to the WHO 2005 classification. The median follow-up time was 78 months. Three hundred and thirty-four patients (38%) experienced recurrence. Crude survival, disease-specific survival and recurrence-free survival after 5 and 10 years were 66%, 76%, 64% and 51%, 69%, 58%, respectively. In multivariate analysis age, latency, stage, microscopic margins, vascular invasion and histological grade were all independent prognostic factors with regards to crude and disease-specific survival. Stage, microscopic margins, vascular invasion and histological grade were independent prognostic factors for recurrence-free survival. Age over 61 years, latency under 8 months, stage 3+4 disease, involved or close microscopic margins, vascular invasion and high histological grade are all independent prognostic factors with a negative impact on survival in salivary gland carcinoma patients. This knowledge can be helpful in guiding clinicians in daily work and choice of treatment across the large variety of salivary gland carcinoma subtypes.

Down-regulation of microRNAs controlling tumourigenic factors in follicular thyroid carcinoma.

The molecular determinants of thyroid follicular nodules are incompletely understood and assessment of malignancy is a diagnostic challenge. Since microRNA (miRNA) analyses could provide new leads to malignant progression, we characterised the global miRNA expression in follicular adenoma (FA) and follicular carcinoma (FC). Comparison of carcinoma and adenoma with normal thyroid revealed 150 and 107 differentially expressed miRNAs respectively. Most miRNAs were down-regulated and especially miR-199b-5p and miR-144 which were essentially lost in the carcinomas. Integration of the changed miRNAs with differentially expressed mRNAs demonstrated an enrichment of seed sites among up-regulated transcripts encoding proteins implicated in thyroid tumourigenesis. This was substantiated by the demonstration that pre-miR-199b reduced proliferation when added to cultured follicular thyroid carcinoma cells. The down-regulated miRNAs in FC exhibited a substantial similarity with down-regulated miRNAs in anaplastic carcinoma (AC) and by gene set enrichment analysis, we observed a significant identity between target mRNAs in FC and transcripts up-regulated in AC. To examine the diagnostic potential of miRNA expression pattern in distinguishing malignant from benign nodules we employed a supervised learning algorithm and leave-one-out-cross-validation. By this procedure, FA and FC were identified with a negative predicted value of 83% (data generated by microarray platform) and of 92% (data generated by qRT-PCR platform). We conclude that follicular neoplasia is associated with major changes in miRNA expression that may promote malignant transformation by increasing the expression of transcripts encoding tumourigenic factors. Moreover, miRNA profiling may facilitate the diagnosis of carcinoma vs adenoma.

MicroRNA alterations and associated aberrant DNA methylation patterns across multiple sample types in oral squamous cell carcinoma.

BACKGROUND: MicroRNA (miRNA) expression is broadly altered in cancer, but few studies have investigated miRNA deregulation in oral squamous cell carcinoma (OSCC). Epigenetic mechanisms are involved in the regulation of >30 miRNA genes in a range of tissues, and we aimed to investigate this further in OSCC. METHODS: TaqMan® qRT-PCR arrays and individual assays were used to profile miRNA expression in a panel of 25 tumors with matched adjacent tissues from patients with OSCC, and 8 control paired oral stroma and epithelium from healthy volunteers. Associated DNA methylation changes of candidate epigenetically deregulated miRNA genes were measured in the same samples using the MassArray® mass spectrometry platform. MiRNA expression and DNA methylation changes were also investigated in FACS sorted CD44(high) oral cancer stem cells from primary tumor samples (CSCs), and in oral rinse and saliva from 15 OSCC patients and 7 healthy volunteers. RESULTS: MiRNA expression patterns were consistent in healthy oral epithelium and stroma, but broadly altered in both tumor and adjacent tissue from OSCC patients. MiR-375 is repressed and miR-127 activated in OSCC, and we confirm previous reports of miR-137 hypermethylation in oral cancer. The miR-200 s/miR-205 were epigenetically activated in tumors vs normal tissues, but repressed in the absence of DNA hypermethylation specifically in CD44(high) oral CSCs. Aberrant miR-375 and miR-200a expression and miR-200c-141 methylation could be detected in and distinguish OSCC patient oral rinse and saliva from healthy volunteers, suggesting a potential clinical application for OSCC specific miRNA signatures in oral fluids. CONCLUSIONS: MiRNA expression and DNA methylation changes are a common event in OSCC, and we suggest miR-375, miR-127, miR-137, the miR-200 family and miR-205 as promising candidates for future investigations. Although overall activated in OSCC, miR-200/miR-205 suppression in oral CSCs indicate that cell specific silencing of these miRNAs may drive tumor expansion and progression.

Salivary gland carcinoma in Denmark 1990-2005: a national study of incidence, site and histology. Results of the Danish Head and Neck Cancer Group (DAHANCA).

To describe the incidence, site and histology (WHO 2005) of salivary gland carcinomas in Denmark. Nine hundred and eighty-three patients diagnosed from 1990 to 2005 were identified from three nation-wide registries. The associated clinical data were retrospectively retrieved from patient medical records. Histological revision was performed in 886 cases (90%). Based on histological revision, 31 patients (3%) were excluded from the study leaving 952 for epidemiological analysis. The mean crude incidence in Denmark was 1.1/100,000/year. The male vs. female ratio was 0.97 and the median age was 62 years. The parotid gland was the most common site (52.5%) followed by the minor salivary glands of the oral cavity (26.3%). The most frequent histological subtypes were adenoid cystic carcinoma (25.2%), mucoepidermoid carcinoma (16.9%), adenocarcinoma NOS (12.2%) and acinic cell carcinoma (10.2%). The revision process changed the histological diagnosis in 121 out of 886 cases (14%). The incidence of salivary gland carcinoma in Denmark is higher than previously reported. More than half of salivary gland carcinomas are located in the parotid gland with adenoid cystic carcinoma being the most frequent subtype. Histological classification of salivary gland carcinomas is difficult and evaluation by dedicated pathology specialists might be essential for optimal diagnosis and treatment.

The influence of HPV-associated p16-expression on accelerated fractionated radiotherapy in head and neck cancer: evaluation of the randomised DAHANCA 6&7 trial.

BACKGROUND AND PURPOSE: Tumour HPV-positivity is a favourable prognostic factor in the radiotherapy of HNSCC, but the optimal radiotherapy regimen for HPV-positive HNSCC is not yet defined. Reducing overall treatment time is known to improve outcome in the radiotherapy of HNSCC as was also demonstrated in the randomised DAHANCA 6&7 trial. We aimed to assess the influence of tumour HPV-status, expressed by p16, on the response to accelerated fractionated radiotherapy in HNSCC through evaluation of the DAHANCA 6&7 trial. MATERIALS AND METHODS: Immunohistochemical detection of HPV-associated p16-expression was performed on FFPE-pre-treatment tumour-tissues from 794 patients enrolled in the DAHANCA 6&7 trial. The influence of tumour p16-status on loco-regional tumour control and survival as a function of fractionation schedule (5Fx/week vs 6Fx/week) was evaluated 5years after the completion of radiotherapy. RESULTS: The significant and independent prognostic value of tumour p16-positivity in HNSCC radiotherapy was confirmed, with adjusted hazard ratios (HR) of 0.58 [0.43-0.78], 0.47 [0.33-0.67] and 0.54 [0.42-0.68] for loco-regional control, disease-specific and overall survival, respectively. Accelerated radiotherapy significantly improved loco-regional tumour control compared to conventional radiotherapy, adjusted HR: 0.73 [0.59-0.92] and the benefit of the 6Fx/week regimen was observed both in p16-positive (HR: 0.56 [0.33-0.96]) as well as in p16-negative tumours (HR: 0.77 [0.60-0.99]). Disease-specific survival was also significantly improved with accelerated radiotherapy in the group of p16-positive tumours (adjusted HR: 0.43 [0.22-0.82]). CONCLUSION: Accelerated radiotherapy significantly improves outcome in HNSCC compared to conventional fractionation. The observed benefit is independent of tumour p16-status and the use of a moderately accelerated radiotherapy regimen seems advantageous also for HPV/p16-positive HNSCC.