Annelise Krogdahl

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.

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 CD44high 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 CD44high 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.

Genetic and epigenetic alterations of the blood group ABO gene in oral squamous cell carcinoma

Loss of histo‐blood group A and B antigen expression is a frequent event in oral carcinomas and is associated with decreased activity of glycosyltransferases encoded by the ABO gene. We examined 30 oral squamous cell carcinomas for expression of A and B antigens and glycosyltransferases. We also examined DNA from these tumors for loss of heterozygosity (LOH) at markers surrounding the ABO locus at chromosome 9q34, for loss of specific ABO alleles, and for hypermethylation of the ABO promoters. Loss of A or B antigen expression was found in 21 of 25 tumors (84%) and was a consistent feature of tumors lacking expression of A/B glycosyltransferases. LOH at 9q34 was found in 7 of 27 cases (26%), and one case showed microsatellite instability. Among 20 AO/BO cases, 3 showed loss of the A/B allele and 3 showed loss of the O allele. Analysis of the proximal ABO promoter by methylation‐specific PCR and melting curve analysis showed hypermethylation in 10 of 30 tumors (33.3%), which was associated with loss of A/B antigen expression. ABO promoter hypermethylation was also found in hyperplastic or dysplastic tissues adjacent to the tumors, suggesting that it is an early event in tumorigenesis. Collectively, we have identified molecular events that may account for loss of A/B antigen expression in 67% of oral squamous cell carcinomas.

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.

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.

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.

Parotid Carcinoma: Impact of Clinical Factors on Prognosis in a Histologically Revised Series

Objective To analyze clinical data and possible prognostic factors of patients with primary carcinoma of the parotid gland.

Value of fine-needle aspiration biopsy of salivary gland lesions

The aim of this study was to assess the utility of fine‐needle aspiration biopsy (FNAB) in the diagnosis and treatment planning of the lesions of the salivary gland.

Does Tumor Depth Affect Nodal Upstaging in Squamous Cell Carcinoma of the Head and Neck

Purpose: The aim of this study was to determine whether tumor depth affects upstaging of the clinically node‐negative neck, as determined by sentinel lymph node biopsy with full pathologic evaluation of harvested nodes including step‐serial sectioning (SSS) and immunohistochemistry (IHC).