High-risk human papillomaviruses (HPVs) have been proposed to be associated with a subset of head and neck cancers (HNSCCs). However, clear biological evidence linking HPVmediated oncogenesis to the development of HNSCC is hardly available. An important biological mechanism underlying HPV-mediated carcinogenesis is the inactivation of p53 by the HPV E6 oncoprotein. In the present study we investigated this biological relationship between HPV and HNSCC. In total 84 HNSCC tumors were analyzed for the presence of high-risk HPV nucleic acids by DNA polymerase chain reaction-enzyme immunoassay (PCR-EIA) and E6 reverse transcriptase (RT)-PCR as well as for the presence of mutations in the p53 gene. We found 20/84 HPV16 DNA-positive cases with one or more DNA assays, 10 of which were consistently positive with all assays. Only 9/20 cases showed E6 mRNA expression, indicative for viral activity. Only these nine E6 mRNA-positive cases all lacked a p53 mutation, whereas both the other HPV DNA-positive and HPV-DNA negative tumors showed p53 mutations in 36% and 63% of the cases, respectively. Moreover, only in lymph node metastases of HPV E6 mRNA-positive tumors both viral DNA and E6 mRNA were present. Our study provides strong biological evidence for a plausible etiological role of high-risk HPV in a subgroup of HNSCC. Analysis of E6 mRNA expression by RT-PCR or alternatively, semiquantitative analyses of the viral load, seem more reliable assays to assess HPV involvement in HNSCC than the very sensitive DNA PCR analyses used routinely. © 2001 Wiley-Liss, Inc. Key words: papillomavirus; head and neck cancer; squamous cell carcinoma; p53 mutations; E6 oncoproteinMucosotropic high-risk human papillomaviruses (HPVs), known to cause cervical and other anogenital cancers, have been proposed to play a role in the etiology of head and neck squamous cell carcinomas (HNSCCs). 1 The presence of high-risk HPV DNA in a subgroup of HNSCCs has supported this hypothesis. [2][3][4][5] Molecular studies have provided important data on the role and oncogenic mechanism of high-risk HPV in carcinogenesis. 6 -8 By expression of the viral oncoproteins E6 and E7, the virus dysregulates crucial cellular mechanisms such as the cell cycle and the apoptotic pathway. The E6 oncoprotein specifically inactivates wild-type p53, and the E7 oncoprotein inactivates Rb. In this way the high-risk HPV E6-mediated degradation of the p53 protein should be considered an alternative pathway for "classical" mutation to knock-out the p53 regulated pathways; it provides the biological basis to expect that tumors originating from HPV infection will show wild-type p53. Indeed, this general biological mechanism is supported by the finding that p53 mutations hardly occur in cervical carcinomas. 9,10 However, in most studies on head and neck cancer, HPV DNA presence and p53 mutations were overlapping, 2,11,12 an observation that gave rise to a long debate as to whether HPV is causally related to the development of a subset of these tumors.On the other hand, the inconsi...
Salivary duct carcinoma (SDC) is a subtype of salivary gland cancer with a dismal prognosis and a need for better prognostication and novel treatments. The aim of this national cohort study was to investigate clinical outcome, prognostic factors, androgen receptor (AR) and human epidermal growth factor receptor 2 (HER2) expression. SDC patients diagnosed between 1990 and 2014 were identified by the Nationwide Network and Registry of Histo‐ and Cytopathology in the Netherlands (PALGA). Subsequently, medical records were evaluated and pathological diagnoses reviewed. Data were analyzed for overall survival (OS), disease‐free survival (DFS), distant metastasis‐free survival (DMFS) and prognostic factors. AR was evaluated by immunohistochemistry (IHC), HER2 by IHC and fluorescent in‐situ hybridization. A total of 177 patients were included. The median age was 65 years, 75% were male. At diagnosis, 68% presented with lymph node metastases and 6% with distant metastases. Median OS, DFS and DMFS were 51, 23 and 26 months, respectively. In patients presenting without distant metastases, the absolute number of positive lymph nodes was associated with poor OS and DMFS in a multivariable analysis. AR and HER2 were positive in 161/168 (96%) and 44/153 (29%) tumors, respectively, and were not prognostic factors. SDC has a dismal prognosis with primary lymph node involvement in the majority of patients. The absolute number of lymph node metastases was found to be the only prognostic factor for DMFS and OS. AR expression and—to a lesser extent—HER2 expression hold promise for systemic treatment in the metastatic and eventually adjuvant setting.
In total, 10-30% of patients with head and neck squamous cell carcinoma (HNSCC) develop local recurrences despite seemingly adequate tumour resection. This may result from minimal residual cancer (MRC): small numbers of tumour cells left behind in the surgical margins, undetectable by routine histopathology. In recent studies, p53 mutations have been considered as selective and sensitive DNA markers of cancer cells. There are two potential problems in using mutated-p53 DNA as a marker. Firstly, p53 mutations occur early in progression and might therefore detect unresected precursor lesions besides tumour cells. Secondly, DNA is a very stable biomolecule that might lead to false-positive results. These two potential problems have been evaluated in this study. Fifty patients with a radical tumour resection were included, of whom 30 showed a p53 mutation in the primary tumour. Histopathologically tumour-free surgical margins were quantitatively analysed for mutated p53 by molecular diagnosis (plaque assay) and subsequent (immuno)histopathology. p53 mutated DNA was detected in the surgical margins of 19/30 patients. Immunohistochemistry confirmed the presence of small tumour foci in 2/19 mutated p53-positive cases. In 7/19 cases, the tumour-specific p53 mutation was found in unresected dysplastic mucosal precursor lesions. Moreover, in a number of cases small p53-immunostained patches were detected, but the mutations found were never tumour-related. By screening contralateral exfoliated cells and plaque assays on RNA it was shown that detection of mutated-p53 DNA is prone to false-positive results. In conclusion, using p53 mutations as a marker, both MRC and unresected mutated p53-positive mucosal precursor lesions are detected within surgical margins. Molecular assessment of surgical margins using p53 mutations enables the selection of HNSCC patients at high risk for tumour recurrence, but tumour RNA seems at present to be a more specific biomolecule for analysis than tumour DNA.
This pooled analysis suggests that there is a clear advantage in using vascularized tissue from outside the radiation field in the laryngectomy defect. While some studies show a clear reduction in PCF rates, others suggest that the fistulae that occur are smaller and rarely need repair.
PurposeThis study was designed to examine the feasibility of combining lymphoscintigraphy and intraoperative sentinel node identification in patients with head and neck melanoma by using a hybrid protein colloid that is both radioactive and fluorescent.MethodsEleven patients scheduled for sentinel node biopsy in the head and neck region were studied. Approximately 5 h before surgery, the hybrid nanocolloid labeled with indocyanine green (ICG) and technetium-99m (99mTc) was injected intradermally in four deposits around the scar of the primary melanoma excision. Subsequent lymphoscintigraphy and single photon emission computed tomography with computed tomography (SPECT/CT) were performed to identify the sentinel nodes preoperatively. In the operating room, patent blue dye was injected in 7 of the 11 patients. Intraoperatively, sentinel nodes were acoustically localized with a gamma ray detection probe and visualized by using patent blue dye and/or fluorescence-based tracing with a dedicated near-infrared light camera. A portable gamma camera was used before and after sentinel node excision to confirm excision of all sentinel nodes.ResultsA total of 27 sentinel nodes were preoperatively identified on the lymphoscintigraphy and SPECT/CT images. All sentinel nodes could be localized intraoperatively. In the seven patients in whom blue dye was used, 43% of the sentinel nodes stained blue, whereas all were fluorescent. The portable gamma camera identified additional sentinel nodes in two patients. Ex vivo, all radioactive lymph nodes were fluorescent and vice versa, indicating the stability of the hybrid tracer.ConclusionsICG–99mTc-nanocolloid allows for preoperative sentinel node visualization and concomitant intraoperative radio- and fluorescence guidance to the same sentinel nodes in head and neck melanoma patients.Electronic supplementary materialThe online version of this article (doi:10.1245/s10434-011-2180-7) contains supplementary material, which is available to authorized users.
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