Cidofovir induces an increase in levels of low-risk and high-risk HPV E6

BACKGROUND

Cidofovir is a nucleoside analogue that is used off-license to treat recurrent respiratory papillomatosis (RRP) caused by HPV6/11. However, the effect of this drug upon low-risk HPV 6/11 gene expression is unknown.

METHODS

The expression of E6 was evaluated by RT-PCR in HPV-ve C33A cervical carcinoma cells stably transfected with both low- and high-risk HPV E6 cDNA's and in SiHa (HPV16+ve) cervical carcinoma cells after treatment with 2 doses and durations of exposure to cidofovir.

RESULTS

Compared to the vector only transcript, E6 RNA levels showed an 8-fold increase in low-risk and 20-fold increase in high-risk E6-expressing cells. High-risk E6 protein levels were also detected by Western blot in cidofovir-treated C33A Type16 E6-transfected cells.

CONCLUSION

These data may indicate a potential rationale for increased risk of genetic instability and thus transformation due to drug-induced increase in the level of E6.

The impact of radiotherapy on swallowing and speech in patients who undergo total laryngectomy

OBJECTIVES

Quality of life studies have shown no detrimental effect with radiotherapy (RT) in patients who have a total laryngectomy. We wished to determine the effect of RT (initial or postoperative) specifically on the swallowing and voice function in patients treated by total laryngectomy (TL) for carcinoma of the larynx.

DESIGN

Multicenter chart review.

SETTING

Multicenter study in the Greater Manchester and Lancashire area.

PARTICIPANTS

A total of 121 postlaryngectomy patients all of whom had completed definitive treatment at least 6 months before this study. Twenty-six patients had total laryngectomy as a single modality treatment and 95 had total laryngectomy and radiotherapy.

MAIN OUTCOME MEASURES

Swallowing (solid food, soft diet or fluid/PEG) and voice development.

RESULTS

Swallowing was better in the group who had no radiotherapy (P = 0.0037). There was no difference in voice function between the two groups. We also demonstrated that females had a worse swallowing outcome (P = 0.0101), as did advanced nodal stage (P = 0.001).

CONCLUSIONS

RT adversely affects the swallowing results but not the speech results after TL when given either as initial treatment or postoperatively. This should be kept in mind in the decision-making process in the treatment of patients with carcinoma of the larynx.

Audit of clinical coding of major head and neck operations

INTRODUCTION

Within the NHS, operations are coded using the Office of Population Censuses and Surveys (OPCS) classification system. These codes, together with diagnostic codes, are used to generate Healthcare Resource Group (HRG) codes, which correlate to a payment bracket. The aim of this study was to determine whether allocated procedure codes for major head and neck operations were correct and reflective of the work undertaken. HRG codes generated were assessed to determine accuracy of remuneration.

PATIENTS AND METHODS

The coding of consecutive major head and neck operations undertaken in a tertiary referral centre over a retrospective 3-month period were assessed. Procedure codes were initially ascribed by professional hospital coders. Operations were then recoded by the surgical trainee in liaison with the head of clinical coding. The initial and revised procedure codes were compared and used to generate HRG codes, to determine whether the payment banding had altered.

RESULTS

A total of 34 cases were reviewed. The number of procedure codes generated initially by the clinical coders was 99, whereas the revised codes generated 146. Of the original codes, 47 of 99 (47.4%) were incorrect. In 19 of the 34 cases reviewed (55.9%), the HRG code remained unchanged, thus resulting in the correct payment. Six cases were never coded, equating to pound15,300 loss of payment.

CONCLUSIONS

These results highlight the inadequacy of this system to reward hospitals for the work carried out within the NHS in a fair and consistent manner. The current coding system was found to be complicated, ambiguous and inaccurate, resulting in loss of remuneration.

Scientific and clinical aspects of the use of cidofovir in recurrent respiratory papillomatosis

OBJECTIVE

Cidofovir is the most contemporary adjuvant treatment for recurrent respiratory papillomatosis (RRP) and its use is increasing. Cidofovir is potentially harmful. Otolaryngologists should understand the science of cidofovir and review the current published data on the effects of this therapy.

METHOD

Pubmed was searched using the terms cidofovir and papillomatosis. Comparisons were made between published articles.

RESULTS

Thirteen articles were identified between 1998 and 2006, representing the treatment of 142 patients. Cidofovir did result in a significant improvement of papillomatous lesions in the majority (60%) of patients despite the use of different regimes of cidofovir administration. There was no unifying protocol in use. A partial response was demonstrated in 29% of patients. 7.5% had no response however, an additional 3.5% patients were lost to follow-up. No malignant change was reported.

CONCLUSION

Cidofovir does appear to be effective in improving the outcome of patients with RRP. There are no reports of malignant transformation despite concerns raised by toxicology studies.

Clinical and biological factors affecting response to radiotherapy in patients with head and neck cancer: a review

OBJECTIVE

The main aim of this article was to review the clinical and biological factors that have been shown to influence the response of the head and neck squamous cell carcinoma (HNSCC) to primary radiotherapy and briefly discuss how some of these factors could be exploited to improve outcome.

DESIGN

Medline based search covering 1982-2006 to identify the HNSCC literature where the effect of clinical and biological factors on locoregional control and overall survival were investigated.

RESULTS

Clinical factors are routinely used in management decisions. Nevertheless, identically staged tumours receiving the same treatment may have different outcomes. Biological factors such as hypoxia, proliferation and radio-sensitivity play an important role in radiation response. However, these are not currently used in practise because tests that are clinically reliable and feasible are not available.

CONCLUSION

High-quality translational research will allow us to develop biological tests that can be used in routine clinical practise to tailor individual treatment, with the ability to improve patient outcome further by modifying the underlying tumour biology.

Effects of cidofovir on a novel cell-based test system for recurrent respiratory papillomatosis

BACKGROUND

Cidofovir has been reported to have activity against human papillomavirus (HPV) type 16, but no laboratory studies have been performed on HPV type 6, the main cause of recurrent respiratory papillomatosis (RRP).

METHODS

HPV6b E6 cDNA-based C33A (non-HPV cervical carcinoma) cell line was produced. Two different doses of cidofovir were applied to parent C33A, C33AT6E6, and C33AT16E6 (HPV 16). Growth and flow cytometry analysis were performed.

RESULTS

Polymerase chain reaction confirmed HPV6 E6 expression in C33AT6E6 cells. High-dose cidofovir was found to be toxic to all cell lines. Low-dose exposure was found to be toxic to C33AT16E6 cells at 3 days, whereas C33A and C33AT6E6 showed minimal toxicity at 6 days and earlier recovery following drug withdrawal.

CONCLUSIONS

Cidofovir showed nonspecific toxicity against all 3 cell lines tested. HPV16 E6 expressing cells were more sensitive than parent or HPV6 E6 expressing cells. Cidofovir has no selective advantage for the RRP-related HPV6 E6 expressing cell line.

Angioedema of the airway: an unusual case

We report a case of angioedema caused by angiotensin-converting enzyme inhibitor and topical lignocaine spray, administered during nasendoscopy.

Angioedema induced by angiotensin-converting enzyme inhibitors is a rare but well known entity. Allergy to topical lignocaine has been acknowledged as a rare phenomenon when used for dental surgery and for skin anaesthesia, but it has not previously been reported after topical administration prior to nasendoscopy. In the reported case, our patient was unfortunate enough to be allergic to both lisinopril and lignocaine. The result was life-threatening airway obstruction, and the continued use of lignocaine spray sustained the laryngeal oedema. We advise that patients are asked about any and every allergy – specifically, any previous problems with dental procedures – before administration of local anaesthetic spray to the upper aerodigestive tract.

Relation of a hypoxia metagene derived from head and neck cancer to prognosis of multiple cancers

Affymetrix U133plus2 GeneChips were used to profile 59 head and neck squamous cell cancers. A hypoxia metagene was obtained by analysis of genes whose in vivo expression clustered with the expression of 10 well-known hypoxia-regulated genes (e.g., CA9, GLUT1, and VEGF). To minimize random aggregation, strongly correlated up-regulated genes appearing in >50% of clusters defined a signature comprising 99 genes, of which 27% were previously known to be hypoxia associated. The median RNA expression of the 99 genes in the signature was an independent prognostic factor for recurrence-free survival in a publicly available head and neck cancer data set, outdoing the original intrinsic classifier. In a published breast cancer series, the hypoxia signature was a significant prognostic factor for overall survival independent of clinicopathologic risk factors and a trained profile. The work highlights the validity and potential of using data from analysis of in vitro stress pathways for deriving a biological metagene/gene signature in vivo.

Should FDG-PET scanning be routinely used for patients with an unknown head and neck squamous primary?

Background: Between 1 and 2 per cent of head and neck squamous cell carcinoma patients will reveal no evidence of a primary malignancy. The management of this group poses many problems, including the morbidity associated with wide field irradiation as well as the difficulty in treatment when a primary does emerge. The aim of this study was to assess the use of fluoro-deoxy-glucose positron emission tomography (FDG-PET) imaging in patients presenting with an unknown head and neck primary and to consider its routine use in such patients.

Methods: We enrolled 25 patients into our study over a four year period. They all presented with a histologically proven, metastatic, squamous cell carcinoma of the neck for which no primary could be found despite full clinical, endoscopic and radiological evaluation with computed tomography (CT) and/or magnetic resonance imaging (MRI). Additionally, all the patients underwent imaging using FDG-PET. The images were interpreted by two radiologists experienced in PET imaging.

Results: A primary was identified in nine of the 25 patients (42 per cent); however, of these patients, six had false positive results and only three patients were true positives with supportive histology. In the remaining 16 patients, no abnormality was identified on CT, MRI or PET. Of these 16 patients, two eventually displayed a primary carcinoma, the other 14 patients remaining without evidence of any primary.

Conclusion: Despite the high number of positive PET scans, the actual true positive rate was 3/9 (33 per cent); conversely, the true negative rate was 14/16 (88 per cent). We conclude from this study that there is a role for FDG-PET in the patient with an unknown head and neck primary, particularly in the context of a negative PET scan.

Hypoxia in head and neck cancer

A high level of hypoxia in solid tumours is an adverse prognostic factor for the poor outcome of cancer patients following treatment. This review describes the status of research into finding a practical method for measuring hypoxia and treating hypoxic tumours. The application of such methodology would enable the selection of head and neck cancer treatment based on an individual's tumour oxygenation status. This individualization would include the selection not only of surgery or radiotherapy, but also of novel hypoxia-modification strategies.

Synergistic effects of imatinib (STI 571) in combination with chemotherapeutic drugs in head and neck cancer

The tyrosine kinase inhibitor imatinib (STI 571; glivec) is a potent inhibitor of bcr-abl, c-kit and platelet-derived growth factor receptors. Imatinib was evaluated both alone and in combination with established chemotherapeutic agents in adenoid cystic carcinoma (ACC) primary cultures and established cell lines representing squamous cell carcinoma of the head and neck (HNSCC). Over 90% of ACC tumors are c-kit-positive, and these primary cultures proved to be of short-term usefulness in assessing chemosensitivity. Interaction was determined over a wide range of drug combinations using a statistical three-dimensional analysis model. Both ACC short-term cultures and HNSCC cell lines were demonstrated to have a response ranging from additive to synergistic when imatinib and cisplatin were combined. The interaction of imatinib on cisplatin-induced DNA cross-linking was further investigated using the comet-X assay. In contrast, significant antagonism was observed when imatinib and gemcitabine were combined. Since gemcitabine is activated by deoxycytidine kinase (dCK), the effect of imatinib on this enzyme was investigated. A dose-dependent inhibition of dCK was observed, highlighting this kinase as a possible additional secondary molecular target for imatinib. This work demonstrates a synergistic interaction between cisplatin and imatinib, which may prove to be clinically relevant in the future management of both ACC and HNSCC.

Otic drops used to clear a blocked grommet: an in vitro prospective randomized controlled study with blinded assessment

Clinicians often prescribe otic drops anecdotally to try and clear grommets blocked with blood. We carried out an in vitro double-blind randomized controlled study comparing the efficacy of sodium bicarbonate, Locorten Vioform and olive oil drops in clearing Shah grommets placed in 'artificial ears' and blocked with blood in a standardized fashion. There were 33 grommets in each group, and drops were inserted three times a day for 7 days. Olive oil drops cleared 17 of 33 (51.51%), Locorten Vioform cleared one of 33 (3%) and sodium bicarbonate cleared zero of 33 (0%) blocked grommets. Statistical comparison between pairs indicates that olive oil was significantly better than both Locorten Vioform (P < 0.001) and sodium bicarbonate drops (P < 0.001) at clearing grommets blocked with blood.

The assessment of topical nasal drug distribution

The mainstay of treatment of chronic rhinosinusitis is through the administration of topical nasal drugs. The delivery and intranasal distribution of these is therefore of potential clinical significance. Until there is progress in the nasal drug distribution assessment methodology, it will be difficult to improve topical nasal drug delivery, which is known to be suboptimal in many ways. This study reviews intranasal drug delivery assessment methods, the present knowledge and explores future directions for research.

Angiogenesis and the Expression of Vascular Endothelial Growth Factors A and C in Squamous Cell Carcinoma of the Piriform Fossa

BACKGROUND

Angiogenesis is essential for tumor growth and invasion. Vascular endothelial growth factor A (VEGF-A) is a prime mediator of tumor angiogenesis; VEGF-C, another member of the closely related VEGF family of proteins, has major effects on lymphatic endothelial cells and may be important in the process of lymphatic metastasis.

OBJECTIVES

To evaluate the expression of these cytokines in hypopharyngeal squamous cell carcinoma and to ascertain the effects of these proteins on lymphatic metastasis and vascular angiogenesis.

DESIGN

Retrospective analysis of microvessel density and the expression of VEGF-A and VEGF-C.

SETTING

An academic referral center. Subjects Thirty-four patients with stage T2 to T4 squamous cell carcinoma of the piriform fossa.

INTERVENTIONS

Expression of VEGF-A and VEGF-C was determined by immunohistochemistry on formalin-fixed, paraffin-embedded biopsy specimens. Angiogenesis was measured as microvessel density by staining endothelial cells for platelet-endothelial cell adhesion molecule 1/CD31.

RESULTS

Of the 34 tumors, 21 had clinicoradiologic evidence of lymphatic metastasis. Expression of VEGF-C was associated with lymphatic metastasis (P<.001), but not with microvessel density. The VEGF-A expression correlated with microvessel density (P<.001), but neither VEGF-A expression nor microvessel density was associated with lymphatic metastasis.

CONCLUSIONS

The expression of VEGF-C is associated with lymphatic metastasis in squamous cell carcinoma of the piriform fossa. This is not secondary to effects on vascular angiogenesis and is hypothesized to be due to effects on lymphatic endothelial cells.

Soluble Tie-2 receptor levels independently predict locoregional recurrence in head and neck squamous cell carcinoma

BACKGROUND

This study assessed two circulating angiogenic receptors as tumor markers in patients with head and neck squamous cell carcinoma (HNSCC): soluble vascular endothelial factor growth receptor-1 (sVEGFR1) and soluble Tie-2 receptor (sTie2R).

METHODS

Sera from 79 newly presenting patients with HNSCC and from 22 controls were assayed using sandwich ELISA. Median follow-up was 35 months after curative treatment. Analysis was carried out to compare levels between HNSCC patients and controls and to ascertain relationships with clinicopathologic and outcome variables.

RESULTS

Soluble VEGFR1 was not elevated in the HNSCC group and was not related to any of the clinicopathologic or outcome variables. Soluble Tie2R was also not elevated in HNSCC patients or related to the clinicopathologic variables but was associated with locoregional recurrence (p =.009). Raised sTie2R (>64 ng/mL) independently predicted recurrence (p =.007) with a relative risk of 3.0 (95% CI, 1.7-5.0).

CONCLUSIONS

Soluble Tie2R is an independent predictor of locoregional recurrence in HNSCC.

An audit of post-operative analgesia in children following tonsillectomy

Pain following tonsillectomy in children is a significant problem that tends to be underestimated. We audited post-operative pain in 33 children and found significant proportions of children in moderately severe to severe pain, particularly at, or soon after returning to the ward. These findings led to changes in practice that included the administration of pre-operative paracetamol and diclofenac as well as the uniform post-operative prescription of them, with printed instructions to reduce the scope for mistakes by medical staff. Other changes included a uniform policy, with which the nursing staff could become familiar, and the regular formal recording of pain to assist in the recognition of pain and analgesic requirements. On re-auditing two years later, in a group of 100 children, post-operative pain was significantly improved. The proportion experiencing moderately severe to severe pain on returning to the ward, as their maximum pain score and pain score at discharge fell from 70 per cent to 48 per cent, 85 per cent to 56 per cent, and six per cent to two per cent respectively.

Does flying after myringoplasty affect graft take rates?

Flying at altitude soon after myringoplasty may theoretically have an adverse effect on graft take rates owing to variation in external air pressure, together with suboptimal Eustachian tube function, causing graft displacement. We wished to assess the effect of flying after myringoplasty by comparing success rates of patients flying within a week postoperatively (n = 37) with a control group (n = 37) by carrying out a retrospective, controlled cohort study. The primary outcome measure was graft success, defined as a 100% closure at first outpatient follow-up (2.5 months). Our results showed that there was no difference in early graft success rates between the flying group (32/37: 86%) and non-flying group (29/37: 78%)(P = 0.32; 95% CI of difference: -9% to 27%). In conclusion, flying at altitude in a pressurized environment within a week of myringoplasty does not adversely affect early operative success.

Circulating angiogenic cytokines as tumour markers and prognostic factors in head and neck squamous cell carcinoma

This pilot study investigated the potential use of three circulating angiogenesis-related cytokines, basic fibroblast growth factor (bFGF), angiogenin (ANG) and endostatin, as tumour markers and prognostic factors in patients with head and neck squamous cell carcinoma (HNSCC). A total of 30 patients with HNSCC treated with curative intent and 15 healthy controls were studied. Serum (bFGF and ANG) and plasma (endostatin) was assayed by enzyme-linked immunoabsorbance assay (ELISA). None of the cytokines was raised in HNSCC patients when compared with controls. Serum bFGF was not associated with any clinico-pathological or outcome parameters, although there was a trend towards higher levels in more advanced and aggressive tumours. Lower serum angiogenin (sANG) levels were associated with loco-regional disease recurrence (P = 0.036). Using a cut-off level of 400 pg/mL, a low level of sANG predicted tumour recurrence with a relative risk of 4.0 (95% CI: 0.7-24.0). Plasma endostatin was associated with higher histological grade (P = 0.01) and with both disease recurrence (P = 0.045) and death from disease (P = 0.021). Plasma endostatin above a cut-off point of 70 ng/mL could predict tumour recurrence with a relative risk of 4.7 (95% CI: 1.1-19.7). These data suggest that plasma endostatin and sANG have potential roles as prognostic factors and require further investigation.

A quantitative analysis of the intranasal delivery of topical nasal drugs to the middle meatus: spray versus drop administration

The delivery of nasal drugs specifically to the middle meatus is of critical importance in the medical treatment of rhinosinusitis. In this respect, topical nasal drug administration by drops has generally been perceived to be superior to nasal sprays, although there is a lack of evidence to support this notion. This study aims to compare the intranasal delivery of nasal sprays and drops to the middle meatus in vivo, using a novel quantitative method. A surgical patty was placed in the middle meatus. Radio-labelled topical nasal drops and aqueous sprays were administered in a standardized fashion in normal volunteers (10 nasal cavities). The subsequent absorption of administered radio-labelled saline on the patty was measured using a gamma counter. A randomized prospective crossover design was used for the study. The mean percentage (range) of absorbed administered saline on the swab was 8.7 (0.3-39.5) and 9.7 (0.03-20.4) for the spray and drop administration techniques respectively (p = 0.8). Thus, there is wide variation in the delivery of topical nasal drugs and the perceived superiority of nasal drop administration, in terms of delivery to the middle meatus, may be incorrect.

The expression of vascular endothelial growth factor (VEGF) and VEGF-C in early laryngeal cancer: relationship with radioresistance

Angiogenesis is essential for tumour growth and invasion. Vascular endothelial growth factor (VEGF) is a prime mediator of tumour angiogenesis. VEGF-C is a closely related protein that effects lymphatic endothelial cells and may be important in the process of lymphatic metastasis. The purpose of this study was to evaluate the expression of these cytokines in patients with T1 and T2a glottic, squamous cell carcinoma, in comparison with normal epithelial control tissue, to ascertain any association with radioresistance. Twenty-two tumours treated by radiotherapy (13 radiosensitive, nine radioresistant) and seven normal control tissues were studied. The minimum follow-up was 2 years after radiotherapy. Expression of VEGF and VEGF-C was evaluated by immunohistochemistry of formalin-fixed, paraffin-embedded biopsy specimens. Analysis was carried out using a quantitative computer image analyser. Both VEGF and VEGF-C were detectable in tumour and normal control specimens. There was increased expression in tumour specimens of both VEGF (P = 0.03) and VEGF-C (P < 0.001). In addition, the expression of VEGF-C was associated with tumours of higher histological grade (P = 0.021). There was, however, no difference in VEGF and VEGF-C expression between radioresistant and radiosensitive tumours. The expression of VEGF and VEGF-C is increased in early laryngeal squamous cell carcinoma (SCC). However, measuring the expression of these proteins cannot predict radioresistance in this tumour group.