The observation of starch digestion in blue mussel Mytilus galloprovincialis exposed to microplastic particles under varied food conditions.

Microplastic continues to be an environmental concern, especially for filter feeding bivalves known to ingest these particles. It is important to understand the effects of microplastic particles on the physiological performance of these bivalves and many studies have investigated their impact on various physiological processes. This study investigated the effects of microplastic (10 µm) on digestive enzyme (amylase) activity of Mytilus galloprovincialis at 55,000 and 110,000 microplastic particles/L under laboratory conditions. Additionally, our study measured the expression of an isoform of Hsp70 in the gills to assess whether or not these particles may cause protein denaturation. Results revealed that this regime negatively affect the ability of M. galloprovincialis to digest starch under high food conditions but not low food conditions. Exposure to extreme levels of microplastic raised amylase activity. Furthermore, Hsp70 transcript abundance was not elevated in treatment mussels. These results show that mussels may be resilient to current microplastic pollution levels in nature.

Transient receptor potential channels TRPC1/TRPC6 regulate lamina cribrosa cell extracellular matrix gene transcription and proliferation.

The lamina cribrosa (LC) in glaucoma is with augmented production of extracellular matrix proteins (ECM) and connective tissue fibrosis. Fundamental pathological mechanisms for this fibrosis comprise fibrotic growth factors and oxidative stress. Transient receptor potential canonical channels (TRPC) channels play a key role in ECM fibrosis. Here, we study TRPC expression in glaucomatous LC cells, and investigate the role of TRPC in oxidative stress induced-profibrotic ECM gene transcription and cell proliferation in normal LC cells. Age-matched human LC cells (normal, n = 3 donors; glaucoma, n = 3 donors) were used. Hydrogen peroxide (H2O2, 100 µM), was used to induce oxidative stress in LC cells in the presence or absence of the pan TRPC inhibitor SKF96365 (10 µM) or knockdown of TRPC1/6 with siRNA. After treatments, ECM gene transcription, LC cell viability and proliferation and the phosphorylation of the transcription factor NFATc3, were measured using real time RT-PCR, colorimetric cell counting with the methyl-thiazolyl tetrazolium salt (MTS) assay, and Western immunoblotting, respectively. Results showed that TRPC1/C6 transcript and protein expression levels were significantly (p < 0.05) enhanced in glaucoma LC cells. Both SKF96365 and siRNA-TRPC1/C6 treatments significantly reduced the oxidative stress induced-ECM gene expression (transforming growth factor-ß1 (TGFß1), alpha smooth muscle actin (α-SMA), and collagen type 1A1 (Col1A1)), and cell proliferation in normal and glaucoma LC cells. Also, SKF96365 treatment inhibited the H2O2-induced NFATc3 protein dephosphorylation in LC cells. In conclusion, TRPC1/C6 expression is enhanced in glaucoma LC cells. These channels may contribute to oxidative stress-induced ECM gene transcription and cell proliferation in normal and glaucoma LC cells through Ca2+-NFATc3 signaling pathway mechanism. TRPC1 and TRPC6 channels could be important therapeutic targets to prevent ECM remodeling and fibrosis development in glaucoma optic neuropathy.

Modulating non-native aggregation and electrostatic protein-protein interactions with computationally designed single-point mutations.

Non-native protein aggregation is a ubiquitous challenge in the production, storage and administration of protein-based biotherapeutics. This study focuses on altering electrostatic protein-protein interactions as a strategy to modulate aggregation propensity in terms of temperature-dependent aggregation rates, using single-charge variants of human γ-D crystallin. Molecular models were combined to predict amino acid substitutions that would modulate protein-protein interactions with minimal effects on conformational stability. Experimental protein-protein interactions were quantified by the Kirkwood-Buff integrals (G22) from laser scattering, and G22 showed semi-quantitative agreement with model predictions. Experimental initial-rates for aggregation showed that increased (decreased) repulsive interactions led to significantly increased (decreased) aggregation resistance, even based solely on single-point mutations. However, in the case of a particular amino acid (E17), the aggregation mechanism was altered by substitution with R or K, and this greatly mitigated improvements in aggregation resistance. The results illustrate that predictions based on native protein-protein interactions can provide a useful design target for engineering aggregation resistance; however, this approach needs to be balanced with consideration of how mutations can impact aggregation mechanisms.

Evaluation of the Effect of Hypercapnia on Vascular Function in Normal Tension Glaucoma.

INTRODUCTION: Altered ocular perfusion and vascular dysregulation have been reported in glaucoma. The aim of this paper was to evaluate the vascular response to a hypercapnic stimulus. METHODS: Twenty normal tension glaucoma (NTG) patients and eighteen age- and gender-matched controls had pulsatile ocular blood flow (POBF) measurements, systemic cardiovascular assessment, and laser Doppler digital blood flow (DBF) assessed. Measurements were taken at baseline, after 10-minutes rest, in the stable sitting and supine positions and following induction and stabilization of hypercapnia, which induced a 15% increase in end-tidal pCO2. The POBF response to hypercapnia was divided into high (>20%) and low responders (<20%). RESULTS: 65% of NTG patients had a greater than 41% increase in POBF following CO2 rebreathing (high responders). These high responders had a lower baseline POBF, lower baseline DBF, and a greater DBF response to thermal stimulus. CONCLUSION: NTG patients that have a greater than 20% increase in POBF after a hypercapnic stimulus have lower baseline POBF and DBF values. This suggests that there is impaired regulation of blood flow in a significant subgroup of NTG patients. This observation may reflect a generalised dysfunction of the vascular endothelium.

Calcium channel blockade reduces mechanical strain-induced extracellular matrix gene response in lamina cribrosa cells.

PURPOSE: This study examines the effect of the L-type calcium channel blocker verapamil on mechanical strain-induced extracellular matrix genes in optic nerve head lamina cribrosa (LC) cells. METHODS: Changes in LC cell intracellular calcium [Ca(2+)]i following hypotonic cell membrane stretch were measured with the fluorescent probe fura-2/AM. Fluorescence intensity was measured, after labelling, by calcium (Ca2+) imaging confocal microscopy. Confluent human LC cell cultures were serum starved for 24 h prior to exposure to cyclical mechanical strain (1 Hz, 15%) for 24 h in the presence or absence of verapamil (10 mm). Transforming growth factor-ß 1 (TGF-ß1), collagen 6A3 (COL6A3) and chondroitin sulfate proteoglycan 2 (CSPG2) mRNA expression levels were assessed by quantitative RT-PCR. RESULTS: Hypotonic cell membrane stretch of LC cells from normal donors significantly increased [Ca2+]i (p<0.05). Exposure to cyclical mechanical strain (15% strain) produced a statistically significant increase in the three matrix genes that were examined (TGF-ß1, COL6A3 and CSPG2). This response in both cyclical and mechanical stretch was significantly reduced by pretreating LC cells with the L-type calcium channel blocker verapamil (p<0.05). CONCLUSIONS: This study provides evidence of a novel mechanotransduction pathway linking mechanical strain, cation channel function and the induction of LC cell matrix gene transcription. This highlights the potential involvement of calcium influx in the activation of matrix remodelling responses in the optic nerve head and supports the rationale that calcium channel blockers may attenuate disease progression in glaucoma.

Free energies of (Co, Fe, Ni, Zn)Fe2O4 spinels and oxides in water at high temperatures and pressure from density functional theory: results for stoichiometric NiO and NiFe2O4 surfaces.

A set of effective chemical potentials (ECPs) are derived that connect energies of (Co, Fe, Ni, Zn)Fe2O4 spinels and oxides calculated at 0 K from density functional theory (DFT) to free energies in high temperature and pressure water. The ECPs are derived and validated by solving a system of linear equations that combine DFT and experimental free energies for NiO, ZnO, Fe2O3, Fe3O4, FeO(OH), CoFe2O4, ZnFe2O4, NiFe2O4 and H2O. To connect to solution phase chemistry, a set of ECPs are also derived for solvated Ni(2+), Zn(2+), Fe(2+) and Fe(3+) ions using an analogous set of linear equations and the solid ECPs. The ECPs are used to calculate free energies of low index stoichiometric surfaces of nickel oxide (NiO) and nickel ferrite (NiFe2O4) in water as a function of temperature from 300 to 600 K at a pressure of 155 bar. Surface denuding at high temperatures is predicted, the implications of which for the formation of oxide corrosion products on heat transfer surfaces in light-water nuclear reactors are discussed.

Oxidative stress, mitochondrial dysfunction and calcium overload in human lamina cribrosa cells from glaucoma donors.

PURPOSE: Oxidative stress is implicit in the pathological changes associated with glaucoma. The purpose of this study was to compare levels of oxidative stress in glial fibrillary acid-negative protein (GFAP) lamina cribrosa (LC) cells obtained from the optic nerve head (ONH) region of 5 normal (NLC) and 4 glaucomatous (GLC) human donor eyes and to also examine mitochondrial function and calcium homeostasis in this region of the ONH. METHODS: Intracellular reactive oxygen species (ROS) production was examined by a thiobarbituric acid reactive substances (TBARS) assay which measures malondialdehyde (MDA), a naturally occurring product of lipid peroxidation and is used as an indicator of oxidative stress. Mitochondrial membrane potential (MMP) and intracellular calcium ([Ca(2+)](i)) levels were evaluated by flow cytometry using the JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetrabenzimidazolecarbocyanine iodide) and fluo-4/AM probes respectively. Anti-oxidant and Ca(2+) transport system gene and protein expression were determined by real time polymerase chain reaction (RT-PCR) using gene-specific primer/probe sets and western immunoblotting, respectively. RESULTS: Intracellular ROS production was increased in GLC compared to NLC (27.19 ± 7.05 µM MDA versus 14.59 ± 0.82 µM MDA, p < 0.05). Expression of the anti-oxidants Aldo-keto reductase family 1 member C1 (AKR1C1) and Glutamate cysteine ligase catalytic subunit (GCLC) were significantly lower in GLC (p = 0.02) compared to NLC control. MMP was lower in GLC (57.5 ± 6.8%) compared to NLC (41.8 ± 5.3%). [Ca(2+)](i) levels were found to be higher (p < 0.001) in GLC cells compared to NLC. Expression of the plasma membrane Ca(2+)/ATPase (PMCA) and the sodium-calcium (NCX) exchangers were lower, while intracellular sarco-endoplasmic reticulum Ca(2+)/ATPase 3 (SERCA) expression was significantly higher in GLC compared to NLC. Subjection of NLC cells to oxidative stress (200 µM H(2)0(2)) reduced expression of Na(+)/Ca2(+) exchanger 1 (NCX 1), plasma membrane Ca2+ ATPase 1 (PMCA 1), and PMCA 4 as determined by RT-PCR. CONCLUSIONS: Our data finds evidence of oxidative stress, mitochondrial dysfunction and impaired calcium extrusion in GLC cells compared to NLC cells and suggests their importance in the pathological changes occurring at the ONH in glaucoma. Future therapies may target reducing oxidative stress and / or [Ca(2+)](i).

Human papillomavirus predicts outcome in oropharyngeal cancer in patients treated primarily with surgery or radiation therapy.

OBJECTIVE: This study examines the prognostic significance of human papillomavirus (HPV) in patients with locally advanced oropharyngeal squamous cell carcinoma (SCC) treated primarily with surgery or definitive radiotherapy. METHODS: One hundred and ninety-eight patients with Stage 3/4 SCC were followed up for recurrence in any form or death from any cause for between 1 and 235 months after diagnosis. HPV status was determined using HPV E6-targeted multiplex real-time PCR/p16 immunohistochemistry. Determinants of recurrence and mortality hazards were modelled using Cox's regression with censoring at follow-up dates. RESULTS: Forty-two per cent of cancers were HPV-positive (87% type 16). HPV predicted loco-regional control, event-free survival and overall survival in multivariable analysis. Within the surgery with adjuvant radiotherapy (n=110), definitive radiotherapy-alone (n=24) and definitive radiotherapy with chemotherapy (n=47) groups, patients with HPV-positive cancers were one-third or less as likely to have loco-regional recurrence, an event or to die of any cause as those with HPV-negative cancers after adjusting for age, gender, tumour grade, AJCC stage and primary site. The 14 patients treated with surgery alone were considered too few for multivariable analysis. CONCLUSION: HPV status predicts better outcome in oropharyngeal cancer treated with surgery plus adjuvant radiotherapy as well as with definitive radiation therapy±chemotherapy.

Oestrogen receptor beta expression in pleomorphic adenomas of the parotid gland.

AIMS: Pleomorphic adenomas of the salivary gland have gender and age distributions suggesting that oestrogen has a causal role. However, oestrogen receptor (ER)alpha is expressed at low levels in normal salivary gland tissues and data from salivary gland tumours are conflicting. There is preliminary evidence that the recently described ERbeta may be the major ER in salivary gland tissue. The aim of this study was to determine the nature and extent of ERbeta expression in pleomorphic adenomas of the salivary gland. METHODS: Pleomorphic adenomas and normal tissues of the parotid gland from 49 patients were tested for ERalpha and ERbeta expression by semiquantitative immunohistochemistry. Associations were sought with patient age and gender. RESULTS: ERalpha and ERbeta expression was localised mainly to the nuclei of ductal cells in normal tissues and the epithelial components in pleomorphic adenomas. Within each tissue and receptor type there were no associations between ER positivity and patient age or gender. ERbeta was expressed in almost twice as many normal tissues and pleomorphic adenomas as ERalpha. Expression of ERbeta was also significantly higher in tumour compared with normal tissues. CONCLUSIONS: This is thought to be the first study of ERbeta in pleomorphic adenomas of the salivary gland. Findings support ERbeta as the major ER in salivary glands, and provide evidence that ERbeta may have a role in the development of pleomorphic adenomas of the salivary gland.

Risk factors for low BMD in healthy men age 50 years or older: a systematic review.

SUMMARY: In this systematic review, we summarize risk factors for low bone mineral density and bone loss in healthy men age 50 years or older. Consistent risk factors were: age, smoking, low weight, physical/functional limitations, and previous fracture. Data specific to men has clinical and policy implications. INTRODUCTION: Osteoporosis is a significant health care problem in men as well as women, yet the majority of evidence on diagnosis and management of osteoporosis is focused on postmenopausal women. The objective of this systematic review is to examine risk factors for low bone mineral density (BMD) and bone loss in healthy men age 50 years or older. MATERIALS AND METHODS: A systematic search for observational studies was conducted in MEDLINE, Cochrane Database of Systematic Reviews, DARE, CENTRAL, CINAHL and Embase, Health STAR. The three main search concepts were bone density, densitometry, and risk factors. Trained reviewers assessed articles using a priori criteria. RESULTS: Of 642 screened abstracts, 299 articles required a full review, and 25 remained in the final assessment. Consistent risk factors for low BMD/bone loss were: advancing age, smoking, and low weight/weight loss. Although less evidence was available, physical/functional limitations and prevalent fracture (after age 50) were also associated with low BMD/bone loss. The evidence was inconsistent or weak for physical activity, alcohol consumption, calcium intake, muscle strength, family history of fracture/osteoporosis, and height/height loss. CONCLUSION: In this systematic review, we identified several risk factors for low BMD/bone loss in men that are measurable in primary practice.

Cyclin D1 and p16 expression in pleomorphic adenoma and carcinoma ex pleomorphic adenoma of the parotid gland.

AIMS: To compare cyclin D1 and p16(ink4) (p16) expression in normal tissue, pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma (CXPA) of the parotid gland. METHODS AND RESULTS: Immunohistochemistry was used to examine cyclin D1 and p16 expression in 43 parotid tumours (29 PAs and 14 CXPAs). Cyclin D1 and p16 were both significantly more likely to be expressed in the neoplastic than in the normal epithelial and stromal components of PA and CXPA (P < 0.001 and P < 0.005, respectively). Cyclin D1 was more likely to be expressed in the malignant components of CXPA than in the benign components of PA (50% versus 31% and 31%, respectively), but the trend was not statistically significant. There was no evidence of this association for p16 (corresponding positivity rates 69% versus 81% and 52%). CONCLUSIONS: Our findings provide preliminary evidence of roles for cyclin D1 and p16 in the development of PA and for cyclin D1 in the progression of PA to CXPA.

Cyclin A expression and its diagnostic value in pleomorphic adenoma and carcinoma expleomorphic adenoma of the parotid gland.

AIMS: To investigate cyclin A expression in pleomorphic adenoma (PA) and carcinoma expleomorphic adenoma (CXPA) of the parotid gland with a view to assessing its potential value as a diagnostic marker for CXPA. METHODS AND RESULTS: Cyclin A expression in PA and CXPA was studied using semiquantitative immunohistochemistry. The epithelial component of the tumours expressed cyclin A in a statistically significantly (P < 0.005) higher number of CXPA cases (86%) compared with the PA cases (39%). Cyclin A was not expressed in normal salivary tissues of PA and CXPA. CONCLUSIONS: High cyclin A expression is a useful marker for the pathological diagnosis of CXPA.

Measures of health-related quality of life and functional status in survivors of oral cavity cancer who have had defects reconstructed with radial forearm free flaps.

The aim of this study was to evaluate (by postal questionnaire) quality of life and function in patients who have had resections of oral cancer and reconstruction by radial forearm flaps. Between October 1987 and December 2002, 258 patients had reconstructions by radial forearm flaps after resection of tumours in the oral cavity. Of these, 139 surviving patients were identified from the database and were sent questionnaires comprising five sections: Functional Assessment of Cancer Therapy-General (FACT-G) and -Head and Neck (FACT-HN); University of Washington Quality of Life Scale (UWQoL); Performance Status Scale for Head and Neck Cancer (PSS-HN); and the final section addressed dental rehabilitation and morbidity at the donor site. Sixty-three questionnaires (45%) were returned. In 17 (27%), parts of the questionnaire were incomplete. The median UWQoL score was 623/900, FACT-G was 92/108, FACT-HN was 31/48, and PSS-HN showed that eating in public, understandability of speech and normality of diet were 75/100, 75/100 and 50/100, respectively. The effect of stage and site on quality of life and function did not reach statistical significance. The effect of radiotherapy on speech (p=0.036) and diet (p=0.007) was significant. Patients who worried about their cancer returning had a lower UWQoL score (p=0.016). Ninety percent regarded their arm as disfigured, but 81% felt comfortable wearing short-sleeved shirts. Sensation and function of the hand were reported as normal in 87 and 92%, respectively. We conclude that patients who have had oral cancer have a persistent reduction in quality of life and function long after completion of treatment. The effects can be assessed by postal questionnaire, but the low rate of return (45%) and difficulties with completion reduce the quality of the data. Quality of life and function are essential components of improvements in outcome.

Trends in ophthalmic surgery in Ireland.

AIMS: This study was designed to document the changing trends in ophthalmic surgery in acute public hospitals in the Republic of Ireland over the years 1994 to 2001. METHOD: We obtained Hospital In-Patient Enquiry (HIPE) data returned from the major acute public hospitals to the Economic and Social Research Institute. We searched for cataracts, glaucoma, retinal detachment, strabismus, corneal transplant and repair of perforating injuries of the globe. RESULTS: There was a 24% increase in the total number of the searched operations occurring during the study period, from 8,857 procedures in 1994 to 11,005 in 2001. In 2001, cataract surgery alone counted for 82% of all procedures performed. There was a large increase in cataract (49%) and vitreo-retinal procedures (41%) reported between 1994 and 2001. Conversely, a large fall in trabeculectomy (67%), strabismus (63%) and corneal transplant (52%) procedures occurred during the study period. CONCLUSION: These data suggest that surgical numbers in ophthalmology in Ireland are increasing and the relative proportions are changing.

Clinical outcome and technical aspects of 263 radial forearm free flaps used in reconstruction of the oral cavity.

BACKGROUND: The aim of this study was to report the applications, complications, and limitations of the radial forearm flap when used for reconstruction after excision of cancers in the mouth. PATIENTS AND METHODS: We reviewed records in our database from October 1987 to December 2002; a total of 505 patients had surgical defects of the head and neck reconstructed with a radial forearm flap: 258 patients had oral cancers, of whom 173 were men and 85 women, median age was 70 years. Five patients had two reconstructions (total 263), of which 247 were fasciocutaneous and 16 osseofasciocutaneous flaps. Mucosal squamous carcinoma accounted for 97% of the primary cancers. RESULTS: There were nine failures of the flap (3.4%) and four episodes of partial necrosis. Four patients (2%) died within 30 days of operation. Orocutaneous fistulas appeared in nine patients (3.4%), 10 patients had wound infections, and nine had haematomas. The nine failed flaps were replaced by a second free flap in one patient, a pectoralis major flap in three, a buccinator myomucosal flap in one, a skin graft in one, and the remaining three defects healed by secondary intention. There was one failure and one partial failure among the 16 osseofasciocutaneous flaps.

Management of the neck in patients with T1 and T2 cancer in the mouth.

UNLABELLED: Our aim in this retrospective study was to evaluate the extent of control of metastatic disease in the neck and the survival of patients with T1 and T2 oral cancer. METHODS: All 171 patients with T1 and T2 squamous cell carcinoma (SCC) in the mouth were identified from our computerised database. All had had primary tumours resected and 21 patients with palpable neck nodes had therapeutic neck dissections. Among 150 patients with no palpable nodes, 75 had elective neck dissections, and 75 were observed. The decision to do an elective neck dissection was based on clinical criteria and was not randomised. RESULTS: Cervical nodes contained metastases in 17 of 21 patients who had therapeutic, and 27 of 75 who had elective, neck dissections. Neck metastases developed subsequently in 15 of 75 patients in the observed group, and 9 of these were salvaged by therapeutic neck dissection. The 5-year disease free survival was 19/21 after therapeutic dissection, 72/75 after elective dissection, and 69/75 in the observed group. Patients with cervical nodal metastases had significantly reduced 5-year survival compared with those without (63% and 91%, P = 0.003).

Three dimensional analysis of the lamina cribrosa in glaucoma.

BACKGROUND/AIM: Structural changes in the lamina cribrosa have been implicated in the pathogenesis of glaucomatous optic atrophy. The aim of this study was to determine a measure the surface variability of the cup floor in normal subjects and patients with glaucoma. METHODS: A sample of age matched normal subjects (NN), patients with low tension glaucoma (LTG), and primary open angle glaucoma (POAG) were included in the study. The glaucoma groups were matched for the severity of the visual field loss. Mean 10 degree topographic images of normal and glaucomatous eyes from the Heidelberg retina tomograph were imported into ERDAS image processing software where topographic analysis of the cup floor could be assessed. Each image was processed using customised spatial filters that calculated the surface depth variation in localised neighbourhood areas across each image. The local change in depth across the cup floor surface was determined and compared between the three clinical groups. RESULTS: The depth variation in the cup floor was largest in normal subjects followed by LTG and POAG. Highly statistically significant differences in surface depth variability of the cup floor existed between normal and LTG (p = 0.005), between normal and POAG (p<0.0001), and between LTG and POAG groups (p<0.0001). The variability and skewness of depth difference across the optic cup floor were also significantly different between the three clinical groups. CONCLUSION: A new parameter quantifying depth variations in the cup floor significantly discriminated between groups of normal and glaucoma patients. This new parameter may contribute to a better understanding of the pathogenesis of the glaucomatous optic nerve damage in different types of glaucoma.

Total thyroidectomy for clinically benign disease of the thyroid gland.

BACKGROUND: The role of total thyroidectomy in the treatment of patients with benign thyroid disease remains controversial. However, this procedure may be appropriate when both thyroid lobes are involved and when the risk of recurrence is significant. This study is a review of a 15-year experience of total thyroidectomy for benign disease. METHODS: Between 1988 and 2002, 834 patients underwent total thyroidectomy for clinically benign disease at the Sydney Head and Neck Cancer Institute, Royal Prince Alfred Hospital. There were 128 men and 706 women with a mean age of 52 (range 16-91) years. Indications for surgery were euthyroid multinodular goitre (MNG), toxic MNG and Graves' disease in 730 (87.5 per cent), 57 (6.8 per cent) and 47 (5.6 per cent) respectively. A total of 74 patients had previously undergone partial thyroidectomy. RESULTS: The incidence of temporary recurrent laryngeal nerve palsy was 2.3 per cent and that of temporary hypoparathyroidism 14.4 per cent. Permanent recurrent laryngeal nerve palsy occurred in 1.1 per cent, and 2.4 per cent of patients had permanent hypoparathyroidism. Neither the initial clinical diagnosis nor a history of previous treatment significantly influenced the rate of complications. The incidence of malignancy, other than incidental microscopic papillary carcinoma, was 4.6 per cent. CONCLUSION: Total thyroidectomy has an important role in the management of patients with benign disease when both lobes of the thyroid gland are involved. This approach avoids disease recurrence and the increased risk of morbidity associated with secondary operation.

Influence of condition of surgical margins on local recurrence and disease-specific survival in oral and oropharyngeal cancer.

BACKGROUND: The clearance of surgical margins at the primary site is widely thought to influence the subsequent course of the disease in patients operated on for oral and oropharyngeal carcinoma. In some reports the adverse impact of close or involved margins was not negated by postoperative radiotherapy. These findings, in addition to descriptive histopathological studies, have led some authors to recommend margins of more than a macroscopic clearance of 1cm at certain subsites. We have therefore examined the relation between the condition of surgical margins and local recurrence and disease-specific survival. METHODS: Identical treatment protocols were used to treat two independent groups of patients (Sydney, Australia, n=237; Lanarkshire, n=95) who presented with previously untreated carcinoma of the mouth or oropharynx. All patients were operated on with the primary objective of achieving a macroscopic clearance of 1cm. Postoperative radiotherapy was used according to a protocol. Data about patients were entered into comprehensive computerised databases prospectively. Known clinical and pathological prognostic indicators, in addition to the condition of surgical margins, were analysed to find out if they were predictive of local recurrence and disease-specific survival using the Cox proportional hazard model. RESULTS: Local recurrence was predicted by the presence of perineural invasion at the primary site in both groups. Disease-specific survival was predicted by the presence and extent of regional lymph node metastases in both groups. The condition of surgical margins (clear, close, or involved) did not predict local recurrence, or disease-specific survival on multivariate analysis. CONCLUSIONS: A macroscopic margin of 1cm seems adequate in the surgical management of oral and oropharyngeal carcinoma. For most patients who have close or involved margins the biology of the disease influences the subsequent course irrespective of the width of clearance of tumour.

Evaluation of a protocol for examining nephrectomy specimens with renal cell carcinoma.

AIMS: To evaluate the practicality of use and the effectiveness of a standard protocol for examining nephrectomy specimens for renal cell carcinoma (RCC), with emphasis on the identification of vascular invasion. METHODS: A standard protocol, devised to identify the major prognostic determinants, was used to examine 79 consecutive tumours submitted to four histopathology departments. The incidence of vascular invasion found was compared with the incidence in a historical series of tumours. RESULTS: The protocol proved easy to follow, and appeared to increase the incidence of observed vascular invasion (40 of 69 cases compared with 69 of 176 cases in the historical series; p = 0.059, Fishers exact test, one sided) CONCLUSIONS: If pathological prognostic determinants are to be used for clinical management, then it is important that they are identified and recorded consistently. The protocol described provides a method of examining nephrectomy specimens that can be used in routine practice and would probably reliably identify recognised prognostic variables.