Effectiveness of preoperative staging in rectal cancer: digital rectal examination, endoluminal ultrasound or magnetic resonance imaging?

In rectal cancer, preoperative staging should identify early tumours suitable for treatment by surgery alone and locally advanced tumours that require therapy to induce tumour regression from the potential resection margin. Currently, local staging can be performed by digital rectal examination (DRE), endoluminal ultrasound (EUS) or magnetic resonance imaging (MRI). Each staging method was compared for clinical benefit and cost-effectiveness. The accuracy of high-resolution MRI, DRE and EUS in identifying favourable, unfavourable and locally advanced rectal carcinomas in 98 patients undergoing total mesorectal excision was compared prospectively against the resection specimen pathological as the gold standard. Agreement between each staging modality with pathology assessment of tumour favourability was calculated with the chance-corrected agreement given as the kappa statistic, based on marginal homogenised data. Differences in effectiveness of the staging modalities were compared with differences in costs of the staging modalities to generate cost effectiveness ratios. Agreement between staging and histologic assessment of tumour favourability was 94% for MRI (kappa=0.81, s.e.=0.05; kappa(W)=0.83), compared with very poor agreements of 65% for DRE (kappa=0.08, s.e.=0.068, kappa(W)=0.16) and 69% for EUS (kappa=0.17, s.e.=0.065, kappa(W)=0.17). The resource benefits resulting from the use of MRI rather than DRE was 67164 UK pounds and 92244 UK pounds when MRI was used rather than EUS. Magnetic resonance imaging dominated both DRE and EUS on cost and clinical effectiveness by selecting appropriate patients for neoadjuvant therapy and justifies its use for local staging of rectal cancer patients

Excitatory effect of ATP on rat area postrema neurons

ATP-induced inward currents and increases in the cytosolic Ca2+ concentration ([Ca]in) were investigated in neurons acutely dissociated from rat area postrema using whole-cell patch-clamp recordings and fura-2 microfluorometry, respectively. The ATP-induced current (IATP) and [Ca]in increases were mimicked by 2-methylthio-ATP and ATP-γS, and were inhibited by P2X receptor (P2XR) antagonists. The current–voltage relationship of the IATP exhibited a strong inward rectification, and the amplitude of the IATP was concentration-dependent. The IATP was markedly reduced in the absence of external Na+, and the addition of Ca2+ to Na+-free saline increased the IATP. ATP did not increase [Ca]in in the absence of external Ca2+, and Ca2+ channel antagonists partially inhibited the ATP-induced [Ca]in increase, indicating that ATP increases [Ca]in by Ca2+ influx through both P2XR channels and voltage-dependent Ca2+ channels. There was a negative interaction between P2XR- and nicotinic ACh receptor (nAChR)-channels, which depended on the amplitude and direction of current flow through either channel. Current occlusion was observed at Vhs between −70 and −10 mV when the IATP and ACh-induced current (IACh) were inward, but no occlusion was observed when these currents were outward at a Vh of +40 mV. The IATP was not inhibited by co-application of ACh when the IACh was markedly decreased either by removal of permeant cations, by setting Vh close to the equilibrium potential of IACh, or by the addition of d-tubocurarine or serotonin. These results suggest that the inhibitory interaction is attributable to inward current flow of cations through the activated P2XR- and nAChR-channels

2010 SSO John Wayne Clinical Research Lecture: Rectal Cancer Outcome Improvements in Europe: Population-Based Outcome Registrations will Conquer the World

During the past two decades, rectal cancer treatment has improved considerably in Europe. Clinical trials played a crucial role in improving surgical techniques, (neo)adjuvant treatment schedules, imaging, and pathology. However, there is still a wide variation in outcome after rectal cancer. In most western health care systems, efforts are made to reduce hospital variation by focusing on selective referral and encouraging patients to seek care in high-volume hospitals. On the other hand, the expertise for diagnosis and treatment of common types of cancer should be preferably widespread and easily accessible for all patients. As an alternative to volume-based referral, hospitals and surgeons can improve their results by learning from their own outcome statistics and those from colleagues treating a similar patient group. Several European surgical (colo)rectal audits have led to improvements with a greater impact than any of the adjuvant therapies currently under study. However, differences remain between European countries, which cannot be easily explained. To generate the best care for colorectal cancer in the whole of Europe and to meet political and public demands for transparency, the European CanCer Organisation (ECCO) initiated an international, multidisciplinary, outcome-based quality improvement program: European Registration of Cancer Care (EURECCA). The goal is to create a multidisciplinary European registration structure for patient, tumor, and treatment characteristics linked to outcome registration. Clinical trials will always play a major role in improving rectal cancer treatment. To further improve outcomes and diminish variation, EURECCA will establish the basis for a strong, multidisciplinary, international audit structure that can be used as a template for similar projects worldwide

Randomized scheduling feasibility study of S-1 for adjuvant chemotherapy in advanced head and neck cancer

The purpose of this study was to determine the feasible adjuvant therapy administration schedule of S-1 for locoregionally advanced squamous cell carcinoma of the head and neck (SCCHN). Patients receiving definitive treatments were randomly assigned to either arm A (51 cases) receiving oral S-1 of 2-week administration followed by 1-week rest for 6 months, or arm B receiving S-1 of 4-week administration followed by 2-week rest for 6 months. Planned treatment was given in 40% of patients in arm A and 29% in arm B. The cumulative rates of the relative total administration dose of S-1 at 100% were 54.9% (95% CI: 40.1–69.7%) in arm A and 34.3% (95% CI: 21.1–47.4%) in arm B, respectively (P=0.054). Adverse events were recorded in 41 patients (82.0%) in arm A and 48 patients (94.1%) in arm B (P=0.060). The incidences of diarrhoea (10 vs 28%; P<0.05) and skin toxicities (18 vs 37%; P<0.05) were significantly higher in arm B. One-year disease-free survival was similar in both arms: arm A 81.2% (95% CI: 70.0–92.4%); arm B 77.0% (95% CI: 65.0–89.0%). The schedule of 2-week administration followed by 1-week rest seems to be more feasible for oral 6-month administration of S-1 in adjuvant chemotherapy of locoregionally advanced SCCHN

Chymase-Dependent Generation of Angiotensin II from Angiotensin-(1-12) in Human Atrial Tissue

Since angiotensin-(1-12) [Ang-(1-12)] is a non-renin dependent alternate precursor for the generation of cardiac Ang peptides in rat tissue, we investigated the metabolism of Ang-(1-12) by plasma membranes (PM) isolated from human atrial appendage tissue from nine patients undergoing cardiac surgery for primary control of atrial fibrillation (MAZE surgical procedure). PM was incubated with highly purified 125I-Ang-(1-12) at 37°C for 1 h with or without renin-angiotensin system (RAS) inhibitors [lisinopril for angiotensin converting enzyme (ACE), SCH39370 for neprilysin (NEP), MLN-4760 for ACE2 and chymostatin for chymase; 50 µM each]. 125I-Ang peptide fractions were identified by HPLC coupled to an inline γ-detector. In the absence of all RAS inhibitor, 125I-Ang-(1-12) was converted into Ang I (2±2%), Ang II (69±21%), Ang-(1-7) (5±2%), and Ang-(1-4) (2±1%). In the absence of all RAS inhibitor, only 22±10% of 125I-Ang-(1-12) was unmetabolized, whereas, in the presence of the all RAS inhibitors, 98±7% of 125I-Ang-(1-12) remained intact. The relative contribution of selective inhibition of ACE and chymase enzyme showed that 125I-Ang-(1-12) was primarily converted into Ang II (65±18%) by chymase while its hydrolysis into Ang II by ACE was significantly lower or undetectable. The activity of individual enzyme was calculated based on the amount of Ang II formation. These results showed very high chymase-mediated Ang II formation (28±3.1 fmol×min−1×mg−1, n = 9) from 125I-Ang-(1-12) and very low or undetectable Ang II formation by ACE (1.1±0.2 fmol×min−1×mg−1). Paralleling these findings, these tissues showed significant content of chymase protein that by immunocytochemistry were primarily localized in atrial cardiac myocytes. In conclusion, we demonstrate for the first time in human cardiac tissue a dominant role of cardiac chymase in the formation of Ang II from Ang-(1-12)

Role of tumor size in the pre-operative management of rectal cancer patients

Clinical management of rectal cancer patients relies on pre-operative staging. Studies however continue to report moderate degrees of over/understaging as well as inter-observer variability. The aim of this study was to determine the sensitivity, specificity and accuracy of tumor size for predicting T and N stages in pre-operatively untreated rectal cancers