Report from the 20th annual Western Canadian Gastrointestinal Cancer Consensus Conference; Saskatoon, Saskatchewan; 28-29 September 2018.

The 20th annual Western Canadian Gastrointestinal Cancer Consensus Conference was held in Saskatoon, Saskatchewan, 28-29 September 2018. This interactive multidisciplinary conference is attended by health care professionals from across Western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) who are involved in the care of patients with gastrointestinal cancers. In addition, invited speakers from other provinces participate. Surgical, medical, and radiation oncologists, and allied health care professionals participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancers.

Report from the 19th annual Western Canadian Gastrointestinal Cancer Consensus Conference; Winnipeg, Manitoba; 29-30 September 2017.

The 19th annual Western Canadian Gastrointestinal Cancer Consensus Conference (wcgccc) was held in Winnipeg, Manitoba, 29-30 September 2017. The wcgccc is an interactive multidisciplinary conference attended by health care professionals from across Western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) who are involved in the care of patients with gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancer.

Clinical characteristics and immunohistochemical analysis of p53, Ki-67 and cyclin D1 in 80 odontogenic keratocysts.

OBJECTIVE: The aim of this study was to evaluate clinical parameters and expression patterns of Ki-67, cyclin D1 and p53 in odontogenic keratocysts. MATERIAL AND METHODS: In this study, fifty-three patients with 80 odontogenic keratocysts were included. The medical records of these patients were reviewed retrospectively. To elucidate the molecular pathogenesis of the disease, the expression of p53, Ki-67 and cyclin D1 was analyzed using immunohistochemistry. RESULTS: A total of 53 patients (mean age 38 years) with a median follow-up of 4.2 years (ranging from 4 days to 14.4 years) were evaluated. The rates of recurrence and post-operative complications varied depending on the surgical approach: cystectomy and peripheral ostectomy led to manageable low rates of complications and recurrence frequency. Immunohistochemical evaluation revealed that all lesions were positive for Ki-67 and cyclin D1 expression. The expression of Ki-67 was associated with the degree of inflammation. Cyclin D1 was expressed significantly higher in syndrome-associated keratocystic lesions. In contrast to non-syndromal lesions, all syndromal lesions expressed p53. CONCLUSION: This investigation demonstrates that the pathogenesis of syndromal keratocysts appears to differ from sporadic odontogenic keratocysts. Additionally, the primary and recurrent non-syndromal keratocysts have a similar etiology, as no differences in the expression patterns of Ki-67, p53 and cyclin D1 were observed.

Expression of DNA damage response proteins in cervical cancer patients treated with radical chemoradiotherapy.

OBJECTIVE: The management of locally advanced cervical cancer has improved significantly with the advent of cisplatin-based chemoradiotherapy (CRT) as the primary treatment regimen. Nevertheless, a significant proportion of patients fail to respond or relapse on this treatment and have a very poor prognosis. Our goal was to determine the prognostic value of a panel of proteins involved in detection and repair of DNA damage. METHODS: We performed fluorescence immunohistochemistry, and used software analysis to assess expression of DNA damage response proteins ATM, DNA-PKcs, PARP-1, Ku70 and Ku86 in 117 pre-treatment specimens from patients with locally advanced cervical cancer. We compared expression to clinicopathologic correlates to determine prognostic significance. RESULTS: Five-year progression-free survival was significantly lower in the low expressors than in high expressors of ATM (35% vs. 58%, p=0.044) and PARP-1 (24% vs. 61%, p=0.003), and showed a trend to significance for DNA-PKcs (30% vs. 60%, p=0.050). Low expression of the same proteins also correlated significantly with lower overall survival. In multivariable analysis, adjusted for FIGO stage and tumor size, low ATM and PARP-1 expression was significantly associated with both poorer progression-free and overall survival. Pairwise analyses indicated that expression levels of these proteins were correlated. CONCLUSIONS: Expression of DNA damage response proteins in cervical cancer is associated with outcome in patients treated with CRT. Immunohistochemical analysis of these proteins may be useful in guiding treatment decisions in such patients.

Report from the 17th Annual Western Canadian Gastrointestinal Cancer Consensus Conference; Edmonton, Alberta; 11-12 September 2015.

The 17th annual Western Canadian Gastrointestinal Cancer Consensus Conference (wcgccc) was held in Edmonton, Alberta, 11-12 September 2015. The wcgccc is an interactive multidisciplinary conference attended by health care professionals from across Western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) who are involved in the care of patients with gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management of gastric cancer.

The changing landscape of brachytherapy for cervical cancer: a Canadian practice survey.

BACKGROUND: We documented changes in practice from 2009 to 2012 for cervical cancer brachytherapy in Canada. METHODS: Centres with gynecologic brachytherapy services were sent an e-mail questionnaire querying their 2012 practice. Responses are reported and compared with practice patterns identified in a similar survey for 2009. RESULTS: The response rate was 77% (24 of 31 centres). Almost all use high-dose-rate brachytherapy (92%); low-dose-rate brachytherapy has been completely phased out. Most continue to move patients from the site of applicator insertion to the radiation treatment simulation suite (75%) or to a diagnostic imaging department (29%), or both. In 2012, the imaging modalities used for dose specification were computed tomography [ct (75%)], magnetic resonance imaging [mri (38%)], plain radiography (21%), and cone-beam ct (8%). The number of institutions using mri guidance has markedly increased during the period of interest (9 vs. 1). Most respondents (58% vs. 14%) prescribed using guidelines from the Groupe Européen de Curiethérapie and the European Society for Therapeutic Radiology and Oncology, but they also used point A as a reference. Commonly used high-dose radiation regimens included 30 Gy in 5 fractions and 24 Gy in 3 fractions. CONCLUSIONS: In Canada, image-guided brachytherapy for cervical cancer continues to evolve. Although ct-based imaging remains the most commonly used modality, many centres have adopted mri for at least 1 brachytherapy treatment. More centres are using fewer fractions and a slightly lower biologically effective dose, but are still achieving EQD2 (2-Gy equivalent) doses of 80-90 Gy in combination with external-beam radiation therapy.

Clinical outcomes of elderly patients receiving neoadjuvant chemoradiation for locally advanced rectal cancer.

BACKGROUND: Studies of clinical outcomes of elderly patients treated with neoadjuvant chemoradiation (nCRT) for locally advanced rectal cancer (LARC) are limited. Our aim was to assess the impact of age on clinical outcomes in a large multi-institutional database. PATIENTS AND METHODS: Data for patients diagnosed with LARC who received nCRT and curative-intent surgery between 2005 and 2012 were collected from five major Canadian cancer centers. Age was analyzed as a continuous and dichotomous variable (< 70 versus ≥ 70 years) and correlated with disease-free survival (DFS), cancer-specific survival (CSS) and overall survival (OS). Cox regression models were used to adjust for important prognostic factors. RESULTS: Of 1172 patients included, 295 (25%) were ≥ 70 years, and they were less likely to receive adjuvant chemotherapy (ACT; 60% versus 79%, P < 0.0001), oxaliplatin-based ACT (12% versus 31%, P < 0.0001), less likely to complete nCT (76% versus 86%, P < 0.001), and more likely to be anemic at initiation of nCRT (42% versus 30%, P = 0.0004). In multivariate analyses, age ≥ 70 years was associated with similar DFS [hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.68-1.26, P = 0.63], similar CSS (HR 0.81, 95% CI 0.46-1.41, P = 0.45), and similar OS (HR 1.28, 95% CI 0.88-1.86, P = 0.20), compared with the younger age group. As a continuous variable, increasing age was not predictive of DFS (HR 1.00, 95% CI 0.99-1.02, P = 0.49) or CSS (HR 1.002, 95% CI 0.98-1.02, P = 0.88); however, it correlated with an inferior OS (HR 1.02, 95% CI 1.00-1.03, P = 0.04). CONCLUSIONS: Elderly patients (≥ 70 years) who receive nCRT followed by surgery appear to have similar outcomes compared with younger patients. Decisions regarding eligibility for nCRT and surgery should not be based on age alone.

Consensus statement: the 16th Annual Western Canadian Gastrointestinal Cancer Consensus Conference; Saskatoon, Saskatchewan; September 5-6, 2014.

The 16th annual Western Canadian Gastrointestinal Cancer Consensus Conference was held in Saskatoon, Saskatchewan, September 4-5, 2014. The Consensus Conference is an interactive, multidisciplinary event attended by health care professionals from across western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) involved in the care of gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancer.

One compared with two cycles of mitomycin C in chemoradiotherapy for anal cancer: analysis of outcomes and toxicity.

BACKGROUND: Concurrent chemoradiation with fluorouracil (5fu) and mitomycin C (mmc) is standard treatment for anal canal carcinoma (acc). The current protocol in Alberta is administration of 5fu and mmc during weeks 1 and 5 of radiation. However, administration of the second bolus of mmc has been based largely on centre preference. Given limited published data on outcomes with different mmc regimens, our objective was to compare the efficacy and toxicity of 1 compared with 2 cycles of mmc in acc treatment. METHODS: Our retrospective study evaluated 169 acc patients treated with radical chemoradiotherapy between 2000 and 2010 at two tertiary cancer centres. All patients were treated with 2 cycles of 5fu and with 1 cycle (mmc1) or 2 cycles (mmc2) of mmc. Acute toxicities, disease-free (dfs) and overall survival (os) were analyzed. RESULTS: Baseline demographics, performance status, and stage were similar in the groups of patients who received mmc1 (52%) and mmc2 (48%). Before treatment, median hematologic parameters were comparable, except for white blood cell count, which was higher in the mmc2 group, but within normal range. The 5-year os and dfs were similar (75.1% and 54.2% for mmc1 vs. 70.7% and 44.2% for mmc2, p = 0.98 and p = 0.63 respectively). On multivariate analysis, mmc2 was the factor most strongly associated with specific acute toxicities: grade 3+ leukopenia (hazard ratio: 4.82; p < 0.01), grade 3+ skin toxicity (hazard ratio: 4.76; p < 0.001), and hospitalizations secondary to febrile neutropenia (hazard ratio: 9.91; p = 0.001). CONCLUSIONS: In definitive chemoradiotherapy for acc, 1 cycle of mmc appears to offer outcomes similar to those achieved with 2 cycles, with significantly less acute toxicity.

Influence of experience and qualification on PET-based target volume delineation. When there is no expert--ask your colleague.

BACKGROUND AND PURPOSE: The integration of positron emission tomography (PET) information for target volume delineation in radiation treatment planning is routine in many centers. In contrast to automatic contouring, research on visual-manual delineation is scarce. The present study investigates the dependency of manual delineation on experience and qualification. PATIENTS AND METHODS: A total of 44 international interdisciplinary observers each defined a [(18)F]fluorodeoxyglucose (FDG)-PET based gross tumor volume (GTV) using the same PET/CT scan from a patient with lung cancer. The observers were "experts" (E; n = 3), "experienced interdisciplinary pairs" (EP; 9 teams of radiation oncologist (RO) + nuclear medicine physician (NP)), "single field specialists" (SFS; n = 13), and "students" (S; n = 10). Five automatic delineation methods (AM) were also included. Volume sizes and concordance indices within the groups (pCI) and relative to the experts (eCI) were calculated. RESULTS: E (pCI = 0.67) and EP (pCI = 0.53) showed a significantly higher agreement within the groups as compared to SFS (pCI = 0.43, p = 0.03, and p = 0.006). In relation to the experts, EP (eCI = 0.55) showed better concordance compared to SFS (eCI = 0.49) or S (eCI = 0.47). The intermethod variability of the AM (pCI = 0.44) was similar to that of SFS and S, showing poorer agreement with the experts (eCI = 0.35). CONCLUSION: The results suggest that interdisciplinary cooperation could be beneficial for consistent contouring. Joint delineation by a radiation oncologist and a nuclear medicine physician showed remarkable agreement and better concordance with the experts compared to other specialists. The relevant intermethod variability of the automatic algorithms underlines the need for further standardization and optimization in this field.

Positron-emission tomography for locally advanced cervical cancer: a survey assessing Canadian practice patterns and access.

PURPOSE: Imaging by fluorodeoxyglucose positron-emission tomography (pet) has emerged as a valuable tool in the management of locally advanced cervical cancer (lacc), both for assessment of lymph node status and determination of response to chemoradiotherapy. The aim of the present study was to survey Canadian radiation oncologists to determine access to pet imaging for lacc patients and to assess current patterns of practice. METHODS: Radiation oncology centres across Canada were contacted to identify radiation oncologists who treat patients with lacc. The focus of the survey was patients treated with radical chemoradiotherapy with curative intent. An anonymous online tool was used to distribute a 23-item questionnaire asking about access to pet imaging, opinions on indications for pet imaging, and practice patterns relating to the use of pet in this patient population. Questionnaire responses were tabulated and analyzed. RESULTS: The response rate was 65% (35 of 54 questionnaire recipients). Most respondents (80%) have access to pet for lacc patients, usually restricted to study protocols. Of the respondents,48% considered that access to pet was timely. Frequency of routine orders for pet before and after treatment (to assess response) was 63% and 15% respectively. With better access, 91% of respondents would routinely order pet before treatment, and 61% would routinely order it for posttreatment assessment. For initial staging, 85% of respondents considered pet to be a standard of care, and nearly half (45%) believed it should be a standard of care to assess treatment response. Because of access limitations, nearly 70% of respondents (23 of 34) do not order pet as often as they feel it is clinically indicated, and 74% agree that better access to pet would lead to improved care for lacc patients in Canada. CONCLUSIONS: Canadian radiation oncologists support the routine use of pet imaging in the initial workup of patients with lacc. Access to pet imaging limits routine use for these patients in clinically indicated situations. There is strong support for developing guidelines for pet use in this patient population.

Primary B-cell lymphoma of bone in children.

UNLABELLED: Primary lymphoma of bone (PLB) is a rare entity of extranodal non-Hodgkin lymphoma (NHL). We report on two children with PLB focussing on diagnostic evaluation and treatment strategy. Clinical and radiographic presentation in both children suggested a primary bone tumour such as Ewing sarcoma. A 13-year-old girl showed osteolytic tumours in the right 7th rib and right iliac crest. Additional skeletal lesions were found by whole-body positron emission tomography. A 6-year-old boy presented with an isolated, osteolytic lesion of the left distal femur. In both patients staging procedures excluded any organ involvement besides the skeletal tumours. Tumour biopsy and immunohistological studies revealed lymphoblastic non-Hodgkin lymphoma of B-cell lineage in both children. They received a polychemotherapy for B-cell lymphoma according to the NHL-BFM 95 protocol and are in complete remission with a follow up of 24 and 18 months respectively. CONCLUSION: Isolated, primary lymphoma of bone in children may clinically and radiographically impose as primary bone tumour. Multiple therapeutic strategies have been applied in the treatment of this malignancy, however, treatment modalities are not well focussed on immunological patterns in the case of primary lymphoma of bone. Staging techniques should include immunophenotyping to initiate specific cell lineage treatment.

The GRID Technique: Current Status and New Trends.

In the GRID technique one measures Doppler-broadened line profiles of γ transitions using the high resolution crystal spectrometers GAMS, which are installed at the high flux reactor of the ILL Grenoble. One of the essential applications of this technique is the measurement of nuclear state lifetimes. In the present contribution the precision and the principal limits of the technique are discussed.

Study of Interatomic Potentials Using the Crystal-GRID Method on Oriented Single Crystals of Ni, Fe, and Cr.

The Crystal-GRID method is used to study interatomic collisions at low energy in metals and such to probe the repulsive interatomic potential. Line shapes of gamma rays, emitted by the recoiling (59)Ni isotope after thermal neutron capture in Ni single crystals, were measured and compared to results obtained by molecular dynamics simulations of the slowing down. The same procedure is also used for recoiling (57)Fe and (54)Cr atoms in Fe and Cr single crystals, respectively. Different potentials (including several from the embedded atom method) are investigated using the observed fine structure of the line shape which depends on the crystal orientations. From the detailed study of the lineshapes measured in two different orientations, a new potential is then derived for each element. Nuclear state lifetimes for the excited isotopes are also deduced with a higher precision than obtained with standard nuclear techniques.

Lifetime Measurements in (178)Hf.

Lifetimes of levels from K(π) = 2(+), K(π) = 4(+) and several K(π) = 0(+) bands have been measured in the (178)Hf nucleus using the GRID technique. Lifetimes of the 2(+) and 3(+) levels were measured within the K(π) = 2(+) γ band. A lower limit was established for the lifetime of the 4(+) level of the K(π) = 4(+) band. The resulting upper limits for the absolute B(E2) values exclude collective transitions from the K(π) = 4(+) to the ground state band but not to the K(π)= 2(+) band. Level lifetimes were also measured for several states within three separate K(π)= 0(+) bands. Evidence is presented for a previously unobserved case of two excited K(π)= 0(+) bands being connected via collective E2 transitions.

GAMS5.

The construction of the double-crystal γ-spectrometer GAMS5 was finished recently and the instrument is now operational. Measurements with double flat crystals were carried out and we will report here on the progress concerning the characteristics of the spectrometer.

Functional assessment of cutaneous microvasculature after radiation.

BACKGROUND AND PURPOSE: To determine if laser Doppler flowmetry could be used to non-invasively evaluate microvasculature function after radiation therapy (RT), we assessed blood flow response to heating in women following RT after breast conservation. MATERIALS AND METHODS: Forty women with unilateral stage I/II breast cancer treated with conservative surgery and RT were evaluated at varying intervals post RT. Ten patients were retested after an interval of 55 to 57 months to assess reproducibility of the control data. A laser Doppler probe fitted into a heat source was used to non-invasively measure blood flow in a small area of skin on the treated breast and a matched area on the untreated side. The heating element increased skin surface temperature to 40 degrees C, permitting assessment of heat stress induced changes in blood flow. RESULTS: Blood flow increased in response to heating in the untreated and treated breast skin, however the magnitude of the increase was significantly greater in the non-irradiated skin. The difference in relative blood flow to the heat stress was found to be greatest in patients < or =6 months post RT. In the patients who were >36 months post RT, there was no significant difference seen in relative blood flow between the irradiated and non-irradiated sides. Cutaneous blood flow response to the heat stress was very reproducible when women were reassessed 55 to 57 months after initial testing. CONCLUSIONS: Laser Doppler flowmetry can quantify the reduced response of irradiated microvasculature to a heat stress. The difference in relative blood flow to a heat stress is greatest in patients < or =6 months post RT, and normalized in patients >36 months post RT.

Late cosmetic results of short fractionation for breast conservation.

BACKGROUND AND PURPOSE: The number of fractions of radiation therapy (RT) used after breast conserving surgery varies widely and accounts for a significant proportion of the workload in a modern radiotherapy department. Internationally, 'standard' therapy ranges from 3 to 7 weeks of daily treatment with or without a boost. Short RT schedules have the attraction of reducing workload but raise concern about an increased risk of late effects and poorer cosmetic outcome. MATERIALS AND METHODS: In a randomized trial, 186 women with T1 or T2, pathologically node-negative breast cancer had cosmetic and various normal tissue effects data collected prospectively. The breast RT prescription was 44 Gy in 16 daily fractions to a tangent pair. RESULTS: Median follow-up is 6.7 years. Actuarial 5-year breast recurrence was 6%. Overall cosmetic results at 5 years were good or excellent in 89% and 96% as reported by physicians and patients, respectively, and were stable between 2 and 5 years. Breast discomfort, erythema, edema and induration were related to both surgery and RT. At 5 years, 20% had breast discomfort, 18% had induration, 6% had erythema and 3% had some degree of breast edema. Fewer patients had these effects at 5 years than immediately after primary surgery. The presence of induration prior to starting RT was associated with a greater likelihood of breast induration 3 or more years following RT (P = 0.02). Thirteen percent of patients, generally those with large breasts, developed mild inframammary telangiectasia by 5 years. CONCLUSIONS: Results are comparable to those reported from centers employing more conventional fractionation. Short fractionation produces acceptable cosmetic results for the majority of women if there are no contraindications to RT and in the absence of significant post-operative breast induration.

Unifying theory of hypoxia tolerance: molecular/metabolic defense and rescue mechanisms for surviving oxygen lack.

We develop a unifying theory of hypoxia tolerance based on information from two cell level models (brain cortical cells and isolated hepatocytes) from the highly anoxia tolerant aquatic turtle and from other more hypoxia sensitive systems. We propose that the response of hypoxia tolerant systems to oxygen lack occurs in two phases (defense and rescue). The first lines of defense against hypoxia include a balanced suppression of ATP-demand and ATP-supply pathways; this regulation stabilizes (adenylates) at new steady-state levels even while ATP turnover rates greatly decline. The ATP demands of ion pumping are down-regulated by generalized "channel" arrest in hepatocytes and by "spike" arrest in neurons. Hypoxic ATP demands of protein synthesis are down-regulated probably by translational arrest. In hypoxia sensitive cells this translational arrest seems irreversible, but hypoxia-tolerant systems activate "rescue" mechanisms if the period of oxygen lack is extended by preferentially regulating the expression of several proteins. In these cells, a cascade of processes underpinning hypoxia rescue and defense begins with an oxygen sensor (a heme protein) and a signal-transduction pathway, which leads to significant gene-based metabolic reprogramming-the rescue process-with maintained down-regulation of energy-demand and energy-supply pathways in metabolism throughout the hypoxic period. This recent work begins to clarify how normoxic maintenance ATP turnover rates can be drastically (10-fold) down-regulated to a new hypometabolic steady state, which is prerequisite for surviving prolonged hypoxia or anoxia. The implications of these developments are extensive in biology and medicine.

Can clonidine, enoximone, and enalaprilat help to protect the myocardium against ischaemia in cardiac surgery?

OBJECTIVE: To evaluate whether clonidine, enoximone, and enalaprilat reduce ischaemia-related myocardial cell damage in cardiac surgery. DESIGN: Prospective randomised controlled trial. SETTING: Clinical investigation in a cardiac anaesthesia department of a university hospital. PATIENTS: 88 consecutive patients undergoing coronary artery bypass surgery. INTERVENTIONS: After induction of anaesthesia patients continuously received the alpha 2 agonist clonidine (group 1, n = 22), the phosphodiesterase (PDE) III inhibitor enoximone (group 2, n = 22), the angiotensin converting enzyme (ACE) inhibitor enalaprilat (group 3, n = 22), or saline solution as placebo (control group, n = 22). The infusion was stopped immediately before the start of cardiopulmonary bypass. MAIN OUTCOME MEASURES: The ST segment was analysed and the activity of creatine kinase isoenzyme MB (CKMB), cardiac troponin T (TnT), and the BB isoenzyme of glycogen phosphorylase (GPBB) were measured before the start of infusion (baseline), after weaning from cardiopulmonary bypass (CPB), at the end of surgery, 5 h after CPB, and on the morning of the first and third postoperative days. RESULTS: Biometric data and time of cross-clamping were not significantly different in the four groups. Changes in the ST segment indicating ischaemia were least common in the enalaprilat group (P < 0.05). Postoperatively, CKMB activity was significantly higher in the clonidine and the control groups. Both new markers of myocardial cell damage increased more after CPB and postoperatively in the control patients (TnT peak: (mean (SD)) 3.99 (0.35) microgram/1; GPBB peak: 82 (15) ng/ml) and the clonidine-treated group (TnT peak: 3.80 (0.3) microgram/1; GPBB peak: 85 (14) ng/ml). Enalaprilat-treated patients showed the smallest overall changes in standard (CKMB) and new serological markers of myocardial ischaemia (TnT peak: 0.71 (0.1) microgram/1; GPBB peak: 44 (14) ng/ml). CONCLUSIONS: In patients treated with enalaprilat before CPB, both new, more sensitive markers of ischaemic myocardial tissue damage increased significantly less than in an untreated control group. Those treated with enoximone also had lower plasma concentration of TnT and GPBB than the control group, whereas clonidine did not reduce the concentration of these markers of myocardial ischaemia. Pharmacological interventions, such as the continuous infusion of the ACE inhibitor enalaprilat, before start of CPB may help to protect the heart against ischaemia/reperfusion injury.