Long-course preoperative chemoradiation versus 5 × 5 Gy and consolidation chemotherapy for clinical T4 and fixed clinical T3 rectal cancer: long-term results of the randomized Polish II study.

BACKGROUND: This trial evaluated whether preoperative short-course radiotherapy and consolidation chemotherapy (CCT) were superior to chemoradiation in rectal cancers with clinical (c)T4 or fixed cT3. Previously, we reported early results showing no differences in the radical surgery rate (primary end point). In the short-course/CCT group, we observed lower acute toxicity of preoperative treatment and better overall survival (OS). We updated results to determine whether the benefit in OS was sustained and to evaluate late complications. PATIENTS AND METHODS: Patients with cT4 or fixed cT3 rectal cancer were randomized either to preoperative 5 × 5 Gy and three cycles of FOLFOX4 or to chemoradiation (50.4 Gy with bolus 5-Fu, leucovorin and oxaliplatin). RESULTS: Patients (N = 515) were eligible for analysis, 261 in the short-course/CCT group and 254 in the chemoradiation group. The median follow-up was 7.0 years. The difference in OS was insignificant [hazard ratio (HR) 0.90; 95% confidence interval (CI) 0.70-1.15; P = 0.38). However, the difference in early OS favouring short-course/CCT previously reported was observed again, being 9% at 3 years (95% CI 0.5% to 17%). This difference disappeared later; at 8 years OS was 49% in both groups. There was no difference in disease-free survival (HR 0.95; 95% CI 0.75-1.19; P = 0.65) at 8 years 43% versus 41% in the short-course/CCT group versus the chemoradiation group, respectively. The corresponding values for cumulative incidences of local failure and distant metastases did not differ and were HR = 1.08, 95% CI 0.70-1.23, P = 0.60, 35% versus 32% and HR = 1.10, 95% CI 0.68-1.23, P = 0.54, 36% versus 34%, respectively. The rate of late complications was similar (P = 0.66), grade 3+ being 11% versus 9% in the short-course/CCT group versus the chemoradiation group, respectively. CONCLUSION: The superiority of preoperative short-course/CCT over chemoradiation was not demonstrated. CLINICAL TRIAL NUMBER: The trial is registered as ClinicalTrials.gov number NCT00833131.

Impact of pelvic bone marrow irradiation on the hematological toxicity of subsequent chemotherapy in rectal cancer.

Preoperative radio(chemo)therapy in rectal cancer may irreversibly damage pelvic bone marrow (PBM) and impair the tolerance of subsequent chemotherapy. The aim of the study was to assess the relationship between the irradiated volume of PBM and the toxicity of subsequent 5-fluorouracil, oxaliplatin, leucovorin (FOLFOX-4) in rectal cancer. We included consecutive rectal cancer patients who received FOLFOX-4 postoperatively or due to cancer relapse. The PBM was divided into iliac (IM), lumbosacral (LSM), and lower pelvic (LPM) marrow. We assessed mean dose, and percentage of volume receiving 10%-90% (V10%-V90%) of the prescribed dose for PBM, IM, LSM, and LPM. Generalized linear model for repeated measures (GLM) was used to test an influence of dose-volumes distribution on toxicities grade 2 or higher (TOX2) and grade 3 or higher (TOX3). The two-sided t-test was used to evaluate the difference in mean dose, mean V20%, and mean V40% between patients who experienced TOX2 or TOX3 and those who did not. 39 patients met eligibility criteria. Because of the low occurrence of TOX3 (n=3), related analyses were abandoned. We found no influence of dose-volume distribution on TOX2 in GLM and no significant differences in mean dose, mean V20%, and mean V40% for PBM, IBM, LSM, and LPM between patients who experienced TOX2 and those who did not. To conclude, no relationship between doses received by PBM in preoperative radio(chemo)therapy in rectal cancer and hematological tolerance of subsequent FOLFOX-4 chemotherapy was found.

Does the addition of oxaliplatin to preoperative chemoradiation benefit cT4 or fixed cT3 rectal cancer treatment? A subgroup analysis from a prospective study.

BACKGROUND: Whether there is any benefit derived from adding oxaliplatin to fluoropyrimidine-based preoperative chemoradiation is currently unknown in cases of advanced cT3 or cT4 tumours. Our aim was to evaluate this issue by analysing a randomized trial, which compared two schedules of preoperative treatment (chemoradiation vs. 5 × 5 Gy with 3 cycles of consolidation chemotherapy) for cT4 or fixed cT3 rectal cancer. PATIENTS AND METHODS: Delivery of oxaliplatin was mandatory to the first part of the study. For the second part, its delivery in both treatment-assigned groups was left to the discretion of the local investigator. We analysed a subgroup of 272 patients (136 in the oxaliplatin group and 136 in the fluorouracil-only group) from institutions that had omitted oxaliplatin in the second part of the study. RESULTS: Circumferential resection margin negative (CRM-) status rate was 68% in the oxaliplatin group and 70% in the fluorouracil-only group, p = 0.72. The pathological complete response rate (pCR) was correspondingly 14% vs. 7%, p = 0.10. Following multivariable analysis, when comparing the CRM- status in the oxaliplatin group to the fluorouracil-only group, the odds ratio was 0.79 (95 CI 0.35-1.74), p = 0.54; there being no interaction between concomitant chemoradiation and 5 × 5 Gy with consolidation chemotherapy; pinteraction = 0.073. For pCR, the corresponding results were 0.47 (95 CI 0.19-1.16), p = 0.10, pinteraction = 0.84. CONCLUSION: No benefit was found of adding oxaliplatin in terms of CRM nor pCR rates for either concomitant or sequential settings in preoperative radiochemotherapy for very advanced rectal cancer.

Dual-role FilmArray® diagnostics for high-impact viral diseases.

In this study, we explored the potential utility of the human-focused FilmArray® Respiratory Panel for the diagnosis of a broad range of influenza viruses of veterinary concern as compared with the standard portfolio of recommended TaqMan®-based diagnostic tests. In addition, we discuss some potential operational advantages associated with the use of such integrated sample extraction, amplification and analysis devices in the context of a future long-term, dual-role strategy for the detection of emergency diseases of both human and veterinary concern.

Long-course oxaliplatin-based preoperative chemoradiation versus 5 × 5 Gy and consolidation chemotherapy for cT4 or fixed cT3 rectal cancer: results of a randomized phase III study.

BACKGROUND: Improvements in local control are required when using preoperative chemoradiation for cT4 or advanced cT3 rectal cancer. There is therefore a need to explore more effective schedules. PATIENTS AND METHODS: Patients with fixed cT3 or cT4 cancer were randomized either to 5 × 5 Gy and three cycles of FOLFOX4 (group A) or to 50.4 Gy in 28 fractions combined with two 5-day cycles of bolus 5-Fu 325 mg/m(2)/day and leucovorin 20 mg/m(2)/day during the first and fifth week of irradiation along with five infusions of oxaliplatin 50 mg/m(2) once weekly (group B). The protocol was amended in 2012 to allow oxaliplatin to be then foregone in both groups. RESULTS: Of 541 entered patients, 515 were eligible for analysis; 261 in group A and 254 in group B. Preoperative treatment acute toxicity was lower in group A than group B, P = 0.006; any toxicity being, respectively, 75% versus 83%, grade III-IV 23% versus 21% and toxic deaths 1% versus 3%. R0 resection rates (primary end point) and pathological complete response rates in groups A and B were, respectively, 77% versus 71%, P = 0.07, and 16% versus 12%, P = 0.17. The median follow-up was 35 months. At 3 years, the rates of overall survival and disease-free survival in groups A and B were, respectively, 73% versus 65%, P = 0.046, and 53% versus 52%, P = 0.85, together with the cumulative incidence of local failure and distant metastases being, respectively, 22% versus 21%, P = 0.82, and 30% versus 27%, P = 0.26. Postoperative and late complications rates in group A and group B were, respectively, 29% versus 25%, P = 0.18, and 20% versus 22%, P = 0.54. CONCLUSIONS: No differences were observed in local efficacy between 5 × 5 Gy with consolidation chemotherapy and long-course chemoradiation. Nevertheless, an improved overall survival and lower acute toxicity favours the 5 × 5 Gy schedule with consolidation chemotherapy. CLINICAL TRIAL NUMBER: The trial is registered as ClinicalTrials.gov number NCT00833131.

Postoperative chemotherapy in patients with rectal cancer receiving preoperative radio(chemo)therapy: A meta-analysis of randomized trials comparing surgery ± a fluoropyrimidine and surgery + a fluoropyrimidine ± oxaliplatin.

BACKGROUND: There is no consensus on the role of postoperative chemotherapy in patients with rectal cancer who have received preoperative radio(chemo)therapy. MATERIALS AND METHODS: A systematic review and meta-analysis were performed of trials that used preoperative radio(chemo)therapy and randomized patients either between postoperative chemotherapy and observation or between a fluoropyrimidine only (FU-only) and a fluoropyrimidine with oxaliplatin (FU-OXA) as postoperative chemotherapy. RESULTS: Five randomized studies compared postoperative chemotherapy with observation in a total of 2398 patients. None of these trials demonstrated a statistically significant benefit of chemotherapy for OS and DFS. The pooled differences in OS and DFS did not differ statistically significantly between the chemotherapy group and the observation group. The hazard ratios (HRs) and 95% confidence intervals (CIs) were 0.95 (CI: 0.82-1.10), P = 0.49 and 0.92 (CI: 0.80-1.04), P = 0.19, respectively. In the subgroup of trials in which randomization was performed after surgery (n = 753), a statistically significant positive pooled chemotherapy effect was observed for DFS (HR = 0.79, 95% CI: 0.62-1.00, P = 0.047), but not for OS (P = 0.39). Four randomized trials compared adjuvant FU-OXA with adjuvant FU-only in 2710 patients. In two trials, the difference in DFS between groups was statistically significant in favour of FU-OXA, and in the other two trials, the difference was not significant. The pooled difference in DFS between the FU-OXA group and the FU-only group was not statistically significant: HR = 0.84 (CI: 0.66-1.06), P = 0.15. CONCLUSION: The use of postoperative chemotherapy in patients with rectal cancer receiving preoperative radio(chemo)therapy is not based on strong scientific evidence.

Topoisomerase 2α status in invasive breast carcinoma - comparison of its clinical value according to immunohistochemical and fluorescence in situ hybridization methods of evaluation.

The main purpose of the study was to compare topoisomerase 2α (TOP2A) status in invasive breast carcinomas to the outcome of a therapy containing neoadjuvant treatment with anthracyclines (a combination chemotherapy treatment for breast cancer, namely AC [cyclophosphamide, doxorubicin]). To achieve these goals we created a method of evaluation with criteria based on two methods used in the present study (immunohistochemical [IHC] and fluorescence in situ hybridization [FISH]). The threshold for positive immunohistochemically evaluated status was set for all cases with: nuclear stain intensity score 3+ in 10% or more nuclei and nuclear stain intensity score 2+ in 50% or more nuclei. Our results suggest that TOP2A status may be used as a predictive factor for patient selection for protocols which include anthracyclines as one of the chemotherapeutics. Both methods, IHC and FISH, are suitable for implementation for diagnostic purposes, but IHC positive status measured according to the criteria presented above is the best predictor of longer disease-free survival (DFS) according to our study. Immunohistochemical also gave satisfactory results in all analyzed cases in comparison to only 60% of cases analyzed by FISH.

Palliative radiotherapy and chemotherapy instead of surgery in symptomatic rectal cancer with synchronous unresectable metastases: a phase II study.

BACKGROUND: In stage IV rectal cancer, palliative surgery is often carried out upfront. This study investigated whether the surgery can be avoided. PATIENTS AND METHODS: Forty patients with symptomatic primary rectal adenocarcinoma and synchronous distant metastases deemed to be unresectable received 5 × 5 Gy irradiation and then oxaliplatin-based chemotherapy. Before treatment, 38% of patients had a near-obstructing lesion. The palliative effect was evaluated by questionnaires completed by the patients. RESULTS: The median follow-up for living patients was 26 months (range 19-34). The median overall survival was 11.5 months. Eight patients (20%) required surgery during the course of their disease: seven patients required stoma creation and one had local excision. Thirty percent of patients had a complete resolution of pelvic symptoms during the whole course of the disease, and 35% had significant improvement. In the subgroup with a near-obstructing lesion, 23% of patients required stoma creation. In all patients, the probability of requiring palliative surgery at 2 years was 17.5% [95% confidence interval (CI) 13% to 22%), and the probability of sustained good palliative effect after radiotherapy and chemotherapy was 67% (95% CI 58% to 76%). CONCLUSION: Short-course radiotherapy and chemotherapy allowed most patients to avoid surgery, even those with a near-obstructing lesion. CLINICALTRIALS: The trial is registered with ClinicalTrials.gov: number NCT01157806.

Altering the therapeutic paradigm towards a distal bowel margin of < 1 cm in patients with low-lying rectal cancer: a systematic review and commentary.

AIM: The 1-cm rule of distal bowel clearance in patients with low-lying rectal cancer undergoing anterior resection is based mainly on pathological data showing distal intramural spread. Because clinical data are contradictory, a review that includes only cancers located ≤ 5 or ≤ 6 cm from the anal verge was carried out. METHOD: A systematic review of the literature identified seven studies that presented results in relation to a margin of ≤ 1 cm (n = 293) vs > 1 cm (n = 315). In six studies, pre- or postoperative radiotherapy was implemented, and in one study patients were treated with surgery alone. Three studies, all implementing radiotherapy, reported results related to a margin of ≤ 5 mm (n = 51) vs > 5 mm (n = 125). RESULTS: In none of the studies were the differences in local recurrence rate between the small and large margin groups statistically significant. The pooled analysis of six studies, in which patients received perioperative radiotherapy, showed a 1.2% [95% confidence interval (Cl) -4.5-7.0%] higher local recurrence rate in the ≤ 1 cm margin group compared with the > 1 cm margin group (P = 0.6). The corresponding figures for the ≤ 5 mm cut-off point were 0.5% (95% CI -7.6-8.7%, P = 0.9). The 5-year local recurrence rate in the only study in which radiotherapy had not been used was 8.6% higher in the ≤ 1 cm margin group compared with the > 1 cm margin group (P = 0.09). CONCLUSION: Clinical evidence does not support the 1-cm rule in patients with low-lying rectal cancer undergoing pre- or postoperative radiotherapy.

Detection and measurement of carbohydrate deficient transferrin in serum using immuno-capture mass spectrometry: diagnostic applications for annual ryegrass toxicity and corynetoxin exposure.

The neurological livestock disease annual ryegrass toxicity (ARGT) is caused by the ingestion of the naturally occurring glycolipid toxins - the corynetoxins. Corynetoxins also threaten human health as potential contaminants of the food supply. Presently, there are no routine diagnostic tests for corynetoxins-exposure in humans or livestock. Chronic ingestion of corynetoxins has been modeled in rats exposed to dietary tunicamycins for 12 months and carbohydrate deficient transferrin (CDT) has been previously identified as a candidate disease biomarker. Here, the technique of immuno-capture mass spectrometry (icMS) was used to evaluate serum levels of CDT, discriminating between control and tunicamycins-exposed rats with 85% accuracy. The icMS approach is based on the combination of specific transferrin enrichment with functionalized magnetic beads and automated matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). With no other clinically-relevant diagnostic tests available icMS could be readily adapted for high-throughput clinical assessment of corynetoxins-exposure in humans or livestock.

Peptides specific for Mycobacterium avium subspecies paratuberculosis infection: diagnostic potential.

Mycobacterium avium subspecies paratuberculosis (Map) is the causative agent of Johne's disease (JD). Current serological diagnostic tests for JD are limited by their sensitivity when used in sub-clinical stages of the disease. Our objective was to identify peptides that mimic diagnostically important Map epitopes that might be incorporated into a new-generation JD diagnostic. Four peptides were isolated from a phage-displayed random peptide library by screening on antibodies derived from Map-infected goats. The peptides were recognised by antibodies from Map-infected goats but not by antibodies from uninfected goats. The peptides elicited immune responses in rabbits, which reacted strongly with bona fide Map antigens proving the peptides were true epitope mimics. To assess the diagnostic value a panel of goat sera was screened for reactivity's with peptides. The peptides were recognised by antibodies from a proportion of goats infected with Map compared with control animals with a diagnostic specificity of 100% and the sensitivity ranged from 50 to 75%. Combinations of any two peptides improved sensitivity 62.5-87.5% and 100% sensitivity was achieved with three of the four peptides in combination. These data suggest peptides representing diagnostically important Map epitopes could be incorporated into a sensitive diagnostic test.

A long-term bacteriological and immunological study in Holstein-Friesian cattle experimentally infected with Mycobacterium avium subsp. paratuberculosis and necropsy culture results for Holstein-Friesian cattle, Merino sheep and Angora goats.

The aims were to longitudinally evaluate the interferon-gamma (IFN-gamma) test in comparison to faecal culture and the absorbed ELISA in a cattle infection model for Johne's disease and to determine the adult infection status, by necropsy and tissue culture, of sheep, goats and cattle infected as young animals. Clinical disease, faecal culture results and immunological responses for Merino sheep [Stewart, D.J., Vaughan, J.A., Stiles, P.L., Noske, P.J., Tizard, M.L.V., Prowse, S.J., Michalski, W.P., Butler, K.L., Jones, S.L., 2004. A long-term study in Merino sheep experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies. Vet. Microbiol. 104, 165-178] and Angora goats [Stewart, D.J., Vaughan, J.A., Stiles, P.L., Noske, P.J., Tizard, M.L.V., Prowse, S.J., Michalski, W.P., Butler, K.L., Jones, S.L., 2006. A long-term study in Angora goats experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies. Vet. Microbiol. 113, 13-24], in the same experiments as the Holstein-Friesian cattle, have been described. Two longitudinal experiments involving Holstein-Friesian cattle challenged with either bovine or ovine strains of Mycobacterium avium subsp. paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the IFN-gamma test and the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Cell-mediated (CMI) responses were substantially higher for the bovine Map strain during the 42-month period following dosing but then declined in the remaining 12 months. However, for the ovine Map challenge and control groups, CMI responses were not significantly different from each other. None of the cattle developed clinical disease and only one of the cattle in the bovine Map gut mucosal tissue challenged group was a persistent faecal shedder and also an ELISA antibody responder which developed after shedding commenced. Culture of tissues, following necropsy at the completion of the experiments, showed no evidence of infection in any of the challenged cattle and sheep for either the bovine or ovine Map strain in contrast to positive cultures for challenged goats in the same experiments. The tissues from the control cattle, sheep and goats were culture negative. The cattle were less susceptible to the bovine and ovine Map strains than goats and sheep with the goats being the least naturally resistant.

Comparison of the effects of acylation and amidation on the antimicrobial and antiviral properties of lactoferrin.

AIMS: To compare amidation and acylation of lactoferrin (LF) from bovine milk, as a means of enhancing its antimicrobial and antiviral properties. METHODS AND RESULTS: LF was chemically modified by amidation with a 1-ethyl-3-[3-(dimethylamino) propyl] carbodiimide (EDC) in the presence of ammonium ions or by acylation with either succinic or acetic anhydride. In the test systems used, amidation substantially enhanced the activity of LF against Pseudomonas fluorescens in comparison with native LF. However, increasing the net negative charge of LF by acylation had no effect on the activity of LF against P. fluorescens, and abrogated the antimicrobial activity of LF against Bacillus subtilis and Saccharomyces cerevisiae. Increasing the net negative charges of LF by acylation eliminated its antimicrobial and antiviral effects against poliovirus and feline calicivirus (nonenveloped viruses). CONCLUSIONS: The addition of positive charges to LF via amidation enhanced antimicrobial properties in contrast to increasing the negative charges by acylation, which abolished both the antimicrobial and antiviral properties of LF. SIGNIFICANCE AND IMPACT OF THE STUDY: The effects of charge alteration of LF determined in this study provides a basis for further development of LF formulations with enhanced antimicrobial effectiveness for use in food process hygiene, veterinary and health-care applications.

Long-term results of a randomized trial comparing preoperative short-course radiotherapy with preoperative conventionally fractionated chemoradiation for rectal cancer.

BACKGROUND: Neoadjuvant chemoradiotherapy does not alter anal sphincter preservation or postoperative complications compared with short-course radiotherapy alone in patients with clinical stage T3 or T4 resectable rectal cancer. The aim of this study was to compare survival, local control and late toxicity in the two treatment groups. METHODS: The study randomized 312 patients to receive either preoperative irradiation (25 Gy in five fractions of 5 Gy) and surgery within 7 days or chemoradiation (50.4 Gy in 28 fractions of 1.8 Gy, bolus 5-fluorouracil and leucovorin) and surgery 4-6 weeks later. The median follow-up of living patients was 48 (range 31-69) months. RESULTS: Early radiation toxicity was higher in the chemoradiation group (18.2 versus 3.2 per cent; P < 0.001). The actuarial 4-year overall survival was 67.2 per cent in the short-course group and 66.2 per cent in the chemoradiation group (P = 0.960). Disease-free survival was 58.4 versus 55.6 per cent (P = 0.820), crude incidence of local recurrence was 9.0 versus 14.2 per cent (P = 0.170) and severe late toxicity was 10.1 versus 7.1 per cent (P = 0.360) respectively. CONCLUSION: Neoadjuvant chemoradiation did not increase survival, local control or late toxicity compared with short-course radiotherapy alone.

A long-term study in Angora goats experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies.

Two longitudinal experiments involving Angora goats challenged with either bovine or ovine strains of Mycobacterium avium subspecies paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the interferon-gamma (IFN-gamma) test and the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Persistent shedding, IFN-gamma production, seroconversion and clinical disease occurred earlier with the bovine Map gut mucosal tissue challenge inoculum than with cultured bacteria. The IFN-gamma responses of the gut mucosal tissue and bacterial challenge groups were substantially and consistently higher than those of the control group. The in vivo and cultured cattle strains were much more pathogenic for goats than the sheep strains with persistent faecal shedding, seroconversion and clinical disease occurring in the majority of bovine Map challenged goats. With the ovine Map, 3 goats developed persistent antibody responses but only one of these goats developed persistent faecal shedding and clinical disease. However, there was no significant difference between the IFN-gamma responses of the tissue challenged, bacterial challenged and control groups. Compared with sheep, the ELISA appeared to have higher sensitivity and the IFN-gamma test lower specificity.

Clinical significance of serum cytokine measurements in untreated colorectal cancer patients: soluble tumor necrosis factor receptor type I--an independent prognostic factor.

The aim of this study was to exploit the potential clinical use of circulating cytokine measurements in colorectal cancer (CRC) patients. The levels of cytokines and cytokine receptors were assessed by ELISA in the sera of 50 healthy volunteers and 157 patients with previously untreated CRC and then related to clinicopathological features and prognosis. All tumors were verified histologically as colorectal adenocarcinomas and staged according to TNM classification. The levels of circulating interleukin (IL)-6, IL-8, macrophage colony-stimulating factor (M-CSF) and interleukin 1 receptor antagonist (IL-1ra) significantly increased with the clinical stage of CRC, and the levels of IL-6, soluble tumor necrosis factor (sTNF) receptor type I (RI), soluble interleukin 2 receptor alpha and TNFalpha with tumor grade, while IL-6, IL-8, M-CSF, IL-1ra and sTNF RI levels significantly rose with bowel wall invasion. None of the cytokine or soluble cytokine receptor levels were influenced by age, gender and colon versus rectum localization. sTNF RI, IL-8, IL-6 and vascular endothelial growth factor measurements demonstrated the highest diagnostic sensitivity. sTNF RI was found elevated in the greatest percentage of all CRC patients, in the greatest proportion of stage I patients and presented the best diagnostic sensitivity. In addition, the sTNF RI level strongly correlated with tumor grade and invasion and proved to be an independent prognostic factor.

Development of a Johne's disease infection model in laboratory rabbits following oral administration of Mycobacterium avium subspecies paratuberculosis.

To assess the rabbit as a model for the study of Johne's disease pathogenesis, a breeding group of adult and juvenile New Zealand white rabbits were orally challenged with three doses of the Mycobacterium avium subspecies paratuberculosis wildtype bovine strain, CLIJ623, on three occasions. Faecal culture, post-mortem tissue bacteriological culture and histopathology were used to monitor the disease progression in the rabbits for more than 2 years. Of 4 adult and 16 juvenile orally dosed rabbits M. paratuberculosis organisms were recovered bacteriologically from two and three animals, respectively, using the BACTECtrade mark radiometric culture system. Tissue sites from which the bacteria were recovered included the mesenteric lymph nodes, ileocaecal valve, vermiform appendix, caecum, proximal colon and jejunum. Body weight loss, reduced abdominal fat and mild lesions were observed at necropsy in four infected rabbits. Diarrhoea and persistent faecal shedding of bacteria were not observed. Faecal culture did not yield any cultivable mycobacterial organisms on solid media.

A long-term study in Merino sheep experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies.

Two longitudinal experiments involving Merino sheep challenged with either bovine or ovine strains of Mycobacterium avium subsp. paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the interferon-gamma test, the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Infections were induced with either a bovine or ovine strain of Map in separate experiments with infections being more easily established, in terms of faecal bacterial shedding and clinical disease when the challenge inoculum was prepared from gut mucosal tissue than cultured bacteria. The patterns of response for shedding and clinical disease were similar. Cell-mediated immune responses were proportionally elevated by at least an order of magnitude in all sheep dosed with either a bovine or ovine strain of Map. Conversely, antibody responses were only elevated in a relatively small proportion of infected sheep. Neither of the clinically affected tissue challenged sheep developed an antibody response despite the presence of persistent shedding and the development and decline in cell-mediated immunity. The results indicated that for sheep the interferon-gamma test may be useful for determining if a flock has been exposed to ovine Johne's disease.

Sphincter preservation following preoperative radiotherapy for rectal cancer: report of a randomised trial comparing short-term radiotherapy vs. conventionally fractionated radiochemotherapy.

BACKGROUND AND PURPOSE: The aim was to verify whether preoperative conventionally fractionated chemoradiation offers an advantage in sphincter preservation in comparison with preoperative short-term irradiation. PATIENTS AND METHODS: Patients with resectable T3-4 rectal carcinoma without sphincters' infiltration and with a lesion accessible to digital rectal examination were randomised into: preoperative 5x5Gy short-term irradiation with subsequent total mesorectal excision (TME) performed within 7 days or chemoradiation to a total dose of 50.4Gy (1.8Gy per fraction) concomitantly with two courses of bolus 5-fluorouracil and leucovorin followed by TME after 4-6 weeks. Surgeons were obliged to base the type of operation on the tumour status at the time of surgery. RESULTS: Between 1999 and 2002, 316 patients from 19 institutions were enrolled. The sphincter preservation rate was 61% in the 5x5Gy arm and 58% in the radiochemotherapy arm, P = 0.57. The tumour was on average 1.9 cm smaller (P < 0.001) among patients treated with chemoradiation compared with short-term schedule. For patients who underwent sphincter-preserving procedure, the surgeons generally followed the rule of tailoring the resection according to tumour downsizing; the median distal bowel margin was identical (2 cm) for both randomised groups. However, in the chemoradiation group, five patients underwent abdominoperineal resection despite clinical complete response. CONCLUSIONS: Despite significant downsizing, chemoradiation did not result in increased sphincter preservation rate in comparison with short-term preoperative radiotherapy. The surgeons' decisions were subjective and based on pre-treatment tumour volume at least in clinical complete responders.