76 research outputs found
Studies using the anti-idiotypic monoclonal antibody 105AD7 in patients with advanced and primary colorectal cancer
Introduction. The anti-idiotypic monoclonal antibody 10SAD7 mimics the tumour associated antigen 791T/ gp72, present on approximately 80% of colorectal cancer cells. A Phase I study using 10SAD7 in 13 patients with advanced colorectal cancer has shown that it is nontoxic, and conferred a survival advantage on patients who received it [Denton GWL 1994].
Aim. There were two aims of this work. The first was to assess whether. the survival advantage seen in the Phase I study was reproducible in a Phase II study. The second was to immunise patients with primary colorectal cancer, in a non-randomised adjuvant study, and explore further the immune responses generated.
Materials and Methods. Patients with advanced colorectal cancer were recruited to a randomised, double-blind, placebo controlled survival study. The first patient was recruited to this Phase II study in April 1994, and the last in October 1996. Four trial centres were used- Nottingham, Hull, Leeds, and Newcastle. Eligible patients had a life expectancy of 3 months, and none had received radiotherapy or chemotherapy in the preceding 1 and 3 months, respectively. Patients attended on 3 occasions, 6 weeks apart, receiving 10µg of 10SAD7/alum i.d. followed by 100µg i.m. Venous blood was assayed for blood count and differential, liver function, urea and electrolytes, and CEA. Chest X-rays and CT scans were performed at trial entry and week 12 where possible. Dates of death were recorded following consultation with General Practitioner or referring clinician.
In addition, patients with primary colorectal cancer were recruited to a non-randomised adjuvant study, whereby they received 10SAD7 before surgery. Venous blood samples were taken between immunisation and operation, and assayed for lymphocyte subsets. Samples taken from resection specimens were analysed immunohistochemically. Fresh tumours were in addition disaggregated, and separated TIL labelled with a panel of monoclonal antibodies, and analysed by flow cytometry. Control tumours were similarly labelled. All analysis was performed blind.
Results. 162 patients were randomised to the Phase II study, between April 1994 and October 1996. 85 received 105AD7 and 77 placebo. The mean ages and sex-ratios of the two groups were comparable, as was the time from diagnosis of advanced disease to trial entry (172v179 days). Median survival from date on study was 124 and 184 days, in 105AD7 and placebo arms, respectively (p=O.38). Survival from date of diagnosis of advanced disease was 456 and 486 days (p=O.82). Chemotherapy and radiotherapy all prolonged survival in a multivariate analysis. Only one serious adverse event was seen in the 105AD7 arm, and this was felt unlikely to be attributable to the vaccine.
Twenty-four patients were recruited to the adjuvant study. Immunohistochemical analysis of tumour sections from 16 patients showed increased infiltration of CD4 and CD8 expressing lymphocytes, relative to a well matched control group (p<O.05). Infiltration of CD4, CD8 and CD56 expressing lymphocytes combined was significantly higher, as was that of the mitochondrial antigen 7A6, expressed on cells undergoing apoptosis (p<O.005). The activation marker CD25 was also significantly increased (p<O.05). Flow cytometric analysis of disaggregated tumours from 16 trial and 22 control patients, confirmed the increased expression of CD25 on TIL in the 105AD7 group (p<O.01). Peripheral blood phenotyping failed to show any significant increase in any lymphocyte subset, following immunisation.
A separate analysis was performed comparing 2 year survival and recurrence in 23 patients immunised by the previous CRC Fellow, with 97 matched controls from the Trent Audit. No significant difference was seen between the two groups.
Discussion. No survival difference was seen between patients receiving l05AD7 and placebo, in the Phase II study. This suggests that any immune responses generated by l05AD7 are insufficient to have a significant effect on tumour growth, in patients with advanced disease. Work has therefore focused on immunising patients with primary colorectal cancer. Patients receiving l05AD7 prior to resection of their primary tumours, showed an increased number of activated lymphocytes, and apoptosis, at the tumour site, relative to a well-matched control group. The numbers in the survival analysis based on patients recruited by the previous CRC fellow, are insufficient to show whether any of these immunological changes confer a survival advantage. This question can only be answered in a large, prospective, placebo-controlled study in patients with primary colorectal cancer
Studies using the anti-idiotypic monoclonal antibody 105AD7 in patients with advanced and primary colorectal cancer
Introduction. The anti-idiotypic monoclonal antibody 10SAD7 mimics the tumour associated antigen 791T/ gp72, present on approximately 80% of colorectal cancer cells. A Phase I study using 10SAD7 in 13 patients with advanced colorectal cancer has shown that it is nontoxic, and conferred a survival advantage on patients who received it [Denton GWL 1994].
Aim. There were two aims of this work. The first was to assess whether. the survival advantage seen in the Phase I study was reproducible in a Phase II study. The second was to immunise patients with primary colorectal cancer, in a non-randomised adjuvant study, and explore further the immune responses generated.
Materials and Methods. Patients with advanced colorectal cancer were recruited to a randomised, double-blind, placebo controlled survival study. The first patient was recruited to this Phase II study in April 1994, and the last in October 1996. Four trial centres were used- Nottingham, Hull, Leeds, and Newcastle. Eligible patients had a life expectancy of 3 months, and none had received radiotherapy or chemotherapy in the preceding 1 and 3 months, respectively. Patients attended on 3 occasions, 6 weeks apart, receiving 10µg of 10SAD7/alum i.d. followed by 100µg i.m. Venous blood was assayed for blood count and differential, liver function, urea and electrolytes, and CEA. Chest X-rays and CT scans were performed at trial entry and week 12 where possible. Dates of death were recorded following consultation with General Practitioner or referring clinician.
In addition, patients with primary colorectal cancer were recruited to a non-randomised adjuvant study, whereby they received 10SAD7 before surgery. Venous blood samples were taken between immunisation and operation, and assayed for lymphocyte subsets. Samples taken from resection specimens were analysed immunohistochemically. Fresh tumours were in addition disaggregated, and separated TIL labelled with a panel of monoclonal antibodies, and analysed by flow cytometry. Control tumours were similarly labelled. All analysis was performed blind.
Results. 162 patients were randomised to the Phase II study, between April 1994 and October 1996. 85 received 105AD7 and 77 placebo. The mean ages and sex-ratios of the two groups were comparable, as was the time from diagnosis of advanced disease to trial entry (172v179 days). Median survival from date on study was 124 and 184 days, in 105AD7 and placebo arms, respectively (p=O.38). Survival from date of diagnosis of advanced disease was 456 and 486 days (p=O.82). Chemotherapy and radiotherapy all prolonged survival in a multivariate analysis. Only one serious adverse event was seen in the 105AD7 arm, and this was felt unlikely to be attributable to the vaccine.
Twenty-four patients were recruited to the adjuvant study. Immunohistochemical analysis of tumour sections from 16 patients showed increased infiltration of CD4 and CD8 expressing lymphocytes, relative to a well matched control group (p<O.05). Infiltration of CD4, CD8 and CD56 expressing lymphocytes combined was significantly higher, as was that of the mitochondrial antigen 7A6, expressed on cells undergoing apoptosis (p<O.005). The activation marker CD25 was also significantly increased (p<O.05). Flow cytometric analysis of disaggregated tumours from 16 trial and 22 control patients, confirmed the increased expression of CD25 on TIL in the 105AD7 group (p<O.01). Peripheral blood phenotyping failed to show any significant increase in any lymphocyte subset, following immunisation.
A separate analysis was performed comparing 2 year survival and recurrence in 23 patients immunised by the previous CRC Fellow, with 97 matched controls from the Trent Audit. No significant difference was seen between the two groups.
Discussion. No survival difference was seen between patients receiving l05AD7 and placebo, in the Phase II study. This suggests that any immune responses generated by l05AD7 are insufficient to have a significant effect on tumour growth, in patients with advanced disease. Work has therefore focused on immunising patients with primary colorectal cancer. Patients receiving l05AD7 prior to resection of their primary tumours, showed an increased number of activated lymphocytes, and apoptosis, at the tumour site, relative to a well-matched control group. The numbers in the survival analysis based on patients recruited by the previous CRC fellow, are insufficient to show whether any of these immunological changes confer a survival advantage. This question can only be answered in a large, prospective, placebo-controlled study in patients with primary colorectal cancer
Can an eye tracker be used as a marker of surgical progress?
Can an eye tracker be used as a marker of surgical progress
Visual search behaviour during laparoscopic cadaveric procedures
Laparoscopic surgery provides a very complex example of medical image interpretation. The task entails: visually
examining a display that portrays the laparoscopic procedure from a varying viewpoint; eye-hand co-ordination; complex
3D interpretation of the 2D display imagery; efficient and safe usage of appropriate surgical tools, as well as other
factors. Training in laparoscopic surgery typically entails practice using surgical simulators. Another approach is to use
cadavers. Viewing previously recorded laparoscopic operations is also a viable additional approach and to examine this
a study was undertaken to determine what differences exist between where surgeons look during actual operations and
where they look when simply viewing the same pre-recorded operations. It was hypothesised that there would be
differences related to the different experimental conditions; however the relative nature of such differences was
unknown. The visual search behaviour of two experienced surgeons was recorded as they performed three types of
laparoscopic operations on a cadaver. The operations were also digitally recorded. Subsequently they viewed the
recording of their operations, again whilst their eye movements were monitored. Differences were found in various eye
movement parameters when the two surgeons performed the operations and where they looked when they simply
watched the recordings of the operations. It is argued that this reflects the different perceptual motor skills pertinent to
the different situations. The relevance of this for surgical training is explored
Laparoscopic surgical skills training: an investigation of the potential of using surgeons' visual search behaviour as a performance indicator
Laparoscopic surgery is a difficult perceptual-motor task and effective and efficient training in the technique is
important. Viewing previously recorded laparoscopic operations is a possible available training technique for surgeons
to increase their knowledge of such minimal access surgery (MAS). It is not well known whether this is a useful
technique, how effective it is or what effect it has on the surgeon watching the recorded video. As part of an on-going
series of studies into laparoscopic surgery, an experiment was conducted to examine whether surgical skill level has an
effect on the visual search behaviour of individuals of different surgical experience when they examine such imagery.
Medically naive observers, medical students, junior surgeons and experienced surgeons viewed a laparoscopic recording
of a recent operation. Initial examination of the recorded eye movement data indicated commonalities between all
observers, largely irrespective of surgical experience. This, it is argued, is due to visual search in this situation largely
being driven by the dynamic nature of the images. The data were then examined in terms of surgical steps and also in
terms of interventions when differences were found related to surgical experience. Consequently, it is argued that
monitoring the eye movements of trainee surgeons whilst they watch pre-recorded operations is a potential useful adjunct
to existing training regimes
Development of a telehealth monitoring service after colorectal surgery: a feasibility study
AIM: To evaluate the feasibility of a text-messaging system to remotely monitor and support patients after discharge following elective colorectal surgery, within an enhanced recovery protocol.
METHODS: Florence (FLO) is a National Health Service telehealth solution utilised for monitoring chronic health conditions, such as hypertension, using text-messaging. New algorithms were designed to monitor the well-being, basic physiological observations and any patient-reported symptoms, and provide support messages to patients undergoing colorectal surgery within an enhanced recovery after surgery protocol for 30 d after discharge. All interactions with FLO and physiological readings were recorded and patients were invited to provide feedback.
RESULTS: Over a four-week period, 16 out of 17 patients used the FLO telehealth service at home. These patients did not receive telephone follow-up at three days, as per our standard protocol, unless they reported being unwell or did not make use of the technology. Three patients were readmitted within 30 d, and two of these were identified as being unwell by FLO prior to readmission. No adverse events attributable to the use of the technology were encountered.
CONCLUSION:The utilisation of telehealth in the early follow-up of patients who have undergone major colorectal surgery after discharge is feasible. The use of this technology may assist in the early recognition and management of complications after discharge
Effect of public reporting of surgeons' outcomes on patient selection, "gaming," and mortality in colorectal cancer surgery in England: population based cohort study.
OBJECTIVE: To determine the effect of surgeon specific outcome reporting in colorectal cancer surgery on risk averse clinical practice, "gaming" of clinical data, and 90 day postoperative mortality. DESIGN: National cohort study. SETTING: English National Health Service hospital trusts. POPULATION: 111 431 patients diagnosed as having colorectal cancer from 1 April 2011 to 31 March 2015 included in the National Bowel Cancer Audit. INTERVENTION: Public reporting of surgeon specific 90 day mortality in elective colorectal cancer surgery in England introduced in June 2013. MAIN OUTCOME MEASURES: Proportion of patients with colorectal cancer who had an elective major resection, predicted 90 day mortality based on characteristics of patients and tumours, and observed 90 day mortality adjusted for differences in characteristics of patients and tumours, comparing patients who had surgery between April 2011 and June 2013 and between July 2013 and March 2015. RESULTS: The proportion of patients with colorectal cancer undergoing major resection did not change after the introduction of surgeon specific public outcome reporting (39 792/62 854 (63.3%) before versus 30 706/48 577 (63.2%) after; P=0.8). The proportion of these major resections categorised as elective or scheduled also did not change (33 638/39 792 (84.5%) before versus 25 905/30 706 (84.4%) after; P=0.5). The predicted 90 day mortality remained the same (2.7% v 2.7%; P=0.3), but the observed 90 day mortality fell (952/33 638 (2.8%) v 552/25 905 (2.1%)). Change point analysis showed that this reduction was over and above the existing downward trend in mortality before the introduction of public outcome reporting (P=0.03). CONCLUSIONS: This study did not find evidence that the introduction of public reporting of surgeon specific 90 day postoperative mortality in elective colorectal cancer surgery has led to risk averse clinical practice behaviour or "gaming" of data. However, its introduction coincided with a significant reduction in 90 day mortality
Laparoscopic Colorectal Surgery Outcomes Improved After National Training Program (LAPCO) for Specialists in England
OBJECTIVE: To examine the impact of The National Training Programme for Laparoscopic Colorectal Surgery (Lapco) on the rate of laparoscopic surgery and clinical outcomes of cases performed by Lapco surgeons after completion of training.SUMMERY BACKGROUND DATA: Lapco provided competency-based supervised clinical training for specialist colorectal surgeons in England.METHODS: We compared the rate of laparoscopic surgery, mortality and morbidity for colorectal cancer resections by Lapco delegates and non-Lapco surgeons in 3-year periods preceding and following Lapco using difference in differences analysis. The changes in the rate of post-Lapco laparoscopic surgery with the Lapco sign-off competency assessment and in-training global assessment scores were examined using risk-adjusted cumulative sum to determine their predictive clinical validity with predefined competent scores of 3 and 5 respectively.RESULTS: 108 Lapco delegates performed 4586 elective colorectal resections pre-Lapco and 5115 post-Lapco while non-Lapco surgeons performed 72930 matched cases. Lapco delegates had a 37.8% increase in laparoscopic surgery which was greater than non-Lapco surgeons by 20.9% (95% CI, 18.5 to 23.3, p [less than] 0.001) with a relative decrease in 30-day mortality by -1.6% (95% CI, -3.4 to -0.2, p = 0.039) and 90-day mortality by -2.3% (95% CI, -4.3 to -0.4, p = 0.018). The change point of risk-adjusted cumulative sum was 3.12 for competency assessment tool and 4.74 for global assessment score whereas laparoscopic rate increased from 44% to 66% and 40% to 56% respectively.CONCLUSIONS: Lapco increased the rate of laparoscopic colorectal cancer surgery and reduced mortality and morbidity in England. In-training competency assessment tools predicted clinical performance after training
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