Biomedical subjects

J R T Monson

Publications and source records attributed to J R T Monson.

16 recordsLinked to original sources

PubMed2006

Transanal endoscopic microsurgery for carcinoma of the rectum.

BACKGROUND: The authors present their experience with rectal cancers managed by transanal endoscopic microsurgery (TEM). METHODS: This prospective study investigated patients undergoing primary TEM excision for definitive treatment of rectal cancer between January 1996 and December 2003 by a single surgeon in a tertiary referral colorectal surgical unit. RESULTS: For this study, 52 patients (30 men and 22 women) underwent TEM excision of a rectal cancer. Their mean age was 74.3 years (range, 48-93 years). The median diameter of the lesions was 3.44 cm (range, 1.6-8.5 cm). The median distance of the lesions from the anal verge was 8.8 cm (range, 3-15 cm), with the tumor more than 10 cm from the anal verge in 36 patients. The median operating time was 90 min (range, 20-150 min), and the median postoperative stay was 2 days. All patients underwent full-thickness excisions. There were 11 minor complications, 2 major complications, and no deaths. The mean follow-up period was 40 months (range, 22-82 months). None of the pT1 rectal cancers received adjuvant therapy. Eight patients with pT2 rectal cancer and two patients with pT3 rectal cancer received postoperative adjuvant therapy. The overall local rate of recurrence was 14%, and involved cases of T2 and T3 lesions, with no recurrence after excision of T1 cancers. Three patients died during the follow-up period, but no cancer-specific deaths occurred. CONCLUSIONS: The findings warrant the conclusion that TEM is a safe, effective treatment for selected cases of rectal cancer, with low morbidity and no mortality. The TEM procedure broadens the range of lesions suitable for local resection to include early cancers (pTis and pT1) and more advanced cancers only in frail people.

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PubMed2006

Do supervised colorectal trainees differ from consultants in terms of quality of TME surgery?

OBJECTIVE: The quality of surgical excision is held to be a major determinant of outcome following surgery for rectal cancer. Macroscopic examination of the excised mesorectum allows for reproducible assessment of the quality of surgery. We aimed to determine whether quality of excision undertaken by colorectal trainees under supervision was comparable with that performed by consultants, as measured using mesorectal grades. METHOD: A total of 130 consecutive patients undergoing potentially curative resection for primary adenocarcinoma of the rectum in our centre from 2001 to 2003 were included in the study. The pathologists graded the excised mesorectum according to staged classification proposed by Quirke. The outcome (quality of mesorectal excision and secondary outcomes including local recurrence and overall recurrence) of operations performed by consultants was compared with that of trainees. Statistical significance was tested using Pearson chi(2) test. RESULTS: Eighty-nine operations were performed by consultants and 41 by senior colorectal trainees with consultant supervision. Forty-four patients (49%) had good mesorectum when operated by consultants in comparison with 17 (41.5%) by the trainees. There was no statistically significant difference (P = 0.717) between the two groups in terms of quality of mesorectum excised after potentially curative resection. Furthermore, there were seven local recurrences in patients operated by consultants (7.8%) when compared with four in the trainee group (9.5%) and once again there was no statistical significance between the two groups (P = 0.719). CONCLUSION: We conclude that the quality of rectal cancer excision, as defined by mesorectal grades, achieved by supervised colorectal trainees is comparable with that achieved by consultants.

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PubMed2005

Primary carcinoma of the appendix - Hull series.

BACKGROUND: Appendiceal carcinoma (AC) is a rare entity that does not have a well-defined treatment strategy. At presentation, most patients are clinically thought to have appendicitis and the diagnosis is made only by formal histology. Once the diagnosis of AC is made, patients are treated by various strategies including surgery, chemotherapy depending on nodal status of the disease. AIM: To review the Hull hospitals' experience with AC. METHODS: Between 1982 and 2002, 10 patients with primary AC were seen. The histopathology reports of all appendiceal specimens removed were traced. Follow-up was by chart review or patient follow-up as appropriate. We did not include patients with primary carcinoid tumours or secondary adenocarcinoma. RESULTS: There was an equal sex distribution. All patients underwent surgery, 3 had post-operative chemotherapy. Complete follow-up information was available with a median follow-up time of 56 months, with a range of 12-168 months. Five patients survived at least 4 years from the time of diagnosis. CONCLUSION: Long-term survival in patients with AC is possible.

Adenocarcinoma, Mucinous↗

PubMed2005

Is local excision of T2/T3 rectal cancers adequate?

In selected patients, local excision of rectal cancer may be an alternative to radical surgery such as abdominoperineal excision of the rectum or anterior resection. Local excision carries lower mortality and morbidity, without the functional disturbance or alteration in body image that can be associated with radical surgery. There are several techniques of local therapy for rectal cancer, with most experience being available in transanal excision. Transanal endoscopic microsurgery is also used but experience with this newer technique is limited. Patient selection is the most important factor in successful local excision; however, specific criteria for selecting patients have not been universally accepted. Review of the published literature is difficult because of the variation in adjuvant therapy regimes and follow-up strategies, as well as results reported in terms of local recurrence and survival rates. There is increasing evidence to suggest that local excision should be restricted to patients with T1-stage rectal cancer without high-risk factors. The place for local excision in patients with T2 or high-risk T1 tumours requires prospective, randomised multicentre trials comparing radical surgery with local excision, with or without adjuvant therapy. Local excision for T3 tumours should be restricted to the palliative setting or patients unfit for radical surgery.

Colorectal Neoplasms↗

PubMed2005

The long term survival of rectal cancer patients following abdominoperineal and anterior resection: results of a population-based observational study.

AIMS: The surgical management of rectal cancer is not uniform. Both abdominoperineal (APR) and anterior resection (AR) are used in potentially curative surgery but there is no definitive evidence regarding comparative survival outcomes and no randomised controlled trials. We sought to determine if any differences in survival existed between patients who received AR or APR. In addition, we sought to determine how variations in surgical management relate to the degree of specialisation and caseload of the managing consultant. PATIENTS AND METHODS: A retrospective study of population-based data collected by the Northern and Yorkshire Cancer Registry and Information Service was undertaken. All patients (3521) diagnosed with rectal cancer in the former Yorkshire Regional Health Authority (population 3.6 million) between 1986 and 1994 who received either an APR or AR were included. Survival was assessed in relation to the surgical methods adopted. In addition, we determined whether the extent of specialisation of the managing consultant influenced the type of operation adopted. RESULTS: A Log Rank test, stratified for sex and age, showed a statistically significant 6.7% 5-year survival advantage for patients receiving AR (p=0.0064). AR was more likely to be performed by more specialist colorectal cancer surgeons (p<0.001). CONCLUSIONS: This evidence suggests that the outcomes of the two main surgical procedures used in curative surgery for rectal cancer are different and that, when possible, AR should be the operation of choice. Our results show no indication of excess risk associated with this procedure compared with APR.

Aged↗

PubMed2005

Laparoscopic resection of colorectal cancer.

Laparoscopic surgery has revolutionised procedures such as cholecystectomy since its inception in the 1980s. After initial enthusiasm with laparoscopic colorectal resections in the early 1990s, resection of colorectal malignancy was largely abandoned outside clinical trials because of reports of inferior oncological outcomes including local and port-site recurrence. More recently, however, an increasing number of reports have demonstrated that laparoscopic surgery for colorectal cancer though technically demanding is feasible, and the results of large multi-centred randomised trials showing oncological equivalence are becoming available. Technological advances in laparoscopic equipment along with the increasing skills and experience of laparoscopic surgeons have extended the indications and reduced the contraindications for laparoscopic colectomy. This, along with the use of fast- track protocols is changing the way we manage patients. The future of laparoscopic colorectal surgery is assured, driven not only by the physical benefits to the patient in the short and medium term, the reduced financial burden on in-patient stay, and post-operative return to work, but also increasing patient demand. This in turn requires that surgeons should ensure high quality training and operative competence to maintain the high standards achieved by the pioneers in this field.

Colorectal Neoplasms↗

PubMed2004

Percutaneous radiofrequency ablation of colorectal hepatic metastases - initial experience. An adjunct technique to systemic chemotherapy for those with inoperable colorectal hepatic metastases.

BACKGROUND AND AIM: Most patients with hepatic metastases from colorectal carcinoma are unsuitable for resection. Radiofrequency ablation (RFA) has been applied to such lesions at laparotomy. This study aimed to evaluate the less invasive approach of percutaneous RFA. METHOD: Patients with unresectable liver metastases identified on cross-sectional imaging were considered for percutaneous RFA either alone or in combination with systemic chemotherapy. Subjects with >6 lesions or lesions of maximum size >70 mm were excluded. Percutaneous RFA was applied under sedation and radiological guidance (CT/US). Treatment effect was determined by follow-up imaging. Actuarial survival was calculated by the Kaplan-Meier analysis. RESULTS: Thirty patients (21 males), median age 74.5 years (range 44-85 years), underwent percutaneous RFA to 56 lesions during 54 treatment sessions. The median size of lesion was 30 mm (range 8-70 mm). Fifteen lesions were treated more than once because of recurrence or incomplete ablation. The median ablation time per lesion was 12 min (range 4.5-36 min). Eleven patients had pre-procedural chemotherapy and 15 patients received chemotherapy after treatment. There was minimal associated morbidity (5.6% of treatments). Median hospital stay per treatment was 1 day (range 1-7). Median actuarial survival from the date of first percutaneous RFA was 22 months (95% CI 12.9-31.1 months). Eleven patients were alive at the time of data collection. CONCLUSION: Percutaneous RFA is a safe, well-tolerated intervention for unresectable hepatic metastases which can be repeated, if required. The technique may be associated with prolonged survival in this selected group of subjects. Future studies should consider the role of percutaneous RFA either in place of or as an adjunct to palliative chemotherapy.

Adult↗

PubMed2004

Evaluation of quality of life after laparoscopic surgery: evidence-based guidelines of the European Association for Endoscopic Surgery.

BACKGROUND: Measuring health-related quality of life (QoL) after surgery is essential for decision making by patients, surgeons, and payers. The aim of this consensus conference was twofold. First, it was to determine for which diseases endoscopic surgery results in better postoperative QoL than open surgery. Second, it was to recommend QoL instruments for clinical research. METHODS: An expert panel selected 12 conditions in which QoL and endoscopic surgery are important. For each condition, studies comparing endoscopic and open surgery in terms of QoL were identified. The expert panel reached consensus on the relative benefits of endoscopic surgery and recommended generic and disease-specific QoL instruments for use in clinical research. RESULTS: Randomized trials indicate that QoL improves earlier after endoscopic than open surgery for gastroesophageal reflux disease (GERD), cholecystolithiasis, colorectal cancer, inguinal hernia, obesity (gastric bypass), and uterine disorders that require hysterectomy. For spleen, prostate, malignant kidney, benign colorectal, and benign non-GERD esophageal diseases, evidence from nonrandomized trials supports the use of laparoscopic surgery. However, many studies failed to collect long-term results, used nonvalidated questionnaires, or measured QoL components only incompletely. The following QoL instruments can be recommended: for benign esophageal and gallbladder disease, the GIQLI or the QOLRAD together with SF-36 or the PGWB; for obesity surgery, the IWQOL-Lite with the SF-36; for colorectal cancer, the FACT-C or the EORTC QLQ-C30/CR38; for inguinal and renal surgery, the VAS for pain with the SF-36 (or the EORTC QLQ-C30 in case of malignancy); and after hysterectomy, the SF-36 together with an evaluation of urinary and sexual function. CONCLUSIONS: Laparoscopic surgery provides better postoperative QoL in many clinical situations. Researchers would improve the quality of future studies by using validated QoL instruments such as those recommended here.

Cholecystectomy, Laparoscopic↗

PubMed2004

Artificial intelligence in medicine.

INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of different artificial intelligent techniques is presented in this paper along with the review of important clinical applications. RESULTS: The proficiency of artificial intelligent techniques has been explored in almost every field of medicine. Artificial neural network was the most commonly used analytical tool whilst other artificial intelligent techniques such as fuzzy expert systems, evolutionary computation and hybrid intelligent systems have all been used in different clinical settings. DISCUSSION: Artificial intelligence techniques have the potential to be applied in almost every field of medicine. There is need for further clinical trials which are appropriately designed before these emergent techniques find application in the real clinical setting.

Artificial Intelligence↗

PubMed2003

Extrarenal retroperitoneal angiomyolipoma: management of a rare benign tumour.

BACKGROUND: Extrarenal retroperitoneal angiomyolipomas are benign tumours of mesenchymal tissue origin. The diagnosis of these tumours is usually based on the perioperative findings and confirmed by the resultant specimen's histology. The main differential diagnosis is liposarcoma, and accurate preoperative imaging combined with fine-needle aspiration cytology may permit a non-operative approach to these tumours. CASE PRESENTATION: We describe a single case of extrarenal retroperitoneal pelvic angiomyolipoma and provide the first case of magnetic resonance imaging of these extremely rare tumours. CONCLUSION: This article discusses the presentation, management, and outcome associated with these tumours.

Angiomyolipoma↗

PubMed2003

Vascular endothelial growth factor and soluble Tie-2 receptor in colorectal cancer: associations with disease recurrence.

AIMS: A delicate balance exists between pro-angiogenic factors and anti-angiogenic factors to regulate the process of angiogenesis. To investigate the relationship of VEGF-A with other angiogenic factors and to determine their clinical usefulness. METHODS: Venous blood was obtained from 47 patients with CRC prior to curative resections. VEGF-A, sVEGFR-1, sTie-2 receptor, and TNF-alpha levels in serum were measured concurrently with quantitative ELISA. The median follow-up term for patients without cancer death was 29 months (range 20-35). RESULTS: Both serum TNF-alpha activity and sVEGFR-1 was detectable in 17% and 74% of CRC patients, respectively. Univariate analysis demonstrated that the disease free survival was significantly associated with the tumour location (P=0.031), T category (P=0.006), TNF-alpha activity (P=0.0008), sTie-2 receptor (P=0.012) and VEGF-A (P<0.00001). From the survival analysis, a higher serum VEGF-A and sTie-2 receptor level is associated with an earlier development of metastases. Using multivariate Cox's regression analysis, the only independent predictors of outcome were sTie-2 receptor (P=0.038) and VEGF-A (P=0.006). CONCLUSIONS: sTie-2 receptor and VEGF-A appear to associate independently with the development of metastases, with VEGF-A being the most powerful predictor of outcome. These data also suggest that measurement of pre-operative sTie-2 receptor and VEGF-A is superior to determining VEGF-A alone with regards to predictive value.

Aged↗

PubMed2003

Transanal endoscopic microsurgery: a viable operative alternative in selected patients with rectal lesions.

BACKGROUND: Local excision of rectal lesions is being increasingly undertaken, especially in those unfit for major surgery. The traditional transanal approach is often cumbersome and limited to low and mid rectal lesions. Transanal endoscopic microsurgery (TEMS) is being used to excise both benign and malignant rectal lesions, including those in the upper rectum. METHODS: Prospective analysis of all patients undergoing a TEMS excision between January 1997 and December 2000 in a specialized colorectal unit. RESULTS: Forty patients underwent a TEMS resection, with a mean age of 72 years (SD, 10 years). The mean distance of the lesions from the anal verge was 9.8 cm (SD, 3.1 cm). In 24 patients, the lesion was located >or=10 cm from the anal verge, making them unsuitable for traditional transanal resection. The mean operative time was 91 minutes (SD, 34 minutes), and the mean postoperative stay was 3 days (SD, 1.5 days). No mortality was associated with the procedure, and there was minimal morbidity in 15%. There has been no recurrence in the 18 patients who had a malignant lesion excised. CONCLUSIONS: The TEMS operating system provides the surgeon with a suitable alternative for the resection of benign and malignant rectal neoplasms in selected patients. It has the advantage of providing visual clarity of the operative field, allowing more precise dissection and a minimally invasive approach to mid and upper rectal lesions. There has been no mortality and minimal morbidity. We advocate its inclusion as part of a colorectal surgeon's operative armamentarium for these selected cases.

Aged↗

PubMed2003

Isolation and characterisation of vascular endothelial growth factor-165 specific scFv fragments by phage display.

Vascular endothelial growth factor (VEGF) is a multifunctional cytokine which plays a major role in angiogenesis. Alternative splicing causes the production of several different isoforms (VEGF-A 121, 145, 165, 189, 206). VEGF is essential for tumor angiogenesis and several studies have correlated elevated VEGF levels with tumor stage, metastases and progression. Antibody phage display was employed to isolate two scFv antibody fragments, D8 and F10, with specificity for the VEGF165 isoform. It was shown by ELISA and competitive immunohistochemistry that each clone bound to VEGF165 but not VEGF121. Immunohistochemistry with D8 and F10 on colorectal carcinoma and adenoma sections revealed positive staining similar to that shown by a polyclonal VEGF antibody. The scFv antibody fragments, D8 and F10, will be useful in specifically detecting circulating VEGF165 in cancer patients as most studies to date have quantified the total level of circulating VEGF (121 and 165). These reagents will allow further elucidation of the role of VEGF in tumor angiogenesis.

Adenoma↗

PubMed2002

The role of laparoscopy in the multimodality treatment of colorectal cancer.

Ten years after the first reports of laparoscopic techniques in colorectal surgery the precise role for these approaches in future colorectal practice as still to be defined. However, it seems most unlikely that the application is going to disappear. Laparoscopic colectomy is undoubtedly a complex. time-consuming procedure and it is clear that the technique is intolerant of difficult cases and will likely remain thus. Therefore. the potential advantages of laparoscopy do not as yet appear to be attainable across the board in colorectal resection. Such generalized advantage may, however, be tantalizingly close. Although many studies have failed to show major benefits for laparoscopy in terms of postoperative recovery, it must be remembered that most of these have been of insufficient statistical power to settle the issue. What is clear to all involved in the field is that very many patients do gain major benefit from the minimally invasive approach. The challenge for the future lies in developing the technology to such a point that these benefits for patients are more reproducible. The requirement for a significant abdominal incision to deliver an intact specimen represents a significant hurdle in this regard. The importance of pathological staging for colorectal cancer at present mandates retrieval of an intact specimen. It is of course possible that radiological staging may develop to such a point that surgeons need only remove the lesion with minimal attention to lymphadenectomy. Alternatively, new adjuvant therapies may arrive that, by virtue of increased efficacy and low side-effect profiles, may be applicable to all but the earliest lesions. Finally, increasing health awareness and application of screening programs may lead to a preponderance of large polyps and preinvasive lesions for which a more limited resection may be appropriate. Obviously these scenarios remain almost entirely speculative. However, the trend towards less invasive local therapy for colorectal cancer seems inexorable, and we firmly believe that laparoscopy will come to play an increasing role. Finally, we suggest that the oncological safety of laparoscopy is of less concern than was the case some years ago. The specter of port-site metastasis, once so alarming, has faded. It is now apparent from all of the larger scale studies that port-site metastases are not a significant issue in the presence of adequate training and laparoscopic skills. Almost without exception, the accumulating evidence seems to point to equivalence in terms of disease-specific recurrence and survival between patients treated using conventional and laparoscopic techniques. We foresee these findings being confirmed by the North American and European trials.

Colectomy↗

PubMed2002

Karyotypic variation between independently cultured strains of the cell line MCF-7 identified by multicolour fluorescence in situ hybridization.

The breast cancer cell line MCF-7 is a widely used model in breast cancer research however a number of conflicting reports have been published regarding its biological properties. We hypothesised that there will be significant in vitro mutation and genotypic evolution over time in this cell line. To assess the genetic divergence of MCF-7 at the chromosomal level, we analysed MCF-7 cell lines grown independently at three different laboratories using M-FISH and CGH. In addition, MCF-7 cells from our own laboratory were also analysed at two time points 18 months apart. Several common chromosomal translocations were identified in all variants of the cell lines. In addition, a significant number of unique abnormalities were identified, characterising each of the variants studied. Genotypic differences between cell lines grown independently in different laboratories would significantly alter the phenotypic characteristics of each cell line rendering biological properties inconsistent between laboratories.

Breast Neoplasms↗

PubMedDate not supplied

Giant colonic diverticulum.

BACKGROUND: Over 100 giant colonic diverticuli have been recorded in the literature to date. The magnetic resonance imaging (MRI) and pathophysiology of their aetiology have rarely been described. AIM: To report a giant colonic diverticulum along with the MRI of this clinical entity. RESULTS: An 87 year old female presented with symptoms of tenesmus, urgency and alteration in bowel habit. A type I giant colonic diverticulum was diagnosed and a segmental colonic surgical resection was performed. The plain abdominal radiograph, barium enema and MRI, along with classification and management options are presented. CONCLUSION: Giant colonic diverticuli are rare surgical curiosities that may be successfully treated with either primary segmental or extended colonic resection.

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