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J M D Wheeler

Publications and source records attributed to J M D Wheeler.

10 recordsLinked to original sources
PubMed2005

Long-term function after restorative proctocolectomy.

PURPOSE: Early functional outcome after restorative proctocolectomy and formation of an ileoanal pouch is known to be good, but there are minimal data on the long-term function of the pouch. The aim of this study was to look at the long-term functional outcome in patients who had undergone restorative proctocolectomy and formation of an ileoanal pouch. METHODS: A total of 151 consecutive patients (96 males, 55 females) who underwent ileoanal pouch surgery between April 1983 and May 1993 were identified. Functional outcomes from the previous 12 months were appraised by a standardized questionnaire. RESULTS: The median age at surgery was 31 years (range, 6-63 years), with a median follow-up of 142 months (range, 100-221 months). Eighteen patients have had their pouches excised, with another patient being defunctioned. Therefore 19 patients (13 percent) had suffered pouch failure. Altogether, 115 patients were available for follow-up, and 98 patients (85 percent) returned questionnaires. The median pouch-emptying frequency was five times (range, 1-17) during the day and one time (range, 0-6) at night. A total of 74 percent of patients had perfect continence during the day. Most of the patients had no life-style restrictions related to the pouch, and 98 percent of patients would recommend a pouch to others. CONCLUSIONS: Long-term functional outcome after ileoanal pouch surgery is good in most patients. For patients requiring proctocolectomy, ileoanal pouch surgery can now be recommended as an excellent long-term option.

Adolescent↗
PubMed2005

Epigenetics, mismatch repair genes and colorectal cancer.

The recent discovery of hypermethylation of the promoter of genes is a powerful epigenetic mechanism for the inactivation of tumour suppressor genes in colorectal and other cancers. Approximately 95% of hereditary non-polyposis colorectal cancers (HNPCCs) and 15% of sporadic colorectal cancers (CRCs) are replication error positive (RER(+)). Although DNA mutations are found in mismatch repair genes in the majority of HNPCC CRC, mutations are rare in sporadic RER(+) CRCs. We have shown that the principal cause of an RER(+) phenotype is hypermethylation of the promoter of hMLH1, resulting in the absence of hMLH1 protein. In contrast to sporadic RER(+) CRCs, we found that hypermethylation of hMLH1 does not occur in HNPCC CRC, suggesting the possibility of further differences between the two types of RER(+) tumours in the adenoma to carcinoma pathway. Other known tumour suppressor genes with few or no mutations may be candidates for epigenetic changes. One such gene is E-cadherin, and we described the first mutations of this gene in CRCs. Half of all CRCs were found to be hypermethylated in the Ecadherin promoter and this correlated with reduced E-cadherin expression. Epigenetic changes occur in CRCs and arise in different frequencies in separate genes. Hypermethylation of the promoter may be reversed and gene function restored to a cell, thus partially undoing the cancer phenotype.

Adaptor Proteins, Signal Transducing↗
PubMed2004

Preoperative chemoradiotherapy and total mesorectal excision surgery for locally advanced rectal cancer: correlation with rectal cancer regression grade.

PURPOSE: Preoperative long-course chemoradiotherapy is recommended for rectal carcinoma when there is concern that surgery alone may not be curative. Downstaging of the tumor can be measured as rectal cancer regression grade (1-3) and may be of importance when estimating the prognosis. The aim of this study was to look at the long-term results of tumor regression in patients receiving long-course chemotherapy before surgical resection of rectal cancer. METHODS: We reviewed those patients who received preoperative chemoradiotherapy followed by surgical resection for carcinoma of the mid rectum or distal rectum found to be stage T3/4 between January 1995 and November 1999. Patients received 45 to 50 Gy irradiation in 2-Gy fractions and an infusion of 5-fluorouracil. Surgical specimens were assessed for rectal cancer regression grade. Patients were followed up routinely with clinical examination, computed tomography, and colonoscopy. RESULTS: Sixty-five patients with a mean age 65 (range, 32-83) years underwent chemoradiotherapy before surgical resection. Thirty patients (46 percent) were classified as rectal cancer regression Grade 1, with 9 patients (14 percent) having complete sterilization of the tumor. Fifty-three patients (82 percent) underwent a curative resection. Overall survival, with a median follow-up of 39 (range, 24-83) months, was 67 percent and was associated with tumor downstaging. The local recurrence rate was 5.8 percent in those patients who underwent a curative resection and was significantly lower with rectal cancer regression Grade 1 tumors (P = 0.03). Eight of nine patients (89 percent) whose tumor had been sterilized were alive and well with no recurrence of tumor at a median follow-up of 41 (range, 24-70) months. CONCLUSIONS: Preoperative chemoradiotherapy resulted in significant regression of tumor. Overall survival was high and was associated with downstaging of tumor. The local recurrence rate was significantly lower with rectal cancer regression Grade 1 tumors and was not seen in patients with sterilized tumors.

Adenocarcinoma↗
PubMed2003

The incidence and causes of permanent stoma after anterior resection.

AIMS: Defunctioning stomas are used following anterior resection to guard against the serious consequences of anastomotic leak such as pelvic sepsis and generalized peritonitis. This study aims to determine what proportion of patients undergoing anterior resection have a defunctioning stoma, how many of these patients do not have their stoma closed, and the reasons for this. METHODS: All patients undergoing a resection for rectal cancer in our institution in a five year period (January 1995 to December 1999) are included in the study. Anterior resection was performed on 154 patients, divided into 76 anterior resections (AR) and 78 low anterior resections (defined as the anastomosis within 6 cm of the anal verge). The data from these patients were analysed retrospectively. RESULTS: Of the total of 154 patients undergoing anterior resection, 59 (38%) were defunctioned, divided into 33 with loop ileostomy and 26 with loop colostomy. Five of these patients had not had their stoma closed at a median follow up of four years (range 1.5-6.5 years). The reasons for non closure were anastomotic stricture (2), metastatic disease (2), and patient choice (1). When comparing AR and LAR, 16% of patients had a defunctioning stoma after AR, compared with 60% after LAR (P < 0.01). CONCLUSION: Anterior resection is being performed for very low rectal tumours in order to avoid a permanent stoma. However we have found that 8% of patients who are defunctioned with a stoma at anterior resection will not have their stoma closed, and conclude that patients should be warned of this pre-operatively.

Aged↗
PubMed2002

Quantification of histologic regression of rectal cancer after irradiation: a proposal for a modified staging system.

PURPOSE: Long-course preoperative radiotherapy has been recommended for rectal carcinoma when there is concern about the ability to perform a curative resection, for example, in larger tethered tumors or those sited anteriorly or near the anal sphincter. "Downstaging" of the tumor may occur, and this is of importance when estimating the prognosis and selecting postoperative therapy for patients. We studied the effects of preoperative chemoradiotherapy on the pathology of rectal cancer, and we propose a simplified measurement of tumor regression, the Rectal Cancer Regression Grade. METHODS: We have reviewed those patients who received preoperative chemoradiotherapy followed by surgical resection for carcinomas of the mid or distal third of the rectum found to be Stage T3/4 on transrectal ultrasound or CT between January 1995 and December 1998. Patients received 45 to 50 Gy irradiation and an infusion of 5-fluorouracil. The surgical specimens were examined by one pathologist, and the Rectal Cancer Regression Grade was quantified. RESULTS: Forty-two patients, mean age 60 (range, 42-86) years, underwent chemoradiotherapy before surgery for rectal carcinoma. There were 28 anterior resections (67 percent; 9 with a colonic pouch), 12 abdominoperineal resections (27 percent), and 2 Hartmann's procedures (5 percent). Comparison of preoperative and pathologic staging revealed that the depth of invasion was downstaged in 17 patients (38 percent), and the status of involved lymph nodes was downstaged in 13 (50 percent) of 26 patients. Tumor regression was more than 50 percent (Rectal Cancer Regression Grades 1 and 2) in 36 patients (86 percent), with 7 patients (17 percent) having complete regression with absence of residual cancer cells. CONCLUSION: Significant tumor regression was seen in 86 percent of cases after chemoradiotherapy, with 19 patients showing a "good" responsiveness. We propose a modified pathologic staging system for irradiated rectal cancer, the Rectal Cancer Regression Grade, which includes a measurement of tumor regression. The utility of the proposed Rectal Cancer Regression Grade must be tested against long-term outcomes before its value in predicting prognosis and survival can be determined.

Adult↗
PubMed2002

Left retroperitoneal approach for aortic surgery.

Twenty-eight consecutive patients underwent surgery of the abdominal aorta by the left retroperitoneal approach. There were 11 suprarenal, 12 juxtarenal, three complicated infrarenal aneurysms and two occlusive aortoiliac disease (considered to be at high risk) undergoing surgical repair. Twenty-one underwent a tube graft repair whilst seven had a bifurcation graft. There were five deaths in this series; four of which occurred in the initial 12 patients. In our initial experience using the left retroperitoneal approach the overall mortality rate was 17%, though this reduced to 6% for the latter half of the study. The retroperitoneal approach allows access to the supracoeliac aorta without the need for thoracotomy and this approach should be considered for all aortoiliac reconstructive surgery. The transabdominal route to the abdominal aorta remains the most commonly used approach. However, the left retroperitoneal approach offers advantages in high-risk patients and suprarenal and juxtarenal abdominal aortic aneurysms (AAA). This is our initial experience of 28 patients undergoing surgical repair of the abdominal aorta via the left retroperitoneal approach.

Aged↗
PubMed2002

An insight into the genetic pathway of adenocarcinoma of the small intestine.

BACKGROUND: Although the adenoma to carcinoma pathway in colorectal cancer is well described, the mechanisms of carcinogenesis in the small intestine remain unclear. AIMS: The aim of this study was to investigate candidate genes in the genetic pathway of adenocarcinoma of the small intestine. SUBJECTS AND METHODS: A total of 21 non-familial, non-ampullary adenocarcinomas of the small intestine were analysed. DNA was extracted from formalin fixed paraffin wax embedded tissue using standard techniques. The replication error (RER) status was determined by amplification of BAT26. The mutation cluster region (MCR) of the adenomatous polyposis coli (APC) gene was screened using polymerase chain reaction single strand conformational polymorphism and direct sequencing. Immunohistochemistry was performed on formalin fixed paraffin wax embedded tissue using monoclonal antibodies for hMLH1, hMSH2, beta-catenin, E-cadherin, and p53. RESULTS: Fourteen male and seven female patients with a median age of 64 years (range 21-85) presented with adenocarcinoma of the duodenum (10), jejunum (7), and ileum (4). One cancer (5%) was found to be RER+, and all tumours stained positive for hMLH1 and hMSH2. No mutations were detected in the MCR of the APC gene. beta-Catenin showed increased nuclear expression with loss of membranous staining in 10 cancers (48%). Absent or decreased membrane expression of E-cadherin was found in eight cancers (38%). Strong staining of p53 was found in the nucleus of five cancers (24%). CONCLUSION: We did not detect mutations in the MCR of the APC gene, and this suggests that adenocarcinoma of the small intestine may follow a different genetic pathway to colorectal cancer. Abnormal expression of E-cadherin and beta-catenin was common and reflects an early alternative to APC in this pathway in which mutations may be found in adenocarcinoma of the small intestine.

Adaptor Proteins, Signal Transducing↗