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Brent W Miedema

Publications and source records attributed to Brent W Miedema.

7 recordsLinked to original sources
PubMed2006

Analysis of micrometastatic disease in sentinel lymph nodes from resectable colon cancer: results of Cancer and Leukemia Group B Trial 80001.

PURPOSE: To determine whether sentinel lymph node (LN) sampling (SLNS) could reduce the number of nodes required to characterize micrometastatic disease (MMD) in patients with potentially curable colon cancer. PATIENTS AND METHODS: Cancer and Leukemia Group B 80001 was a study to determine whether SLNS could identify a subset of LNs that predicted the status of the nodal basin for resectable colon cancer and, therefore, could be extensively evaluated for the presence of micrometastases. Patients enrolled onto this study underwent SLNS after injection of 1% isosulfan blue, and both sentinel nodes (SNs) and non-SNs obtained during primary tumor resection were sectioned at multiple levels and stained using anti-carcinoembryonic antigen and anticytokeratin antibodies. RESULTS: Using standard histopathology, SNs failed to predict the presence of nodal disease in 13 (54%) of 24 node-positive patients. Immunostains were performed for patients whose LNs were negative by standard histopathology. Depending on the immunohistochemical criteria used to assign LN positivity, SN examination resulted in either an unacceptably high false-positive rate (20%) or a low sensitivity for detection of MMD (40%). CONCLUSION: By examining both SNs and non-SNs, this multi-institutional study showed that SNs did not accurately predict the presence of either conventionally defined nodal metastases or MMD. As a result, SLNS is not a useful technique for the study of MMD in patients with colon cancer.

Biomarkers, Tumor↗
PubMed2006

Laparoscopic resection of colon cancer and synchronous liver metastasis.

The recommended surgical approach to synchronous colorectal metastasis has not been clarified. Simultaneous open liver and colon resection for synchronous colorectal carcinoma has been shown beneficial when compared to staged resections. A review of the literature has shown the benefits of both laparoscopic colon resection for colorectal cancer and laparoscopic left lateral segmentectomy in liver disease. We present the case of a 60-year-old male with sigmoid colon carcinoma and a synchronous solitary liver metastasis localized to the left lateral segment. Using laparoscopic techniques, we were able to achieve simultaneous resection of the sigmoid colon and left lateral liver segment.

Colonic Neoplasms↗
PubMed2003

Methods for decreasing postoperative gut dysmotility.

Postoperative disturbances of gastrointestinal function (postoperative ileus) are among the most significant side-effects of abdominal surgery for cancer. Without specific treatment, major abdominal surgery causes a predictable gastrointestinal dysfunction which endures for 4-5 days and results in an average hospital stay of 7-8 days. Ileus occurs because of initially absent and subsequently abnormal motor function of the stomach, small bowel, and colon. This disruption results in delayed transit of gastrointestinal content, intolerance of food, and gas retention. The aetiology of ileus is multifactorial, and includes autonomic neural dysfunction, inflammatory mediators, narcotics, gastrointestinal hormone disruptions, and anaesthetics. In the past, treatment has consisted of nasogastric suction, intravenous fluids, correction of electrolyte abnormalities, and observation. Currently, the most effective treatment is a multimodal approach. Median stays of 2-3 days after removal of all or part of the colon (colectomy) are now achievable. Recent discoveries have the potential to significantly reduce postoperative ileus in patients with cancer who have had abdominal surgery.

Abdomen↗
PubMed2002

Small bowel motility and transit after aortic surgery.

OBJECTIVE: The inability to tolerate feedings after aortic surgery prolongs hospitalization. The aim of this study was to define jejunal manometric and small bowel transit characteristics associated with the ileus that follows transperitoneal aortic surgery. METHODS: Five male patients who underwent transperitoneal infrarenal aortobifemoral bypass had intraoperative placement of a jejunal multilumen catheter. The open abdomen allowed precise placement of pressure recording ports at 20, 22, 24, 26, 28, and 38 cm past the ligament of Treitz. Three-hour manometric studies were done after surgery and for 3 postoperative days. The migrating motor complex was identified visually on the manometric tracings, and pressure waves were identified with computer and a motility index calculated. Motility data were compared with healthy control data previously reported in the literature. Small bowel transit was determined with barium and serial abdominal radiographs. RESULTS: All patients had ileus develop with return of bowel sounds at 2 to 7 days (median, 6 days) and flatus at 3 to 9 days (median, 7 days) after surgery. Jejunal motor activity was present within 6 hours of surgery, but the motility index was less in patients then in control subjects. The postoperative migrating motor complexes differed from control subjects in having more phase I, less phase II, and more frequent phase IIIs. Phase III retrograde migration was common in the patients but not in the control subjects. Small bowel transit was 2 days or greater in all patients. CONCLUSION: Motor activity is present in the jejunum shortly after aortic surgery. However, the activity is decreased in intensity and the fasting cycle differs from control subjects. Retrograde migration of phase III is the most likely abnormality, resulting in delayed small bowel transit. The data would predict a high rate of enteral feeding intolerance early after surgery. Future studies should focus on pharmacologic manipulation to rapidly return small bowel motility to a more normal state after aortic surgery.

Aged↗