Biomedical subjects

R S Stubbs

Publications and source records attributed to R S Stubbs.

40 records · Page 3Linked to original sources

PubMedDate not supplied

Selective internal radiation therapy with 90yttrium microspheres for extensive colorectal liver metastases.

Increasing attention has been given to treatments for colorectal liver metastases ever since hepatic resection was established as being worthwhile. Given the high proportion of patients who die of colorectal cancer with liver-only disease, it seems appropriate to be developing and investigating methods of local liver tumor ablation. Selective internal radiation therapy (SIRT) is a relatively new, not widely used, modality suitable for use even in patients with extensive liver involvement. Fifty patients with advanced, nonresectable, colorectal liver metastases were treated with SIRT between February 1997 and June 1999. Estimated liver involvement was less than 25% in 30 patients, 25% to 50% in 13, and greater than 50% in seven. A single dose of between 2.0 and 3.0 GBq of 90yttrium microspheres was injected into the hepatic artery via a subcutaneous port and followed at 4-week intervals by regional chemotherapy with 5-fluorouracil. SIRT was well tolerated with no treatment-related mortality, although some treatment-related morbidity did occur including a 12% incidence of duodenal ulceration. Responses to SIRT were assessed by serial carcinoembryonic antigen (CEA) measurements and CT scans. Median CEA values 1 and 2 months after SIRT (expressed as percentage of initial CEA) were 19 and 13, respectively. Patients were assigned to one of two groups based on whether or not extrahepatic disease (EHD) developed within 6 months of SIRT. Median survival from SIRT for group 1 (EHD) (n = 26) was 6.9 months (range 1.3 to 18.8 months) and estimated survival +/- standard error at 6, 12, and 18 months was 57.7 +/- 3.8%, 23.1 +/- 4.8%, and 0%, respectively. For group 2 (no EHD) (n = 24), median survival was 17.5 months (range 1.0 to 30.3 months) with estimated survival at 6, 12, 18, 24, and 30 months of 79.2 +/- 2.9%, 66.7 +/- 3.6%, 55.9 +/- 3.3%, 25.2 +/- 4.4%, and 16.8 +/- 5.0%, respectively. This difference is statistically significant by log-rank test (P < 0.010). SIRT is a highly effective and well-tolerated regional treatment for extensive colorectal liver metastases. Tumor marker data suggest that substantial destruction of liver tumors can be achieved in more than 90% of patients by a single treatment. Survival times, particularly for those who do not develop extrahepatic metastases for some time, appear to be extended. SIRT warrants further use and investigation in patients with advanced colorectal liver metastases.

Adult↗

PubMedDate not supplied

Pancreatic secretory responses to intravenous hyperalimentation and intraduodenal elemental and full liquid diets.

Intravenous hyperalimentation and enteral elemental diets have both been advocated for the nutritional support of patients with acute pancreatitis, pancreatic fistula, and proximal small bowel fistula. The exocrine pancreatic responses to these nutrients compared to one another and to full liquid diet have been inadequately studied. Therefore, pancreatic protein, volume, and bicarbonate responses to graded doses of (1) intravenous hyperalimentation, (2) intraduodenal elemental diet, and (3) intraduodenal full liquid diet were compared in duplicate experiments in five dogs with chronic pancreatic fistulas. Both intraduodenal elemental and full liquid diets caused comparable and significant dose-related increases in pancreatic protein, volume, and bicarbonate outputs over basal levels (p less than 0.05). In contrast, there was no stimulation of pancreatic secretion by intravenous hyperalimentation. It therefore appears that of the methods studied, only intravenous hyperalimentation can provide full nutritional support while maintaining the pancreas at rest.

Animals↗

PubMedDate not supplied

Selective internal radiation therapy (SIRT) with 90Yttrium microspheres for extensive colorectal liver metastases.

BACKGROUND/AIMS: SIRT (selective internal radiation therapy) is a new modality for the treatment of nonresectable liver tumors which has been reported to achieve high response rates. We report our initial experience in patients with extensive colorectal liver metastases. METHODOLOGY: Thirty-eight (38) patients were treated with SIRT between February 1997 and November 1998. Liver involvement was < 25% in 19 patients, 25-50% in 9 and > 50% in 10. Patients received 90Yttrium microspheres into the hepatic artery via an arterial port and subsequent 4-weekly cycles of hepatic artery chemotherapy with 5-fluorouracil. RESULTS: SIRT was well tolerated and no treatment-related mortality was observed. Responses to SIRT as indicated by falling tumor markers and serial 3-monthly computed tomography scans were seen in over 90% of patients. Estimated survival at 6, 12 and 18 months was 70%, 46% and 46%, respectively, and was principally determined by the development of extrahepatic metastases. CONCLUSIONS: SIRT is well tolerated in patients with extensive colorectal liver metastases and achieves encouraging liver tumor responses, which are well maintained by hepatic artery chemotherapy. The modality warrants wider use and investigation.

Adult↗

PubMedDate not supplied

Development of a dendritic cell (DC)-based vaccine for patients with advanced colorectal cancer.

BACKGROUND/AIMS: An ability to induce a specific immune response to cancer would provide an important new dimension in its management. We report our initial work investigating the safety and efficacy of a dendritic cell vaccine in patients with colorectal cancer. METHODOLOGY: Fifteen (15) patients with advanced colorectal cancer had vaccines prepared from autologous dendritic cells pulsed with tumor RNA and keyhole limpet hemocyanin. Vaccines were administered intravenously and patients were observed in hospital for 2 days. Thereafter, consultations were at monthly intervals at which time booster doses were given to a total of 4. Patients were monitored with weekly blood tests, including carcinoembryonic antigen, and 3-monthly computed tomography scans. RESULTS: Flow cytometry confirmed dendritic cell phenotype and in vitro function was confirmed by mixed lymphocyte reaction. No major adverse effects were observed. Eleven of 13 patients tested developed a positive keyhole limpet hemocyanin skin test and in 7 the carcinoembryonic antigen fell suggesting some in vivo anticancer effect. To date no dramatic clinical responses have been observed but follow-up is very short. CONCLUSIONS: The therapy was well tolerated. Dendritic cells were verified by phenotype and in vitro function. The positive keyhole limpet hemocyanin skin test confirms in vivo function by effective vaccination to keyhole limpet hemocyanin. Demonstration of any anticancer efficacy will require further follow-up.

Adult↗