Hyperfractionated Treatment with 177Lu-Octreotate Increases Tumor Response in Human Small-Intestine Neuroendocrine GOT1 Tumor Model

Radionuclide treatment of patients with neuroendocrine tumors has advanced in the last decades with favorable results using 177Lu-octreotate. However, the gap between the high cure rate in animal studies vs. patient studies indicates a potential to increase the curation of patients. The aim of this study was to investigate the tumor response for different fractionation schemes with 177Lu-octreotate. BALB/c mice bearing a human small-intestine neuroendocrine GOT1 tumor were either mock treated with saline or injected intravenously with a total of 30–120 MBq of 177Lu-octreotate: 1 × 30, 2 × 15, 1 × 60, 2 × 30, 1 × 120, 2 × 60, or 3 × 40 MBq. The tumor volume was measured twice per week until the end of the experiment. The mean tumor volume for mice that received 2 × 15 = 30 and 1 × 30 MBq 177Lu-octreotate was reduced by 61% and 52%, respectively. The mean tumor volume was reduced by 91% and 44% for mice that received 2 × 30 = 60 and 1 × 60 MBq 177Lu-octreotate, respectively. After 120 MBq 177Lu-octreotate, given as 1–3 fractions, the mean tumor volume was reduced by 91–97%. Multiple fractions resulted in delayed regrowth and prolonged overall survival by 20–25% for the 120 MBq groups and by 45% for lower total activities, relative to one fraction. The results indicate that fractionation and hyperfractionation of 177Lu-octreotate are beneficial for tumor reduction and prolongs the time to regrowth.

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Effect of ileal infusion of lipid on jejunal motor patterns after a nutrient and nonnutrient meal

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1988.255.6.g800 ◽

1988 ◽

Vol 255 (6) ◽

pp. G800-G806 ◽

Cited By ~ 3

Author(s):

I. M. Welch ◽

P. A. Davison ◽

J. Worlding ◽

N. W. Read

Keyword(s):

Small Intestine ◽

Small Bowel ◽

Contraction Rate ◽

Small Bowel Transit ◽

Motor Patterns ◽

Motility Pattern ◽

Human Small Intestine ◽

The Mean

To investigate how ileal lipid delays small bowel transit, pressure activity was recorded at multiple sites in the human small intestine during ileal infusion of either lipid or saline. Initial studies showed that ileal lipid reduced the contraction rate in the jejunum but not in the duodenum or ileum. The effect of ileal lipid was further investigated by recording pressures at seven sites in the jejunum after ingestion of either a nutrient or a nonnutrient meal. The nutrient meal induced an irregular motility pattern; ileal lipid significantly reduced the contraction rate, the percentage of contractions involved in propagated events, the mean length of propagation, and the propagation index. The nonnutrient meal induced a pattern containing discrete clusters of contractions. Ileal lipid significantly reduced the occurrence of contraction clusters and the mean length of propagation. Thus, although the delay in small bowel transit observed during ileal infusion of lipid can be explained by reductions in the rate and the degree of propagation of jejunal contractions, the mechanism varies according to the type of meal.

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Electron probe x-ray microanalysis and electron microscopy of amino acid absorption and transport by the small intestine: inhibition by chemical poisons and correlation to the elemental composition of the epithelial cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142311 ◽

1986 ◽

Vol 44 ◽

pp. 134-135

Author(s):

A. J. Tousimis

Keyword(s):

Small Intestine ◽

Amino Acid ◽

Epithelial Cells ◽

Elemental Composition ◽

Isotope Labeling ◽

Structural Components ◽

X Ray ◽

Human Small Intestine ◽

Transport Studies

The elemental composition of amino acids is similar to that of the major structural components of the epithelial cells of the small intestine and other tissues. Therefore, their subcellular localization and concentration measurements are not possible by x-ray microanalysis. Radioactive isotope labeling: I131-tyrosine, Se75-methionine and S35-methionine have been successfully employed in numerous absorption and transport studies. The latter two have been utilized both in vitro and vivo, with similar results in the hamster and human small intestine. Non-radioactive Selenomethionine, since its absorption/transport behavior is assumed to be the same as that of Se75- methionine and S75-methionine could serve as a compound tracer for this amino acid.

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Bacterial flora of the human small intestine

JAMA ◽

10.1001/jama.196.13.1125 ◽

1966 ◽

Vol 196 (13) ◽

pp. 1125-1127 ◽

Cited By ~ 3

Author(s):

G. H. Bornside

Keyword(s):

Small Intestine ◽

Bacterial Flora ◽

Human Small Intestine

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Gamma knife radiosurgery for craniopharyngiomas

Journal of Neurosurgery ◽

10.3171/jns.2000.93.supplement_3.0047 ◽

2000 ◽

Vol 93 (supplement_3) ◽

pp. 47-56 ◽

Cited By ~ 107

Author(s):

Wen-Yuh Chung ◽

David Hung-Chi Pan ◽

Cheng-Ying Shiau ◽

Wan-Yuo Guo ◽

Ling-Wei Wang

Keyword(s):

Clinical Outcome ◽

Gamma Knife ◽

Tumor Volume ◽

Gamma Knife Radiosurgery ◽

Tumor Control ◽

Content Type ◽

Stereotactic Aspiration ◽

Cystic Component ◽

The Mean ◽

Fine Print

Object. The goal of this study was to elucidate the role of gamma knife radiosurgery (GKS) and adjuvant stereotactic procedures by assessing the outcome of 31 consecutive patients harboring craniopharyngiomas treated between March 1993 and December 1999. Methods. There were 31 consecutive patients with craniopharyngiomas: 18 were men and 13 were women. The mean age was 32 years (range 3–69 years). The mean tumor volume was 9 cm3 (range 0.3–28 cm3). The prescription dose to the tumor margin varied from 9.5 to 16 Gy. The visual pathways received 8 Gy or less. Three patients underwent stereotactic aspiration to decompress the cystic component before GKS. The tumor response was classified by percentage reduction of tumor volume as calculated based on magnetic resonance imaging studies. Clinical outcome was evaluated according to improvement and dependence on replacement therapy. An initial postoperative volume increase with enlargement of a cystic component was found in three patients. They were treated by adjuvant stereotactic aspiration and/or Ommaya reservoir implantation. Tumor control was achieved in 87% of patients and 84% had fair to excellent clinical outcome in an average follow-up period of 36 months. Treatment failure due to uncontrolled tumor progression was seen in four patients at 26, 33, 49, and 55 months, respectively, after GKS. Only one patient was found to have a mildly restricted visual field; no additional endocrinological impairment or neurological deterioration could be attributed to the treatment. There was no treatment-related mortality. Conclusions. Multimodality management of patients with craniopharyngiomas seemed to provide a better quality of patient survival and greater long-term tumor control. It is suggested that GKS accompanied by adjuvant stereotactic procedures should be used as an alternative in treating recurrent or residual craniopharyngiomas if further microsurgical excision cannot promise a cure.

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