Synthesis and characterization of multiply-tyrosinated, multiply-iodinated somatostatin analogs.

Radio-labeled somatostatin analogs have recently gained popularity as agents useful in intraoperative tumor localization, external scintigraphy and in situ radiotherapy. We have synthesized and characterized a series of novel N-terminally extended multiply-tyrosinated somatostatin analogs that possess high binding affinity for somatostatin receptors, exhibit biological activity comparable to the native peptide and retain these characteristics after iodination. These analogs can be radio-iodinated to high specific activities. Following radioiodination, these analogs exhibit minimal radiolysis and may be clinically useful for tumor localization, scanning and therapy.

Experiences with high dose radiopeptide therapy: the health physics perspective.

One of the new, promising areas of nuclear medicine involves radiolabeled low-molecular-weight peptides for the diagnosis and management of cancer. Somatostatin analogous peptides bind to membrane receptors on tumors with high specificity. These analogues, when radiolabeled with 123I, 131I, 99mTc, or (111)In, allow for external scintigraphic imaging or radioguided surgical resection of tumors. Somatostatin analogues with high tumor binding affinity have also been used for high-dose radiotherapy at the Medical Center of Louisiana since 1994. Although we had extensive prior experience with relatively high-dose 131I administration for thyroid ablation, our personnel protection, contamination control, and other safety techniques required significant modification to ensure effective contamination and radiation exposure control. As therapy with radiolabeled peptides becomes more widely utilized, the controls developed at our institution may be implemented by others to maintain exposures ALARA.

Treatment of metastatic carcinoid tumors using multimodality therapy of octreotide acetate, intra-arterial chemotherapy, and hepatic arterial chemoembolization.

BACKGROUND: Overall survival and quality of life in patients with metastatic carcinoid tumors depend on control of tumor growth and suppression of amine-induced symptoms. METHODS: We report on a series of 10 patients with carcinoid tumors metastatic to the liver who were treated with long-term octreotide acetate therapy (100 to 500 micrograms three times a day), sequential intra-arterial 5-fluorouracil (5-FU) infusions, and hepatic tumor chemoembolization. RESULTS: All 10 patients remained asymptomatic or had extremely mild symptoms after combined modality therapy (mean follow-up duration of 51.5 months). Sixty percent of the patients had a > 50% reduction of their tumor size (mean duration 42 months). An additional 30% experienced stabilization of tumor growth for 6 months or longer. Five of the 10 patients are currently alive. The mean group survival is 58 months since diagnosis (range 33 to 115) and 40 months since starting therapy (range 12 to 65). CONCLUSIONS: Combining octreotide acetate, intra-arterial 5-FU, and tumor chemoembolization effectively retards tumor growth while providing excellent symptom control.

Endoscopic removal of an infarcted appendix epiploica.

Infarction of an appendix epiploica is a rare event that is seldom diagnosed preoperatively. Report herein is a case of a 76-year-old male complaining of abdominal pain. The etiology of this pain was unclear but the diagnosis of epiploitis was preoperatively suspected. The infarcted epiploic appendix was identified and resected laparoscopically.

Consistency in recalling features of former head injuries: retrospective questionnaire vs. interview retest.

The probability and features of memory concerning former head injuries with loss of consciousness was assessed in two formats: a group-test questionnaire and a retest using personal individual interview. Results are given concerning the greater likelihood of reporting short 'permanent' retrograde amnesias in the interview.