The US PET Scan Project

11C-5-HTP-PET scan
Update February 26 , 2006

 

Progress Notes February 26, 2006:
The first of its kind in North America, the 11C-5-HTP-PET scan (previously only available in Uppsala Sweden) also known to the US carcinoid community as "the PET SCAN PROJECT" (not to be confused with the standard FDG PET scan) is now in clinical trials since December 2005. We are happy to announce that the scan IS WORKING and the first results from the ongoing trials will be presented at the Carcinoid Cancer Foundation's patient symposium on April 2 at Mount Sinai Hospital in New York City. We encourange any North Easterners to attend this meeting to share with us this exciting and groundbreaking news. To see program and registration information CLICK HERE (for flyer) and HERE (for registration)

 


Update November 28, 2005


Prgress notes November 10, 2005

RE: The status of the Pet Scan Project at Cornell

Dear Dr. Warner and the Carcinoid/NET Community

The synthesis proved to be difficult but we have successfully synthesized the 11C-5-HTP. The paper work and approvals involved are even greater than we anticipated but we have successfully passed it through the first medical center review committee. It is now with the IRB and we expect approval within weeks.
I think that it is realistic that we will be able to begin patient studies in January 2006. The materials are costly and currently it seems that we will be limited to one patient per day. We are not yet sure how many days per week we can sustain it. We will keep you informed.

Sincerely

Stanley J. Goldsmith, MD
Director, Nuclear Medicine
Professor, Radiology and Medicine
New York Presbyterian Hospital-Well Cornell Medical Center
525 East 68th Street
New York, N.Y. 10021

 


PET SCAN PROJECT

The goal of Dr. Vallabhajosula’s research project is “to establish the synthesis procedure of preparing a radioactive imaging agent by attaching a radioactive atom (Carbon-11) to a 5-HTP molecule.” The synthesis of this molecule is highly complex, involving numerous steps. Dr. Vallabhajosula hopes to complete all procedures, including obtaining permission from the institutional human research review committee and the Food and Drug Administration (FDA) by the end of June 2005 and be ready to begin clinical studies in patients starting in early July.

PET (positron emission tomography) scans with 5-HTP are currently only available in Europe (Sweden) but not in North America. In an article published in the March 8, 2005 issue of the Journal of Clinical Endocrinology & Metabolism, the authors (H. Orlefors, A. Sundin, U. Garske, C. Juhlin, K. Oberg, B. Langstrom, M. Bergstrom, and B. Eriksson) discussed how PET scans using 5-HTP compare with CT (computed tomography) and SRS (somatostatin receptor scintigraphy) i.e.OctreoScan. They concluded that PET scans with 5-HTP can be used as “a universal imaging method for detection of NET’s.” They also found that such scans are very “sensitive in imaging small NET-lesions, such as primary tumors, and can in a majority of cases image significantly more tumor lesions than SRS and CT.”
Full text of this article

Special recognition for funds raised for Dr. Vallabhajosula’s PET scan project goes to the members of the Capitol Area Carcinoid Support group (CACS) , Maryann and Bob Wahmann of the CCAN, the Carcinoid Cancer Awareness Network, Inc., for collecting the largest amount of donations from the carcinoid community and Bisc Deenahan of CALCF for also coordinating contibutions from many contributions. Jim Weiveris, secretary of NAAPNET and tristate coordinator of the Metro New York Carcinoid Support Group, worked countless hours helping to raise and coordinate funds donated for this project and his efforts are deeply appreciated.

Contributions achieved the initial goal of $30,000 for this project and the Carcinoid Cancer Foundation extends its gratitude to CCAN, CalCF, CACS, and the many other private donors and foundations. Thank you for helping to change how carcinoid and other neuroendocrine tumors are diagnosed. Your collective gifts will have a significant impact upon the lives of those with carcinoid and even the more rare NET’s.

Thank you Letters from Dr Shankar:

Letter 1

January 3rd 2005

Richard Warner, M.D.
Medical Director
Carcinoid Foundation
333 Mamaroneck Avenue, #492
White Plains, NY 10605

Dear Dr. Warner,

In December 2004, I have officially started a research project entitled "Synthesis of [IlC]5-Hydroxy Tryptophan (HTP) at CBIC of Weill Medical College of Comell University. We thank the Carcinoid Cancer Foundation and the Carcinoid Community very much for the gift of $30,000 towards this 5-HTP PET scan project. These funds will certainly help us to get started and get all the necessary supplies needed for the synthesis of this PET tracer. I will keep you informed ofthe progress in this project. As originally planned, my goal is to get all the necessary paperwork completed by June 2005 so that we can start the clinical studies in early July.

Once again, thank you and the "Carcinoid Community" for all the help and consideration.

Sincerely,

Shankar Vallabhajosula, Ph.D.
Chief of Radiochemistry at CBIC.

Description of the PET Scan Project:
Positron emission tomography (PET) studies with carbon-l I-labeled 5-HTP ([11C]5-HTP)

Patients with midgut carcinoid (MGC) tumors do contain “serotonin” or 5-hydroxytryptamine (5-HT) in the tumor tissue or have elevated levels in the plasma. One of the important chemicals in the food we consume is an amino acid called tryptophan. In the body, this amino acid is converted to another chemical called 5-hydroxytryptophan (5-HTP) by an enzyme. Serotonin is made in the cells using 5-HTP. Subsequently, serotonin is metabolized and converted to 5-Hydroxyindole acetic acid (5-HIAA), which is excreted in the urine and is a marker for detecting MGC tumors.

Our research project is to establish the synthesis procedure of preparing a radioactive imaging agent by attaching a radioactive atom (Carbon-11) to 5-HTP molecule. The synthesis of this molecule is a very complex procedure and involves many steps.

  • First we need to generate Carbon-11 radioactive atoms using an instrument called cyclotron.
  • The Carbon-11 atom is converted to a gas known as [11C]Carbon dioxide.
  • [11C]Carbon dioxide gas is then converted to a very reactive chemical known as [11C]Methyl iodide
  • [11C]Methyl iodide is then converted to another amino acid, known as [11C]Alanine.
  • [11C]Alanine is then finally converted to [11C]HTP using enzymes known as D-amino acid oxidase, glutamic pyruvic transaminase and tryptophanase enzymes.
  • The imaging agent, [11C]HTP is then purified and prepared for injection into the patient.
  • A number of quality control tests have to be performed to make sure that the compound injected into patient is very safe.

After we prepare this compound, we have to obtain permission from the institutional human research review committee and Food and Drug Administration (FDA). We hope to complete all these procedures by the end of June and ready for clinical studies in patients by July 2005.

This summary prepared by Shankar Vallabhajosula, Ph.D.

January 3rd 2005

Letter 2 Update:

March 24th 2005

Richard Warner, M.D.
Medical Director
Carcinoid Foundation
333 Mamaroneck Avenue, #492
White Plains, NY 10605

Dear Dr. Warner and Carcinoid Community

I just want to give you a progress report regarding the [1lC]5-RydroxyTryptophan (RTP). As of last week, we were finally able to complete the synthesis of the tracer as planned. Over the next 2-4 weeks, we will optimize the synthesis procedure, perform all the necessary quality control testing and prepare the paperwork for IRB ( Internal Review Board) submission/approval. The goal is to submit the application to IRB and FDA by May1st. If there are no major issues with FDA, we can start the clinical studies in early July.
Once again, thank you and the "Carcinoid Community" for all the help and consideration.

Sincerely,

Shankar Vallabhajosula, Ph.D.
Chief of Radiochemistry at CBIC.