A Pilot Study Assessing a Special PET Scan to Help Guide the Biopsy of Histiocytic Disorders

Full Title

Pilot Study of 18F-Fluorocholine PET to Improve Accuracy of Diagnostic Biopsy in Histiocytic Disorders


Histiocytosis is a general name for a group of diseases that involve an abnormal increase in the number of immune cells called histiocytes. Examples include Erdheim-Chester disease and Langerhans cell histiocytosis. These diseases can be challenging to diagnose accurately. Doctors typically use positron emission tomography (PET) scanning to locate an area of tissue to be biopsied, but it can sometimes be difficult to distinguish true histiocytosis from other kinds of cells in that area due to inflammation when “regular” PET scans are used. As a result, many patients with these diseases have had several biopsies performed without a clear diagnosis. In addition, even when a biopsy leads to a diagnosis, the biopsy material may be unfit for important tests (such as gene testing).

In this study, researchers are evaluating a different type of PET scan to see if it is more effective for distinguishing active histiocytes from inflammation, and therefore in helping make biopsies more accurate. The special PET scan uses an investigational radioactive tracer called F-choline. Researchers want to observe how F-choline is distributed in the body and see if it can help them better distinguish between histiocytic and non-histiocytic cells. If so, it could provide more information to doctors trying to identify the tumor cells that are most important to collect during a biopsy. Participants in this study will have both a regular PET scan and the special PET scan before a biopsy.


To be eligible for this study, patients must meet several criteria, including but not limited to the following:

  • Patients must have suspected or confirmed Erdheim-Chester disease, Langerhans cell histiocytosis, or a similar histiocytic disorder that requires diagnostic imaging and biopsy.
  • This study is for patients age 18 and older.

For more information about this study and to see if you are eligible, please contact Dr. Eli Diamond at 212-610-0243.





Disease Status

Newly Diagnosed