Know Cancer

forgot password

Selective Venous Catheterization for the Localization of Phosphaturic Mesenchymal Tumors

8 Years
Not Enrolling
Osteomalacia, Neoplasms

Thank you

Trial Information

Selective Venous Catheterization for the Localization of Phosphaturic Mesenchymal Tumors

Phosphaturic mesenchymal tumors elaborate phosphate lowering factors (phosphatonins) which
lead to tumor induced osteomalacia/osteogenic osteomalacia (TIO/OOM). Patients with TIO/OOM
suffer years of significant morbidity and debilitation unless their tumors, which are
notoriously difficult to locate, are removed.

Selective venous catheterization has been used to localize hormonally active neoplasms by
demonstrating a gradient in the concentration of the hormone of interest between the vessel
immediately draining the tumor site and the peripheral circulation. The primary objective
of this protocol is to evaluate the utility of combining selective venous catheterization
with biochemical assays that identify phosphatonins in the serum as a way to identify
phosphatonin gradients and thereby localize phosphaturic tumors.

Our study population will consist of TIO/OOM patients with non-localized phosphaturic tumors
as well as five patients whose lesions have been identified with some certainty by
conventional imaging techniques. These individuals will undergo selective venous
catheterization during which blood samples will be obtained and processed for the presence
of phosphatonins. The primary endpoint will be met if a gradient indicating a possible
tumor is found, focused clinical imaging in the appropriate anatomical sub-region identifies
a lesion, and the lesion is confirmed to be a phosphaturic mesenchymal tumor upon surgical

Inclusion Criteria


Patients must have the clinical diagnosis of TIO/OOM to be considered for enrollment in
this study. The diagnosis will be based upon a clinical history including some or all of:
rickets (children), pathological fractures, bone pain, muscle weakness, low serum
phosphorus with concomitant inappropriately high urine phosphorus, low or inappropriately
low-normal serum vitamin 1,25 (OH)(2)-vitamin D3, and an elevated FGF-23 level in the
absence of a family history of a phosphate wasting syndrome. Along with the clinical
symptoms listed above, the patient must have undergone routine clinical imaging.

Inclusion will be limited to all patients in whom a likely lesion was not localized by
imaging, plus five patients for whom a likely lesion has been identified by imaging.
Patients with a likely lesion identified will serve as positive controls.

Patients must be able to give informed consent.


Patients with co-morbidities that would increase the risk of selective venous
catheterization will be excluded from the study. This includes but is not limited to
medical conditions such as: poorly controlled diabetes, renal insufficiency, chronic
obstructive pulmonary disease, anemia, hypertension, clotting disorders, etc.

Pregnancy is a contraindication to this venous catheterization procedure. A serum
Beta-Hcg will be required for all eligible women of childbearing age unless documentation
of a hysterectomy or other condition that makes pregnancy impossible is provided.

Inability or unwillingness to give informed consent will exclude patients from this study.
Female patients who will not allow pregnancy testing and will not provide documentation
indicating a medical condition that makes pregnancy impossible will not be eligible for
this study.

Type of Study:


Study Design:



United States: Federal Government

Study ID:




Start Date:

December 2004

Completion Date:

Related Keywords:

  • Osteomalacia
  • Neoplasms
  • Tumor Induced Osteomalacia
  • FGF-23
  • Phosphatonin
  • Hypophosphatemia
  • Oncogenic Osteomalacia
  • Phosphaturic Mesenchymal Tumor
  • TIO
  • Osteogenic Osteomalacia
  • OOM
  • Neoplasms
  • Osteomalacia
  • Neoplasms, Connective Tissue



National Institutes of Health Clinical Center, 9000 Rockville Pike Bethesda, Maryland  20892