Tartrate-resistant acid phosphatase isoform 5b: a novel serum marker for monitoring bone disease in multiple myeloma

Int J Cancer. 2003 Sep 1;106(3):455-7. doi: 10.1002/ijc.11247.


Tartrate-resistant acid phosphatase isoform-5b (TRACP-5b), a new marker reflecting osteoclast activity, and osteoprotegerin (OPG) were measured in 121 patients with multiple myeloma (MM) at diagnosis, and in 63 of them during pamidronate administration, to define their correlation with the extent of bone disease and disease activity in MM. Radiographic evaluation of the skeleton, measurement of other markers of bone remodelling, including N-terminal cross-linking telopeptide of type-I collagen (NTX), bone alkaline phosphatase and osteocalcin and of markers of disease activity (beta2-microglobulin, paraprotein, interleukin-6 (IL-6), were also performed. Levels of TRACP-5b were increased (p <.0001), while OPG was decreased in MM patients compared to controls (p <.01). TRACP-5b levels were associated with the radiographically assessed severity of bone disease (p <.0001) as well as with levels of NTX, IL-6 and beta2-microglobulin (p <.001, for each biochemical parameter, respectively). The combination of pamidronate with VAD-chemotherapy produced a reduction in TRACP-5b, NTX, IL-6, paraprotein and beta2-microglobulin levels from the 2nd month of treatment, with no effect on bone formation and OPG. A strong correlation was observed between changes in TRACP-5b and changes in NTX, IL-6 and beta2-microglobulin, while TRACP-5b predicted the disease progression in 5 patients. These findings suggest that TRACP-5b is increased in MM, reflects the extent of myeloma bone disease and may have a predictive value. TRACP-5b has also proved to be very useful for monitoring antimyeloma treatment, which had no effect on OPG levels.

Publication types

  • Comparative Study

MeSH terms

  • Acid Phosphatase / blood*
  • Adult
  • Aged
  • Aged, 80 and over
  • Alkaline Phosphatase / blood
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Biomarkers / analysis*
  • Biomarkers, Tumor / blood*
  • Bone Neoplasms / drug therapy
  • Bone Neoplasms / enzymology*
  • C-Reactive Protein / metabolism
  • Cytarabine / therapeutic use
  • Dexamethasone / therapeutic use
  • Diphosphonates / therapeutic use
  • Female
  • Glycoproteins / metabolism
  • Humans
  • Interleukin-6 / blood
  • Isoenzymes / blood*
  • Male
  • Middle Aged
  • Multiple Myeloma / drug therapy
  • Multiple Myeloma / enzymology*
  • Osteocalcin / blood
  • Osteoclasts / enzymology
  • Osteoclasts / metabolism
  • Osteogenesis / drug effects
  • Osteoprotegerin
  • Pamidronate
  • Paraproteins / metabolism
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Receptors, Tumor Necrosis Factor
  • Reference Values
  • Sensitivity and Specificity
  • Tartrate-Resistant Acid Phosphatase
  • Vincristine / therapeutic use
  • beta 2-Microglobulin / blood


  • Biomarkers
  • Biomarkers, Tumor
  • Diphosphonates
  • Glycoproteins
  • Interleukin-6
  • Isoenzymes
  • Osteoprotegerin
  • Paraproteins
  • Receptors, Cytoplasmic and Nuclear
  • Receptors, Tumor Necrosis Factor
  • TNFRSF11B protein, human
  • beta 2-Microglobulin
  • Cytarabine
  • Osteocalcin
  • Vincristine
  • Dexamethasone
  • C-Reactive Protein
  • Alkaline Phosphatase
  • ACP5 protein, human
  • Acid Phosphatase
  • Tartrate-Resistant Acid Phosphatase
  • Pamidronate

Supplementary concepts

  • VAD regimen