Abstract

Aim: To assess the significance of collagen type I carboxy terminal telopeptide (ICTP) as a diagnostic marker of osteolysis, as well as its relation to disease progression and response to treatment in multiple myeloma (MM).

Subject and methods: ICTP was measured in 40 newly diagnosed MM patients (including 22 patients with osteolytic lesion), and 20 age- and sex- matched controls. Patients were followed up for detection of their response to treatment.

Results: The median and IQR levels of ICTP were significantly elevated in MM patients compared with controls (0.65 [0.15-0.8] ng/mL versus 0.05 [0.04-0.07] ng/mL, p<0.001), with significant higher median levels among patients with osteolytic lesion compared with myeloma patients without osteolytic lesion (0.7 [0.65 – 1.0] ng/mL versus 0.1 [0.1 -0.2] ng/mL, p<0.001). According to ROC curve analysis, ICTP at a cutoff 0.3 ng/mL could detect osteolytic lesion with high sensitivity and specificity. ICTP was positively correlated with markers of renal impairment, hypercalcemia, anemia, thrombocytopenia and poor prognostic factors; lactate dehydrogenase (LDH), C reactive protein (CRP), hypoalbuminaemia, and β2-microglobulin (β2M) (p<0.05). Using logistic regression analysis, ICTP was found to be a significant predictor of osteolysis. Moreover, initial ICTP levels were higher in progressive/relapsed myeloma patients compared with responsive/stable patients (p<0.001).

Conclusion: We suggest that ICTP is a reliable marker that can be used in the diagnosis and prediction of osteolytic lesion and prediction of treatment response in MM.