ICTP as a Diagnostic Marker of Bone Resorption and Its Relation to Disease Progression and Treatment Response in Multiple Myeloma

Abstract

1 MD Clinical Pathology, Professor of Clinical Pathology, Clinical Pathology Dept, Ain Shams University 2 MD Clinical Pathology, Lecturer of Clinical Pathology, Clinical Pathology Dept, Ain Shams University Corresponding Author Gehan Mostafa Hamed 67 El Nasr St, Sheraton Heliopolis, Cairo, Egypt Email: gehanzeina@yahoo.com Mobile no.: 00202 01224954542 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 ageand sexmatched 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.