Archana Bhaskar¹, Ritu Gupta², Lalit Kumar³, Atul Sharma³, Sonu Chand Thakur^4
1Laboratory Oncology Unit; Center for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India.
²Laboratory Oncology Unit, Dr. B.R.A. IRCH All India Institute of Medical Sciences, New Delhi, India.
³Department of Medical Oncology, Dr. B.R.A. IRCH All India Institute of Medical Sciences, New Delhi, India.
⁴Center for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India.

ABSTRACT

Neoangiogenesis plays a governing role in pathogenesis and progression of disease in multiple myeloma. Tumor angiogenesis has been studied using microvessel density (MVD), circulating endothelial progenitor cells (cEPC) and angiogenic cytokines. Increased microvascular density of the bone marrow has also been correlated with poor survival in multiple myeloma patients. Assessment of circulating endothelial progenitor cells (EPC) is a less- invasive method and can be used to assess the dynamic changes in angiogenesis and was, therefore, evaluated in this study to serve as prognostic marker in multiple myeloma. A total of 75 newly diagnosed MM patients registered at Dr.B.R.A.IRCH, AIIMS were enrolled in this study. For each patient, a baseline peripheral blood was drawn prior to therapy and for 55 of these patients, sample was obtained after chemotherapy with median follow-up of 4 months (range 2-7 months). Circulating EPC were identified as CD45- to dim cells with co-expression of CD34, CD133, CD31 and VEGFR2 and expressed as number of cells/μl of peripheral blood mononuclear cells by flow cytometery. Progression free survival (PFS) was calculated from the date of diagnosis to disease progression or death from any cause and overall survival (OS) was calculated from date of diagnosis to death or last follow up of patients. The response duration was measured from the date of achievement of response to disease progression or death from any cause. At 2 years, 8/75 died and 24/75 progressed. After median follow-up of 8 months (range 1-32 months), the median OS has not reached and PFS was 18 months. No correlation was established between baseline cEPC numbers and PFS and OS. The cut-off value of cEPC numbers at baseline correlated significantly with response duration (p<0.006, n=59); the median response duration was 23 months for the group with ≤19.6 cEPC/μl (n=44) compared to 14 months for the group with >19.6 cEPC/μl (n=15). The cut-off value of cEPC numbers after therapy also correlated with response duration (p=0.001, n=55); the median response duration was 23 months for the group with cEPC/μl ≤6.5 (n=39) compared to 9 months for the group with >6.5 cEPC/μl (n=16). This study suggests that the cEPC numbers correlates with response duration and may serve as prognostic biomarker of treatment outcome in MM. Read more…