The effect of bone marrow fibrosis and angiogenesis on engraftment

OBJECTIVE AND HYPOTHESIS: The aim of this study was to investigate the effect of bone marrow fibrosis and angiogenesis on engraftment process in the hematlogical malignancies.METHODS: Fourty patients (median age 48,50±14,31 years, 23 male, 17 female) who had been transplanted with autologous and allogeneic peripheral stem cell between the years 2003-2008 in the hematology department of Dokuz Eylul University Medical School were enrolled into the study. The diagnoses of patients were multiple myeloma (n=26), amiloidosis (n=1), plasmocytoma (n=1), hodgkin?s lymphoma (n=6) and non-hodgkin?s lypmhoma (n=6).Bone marrow myelofibrosis was graded as score 0-3, angiogenesis was quantified by stereological method and calculated as an equivalent to the vascular surface area (VSD) per unit tumor volume (in cubic millimeters) and number of vessels per unit of stroma (NVES) at the recent bone marrow before transplantation. Subgroups of CD 34+ cell amount, fibrosis, and angiogenesis are examined with varience and correlation analysis in terms of effecting neutrophil and platelet engraftment days. Also fibrosis and angiogenesis examined in terms of survival analysis.RESULTS: We established among patients who were enrolled to this study that all of the patients had neutrophil engraftment while 37 patients had platelet engraftment. According to subgroup of reinfused graft CD 34+ cell analysis we established statistically significant differences between grup 1 (2,5-5x 106/kg) and grup 3 (>10x106/kg) in terms of neutrophil and platelet engraftment days. Between the CD 34+ cell amount and neutrophil and platelet engraftment days were found negative correlation. Twenty patients (%50) had grade 0, 14(%35) patiens had grade 1 and 6 patiens had grade 2 fibrosis in their bone marrow. We didn?t find any correlation with fibrosis between neutrophil and platelet engraftment days ( rs=0,09 p=0,57, rs=0,22 p=0,18, rs=0,25 p=0,14 respectively). The p value of platelet engraftment day was 0,059 ( Man Whitney U) in the subgrup analysis of patiens with grade 0 (n=20) and grade 2 ( n=6) fibrosis. There was no correlation with VSD and NVES between neutrophil and platelet engraftment days, also no statistically significant differences of subgroup of VSD and NVES in terms of engraftment days. But as interisting we saw that a positive correlation between fibrosis and angiogenesis. We didn?t statistically significant differences in the survival analysis of fibrosis and angiognesis subgroups.CONCLUSİON: There is no negative influence of fibrosis on the neutrophil engraftment. The delays of platelet engraftment may be seen in the patients who has advenced fibrosis. So we suggest that the CD 34+ cells cut off amount should be higher in this group patients.KEY WORDS: Engraftment, fibrosis, angiogenesis