Important Pathologic Considerations for Establishing the Diagnosis of Myelofibrosis

Prognostic significance of bone marrow fibrosis in diffuse large B-cell lymphoma

INTRODUCTION

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphomas. The aim of this study is to determine the relationship between the increase in the degree of fibrosis in the bone marrow and prognosis and mortality in newly diagnosed DLBCL.

METHODS

Bone marrow biopsy of 153 newly diagnosed DLBCL patients was determined by staining with reticulin, Masson's trichrome histochemical stain, and the degree of fibrosis was determined.

RESULTS

In the bone marrow biopsy performed at the time of diagnosis, bone marrow fibrosis (BMF) was observed in 70 patients. While BMF-1 was detected in 42 patients (60%), BMF-2 was detected in 25 patients (35%) and BMF-3 was detected in 3 patients (4%). As the degree of BMF increased, the median overall survival and median progression-free survival times were significantly shorter (p: 0.008), (p < 0.001). In patients with an increased degree of BMF, a significant decrease in leukocyte and neutrophil counts was observed after chemotherapy (p: 0.004). According to the results of the multivariate Cox regression model, it was determined that high NCCN-IPI risk (HR: 8.25; %95 CI: 1.09-62.52; p = 0.041) and being BMF ≥ 2 (HR: 3.75; %95 CI: 1.65-8.51; p = 0.002), increased the risk of death (p = 0.002, -2 loglikelihood = 392,553).

CONCLUSION

When the literature was reviewed, it was seen that this study was the first to define that bone marrow fibrosis grade 2 and above in DLBCL is a prognostic marker associated with worse survival. In the bone marrow pathology, which is examined to detect advanced disease in DLBCL, besides lymphomatous involvement, the detection of fibrosis grade is very important.