Histopathological in myeloma cases, immunohistochemical, clinical and flow cytometric retrospective evaluation of findings

Objective: In our study, we aimed to retrospectively evaluate the histopathological, immunohistochemical, clinical and flow cytometric findings in myeloma cases diagnosed in our clinic and to contribute to the literature with these findings. Materials and Methods: In this study, bone marrow biopsy, immunohistochemical staining results, clinical findings of the patients and flow cytometry analyzes of 115 myeloma cases diagnosed between 2017 and 2023 at AFSU Faculty of Medicine, Department of Medical Pathology were re-evaluated. The data obtained in the statistical evaluation were calculated using the SPSS v.25 program and a p value of <0.05 was considered significant. Results: As a result of the analysis, the frequency of the disease was found to be higher in the male gender (63%). The age range of our patients was 41-89 and the overall average age was 68.2±10.8. The most common IgG myeloma subtype was detected. As a result of immunohistochemical evaluation; Cyclin D1 was found to be positive in 18%, CD117 in 42% and CD56 in 66%, CD20 in 14% and CD19 in 8%. Reticulin grade 2 fibrosis was most frequently detected in patients; The degree of fibrosis was found to be higher in women and in patients with CD56(-), CD117(-) and Lambda (-). Diagnosis could not be made in 17 of 52 patients who underwent flow cytometry study. The diagnosis rate was 67%. The average atypical plasma cell rate was 66% in biopsy, 47% in cytology, and 20% in flow cytometry. A strong positive correlation was found between the atypical plasma cell ratio in the biopsy and the atypical plasma cell ratio in cytology (r = 0.624, p = 0.00). In our study group, stage 3 patients were most frequently detected (64%) and the median survival time was reported as 22 months. Survival was found to be shorter and the stage was more advanced in patients with CD56 (-) (p=0.002). It was determined that the disease was at a statistically significant advanced stage in patients with CD56+CD117+Cyclin D1 triple negative (p=0.043). Survival was found to be shorter in patients with advanced stage (p=0.001). Conclusion: There is no statistical significance between gender and survival time and mortality rate. Myeloma subtype has no association with survival. In patients with CD56 negative, in patients with CD56 and CD117 double negative, in patients with CD56, CD117 and Cyclin D1 triple negative, in patients with Cyclin D1 (-), in patients with high fibrosis, in advanced stage patients, CRAB findings (hypercalcemia, high creatinine, anemia) Survival was found to be shorter in patients with low albumin levels, high beta 2 microglobulin levels, and high CRP levels. Bone involvement is statistically significantly higher in patients with CD20 (-). There is a strong positive correlation between the biopsy and the plasma cell ratio in cytology, and a weak positive correlation between the biopsy and the plasma cell ratio in flow cytometry. The results we obtained from our study will expand the data in the literature and shed light on research on this subject.