Immunological detection of bone marrow lesions in skin melanoma and its clinical significance: Observational study

Background. Melanoma of the skin is characterized by a rapid progression and early metastasis. It has been shown the disseminated tumor cells, which are often found in the bone marrow, has an important prognostic value. The study of disseminated tumor cells in melanoma might be one of the possible additional sources of information about the nature of the disease and potential application points for drug therapy. Aim. To study the frequency of detection of disseminated tumor cells in the bone marrow in melanoma, depending on the clinical and morphological characteristics of the tumor. Materials and methods. The study included 67 patients with a verified diagnosis of melanoma who were examined and treated at the Blokhin National Medical Research Center of Oncology from 2014 to 2019 years. Male patients accounted for 50.7% (n=34), female patients 49.3% (n=33). The average age of patients: 50.11.6 years. Immunological and morphological examination of the bone marrow were perfomed. Morphological examination was performed by two independent morphologists. Disseminated tumor cells were evaluated by flow cytometry among all nucleated cells (Syto41+) based on the expression of the HMB-45 antigen and the absence of expression of the CD45 panleukocyte antigen (FACS Canto II, USA, Kaluza Analysis v2.1). Statistical data processing was performed using the IBM-SPSS Statistics v.21 Results. Morphologically bone marrow damage was not detected in any case. Disseminated tumor cells (CD45-HMB-45+) in the bone marrow of melanoma patients were detected in 62.7% (n=42) of cases by flow cytometry. The frequency of bone marrow damage in the early stages is not lower than in advanced ones (p=0.029). This is clearly seen in the enlarged analysis. The percentage of DTC detection. At stages I and II was 60.0% (6/10) and 84.6% (11/13), respectively, at stages III and IV 44.4% (8/18) and 65.4% (17/26). In addition, the frequency of detection of disseminated tumor cells in the bone marrow was higher in young patients (p=0.02). There was no correlation between the frequency of bone marrow damage depending on BRAF status. Conclusion. The connection of disseminated tumor cells with the clinical and morphological characteristics of the melanoma has been established. Melanoma is characterized by frequent bone marrow damage, even in the early stages, in young patients.