Diagnostic and Prognostic Challenges in Cytology for Multiple Myeloma: A Case Series in a Resource-limited Setting

Background: Multiple myeloma (MM) is a malignancy of plasma cells characterized by clonal proliferation in the bone marrow and associated organ damage. In resource-limited settings, advanced diagnostic tools are often inaccessible, making conventional cytology a critical first-line diagnostic approach. Objectives: To assess the advantages and limitations of using bone marrow cytology as the primary diagnostic method for MM in a resource-constrained environment. Methods: A retrospective case series of four patients with suspected MM was conducted at a regional hospital in Senegal. Diagnosis was based exclusively on bone marrow cytologic evaluation using standard staining techniques. Demographic data, cytologic findings, and available clinical information were analyzed in comparison to established diagnostic criteria. Results: Case 1 had 15% plasma cells but no clear CRAB features, suggesting smoldering MM. Case 2 exhibited 35% plasma cell infiltration, but staging was not possible due to the absence of biochemical and immunophenotypic data. Case 3 demonstrated significant plasmacytosis with pancytopenia, raising concerns about aggressive disease versus metastatic marrow involvement. Case 4 presented with systemic symptoms indicative of plasma cell leukemia, but cytologic evaluation alone was insufficient for definitive classification. Conclusions: Although bone marrow cytology is a rapid and accessible diagnostic tool in low-resource settings, it is inadequate for risk stratification and precise subclassification of MM. Additional diagnostic techniques—such as basic immunophenotyping and serum studies—are necessary to optimize patient management and inform healthcare policy improvements.