Laboratory Features of Newly Diagnosed Multiple Myeloma Patients

Abstract

Objectives: Multiple myeloma (MM) is a malignant disorder characterized by proliferation of a single clone of plasma cells derived from β-cells in the bone marrow. It is the second most common adult hematological malignancy, and it is the most common cancer with skeletal components as its primary site. The purpose of the retrospective study was to assess the hematological profile, different biochemical parameters, and the serum electrophoresis patterns of patients consistent with clinical symptoms of multiple myeloma.

Materials and methods: A retrospective study of 99 patients diagnosed with multiple myeloma (MM) was carried out at the Hematology Department of Benghazi Medical Center (BMC) in Benghazi, Libya from January 2010 to March 2017. Information on the laboratory features was obtained at presentation (before treatment) and analyzed.

Results: Of the 99 study detected cases of multiple myeloma at diagnosis, 14% were younger than 45 years and 35% were 70 years or older. The mean age was 61 years, of which 42 (42.4%) were males and 57 (57.6%) were females. Anemia was seen in roughly half of the diagnosed cases, most of which was normocytic normochromic anemia. High erythrocyte sedimentation rate (ESR) was seen in 65.3% of cases and increased neutrophil-to-lymphocyte ratio (NLR) was seen in 29.7%. Other abnormal serum levels with regard to the cases are as follows: hyperproteinemia in 30%, low albumin/globulin (A/G) ratio in 54.2%, hypercalcemia in 11.3%, serum creatinine level of >2.0 mg/dL in 27.2% cases, and increased β2-microglobulin in 67%. Serum protein electrophoresis revealed a localized band in 70.8% of patients. Monoclonal bands were seen in 44 cases (95.7%) and a bi-clonal pattern in two cases (4.3%), 78% of M-band showed migration to γ-region of electrophoretogram and 18% to β-region. Hypogammaglobulinemia was detected in 32.8% and hypergammaglobulinemia was detected in 49.2%. Of the hypergammaglobulinemia, 18.1% showed polyclonal gammaglobulinemia. Bence Jones protein was positive in 50% cases. IgG was the commonest type, followed by IgA then light chain. In 26.5% of cases, the only diagnosis was multiple myeloma. Light chain multiple myeloma patients had high α2 globulin concentration and normal A/G ratio. Apart from the diagnosis of multiple myeloma, a number of cases had varying diagnoses including the following: 4% non-secretory myeloma, 2% amyloidosis with nephrotic syndrome, 2% liver cirrhosis, and 18.2% renal failure. Most patients presented in stage III.

Conclusions: The presence of anemia, high ESR, and low A/G ratio in elderly patients should alert the clinician to investigate along the lines of multiple myeloma. In this study, unfortunately, the laboratory investigations were insufficient for diagnosing this disease in most patients. Most patients were diagnosed at stage III. Absence of paraprotein in the blood does not exclude multiple myeloma. It was further observed that most of the patients presented with significant renal damage, which attributed to hyperuricemia, hypercalcemia, or high NLR. Multiple causes of renal failure occur in myeloma and are often present at the time of diagnosis.

Keywords: esr; hypercalcemia; multiple myloma; nlr; non-secretory myeloma.

Figure 1. Distribution of patients (n=79) according to the major cities of Libya

Figure 2. Location of M-spike in serum protein electrophoresis (N=45)

Figure 3. Plasma cell in bone marrow aspirate (n=71)