Synchronous presentation of multiple myeloma and lung cancer

Abstract

A 63-year-old male farmer presented to All India Institute of Medical Sciences (New Delhi, India) with fever, loss of appetite, and lower backache for 5 months. He was a chronic smoker and alcoholic for the previous 20 years. On physical examination, he had pallor, crepitations, bronchial breathing, and decreased breath sound on left side of chest. Chest x-ray showed mediastinal widening and left-sided pleural effusion. On computed tomography scan, large nodular mass in lower lobe of left lung and pleural effusion was seen (Fig 1). Laboratory investigations revealed hemoglobin level of 9.2 g/dL, total leukocyte count of 17.2 × 10⁹/L, and platelet count of 35 × 10⁹/L. Erythrocyte sedimentation rate was 116 mm at the end of first hour. Biochemical investigations showed raised adenosine deaminase levels in pleural fluid (45 U/L), raised serum alkaline phosphatase (1,050 U/L), total serum proteins of 84 g/L, and reversed albumin:globulin ratio (0.5). Prostate-specific antigen level was 0.16 ng/mL. Other serum biochemistry parameters were within normal limits. Peripheral blood smear showed normocytic normochromic erythrocytes, neutrophilia, and rouleaux formation. Bone marrow aspirate was cellular and showed hematopooietic cells of all series, increased plasma cells (25%), and few clusters of metastatic tumor cells (Fig 2A). On bone marrow biopsy, hematopoietic cells of all series were seen along with increased plasma cells (Fig 2B, arrowhead) and metastatic deposits of adenocarcinoma (Fig 2B, arrow), which on immunohistochemistry were positive for cytokeratin. Serum protein electrophoresis and immunofixation studies revealed a monoclonal band of immunoglobin G subtype. On flow cytometric immunophenotyping, the plasma cells, as gated by bright expression of CD38 and CD138, were positive for CD56 and lambda light chains and negative for CD19 and kappa light chains (Fig 3). On skeletal survey, there was collapse of D9 and L3 vertebrae with increased uptake in these areas on bone scan. Circumscribed lesion of altered signal intensity in multiple vertebrae with collapse of D9 and L3 vertebrae was seen on magnetic resonance imaging study. Thus, a diagnosis of multiple myeloma (MM) stage IIIA coexistent with stage IV lung adenocarcinoma was made. Patient was offered carboplatin and taxane-based chemotherapy and localized palliative radiotherapy to the spine.