Beware of Bone Marrow: Incidental Detection and Primary Diagnosis of Solid Tumours in Bone Marrow Aspiration and Biopsies; A Study of 22 Cases

Background & objective: Introduction: First detection of any solid tumour as metastatic deposits in bone marrow directs clinicians to start searching for the primary tumour. Detection of bone marrow metastasis determines the stage of the malignancy, prognosis, mode of treatment, chemotherapeutic response and followup in case of relapse. The aim of the current study was to analyse the clinicohaematological presentation and morphological pattern of infiltration of solid tumours detected first as metastatic deposits on bone marrow examination. Methods: Three-year retrospective analysis of MGG-stained bone marrow aspiration smears and touch imprints of the bone marrow biopsy and Hematoxylin and Eosin (H&E) stained histopathological sections of biopsies was performed at the Department of Pathology at a tertiary care institute (January 2014 to December 2016). The morphological pattern of metastatic deposits and haematological profiles of the patients were analysed. Exclusion criterion was the presence of hematolymphoid malignancies. Results: In 22 cases, bone marrow was the first site of detection of metastasis. The age of the patients ranged from 3 years and 10 months to 82 years, with equal gender predilection. Overall, 16 cases had cytopenias, 9 cases each had leucocytosis and leukoerythroblastic presentation. The metastasis was from Ewing’s sarcoma, prostate carcinoma, gastric adenocarcinoma invasive duct carcinoma breast, gallbladder carcinoma, lacrimal duct carcinoma and invasive papillary urothelial carcinoma. Conclusions: Bone marrow examination is a cheap and reliable investigation to detect metastasis in an unsuspecting case. Bilateral trephine biopsies are recommended to increase the efficacy of detecting bone marrow metastasis.