Jebmh.com Original Article J. Evid. Based Med. Healthc., pISSN- 2349-2562, eISSN- 2349-2570/ Vol. 3/Issue 34/Apr. 28, 2016 Page 1656 MYELOID SARCOMA – A CLINICOPATHOLOGICAL ANALYSIS OF 25 CASES Usha Amirtham 1 , Shankaranand Siddappa Bharatnur 2 , Shanthi Velusamy 3 , Mangalagowri Mayanna 4 , Prasanna Kumari 5 , Lakshmaiah Chinnagiriyappa Kuntegowdanahalli 6 , Rekha Vijaykumar 7 1 Associate Professor, Department of Pathology, Kidwai Memorial Institute of Oncology, Bangalore, India. 2 Assistant Professor, Department of Pathology, Kidwai Memorial Institute of Oncology, Bangalore, India. 3 Fellow in Oncopathology, Department of Pathology, Kidwai Memorial Institute of Oncology, Bangalore, India. 4 Assistant Professor, Department of Pathology, Cytogenetic Unit, Kidwai Memorial Institute of Oncology, Bangalore, India. 5 Associate Professor, Department of Pathology, Cytogenetic Unit, Kidwai Memorial Institute of Oncology, Bangalore, India. 6 Professor, Department of Medical Oncology, Kidwai Memorial Institute of Oncology, Bangalore, India. 7 Professor, Department of Pathology, Kidwai Memorial Institute of Oncology, Bangalore, India. ABSTRACT INTRODUCTION Myeloid sarcoma (MS) is defined as “a tumour mass consisting of myeloid blasts with or without maturation, occurring at an anatomical site other than bone marrow”. It rarely arises as the only lesion, referred to as primary myeloid sarcoma. Secondary myeloid sarcomas precede or develop concomitantly with acute myeloid leukaemia (AML), myelodysplastic syndrome (MDS), myeloproliferative neoplasm (MPN) or MDS/MPN. MS developing in a known patient of AML is considered as relapse irrespective of blood and bone marrow findings. This study retrospectively analyses the clinicopathological, morphological and immunohistochemical profiles along with available data on cytogenetics and followup of 25 patients diagnosed as myeloid sarcoma in a regional cancer centre in South India. MATERIALS AND METHODS All cases diagnosed histopathologically as myeloid sarcoma between 2006 and 2015 were retrieved from the archives of the department of pathology. The clinicopathological profile of these cases was reviewed, including age, sex, site of involvement and accompanying haematological findings. Immunohistochemical and cytogenetic findings were noted along with laboratory data and median survival time. RESULTS Of the 25 cases studied, 18 patients were male and 7 patients were female. The age ranged from 14 months to 65 years. The commonest site of involvement was lymph node followed by bone, skin and soft tissue. Twenty cases represented primary MS and the remaining five cases were secondary myeloid sarcomas. Of the latter, four cases were associated with AML and one with chronic myeloid leukaemia (CML). One case of primary lesion in the radius subsequently developed another lesion in calcaneum after 3 years. Trisomy 8 was the commonest cytogenetic abnormality seen. Two patients of the series are alive and on treatment whereas 7 patients died within a year of diagnosis and the remaining were lost to followup. CONCLUSION Myeloid sarcoma is a rare disease with a higher incidence in males. It was seen more commonly as an isolated lesion in our study involving the lymph nodes. It requires early diagnosis and appropriate management including bone marrow transplantation, considering the high mortality. KEYWORDS Blastic transformation, Cytogenetics, Lymph node, Myeloid sarcoma. HOW TO CITE THIS ARTICLE: Amirtham U, Bharatnur SS, Velusamy S, et al. Myeloid sarcoma – a clinicopathological analysis of 25 cases. J. Evid. Based Med. Healthc. 2016; 3(34), 1656-1660. DOI: 10.18410/jebmh/2016/370 INTRODUCTION: First described by Burns 1 in 1811, myeloid sarcoma was termed chloroma by King et al 2 to describe the green colour of the tumour on exposure to air due to the enzyme myeloperoxidase. It is synonymous with extramedullary myeloid tumour and granulocytic sarcoma. The skin, lymph node, gastrointestinal tract, bone, soft tissue and testis are the most frequently involved sites, 3,4 though the tumour may arise at any site. Rarer sites reported include heart, spinal cord and liver. 5,6-9 The tumour has the morphological features of a round cell tumour with definitive diagnosis necessitating immunohistochemistry. Early and accurate diagnosis is necessary to provide appropriate treatment which includes chemotherapy and bone marrow transplantation. Financial or Other, Competing Interest: None. Submission 24-03-2016, Peer Review 11-04-2016, Acceptance 18-04-2016, Published 28-04-2016. Corresponding Author: Dr. Shanthi Velusamy, Fellow in Oncopathology, Department of Pathology, Kidwai Memorial Institute of Oncology, Dr. M. H. Mari Gowda Road, Hombe Gowda Nagar, Bengaluru-560030. E-mail: shanz84@gmail.com DOI: 10.18410/jebmh/2016/370