Gujarat Cancer Society Research Journal Monoblastic Sarcoma / Myeloid Sarcoma of Paraspinal Region Presenting as Acute Paraparesis in Aleukemic Patient- A Rare Case Report from Western India

Kikani Alpeshkumar1, Modi Mitul1*, Panchal Harsha2, Trivedi Priti2*, Lakum Nirmal1#, Parikh Sonia2, Makadia Gautam1: Resident1, Professor2 Department of Medical and Pediatric *Department of Pathology #Department of Radiology

Summary spine screening. Ultrasonography of pelvis suggested Myeloid sarcoma (MS), also known as extramedullary large well defined hypoechoic lesion measuring 45 acute myeloid , extramedullary myeloid tumor, and granulocytic sarcoma, myeloblastoma or chloroma, is a rare mm×30 mm in subcutaneous tissue and musculature manifestation which is characterized by the occurrence of 1 or in anterior abdominal wall, possibility of metastatic more tumor myeloid masses occurring at an extramedullary site. deposit , of which was suggestive of malignant We are reporting a rare case of monoblastic sarcoma in a 50 year round cell tumor. MRI of spine revealed altered signal male patient without history of acute with involvement of paraspinal region, abdominal wall and tongue, intensity lesion in intraduralextramedullary who presented with acute paraparesis. The patient was treated compartment extending from D3 to D7 level in post with decompression laminectomy followed by Radiotherapy. contrast T1 weighted SAG images (Figure 1) and in After confirming diagnosis of monoblastic sarcoma, patient was T2 weighted images showed altered signal intensity treated with regimen to (hyperintense) lesion in intraduralextramedullary control systemic disease, but outcome was poor. Keywords: Myeloid sarcoma, Monoblastic sarcoma compartment at D3 level (Figure 2). There were ,Granulocytic sarcoma , Myeloblastoma, Compressive multiple other similarly enhancing lesions seen along myelopathy visualized posterior aspects of ribs and posterior elements of the other distal dorsal vertebrae and Introduction adjacent soft tissue, possibility of metastases. On Myeloid sarcoma (MS) is a rare malignant presentation at GCRI, patient had complete condition comprising of immature myeloid cells and paraplegia with bladder dysfunction. On physical developing at an extramedullary site that most examination patient was having macroglossia, right commonly involves the bone, skin, or , 1 iliac lump and paraspinal mass, bilateral complete although any part of the body may be affected. MS paraplegia (power grade 0) with bowel bladder may develop de novo or simultaneously with acute involvement. Patient was posted for decompression myeloid leukemia (AML), myeloproliferative D6/D7 laminectomy. (MPN), or Surgical pathology report was suggestive of (MDS). MS may be the first manifestation of AML, Monoblastic sarcomas (MBLS) composed of a large precede it by months or years, or equally represent the population (> 80%) of monoblasts. The neoplastic initial manifestation of relapse in a previously treated 2,3 cells were large, with abundant eosinophilic AML in remission. The incidence of myeloid cytoplasm, round or oval nuclei with dispersed sarcoma in the course of acute myeloid leukaemia has chromatin and one or more prominent nucleoli. been reported to range from 3-4.7%. The occurrence Promonocytes showed more irregular, delicately of extra-medullary lesions before the onset of overt 4 convoluted nuclear features. disease is rare. Here we are reporting a case of was done to confirm the diagnosis which was positive monoblastic sarcoma in a patient without overt for LCA, CD43 (strong positive), CD 117, vimentin, myeloid leukemia. Bcl2, CD79a (weak positive) and negative for CD2, CD3, CD10, CD20, CD19, CD21, Bcl6, CD1a, S100, Case Report EMA, CD23, CD30, CD13. CD 99 was diffuse A 50 year male presented with gradual onset stained. MIB 1 was 80%. From this IHC panels of both lower limb weakness over two month which diagnosis of monoblastic sarcoma/ myeloid sarcoma progressed to complete paralysis of both lower limb was confirmed. There were no blasts in peripheral with urinary incontinence. At the same time patient smear and aspiration and biopsy was had noted lump in right iliac region. Initially patient done which was normocellular and uninvolved by any consulted local who evaluated patient with primary or secondary malignancy. Patient was treated USG pelvis and MRI dorso-lumbar spine with whole with post operative radiotherapy to spine D6/D7

38 Volume 18 Number 2 October 2016 Gujarat Cancer Society Research Journal region with 30G in 10 fractions. Radiotherapy was not the neoplastic tissue usually appears firm with a given to tongue and chest wall because they were fish-flesh appearance. FDG PETCT is negative in 10 asymptomatic. Patient was referred to medical % cases in myeloid sarcoma. oncology department for further management. Microscopically monoblastic sarcomas are Patient was advised PET CT which was suggestive of composed of a large population (>80%) of non avid soft tissue density lesion in costal pleura, few monoblasts. The neoplastic cells are large, with peritoneal nodules and subcutaneous nodules anterior abundant eosinophilic cytoplasm, round or oval to urinary bladder. There was no FDG avid disease nuclei with dispersed chromatin and one or more anywhere in body. Biopsy of the tongue was done prominent nucleoli. Promonocytes show more which revealed same pathology as in paraspinal mass. irregular, delicately convoluted nuclear features. On As such myeloid sarcoma is chemotherapy sensitive immunohistochemistry , Monoblastic sarcomas are disease so patient was treated with chemotherapy. strongly positive for CD43, lysozyme, CD68, CD163, Patient was started for 5+2 induction with weakly for CD4, and negative for CD34.5 daunorubicin and cytarabine but expired due to The WHO Classification of tumours; sudden cardiac arrest after one day of chemotherapy, pathology and genetics of tumours of the cause of cardiac arrest was not found. hematopoietic and lymphoid tissues6 recognizes monoblastic sarcomas as less common variants that Discussion is composed of monoblasts and associated with Myeloid sarcomas were first described in acute monoblastic leukemia and also tumors with the early 19th century. They were initially bilineage or trilineage hematopoiesis, predominant described as "chloroma" due to their greenish e r y t h r o i d p r e c u r s o r s o r p r e d o m i n a n t external appearance. This is a because of the megakaryocytes that may occur in conjunction presence of enzymes in the with transformation of a CMPD, but isolated MS premature myeloid cells. Later on many cases of without overt leukemia is very rare.6 chloroma were described that were not green and Giemsa or Wright/Giemsa stains on had the gross features of a sarcoma, so the imprints are the best way to see the morphology terminology was changed to " granulocytic of the blasts. Cytochemical stains such as a sarcoma". As we now know that not all myeloid positive sudan black or myeloperoxidase stain are are derived from , the helpful if touch imprints are available to identify preferred term is "myeloid sarcoma". The clinical the myeloid lineage. The definitive diagnosis presentation of myeloid sarcoma varies and is today is usually based on immunohistochemistry. 5,9 dependent on the site of involvement. Commonly The best immunohistochemical stains used for this involved sites of occurrence include subperiosteal include MPO and lysozyme. MPO immunostain is bone structures of the skull, paranasal sinuses, positive in most myeloblastic variants (as well as sternum, ribs, vertebrae and pelvis; lymph nodes in some cells myelomonocytic variants) while and skin are also common sites.4 Rare sites lysozyme is frequently expressed in monoblastic reported in the literature include the pancreas, variants. Megakaryoblastic cells are characterized heart, brain, mouth, breast, gastrointestinal and by the expression of factor VIII, CD 61, and CD biliary tract, prostate, urinary bladder and 318 while Glycophorin C and/or blood group gynecologic tract and more.6 A single tumor or proteins occur in the rare erythroblastic variant. A sometimes multiple nodular masses of various variable percentage of non-differentiated blasts sizes may occur. Myeloid sarcomas may be found may be positive for CD13, CD33, CD 34, CD117 in one of four settings: 1. In patients with known (cKit), or CD99.8 Sometimes expression of acute myeloid leukemia (AML) in the active aberrant markers such as B-cell-, T-cell-, or NK- phase of the disease. 2. In patients with a chronic associated antigens including CD30 may be seen. myeloproliferative disorder (CMPD) or a Positivity of tumor cells for CD43, a T-cell marker, myelodysplastic syndrome (MDS), in whom without coexpression of CD3 should always myeloid sarcoma may be the first manifestation prompt consideration of a myeloid tumor and not of blastic transformation. 3. As the first be misinterpreted as a neoplasm of T-cell lineage. manifestation of relapse in patients previously The use of only four antibodies (MPO, CD68, treated for primary or secondary acute leukemia. Lysozyme and CD34) has been proposed to 4. De novo in healthy subjects, in whom a typical distinguish the more common variants of myeloid form of AML may occur after an interval of sarcomas.9 A study of 30 cases showed CD117 weeks, months or even years.4,7 Rarely no reactivity in 87%, MPO, 97%; lysozyme, 93%; leukemia develops. No age group is immune; CD34, 47%; CD45, 84%; CD43, 97%; TdT, 37%; however, some reports suggest that two thirds of CD79a, 20%; CD20, 10%; CD3, 10%; and CD10, the cases occur before the age of 15 years. Grossly 1% .10

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The correct diagnosis of myeloid sarcoma treatment with allogeneic bone marrow is important so appropriate therapy can be transplantation. Int J Hematol. 2004;80:186-189 instituted. While the diagnosis is often thought of 4. Breccia M, Mandelli F, Petti MC, et al: Clinico- in patients with an established history of AML, pathological characteristics of myeloid sarcoma MDS or a CMPD, in other patients the diagnosis is at diagnosis and during follow-up: report of 12 often missed. The differential diagnosis is lengthy cases from a single institution. Leuk Res and includes non-Hodgkin (including 2004;28:116-1159 precursor B- or Tcell, Burkitt, some peripheral 5. Borislav A, Wenle W, Yi Ning, et al: Myeloid NK/T-cell and diffuse large B-cell ), sarcomas: a histologic, immunohistochemical, small round cell tumors (including neuroblastoma, and cytogenetic study.Diagnostic Pathology rhabdomyosarcoma, Ewing's sarcoma, peripheral 2007, 2:42 doi:10.1186/1746-1596-2-42 neuroectodermal tumor and medulloblastoma), 6. Running R.D, Bennett J, Matutes E, et al: undifferentiated carcinoma or melanoma, malignant Acute myeloid leukemia not otherwise and malignant with categorised In: Jaffe E.S, Harris N.L, Stein H, atypical mast cells. Extramedullary localizations of and Vardiman J.W (eds). WHO Classification chronic myeloproliferative diseases without blast of Tumours; Pathology and Genetics of crisis should also be differentiated from myeloid Tumours of Haematopoietic and Lymphoid sarcoma. Immunohistochemistry may aid Tissues. IARC Press, Lyon 2001:pages 104- distinguish myeloid sarcoma from malignant 105 lymphoma, however the coexpression of some T- 7. Audouin J, Comperat E, Le Tourneau A, cell markers and staining with TdT and CD 34 Camilleri-Broet S, Adida C, Molina T, Diebold can cause difficulties in interpretation. Treatment is J: Myeloid sarcoma: clinical and morphologic similar to that for AML, even in cases of isolated criteria useful for diagnosis. Int J SurgPathol. tumors with no blood or bone marrow 2003; 1:1 271-282 involvement. 11 Radiotherapy has been proposed in 8. Zhang PJ, Barcos M, Stewart CC, Block AW, association with chemotherapy for patients with Sait S, Brooks JJ: Immunoreactivity of MIC2 massive tumors or for patients with (CD99) in acute myelogenous leukemia and compression. related disease. Mod Pathol 2000; 13:452-458. In patients with AML the progression of 9. Chang CC, Eshoa C, Kampalath B, Shidham myeloid sarcoma has the same prognosis as the VB, Perkins S: Immunophenotypic profile of underlying leukemia. Patients with an AML myeloid cells in granulocytic sarcoma by associated with a t(8;21) and presenting myeloid immunohistochemistry. Correlation with blast sarcoma have a low rate of complete remission, differentiation in bone marrow. Am J Clin and overall survival is poor.12 This appears to be Pathol 2000; 114:807-811 in contrast to the better prognosis generally seen 10. Chen J, Yanuck R, Abbondanzo S et al: c-Kit in AML with t(8; 21). In patients with CMPD and (CD117) Reactivity in Extramedullary Myeloid MDS myeloid sarcoma defines a blastic Tumor/Granulocytic Sarcoma. Archives of transformation often associated with a short Pathology and Laboratory Medicine 2001; survival. 125; 1448-1452 11. Byrd JC, Edenfield WJ, Shields DJ, Dawson References: NA: Extramedullary myeloid cell tumors in 1. Pileri SA, Ascani S, Cox MC, et al: Myeloid acute nonlymphocytic leukemia: a clinical sarcoma: clinico-pathologic, phenotypic and review. J Clin Oncol. 1995; 13:1800-1816 cytogenetic analysis of 92 adult patients. 12. Byrd JC, Weiss RB, Arthur DC, Lawrence D, Leukemia. 2007;21:340-350 Baer MR, Davey F, Trikha ES, Carroll AJ, 2. Hancock JC, Prchal JT, Bennett JM, et al: Tantravahi R, Qumsiyeh M, Patil SR, Moore Trilineageextramedullary myeloid cell tumor in JO, Mayer RJ, Schiffer CA, Bloomfield CD: myelodysplastic syndrome. Arch Pathol Lab Extramedullary leukemia adversely affects Med. 1997;121:520-523 hematologic complete remission rate and 3. Imamura T, Matsuo S, Yoshihara T, et al: overall survival in patients with Granulocytic sarcoma presenting with severe t(8;21)(q22;q22): Results from Cancer and adenopathy (cervical lymph nodes, tonsils, and Leukemia Group B 8461. J Clin Oncol 1997; a d e n o i d s ) i n a c h i l d w i t h j u v e n i l e 15:466-475 myelomonocytic leukemia and successful

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