Intracranial granulocytic sarcomaina in a non-leukemia patient

Jing-Feng Wang¹, Peng Sun¹, Dong-Liang Lin², Ming-Chao Fan¹,  
¹ Department of Neurosurgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
² Department of Pathology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China

Correspondence Address:
Ming-Chao Fan
Department of Neurosurgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong
China

Full Text

Sir,

Granulocytic sarcoma (GS), also known as chloroma, is a solid tumor composed of immature myeloid cells at extramedullary sites. [1] The most common sites of GS includes visceral organs, soft tissue, lymph nodes, bone, and skin. [2] The majority of these cases occurred in association with myelogenous leukemia and myeloproliferative disorders. [3],[4],[5],[6] Review of English literature revealed only eight reported cases of GS's involvement with the brain without any evidence of systemic myeloid disease [Table 1]. Here we present the ninth unique case.

A 38-year-old male patient without significant past medical history presented with left lower limb weakness of 2 month's duration and progressive severe headache of 1 week. Computed tomography (CT) scanning showed anirregular high-density occupying lesion in the front oparietal region [Figure 1]a. Magnetic resonance imaging (MRI) routine scanning showed the irregular lesion appeared as isointense on both T1- and T2-weighted images with significant perilesional edema [Figure 1]b and c. Contrast MRI revealed inhomogeneous enhancement and irregular long-T1 lamellar signal [Figure 1]d. Bone marrow biopsyand biochemical tests were normal before and after operation. Total excision of the tumor was performed via right frontoparietal approach. During operation, there was destruction of the skull due to the lesion and hypoderm of the scalp. The lesion was grayish with rich blood supply. Histopathology and immuno his to chemistry confirmed diagnosis of GS [Figure 2]. No complication occurred after the operation. He received systemic chemotherapy in regional hospital after discharge. Clinical and laboratory findings were normal during a 17-month follow-up.{Figure 1}{Figure 2}{Table 1}

Clinically, these tumors occur in all age groups without any sex predilection. About 2-8% of patients who had acute myeloid leukemia (AML) or chronic myeloid leukemia would accompany with GS. [7],[8] The diagnosis of GS is difficult and more than 40% of GS were initially misdiagnosed. [9] The reasons include the rarity of this tumor and most clinicians defect sufficient cognition of it. GS should be considered as a differential diagnosis for any intracranial malignant neoplasm, regardless of evidence of leukemia. Commonly, intracranial GS appear asiso- or hyperdense on brain CT scan. They are usually typically iso-or hyper-intense on T1- and T2-weighted MRI images, and homogeneous enhancement following contrast administration. In order to prevent misdiagnosis, circumstantial histological test is necessary. Basic histopathologic analyses with proper immunohistochemistry staining provide essential information for diagnosis. Immunohistochemically, myeloperoxidase (MPO), CD3, and CD20 are the most useful antibody for GS. MPO is positive for GS, but CD3 (T-cell marker) and CD20 (B-cell marker) are negative. Bone marrow sampling is imperative to assess the absence of AML if a final diagnosis of GS is made.

There is no standard treatment protocol that has been established. The prevailing opinion is that GS with or without bone marrow involvement should be treated as AML because of the high risk of metachronous AML occurrence. Systemic chemotherapy is significantly useful for these patients to have a good long-term survival. Surgical therapy is the only reserved presenting clinical symptom due to mass effect. The long-term prognosis of non-leukemia GS is still despondent.

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