Spinal intramedullary granulocytic sarcoma: magnetic resonance imaging

Unusual presentations of central nervous system myeloid sarcoma

Myeloid sarcoma (MS), also termed 'chloroma' or 'granulocytic sarcoma', is a tumour mass consisting of myeloid blasts occurring at an anatomical site other than the bone marrow. MS occurs in up to 8% of patients with acute myeloid leukaemia. While MS typically involves the skin or lymph nodes, almost any tissue can be affected, and symptoms largely depend on the organ involved and subsequent mass effect. We present a case series of patients that presented to a tertiary hospital with MS affecting the central nervous system over a 4-month period. These three cases demonstrate the vast spectrum of clinical presentations of MS and, furthermore, show rare examples of intramedullary spinal cord involvement and disseminated intraparenchymal brain disease.

Myeloid Sarcoma

Hematological malignancies can manifest as extramedullary soft tissue masses in relatively rare cases. The rarity of it causes a diagnostic and therapeutic challenge. One of the rarest manifestations is myeloid sarcoma (MS). MS develops as part of acute myeloid leukemia, myeloproliferative neoplasm, or myelodysplastic syndrome or at relapse, especially following allogeneic hematopoietic stem cell transplant. The tumor displays high myeloperoxidase expression, hence the color green, and is called chloroma. It most commonly appears in lymph nodes, skin and soft tissues, bone, testes, gastrointestinal tract, and peritoneum. Immunohistochemistry shows CD68-KP1 as the most commonly expressed marker, then myeloperoxidase, CD117, CD99, CD68/PG-M1, lysozyme, CD34, terminal deoxynucleotidyl transferase, CD56, CD61, CD30, glycophorin A, and CD4. Different chromosomal abnormalities including MLL rearrangement, t(8; 21), monosomy 7, trisomy 8, trisomy 11, trisomy 4, inversion (16), monosomy 16,16q deletion, 5q deletion, and 20q deletion were reported. Most of the literature about MS are case reports and small retrospective studies, thus there is limited clinical knowledge of the cases and their presentation and management plans. Here, we provide a review of what has been reported in the literature about MS in the light of our experiences.

Isolated granulocytic sarcoma of the nasopharynx: a case report and review of the literature

Granulocytic sarcoma (GS) is a rare extramedullary manifestation of acute myeloid leukemia (AML). It may also represent blastic transformation of myelodysplastic syndromes or myeloproliferative neoplasms. Although usually seen in the context of advanced and poorly controlled disease, it may also present as the first manifestation of illness, without concurrent bone marrow or blood involvement. In the medical literature, chloroma and GS are terms that have been used interchangeably with myeloid sarcoma. GS usually manifests as soft tissue or bony masses in several extracranial sites, such as bone, periosteum, and lymph nodes; involvement of the head and neck region is uncommon. We report a case of a woman with insidious onset of progressive nasal congestion and diminished hearing who was diagnosed with an isolated GS of the nasopharynx. With involved field radiotherapy, she achieved a complete remission of 12-months duration before being diagnosed with overt AML. She has remained disease-free for greater than 18 months following induction and consolidation chemotherapy. Through a MEDLINE®/PubMed® search we identified an additional 13 cases of nasopharyngeal GS. The median age was 37 years (range 1 to 81 years). The cases were equally distributed among the sexes. The most common presenting symptoms were conductive hearing loss and sinonasal congestion. Isolated GS was identified in six cases, and the median time from diagnosis of GS to AML was 12 months (range 3 to 48 months). The treatment varied, but responses were seen in all the patients who received chemotherapy with or without radiotherapy.

Low back pain and lumbar radiculopathy as harbingers of acute myeloid leukemia recurrence in a patient with myeloid sarcoma

Myeloid sarcoma (MS) is an extra-osseous, solid collection of myeloblasts. It is associated with myeloid leukemias, and rarely affects the spine. The most common clinical presentation of MS in spine patients is some form of pain related to compression of neural elements. Given that MS is rare, and its imaging characteristics are similar to other more common diagnoses, it is frequently missed on initial presentation. We present a 28-year-old female, in her fifth year of remission from AML, with low back pain and right lumbar radiculopathy. Initially, the leading diagnosis was schwannoma in preference to neurofibroma; however, intra-operative pathology and subsequent bone marrow biopsy revealed the tumor to be MS. This report highlights the difficulties of diagnosis of MS in patients in remission from acute myeloid leukemia. Thus, in patients with a history of leukemia, MS should be considered in the differential diagnosis of any epidural or nerve root tumor. Timely diagnosis and treatment are key to optimal outcomes.

How I treat extramedullary acute myeloid leukemia

Extramedullary (EM) manifestations of acute leukemia include a wide variety of clinically significant phenomena that often pose therapeutic dilemmas. Myeloid sarcoma (MS) and leukemia cutis (LC) represent 2 well-known EM manifestations with a range of clinical presentations. MS (also known as granulocytic sarcoma or chloroma) is a rare EM tumor of immature myeloid cells. LC specifically refers to the infiltration of the epidermis, dermis, or subcutis by neoplastic leukocytes (leukemia cells), resulting in clinically identifiable cutaneous lesions. The molecular mechanisms underlying EM involvement are not well defined, but recent immunophenotyping, cytogenetic, and molecular analysis are beginning to provide some understanding. Certain cytogenetic abnormalities are associated with increased risk of EM involvement, potentially through altering tissue-homing pathways. The prognostic significance of EM involvement is not fully understood. Therefore, it has been difficult to define the optimal treatment of patients with MS or LC. The timing of EM development at presentation versus relapse, involvement of the marrow, and AML risk classification help to determine our approach to treatment of EM disease.

Granulocytic sarcoma of the spine: MRI and clinical review

OBJECTIVE

Granulocytic sarcoma is a tumor formed by myeloid precursors at an extramedullary site. The purpose of this study was to evaluate the MRI findings and clinical manifestations in 32 cases of granulocytic sarcoma of the spine.

MATERIALS AND METHODS

Thirty-two patients (21 males, 11 females; mean age, 32 years) with myeloid leukemia and spinal granulocytic sarcoma were included in this study. All of the patients underwent radiotherapy with chemotherapy, and four patients underwent surgical decompression or excisional biopsy. All 32 patients underwent MRI of the spine; 21 patients underwent follow-up MRI.

RESULTS

Nine patients had spinal granulocytic sarcoma in the initial manifestation of leukemia. The other 23 diagnoses were made during a remission or relapse period. The lumbosacral and thoracic portions of the spine were commonly involved. Twenty-seven patients had multiple or contiguous multilevel involvement. According to location, spinal granulocytic sarcoma was classified as epidural in the central spinal canal, epidural along the nerve course, thickening of the nerve root itself, or prevertebral. Lesions were seen as isointense on T1-weighted images and had intermediate signal intensity with homogeneous enhancement on T2-weighted images. Nine patients had complete reduction of the tumor volume, and 12 patients had partial reduction. The median survival period was 9 months, and the 1-year survival rate was 41%.

CONCLUSION

Knowledge of the imaging findings of spinal granulocytic sarcoma, which consists of multiple extramedullary masses with diffuse leukemic bone marrow infiltration, can lead to early diagnosis and appropriate treatment to reduce neurologic symptoms.

Granulocytic sarcoma: an unusual complication of aleukemic myeloid leukemia causing spinal cord compression. A case report and literature review

Granulocytic sarcoma (chloroma) is a rare solid tumor resulting from the proliferation of myelogenous leukemia cells. Chloromas usually present as soft tissue or bony masses of the head and neck in patients with acute myelogenous leukemia (AML) of the French-American-British M2 subtype. Occasionally chloromas may occur in patients with myelodysplasia and other myeloproliferative disorders and rarely precede the development of systemic disease. It is distinctly rare for such tumors to cause epidural compression as a first manifestation of disease. Herein, we report the case of a man with a thoracic extradural chloroma whose presentation of progressive lumbar pain ultimately led to the diagnosis of M2 AML. Surgical intervention prior to the onset of paraplegia and the prompt initiation of chemotherapy resulted in an excellent neurological and hematological outcome. We also review the literature of previously reported cases of spinal cord-associated chloroma and focus on the clinical presentation and treatment of this disorder.

Isolated Recurrence of Granulocytic Sarcoma Manifesting as Extra- and Intracranial Masses

A 30-year-old female presented with a rare case of isolated recurrence of granulocytic sarcoma manifesting as extra- and intracranial masses 16 months after successful treatment of acute myeloblastic leukemia (M-2). She presented with a swelling located on her forehead that had appeared just after hitting her forehead, and never diminished in size. The mass was elastic hard and not freely mobile. Computed tomography and magnetic resonance imaging demonstrated enhanced masses in the right frontal extra- and intracranial region with no bone destruction. There was no evidence of relapse in the bone marrow. Needle aspiration biopsy of the subscalpal mass was performed. Fluorescence in situ hybridization revealed AML1/MTG8 fusion gene associated with t(8; 21). Two courses of systemic chemotherapy with high-dose cytarabine and total neural axis irradiation resulted in complete remission.

Multiple granulocytic sarcomas in acute myeloblastic leukemia with simultaneous occurrence of t(8:21) and trisomy 8

This report describes a rare case of multiple intracranial, extradural chloromas. A five year old African American male presented with headache, fever, and vomiting. The peripheral blood smear showed myeloblasts with Auer rods. The CTscan of the brain showed three intracranial, epidural lesions as well as soft tissue masses in the retroorbital region and sphenoid sinuses. CTscan of the chest showed two paraspinal epidural thoracic masses. Pathology of the epidural intracranial mass revealed a granulocytic sarcoma. Cytogenetic analysis showed simultaneous occurrence of t(8;21) and trisomy 8. Following induction therapy, he is now in complete remission.

Hemangioblastomas and other uncommon intramedullary tumors

Astrocytoma and ependymoma make up 90% of intramedullary tumors between them. However, a host of less common tumors form the remaining 10%: these include hemangioblastomas, subependymomas, gangliogliomas and other neuronal variants, metastases from extraneural cancers, and a host of other lesions that typically occur intracranially but which present on rare occasions in the intramedullary location. Most neurosurgeons will encounter the unusual tumors of the spinal cord described in this review only a few times during their professional careers, but it is nevertheless important to recognize the distinct radiological and intraoperative features of those for which significant series of patients have been accumulated. Metastases and germinomas aside, the other neoplasms described here are relatively benign in their clinical and histological behavior, and can be meaningfully resected by careful microsurgical technique.