Primary granulocytic sarcoma in the sphenoidal bone and orbit

Spheno-orbital Lesions-A Major Review of Nonmeningioma Causes

PURPOSE

To review the imaging features of the broad range of nonmeningioma lesions of the greater wing of the sphenoid (GWS) bone and adjacent orbit to assist clinicians in differentiating these lesions from each other and from the most common lesion of the GWS and adjacent orbit, meningioma.

METHODS

We reviewed 32 cases of spheno-orbital lesions involving the GWS from our own practice, as well as 109 published cases (total 141), with emphasis on available imaging features on computerized tomography (CT) and MRI. Features that might assist in differentiating meningioma from its mimics were analyzed for each lesion, including the presence of an osteoblastic or hyperostotic response, bone erosion or osteolysis, homogeneous hypo- or hyperintensity on T2-weighted MRI, leptomeningeal involvement, and the absence of a "dural tail" on contrast-enhanced MRI. The clinical and imaging features were also briefly summarized for each diagnostic group.

RESULTS

The largest diagnostic group was metastasis (67 cases, 47.5%). The most useful imaging features that helped differentiate meningioma from its mimics were the presence of bone erosion and the absence of a "dural tail." Other features were helpful in a small minority of cases only. Metastatic prostate cancer was the largest single group (21 cases), and 18 (85.7%) of these were osteoblastic and most closely mimicked meningioma. Prostate cancer patients were generally older than males with GWS meningioma. Almost all other (44/46, or 95.7%) metastatic lesions showed evidence of bone erosion. Almost half (30 of 61, 49.2%) of patients with metastasis presented without a known diagnosis of malignancy. Among children 16 years of age and less, Langerhans cell histiocytosis (10 cases), dermoid cyst (5), and Ewing's sarcoma (5) were the most common diagnoses.

CONCLUSIONS

A combination of a careful history and both CT and MRI gives information, which can best guide the management of patients with spheno-orbital lesions. Metastatic prostate cancer to the GWS most closely mimics GWS meningioma but can in most cases be differentiated on clinical and imaging features. Older males with hyperostotic lesions of the GWS should be investigated for prostate cancer. Other metastatic lesions and primary tumors of the GWS, as well as benign and structural lesions can readily be differentiated from meningioma on clinical and imaging features.

Treatment Outcomes of Intracranial Myeloid Sarcomas: A Meta-Analysis

OBJECTIVE

Intracranial myeloid sarcomas (IMS) are rare central nervous system manifestations of malignant hematopoietic neoplasms of myeloid origin such as acute myeloid leukemia and chronic myeloid leukemia. Reported cases in the literature are limited to primarily case reports. We present a systematic review of this rare central nervous system tumor, characterizing the clinical presentation, tumor location, histopathology, and available treatment modalities. We correlate these variables with mortality, recurrence, and complications to suggest optimal management strategies for IMS.

METHODS

A systematic literature search was performed across Ovid MEDLINE, Scopus, and Embase using 14 search terms in accordance to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. This systematic review examines variables such as patient age, tumor location, size, presenting symptoms, treatment modality, extent of resection, and mortality. We performed descriptive analyses to identify bivariate associations between patient characteristics, treatment, and outcomes.

RESULTS

The mean age at diagnosis was 34.8 years, and the most common etiology was acute myeloid leukemia (68.8%). The most common presenting symptoms were headache (45.5%), vision complaints (27.3%), and weakness/motor symptoms (21.2%). IMS were most commonly located in the temporal lobe (10.1%), cerebellum (10.1%), or falcine/parasagittal (10.1%) region. Patients who received radiotherapy (P < 0.001) or chemotherapy (P < 0.001) had lower rates of mortality versus those who did not. Surgical treatment and extent of resection were not significantly associated with mortality (P > 0.05).

CONCLUSION

The use of adjuvant radiotherapy or chemotherapy for IMS significantly reduces mortality, confirming IMS as a cranial manifestation of a systemic disease. Although surgical treatment is indicated for histopathologic diagnosis and to relieve mass effect, the extent of resection does not predict overall survival.

Isolated Intracranial Myeloid Sarcoma Mimicking Malignant Lymphoma: A Diagnostic Challenge and Literature Reviews

Isolated intracranial myeloid sarcoma (MS) is an unusual variant tumor with few cases reported so far in the medical literature. A 29-year-old woman was admitted to our hospital presenting progressive visual loss in the right eye and weight loss (20 kg) without a previous history of hematological disease (HD). Radiologic evaluation showed the evidence of intracranial mass. Histologically, the resected tumor was composed of a uniform population of primitive cells and primarily misdiagnosed as a T-cell non-Hodgkin’s lymphoma (NHL). Chemotherapy with cyclophosphamide, doxorubicin, vinblastine, and prednisone (CHOP) was ineffective. A biopsy and histopathological evaluation were repeated, and immunohistochemical staining revealed the positivity of immature cells to an extensive panel of myeloid markers. These findings were consistent with a diagnosis of MS and bone marrow infiltration. Literature reviews of previous cases were also undertaken.

Myeloid sarcoma involving the greater wing of the sphenoid bone and additional skeletal sites presenting with unilateral proptosis and fevers

We report a case of myeloid sarcoma with multifocal skeletal involvement, including the greater wing of the sphenoid bone. A 23-month-old boy presented with left-sided proptosis and fevers, and was found to have an infiltrative mass involving the left sphenoid bone on orbital imaging. Full body imaging further demonstrated multiple bony lesions in the pelvis, thoracic and lumbar vertebrae, bilateral femura, and left humerus, and biopsies of the humerus were consistent with myeloid sarcoma. The patient was started on a standard chemotherapy regimen and is responding well. Myeloid sarcoma presenting with proptosis due to sphenoid bone involvement with simultaneous multifocal skeletal involvement is very uncommon and highlights the importance of biopsy for establishing a definitive diagnosis.

Clinicopathological characteristics of extramedullary acute megakaryoblastic leukemia (AMKL): report of a case with initial mastoid presentation and review of literature to compare extramedullary AMKL and non-AMKL cases

Extramedullary acute megakaryoblastic leukemia (AMKL) is a rare neoplasm with a varied clinical presentation. AMKL with initial mastoid presentation has never been reported. The extreme rarity of mastoid AMKL, together with the tendency of extramedullary AMKL to mimic other small blue cell tumors, can create a diagnostic challenge. We report a case of AMKL that initially presented as a mastoid lesion and provide a comprehensive review and analysis that compares the characteristics of extramedullary AMKL and nonmegakaryoblastic acute myeloid leukemia (AML) in reported pediatric cases over the past 30 years. We found that patients with extramedullary AMKL were not only younger than patients without megakaryocytic differentiation but were also limited to those ≤ 2 years of age. In addition, girls predominated in both AMKL and AML MLL(+) groups compared with other types of AML (P  =  0.0366 and P  =  0.0082). Furthermore, we found that extramedullary AMKL was more likely to involve bone than AML MLL(+) (P < 0.0001) or other types of AML (P  =  0.0002). These findings suggest that extramedullary AMKL should be considered in the differential diagnosis of SBCT in children, especially in patients with mastoid or other bony lesions, those ≤ 2 years of age, and female patients.

Extramedullary relapse presenting as trigeminal neuralgia and diplopia after allogeneic hematopoietic stem cell transplantation

A 23-year-old woman presented with trigeminal neuralgia four months after hematopoietic stem cell transplantation (HSCT) for acute myeloblastic leukemia. No leukemic cells were found in the cerebrospinal fluid. Initial brain magnetic resonance imaging (MRI) did not reveal any abnormality. After symptom exacerbation with diplopia, second MRI showed an irregular mass at the right petrous apex, with uniform enhancement and a clear margin which was interpreted as a meningioma. The pathology and immunohistochemistry finally confirmed the diagnosis of granulocytic sarcoma. This case suggests that granulocytic sarcoma should be remembered as a very rare and a malignant pathology in the differential diagnosis of neurologic complications following HSCT.

Myeloid sarcoma presenting with bilateral proptosis and kidney infiltration

The authors describe a male infant with a history of transient pancytopenia who developed progressive bilateral proptosis associated with diffuse infiltration of the kidney and normal bone marrow. The histopathological examination of the kidney revealed diffuse infiltration of cells of myeloid origin with monocytic differentiation. Although orbital involvement by myeloid sarcoma, with or without concurrent acute myeloid leukemia, is well known, there are distinctive features in this patient that are not reported in the literature, namely bilateral proptosis and simultaneous presence of bilateral kidney infiltration, which enabled diagnosis.