Intracranial extramedullary hematopoiesis associated with pilocytic astrocytoma: a case report

Report of a Rare Case of Intracranial Extramedullary Hematopoiesis Mimicking a Brain Tumor

Failure of the bone marrow to maintain adequate blood cell production to match blood metabolic demand incites the production of cell lines outside the bone marrow, which is known as extramedullary hematopoiesis. Herein, we are reporting an 80-year-old male patient who presented with two weeks of worsening headaches and behavioral changes. Labs showed thrombocytosis and imaging showed a large right-sided hemorrhagic brain mass. No evidence of malignancy was seen elsewhere. Brain mass biopsy showed intracranial extramedullary hematopoiesis (IEMH) and bone marrow biopsy confirmed the diagnosis of essential thrombocythemia (ET)/myelofibrosis. This case adds to a few reported cases of IEMH, and to the best of our knowledge, this is the first reported case of IEMH in association with ET. It helps remind clinicians to keep IEMH in the differential diagnosis of those presenting with signs and symptoms of elevated intracranial pressure (ICP) and a newly found brain mass on the background of previously diagnosed or suspected myeloproliferative neoplasms.

Intratumoral Platelets: Harmful or Incidental Bystanders of the Tumor Microenvironment?

Simple Summary

The tumor microenvironment (TME) is the complex and heterogenous ecosystem of solid tumors known to influence their growth and their progression. Besides tumor cells, the TME comprises a variety of host-derived cell types, ranging from endothelial cells to fibroblasts and immune cells. Clinical and experimental data are converging to indicate that platelets, originally known for their fundamental hemostatic function, also participate in tumor development and shaping of the TME. Considering the abundance of antiplatelet drugs, understanding if and how platelets contribute to the TME may lead to new therapeutic tools for improved cancer prevention and treatments.

Abstract

The tumor microenvironment (TME) has gained considerable interest because of its decisive impact on cancer progression, response to treatment, and disease recurrence. The TME can favor the proliferation, dissemination, and immune evasion of cancer cells. Likewise, there is accumulating evidence that intratumoral platelets could favor the development and aggressiveness of solid tumors, notably by influencing tumor cell phenotype and shaping the vascular and immune TME components. Yet, in contrast to other tumor-associated cell types like macrophages and fibroblasts, platelets are still often overlooked as components of the TME. This might be due, in part, to a deficit in investigating and reporting the presence of platelets in the TME and its relationships with cancer characteristics. This review summarizes available evidence from clinical and animal studies supporting the notion that tumor-associated platelets are not incidental bystanders but instead integral and active components of the TME. A particular emphasis is given to the description of intratumoral platelets, as well as to the functional consequences and possible mechanisms of intratumoral platelet accumulation.

Extramedullary hematopoiesis masquerading as a cranial (clivus) tumor

Extramedullary hematopoiesis (EMH) is a well-known phenomenon occurring during fetal development. In the postfetal condition, EMH is commonly associated with hematologic conditions including chronic myeloproliferative or lymphoproliferative disorders, leukemias, and chronic and inherited anemias. We report an unusual location for EMH that masqueraded as a cranial tumor.

Case report of the extramedullary hematopoiesis presented as a hypervascular intracranial mass

Thalassemia is a hematologic disorder that causes ineffective hematopoiesis and is related to severe anemia, iron overload, extramedullary hematopoiesis, and hepatomegaly. Hepatomegaly is related to significant extramedullary hematopoiesis. The other sites that are involved in extramedullary hematopoiesis are spleen, lymph nodes, paraspinal regions, kidney, pleura, and intestine, but intracranial involvement is a rare presentation. We discuss about a case with intracranial medullary hematopoiesis in a thalassemic patient.

Intracranial extramedullary hematopoiesis in beta-thalassemia

Extramedullary hematopoiesis (EMH) represents tumor-like proliferation of hemopoietic tissue which complicates chronic hemoglobinopathy. Intracranial EMH is an extremely rare occurrence. Magnetic resonance imaging (MRI) offers a precise diagnosis. It is essential to distinguish EMH from other extradural central nervous system tumors, because treatment and prognosis are totally different. Herein, we report the imaging findings of beta-thalassemia in a 13-year-old boy complaining of weakness of left side of the body and gait disturbance; CT and MRI revealed an extradural mass in the right temporoparietal region.

Extramedullary hematopoiesis presenting as a compressive cord and cerebral lesion in a patient without a significant hematologic disorder: a case report

INTRODUCTION

Intracranial or spinal compressive lesions due to extramedullary hematopoiesis have been reported in the medical literature. Most of the reported cases are extradural lesions or, on rare occasions, foci within another neoplasm such as hemangioblastoma, meningioma or pilocytic astrocytoma. Often these cases occur in patients with an underlying hematological disorder such as acute myelogenic leukemia, myelofibrosis, or other myelodysplastic syndromes. Such lesions have also been reported in thalassemia major.

CASE PRESENTATION

We report the case of a 43-year-old Iranian woman in whom extramedullary hematopoiesis presented as a compressive cord lesion and then later as an intracranial lesion.

CONCLUSIONS

To the best of our knowledge, we document the first reported case of sacral, lumbar, thoracic and cranial involvement in the same patient with extramedullary hematopoiesis, which seems both rare and remarkable.

Myelolipomatous change in an interhemispheric lipoma associated with corpus callosum agenesis: case report

OBJECTIVE

Interhemisperic lipomas are almost always associated with hypogenesis or agenesis of the corpus callosum. These lesions are stable.

CLINICAL PRESENTATION

We report a case of an interhemispheric lipoma in a 72-year-old man who had undergone myelolipomatous differentiation.

INTERVENTION

Gross total excision of the lesion was performed.

CONCLUSION

Although extremely uncommon, the possibility of myelomatous change should be considered in the differential diagnosis of an intracranial lipoma if it shows some areas of mixed density.

A meningioma with islets of extramedullary myeloid metaplasia: case report

OBJECTIVE

Idiopathic myelofibrosis is a clonal stem cell disorder that leads to ineffective erythropoiesis accompanied by reactive myelofibrosis (bone marrow fibrosis). As a consequence, extramedullary hematopoiesis characteristically develops. The central nervous system is rarely affected; the spinal canal and the cranial meninges are generally the preferred locations. Extramedullary hematopoiesis within central nervous system primary tumors have already been reported but, to our knowledge, never before in a patient with evidence of idiopathic myelofibrosis.

CLINICAL PRESENTATION

A patient experiencing generalized idiopathic myelofibrosis developed a hemorrhagic intracranial meningioma containing islets of extramedullary myeloid metaplasia.

INTERVENTION

The tumor was radically removed through a right frontal craniotomy. After surgery, the patient recovered completely and was discharged with a normal neurological status. After 6 years, the patient is in excellent condition with no sign of recurrence on magnetic resonance imaging scans.

CONCLUSION

The reasons for this uncommon association are uncertain, but we hypothesize that myeloid islets may be involved in the origin of the tumor as well as in its acute hemorrhagic onset. Moreover, we suggest that in the presence of proven idiopathic myelofibrosis intracranial myeloid metaplasia should be ruled out by appropriate neuroimaging and considered as a potential diagnosis in the presence of brain lesions.