Hidden in the mediastinum: a case of extramedullary hematopoiesis unveiled through thoracoscopy

Extramedullary hematopoiesis (EMH) is a rare condition characterized by proliferation of hematopoietic stem cells outside the bone marrow, usually as a compensatory response to hematological disease. Although EMH primarily occurs in the liver and spleen, it can manifest in atypical locations, such as the mediastinum. We herein describe an asymptomatic 66-year-old man with incidentally discovered posterior mediastinal EMH. A 28- × 32-mm mass was detected during a routine examination. Laboratory findings were within normal limits. Computed tomography revealed a well-defined enhancing mass with a density of 60 Hounsfield units, suggestive of a neurogenic tumor. Surgical resection confirmed EMH, characterized by megakaryocytes and hematopoietic precursors. The patient recovered smoothly and was discharged 5 days postoperatively. Accurate preoperative diagnosis of EMH is challenging, as illustrated by this case. Although typically associated with anemia or hematological abnormalities, EMH can present without such signs. Surgical resection and histopathological examination are essential for diagnosis. This case emphasizes the diagnostic complexity of posterior mediastinal EMH, even in patients without overt hematological disorders. Posterior mediastinal EMH is exceedingly rare and diagnostically demanding. A high index of suspicion and histological tissue analysis are crucial for optimal management. Video-assisted thoracoscopic surgery enables both diagnosis and treatment through mass excision.

Extramedullary hematopoiesis in ribs and severe pulmonary hypertension disease following intermediate beta-thalassemia: a case report

BACKGROUND

Thalassemia is a type of congenital hemoglobinopathy that falls into the category of hemolytic anemias. Extramedullary hematopoiesis is a complication of this disease, which is a mechanism to compensate for chronic anemia in these patients, and imaging is the best diagnostic method.

CASE REPORT

In this report, a 36-year-old Caucasian female patient with intermediate beta thalassemia is presented who, at the time of referral, complained of exacerbated shortness of breath. Imaging showed diffuse expansion masses with soft tissue components in the ribs of both hemithoraxes, leading to the diagnosis of extramedullary hematopoiesis.

CONCLUSION

Extramedullary hematopoiesis in the ribs is an uncommon finding in patients with thalassemia and is a sign of the severity of the disease and a poor prognostic factor that might be preventable if blood transfusion begins at younger ages.

Acute spinal cord compression in the setting of chronic extramedullary hematopoiesis of the thoracic spine

Background

Though rare, pathologic extramedullary hematopoiesis (EMH) can occur in response to myeloproliferative disorders and may present as paravertebral masses.

Case Description

We describe a 63-year-old female with unspecified thalassemia, hemochromatosis, and known asymptomatic extramedullary hematopoiesis of the thoracic spine who acutely developed severe spinal cord compression and a T9 vacuum phenomenon fracture 7 months after her initial diagnosis.

Outcome

The patient was treated with urgent decompression and T9 kyphoplasty, which resulted in complete resolution of her neurological deficits.

Conclusions

The timeline of symptomatology in the case suggests that asymptomatic patients with T-spine extramedullary hematopoiesis can develop progressive neurologic deterioration and atraumatic compression fractures culminating in acute spinal cord injury. While it may be appropriate to treat asymptomatic patients conservatively, surgical decompression must always remain a consideration.

Synergistic immunotherapy targeting cancer-associated anemia: prospects of a combination strategy

Cancer-associated anemia promotes tumor progression, leads to poor quality of life in patients with cancer, and even obstructs the efficacy of immune checkpoint inhibitors therapy. However, the precise mechanism for cancer-associated anemia remains unknown and the feasible strategy to target cancer-associated anemia synergizing immunotherapy needs to be clarified. Here, we review the possible mechanisms of cancer-induced anemia regarding decreased erythropoiesis and increased erythrocyte destruction, and cancer treatment-induced anemia. Moreover, we summarize the current paradigm for cancer-associated anemia treatment. Finally, we propose some prospective paradigms to slow down cancer-associated anemia and synergistic the efficacy of immunotherapy. Video Abstract.

Tumor-host colluding through erythroid progenitor cells: Mechanisms and opportunities

Immunotherapy, particularly immune checkpoint blockade (ICB), has shown great promise in the treatment of cancer and emerged as a beacon of hope for patients who have exhausted traditional therapeutic options. Despite ICB's approval for the treatment of advanced tumors, its efficacy remains limited to a small subset of patients. As a systemic disease, cancer can induce changes in the composition and function of the systemic immune system, and ICB resistance often involves a dialogue between the tumor microenvironment (TME) and the systemic immune macroenvironment. While investigations into tumor progression and ICB resistance have largely focused on the TME itself, the alterations in the systemic immune system and immune macroenvironment are still poorly understood. Given the spleen's role as the largest secondary lymphoid organ, its examination and discussion may provide valuable insights into the systemic immune status and TME components. Recent studies have highlighted the importance of the spleen in tumor progression and immunotherapy, particularly in the context of erythroid progenitor cells (EPCs), a significant cell subpopulation. In this review, we discuss the mechanisms and role of splenic extramedullary hematopoiesis (EMH) as an intermediary in tumor-host interactions and explore the mechanism of EPC-TME collusions. We further summarize the progress in EPC-targeting strategies and emphasize the potential for further research into the role and mechanisms of EPCs in tumor progression and treatment, which could have far-reaching implications.

Paraspinal extramedullary hematopoiesis masquerading as nerve sheath tumor

Paraspinal tumors are uncommon tumors involving the soft-tissue around the vertebrae. The lesion could originate from nerve roots, soft tissue, or blood vessels. The diversity of the lesions poses diagnostic dilemma, warranting robust histopathological diagnosis. We report such a case presenting with radicular pain due to paraspinal extramedullary hematopoiesis (EMH) masquerading as nerve sheath tumor. EMH is presence of hematopoietic tissue outside the bone marrow. EMH is usually seen as a compensatory mechanism associated with underlying hematological disorder. Our case presented primarily as paraspinal mass without underlying hematological disorder on evaluation. Thus, recognizing that EMH can present as paraspinal mass even without a diagnosis of pre-existing hematological disorder is crucial.

Pericardial Extramedullary Hematopoiesis Associated with Metastatic Adenocarcinoma of Gastrointestinal or Pancreaticobiliary Origin: A Case Report

Extramedullary hematopoiesis (EMH) is a rare complication of solid tumor malignancies. We describe the first case of a patient who developed EMH in the pericardium secondary to metastatic gastrointestinal or pancreaticobiliary cancer. A 58-year-old man presented with recurrent episodes of fatigue and shortness of breath and was treated with thoracocentesis and pericardiocentesis for pleural and pericardial effusions, respectively. Owing to a markedly elevated alkaline phosphatase, a bone scan was performed and demonstrated diffuse sclerotic lesions. Evaluation of pleural effusion diagnosed metastatic adenocarcinoma, and cytospin morphology of the pericardial fluid demonstrated EMH. While EMH secondary to solid tumors is commonly suggested to be due to cytokine signaling, we propose the mechanism of EMH in this patient was due to extensive disruption of bone marrow hematopoiesis, similar to what is seen in myeloproliferative neoplasms.

Isolated focal intrahepatic extramedullary hematopoiesis mimicking hepatocellular carcinoma in a cirrhotic patient with secondary hemochromatosis from thalassemia

Extramedullary hematopoiesis is a common complication of ineffective erythropoiesis and bone marrow replacement disorders. Because of its nonspecific presentation and radiological appearance, diagnosing focal intrahepatic extramedullary hematopoiesis is challenging and often misdiagnosed as a hepatic tumor. Herein, we describe the case of a 48-year-old male with thalassemia and AE Bart's disease with secondary hemochromatosis and cirrhosis who developed focal intrahepatic extramedullary hematopoiesis mimicking hepatocellular carcinoma. After hepatic resection, extramedullary hematopoiesis was not observed at any site, including in the remaining liver, at the 4-year follow-up.

Unraveling the interplay between iron homeostasis, ferroptosis and extramedullary hematopoiesis

Iron participates in myriad processes necessary to sustain life. During the past decades, great efforts have been made to understand iron regulation and function in health and disease. Indeed, iron is associated with both physiological (e.g., immune cell biology and function and hematopoiesis) and pathological (e.g., inflammatory and infectious diseases, ferroptosis and ferritinophagy) processes, yet few studies have addressed the potential functional link between iron, the aforementioned processes and extramedullary hematopoiesis, despite the obvious benefits that this could bring to clinical practice. Further investigation in this direction will shape the future development of individualized treatments for iron-linked diseases and chronic inflammatory disorders, including extramedullary hematopoiesis, metabolic syndrome, cardiovascular diseases and cancer.

Magnetic resonance imaging features of intrahepatic extramedullary hematopoiesis: Three case reports

BACKGROUND

Extramedullary hematopoiesis rarely occurs within the liver alone, and is easily misdiagnosed. The radiological literature on this disease is exclusively case reports. There is a paucity of literature on the role of magnetic resonance imaging (MRI). The most common imaging modalities used are computed tomography and ultrasound. This report aims to provide more data on the appearance of extramedullary hematopoiesis using MRI to help radiologists establish the diagnosis.

CASE SUMMARY

Three patients (one male and two females) were incidentally found to have a hepatic mass or nodule, without hepatomegaly or splenomegaly. Laboratory tests including liver function, serum hepatic tumor markers, and hepatitis serologic markers were normal. On MRI scans, all lesions showed lower signal intensity on in-phase images than on out-phase images. One case showed changes in signal intensity on T2 weighted images (WI) and diffusion WI, which shifted from hyperintensity to hypointensity with size enlargement between two rounds of imaging examination. These lesions exhibited different enhancement patterns on dynamic contrast enhancement series.

CONCLUSION

The MRI signal change and in-/out-phase image might provide useful information and help radiologists establish the diagnosis of intrahepatic extramedullary hematopoiesis.

Extramedullary hematopoiesis in an inguinal lymph node: an unusual presentation of primary myelofibrosis

Background

Extramedullary hematopoiesis (EMH) is a proliferation of hematopoietic tissue outside of the bone marrow medullary space. It is a pathophysiologic response, more often associated with either a benign reactive hematological disease or a myeloproliferative neoplasm (MPN). Identification of EMH in adults is always pathologic. It is highly unlikely for a myeloproliferative neoplasm to present with inguinal lymphadenopathy. An unusual and complex case can be precisely diagnosed via a multidisciplinary approach involving experts from various modalities of laboratory. In this regard, the present case highlights the importance of an integrated approach in establishing the diagnosis.

Case presentation

We report a case of a 61-year-old male patient of primary myelofibrosis who presented with extramedullary hematopoiesis in an inguinal lymph node. The patient initially presented with generalized symptoms including anemia, fatigue, abdominal pain, and weight loss. On examination, massive splenomegaly. Chest X-ray revealed consolidation which was secondary to right-sided pleural effusion. Therefore, he was suspected to have a lung carcinoma. However, lymph node biopsy revealed extensive fibrosis, consequently effacing the nodal architecture. An abnormal blood picture raised the possibility of bone marrow infiltration. Extensive panel of markers is tested on lymph node and bone trephine. Cytogenetic studies with G-banding analysis and fluorescence in situ hybridization (FISH) played a significant role in deriving clinical decision. Translocations identified in conventional cytogenetic workup led to the diagnosis of primary myelofibrosis. The case is being reported due to unusual presentation of PMF.

Conclusion

In conclusion, it is a distinctive case of myeloproliferative disorder initially presented with extramedullary hematopoiesis and through multidisciplinary workup successfully diagnosed as primary myelofibrosis. Awareness of unique clinical presentations and integrated approach towards diagnosis is the key to such challenging cases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02660-9.

The Quantification and Significance of Extramedullary Hematopoiesis Seen on Liver Biopsy Specimens

OBJECTIVES

Extramedullary hematopoiesis (EMH) may occur in the liver and is often considered pathologic in adults. Many hematologic and nonhematologic disorders are associated with the development of EMH. However, it is unclear whether the presence of EMH is always pathologic. At present, no formal grading system for EMH in the liver exists.

METHODS

We reviewed 42 liver biopsy specimens with EMH and developed a novel grading system to quantify the degree of EMH from 1 to 3 based on the number of EMH foci in 10 high-power fields.

RESULTS

Most patients had nonhematologic conditions (n = 25). Seventeen patients had a hematologic condition, most frequently a myeloproliferative neoplasm (n = 9). Patients with an underlying hematologic condition had a significantly higher EMH grade compared with those without a hematologic condition (P < .0001). All patients with grade 3 EMH had an underlying hematologic diagnosis, and most (86%) patients with grade 1 EMH had a nonhematologic disorder.

CONCLUSIONS

Our data suggest that EMH grading in the liver is feasible and can identify patients who may have an underlying hematologic condition, which can guide further diagnostic workup.

A Rare Presentation of Extramedullary Hematopoiesis: Perirenal Masses

Extramedullary hematopoiesis (EMH) is a physiological compensatory mechanism that develops in response to ineffective or insufficient hematopoiesis. Although the liver and spleen are the most common sites, EMH may occur anywhere in the body. Peri-renal involvement in EMH is quite rare and mimics tumoral lesions. To our knowledge, 12 peri-renal EMH cases have been reported in the literature so far.  A 57-year woman was admitted to our hospital with non-specific abdominal pain. She had a history of chronic renal failure. On physical examination, diffuse abdominal tenderness and mild rigidity were detected. Blood tests revealed bicytopenia and elevated acute phase reactants. On non-contrast abdominal computed tomography (CT) scan, two peri-renal mass lesions of 4.5 cm and 4 cm were detected incidentally on the right side. Tumoral lesions were considered in the differential diagnosis, and magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT) were performed. Lesions showed mild hypermetabolic activity (SUVmax: 4,68) on PET-CT images. For the definitive diagnosis, an ultrasound-guided core needle biopsy was performed. The histopathological examination was consistent with EMH. This case aims to highlight the peri-renal involvement of EMH, which mimics renal and peri-renal malignancies.

Paravertebral extramedullary hematopoiesis in a case of myelodysplastic syndrome with ring sideroblasts and an SF3B1 mutation

We present the case of a 56-year-old male patient with paravertebral extramedullary hematopoiesis (EMH) secondary to myelodysplastic syndrome with ring sideroblasts and multilineage dysplasia. In a routine health checkup over 5 years prior, he presented with asymptomatic mild anemia and a posterior mediastinal mass. Pathological and cytomorphological findings of the resected paravertebral mass were similar to those of his bone marrow specimen, and included cellularity with erythroid hyperplasia, multilineage dysplastic changes, and the presence of ring sideroblasts. A concordant SF3B1 mutation was detected in both bone marrow and paravertebral mass samples, suggesting that the EMH cells were derived from the bone marrow.

Extramedullary hematopoiesis in myeloproliferative neoplasms: Pathophysiology and treatment strategies

Extramedullary hematopoiesis (EMH) is often a physiologic response to ineffective marrow production of hematologic cells. While this can be found incidentally in various physiologic and pathophysiologic states, the myeloproliferative neoplasms (MPNs) are some of the most common underlying conditions found in patients with EMH. Although this process can assist with hematologic production in defective states, the burden of EMH can lead to symptomatic discomfort and mechanical obstructive complications, most commonly in the spleen and liver. Here we describe the pathophysiology of EMH, treatment options, including medical, surgical and radiation-based approaches.

Extramedullary Hematopoiesis Causing Spinal Cord Compression

Spinal cord compression due to extramedullary hematopoiesis is a rare neurosurgical problem that is successfully treated with urgent decompression. Here we report the case of a young man with hemoglobin Lepore disease and beta thalassemia who presented with 1 month of lower extremity weakness and urinary retention. The patient underwent urgent thoracic laminectomies and recovered fully. This pathology can be treated with multiple modalities; however, decompression must remain in the neurosurgeon's armamentarium in the acute setting.

Invasive methods for the diagnosis and management of intrathoracic extramedullary hematopoiesis: A literature review

BACKGROUND

Extramedullary hematopoiesis is defined as hematopoiesis occurring outside of the bone marrow. It usually compensates insufficient bone marrow function or ineffective erythropoiesis and is observed mostly in hematological disorders. Most common locations of extramedullary hematopoiesis are the spleen, the liver and the lymph nodes. Intrathoracic extramedullary hematopoiesis is rare presenting as bilateral lobulated masses of lower paravertebral regions. This review summarizes the role of invasive techniques in the diagnosis and management of intrathoracic EMH and its complications.

METHODS

An electronic search in PubMed and Google Scholar was conducted with the keywords "intrathoracic extramedullary hematopoiesis" AND "surgery" OR "video-assisted thoracic surgery (VATS)" OR "medical thoracoscopy" OR "biopsy" OR "thoracotomy" OR "image-guided biopsy" OR "median sternotomy", within 1970 to 2020 with the limitation of English language to include those articles reporting data on invasive techniques in intrathoracic extramedullary hematopoiesis.

RESULTS

Overall, 93 articles were originally identified using our search criteria and from the reference list of the previously identified documents. Following elimination of duplicates, 29 were excluded after title, abstract or full text screening, since they did not report the use of invasive techniques in the diagnosis and management of intrathoracic extramedullary hematopoiesis.

CONCLUSIONS

Although in some cases radiological features are typical for the diagnosis of intrathoracic extramedullary hematopoeisis, invasive methods such as bronchoscopy with transbronchial biopsy, ιmage-guided fine needle aspiration, endobronchial ultrasound-guided fine needle aspiration of the mass and mediastinoscopy, medical thoracoscopy, median sternotomy, video-assisted thoracoscopic surgery and thoracotomy, are essential for definite diagnosis and management.

A focal extramedullary hematopoiesis of the spleen in a patient with essential thrombocythemia presenting with a complicated postoperative course: a case report

Background

Extramedullary hematopoiesis is a compensatory response occurring secondary to inadequate bone marrow function and is occasionally observed in essential thrombocythemia (ET). This disease usually presents as multifocal masses in the paravertebral or intra-abdominal region; however, formation of a focal mass in the liver or spleen is rare. In addition, ET is characterized by increased platelet count and shows a tendency toward thrombosis and, occasionally, bleeding. Serious bleeding is common in ET patients, caused by the decrease in or abnormalities of von Willebrand factor (vWF) as a consequence of the precipitous rise in platelets. Therefore, strict management of platelet count using medication is crucial in patients with ET who require invasive procedures, especially splenectomy.

Case presentation

A 68-year-old man with ET was found to have an enlargement of a focal splenic tumor. Imaging findings revealed that the tumor was likely a hemangioma or hamartoma; however, the possibility of malignant disease could not be completely ruled out because of short-term tumor enlargement, and we conducted a splenectomy. The surgery was uneventful, but the patient presented with severe polycythemia and vWF abnormalities postoperatively, which resulted in bleeding from the drain insertion site and wound, epistaxis, and hemorrhoidal bleeding. Three months after discharge, polycythemia still persisted and the level of vWF gradually decreased. With a decrease in vWF, the patient suffered from an increased bleeding tendency. Therefore, the patient has been referred for bone marrow transplantation and is currently awaiting a suitable donor.

Conclusions

Extramedullary hematopoiesis should be listed as a differential diagnosis of focal enlarged splenic tumors, especially in patients with myeloproliferative disorders. Additionally, in splenectomy for ET patients, careful perioperative management taking into consideration the conflicting features of a tendency toward thrombus formation and bleeding is necessary.

Primary Myelofibrosis-Related Renal Disorders Treated with a Janus Kinase Inhibitor

Extramedullary hematopoiesis is widely known to occur in patients with primary myelofibrosis (PMF). Autopsy studies on individuals with PMF revealed that extramedullary hematopoiesis occurred in the kidneys in 35% of the cases, but there is little awareness regarding such lesions. A 63-year-old man was diagnosed with PMF based on a detailed examination of persistent high white blood cells. An examination of the patient's medical records revealed an increased white blood cell count, deterioration of kidney function, and urinary protein excretion developed simultaneously. Thus, a kidney biopsy was performed. Advanced lymphocyte invasion was recognized in the interstitial tissue, and the tubular structure was highly disrupted. Based on these findings, he was diagnosed with interstitial nephritis. However, because of the large number of cells with nuclear atypia in the stroma, additional immunohistochemical staining was also performed, such as glycophorin A, naphthol AS-D, myeloperoxidase, and CD42b. As a result, invasion of three lineages of immature cells, erythroblasts, megakaryocytes, and granulocytes, was identified. Renal dysfunction resulting from interstitial cellular infiltration due to extramedullary hematopoiesis was therefore diagnosed. Treatment with ruxolitinib was initiated after a renal biopsy and the rate of decline in renal function was slightly reduced. Although, in myeloproliferative disorders, proliferative glomerular lesions are widely considered to be renal disorders, there is little awareness regarding interstitial lesions. Extramedullary hematopoiesis of the kidney in PMF is not uncommon, but 40% of cases are reportedly misdiagnosed as interstitial nephritis. Because extramedullary hematopoiesis can be controlled by ruxolitinib, early detection is important.

Myeloid, mast cell, histiocytic and dendritic cell neoplasms and proliferations involving the spleen

Splenic involvement and consequent splenomegaly are usually seen as part of systemic involvement by myeloid neoplasms as well as mast cell and histiocytic neoplasms. Primary splenic involvement by these neoplasms is rare. Splenectomy is usually not performed for establishing a diagnosis of these entities. However, in rare instances, the pathologist may need to evaluate the spleen secondary to splenic rupture or palliative splenectomy to alleviate symptoms related to splenomegaly. This review article describes the clinicopathologic features of a broad group of myeloid, mastocytic, and histiocytic proliferative and neoplastic disorders.

Small lymphocytic lymphoma in true trilineage hematopoietic tissue within heterotopic ossification in an enucleated blind painful eye: a case report

Background

The finding of hematological malignancies within bone marrow in heterotopic ossification has been reported only a handful of times previously in the literature. We described a case of true trilineage hematopoiesis in an excised area of heterotopic ossification from an enucleated blind painful eye.

Case presentation

A 70-year-old Caucasian man, positive for asymptomatic lymphoplasmacytic lymphoma, presented with a blind painful right eye in our ophthalmology department to evaluate enucleation bulbi. After enucleation, a histopathologic examination revealed the presence of intertrabecular infiltration in the metaplastic bone marrow of non-Hodgkin B lymphoma, with small lymphocytes, with similar characteristics to the already known disease.

Conclusion

This uncommon case reveals the possibility of the localization of malignant cells within bone metaplasia of intraocular ossification in an enucleated blind painful eye. From a practical point of view, a careful systematic histopathological examination of all resected tissues in patients with a history of malignant neoplastic pathology is necessary to confirm the diagnosis and exclude occult malignancies.

Extramedullary hematopoiesis causing spinal cord compression with excellent durable response after radiation therapy: Case report and review of the literature

Extramedullary hematopoiesis (EMH) is a rare occurrence in the setting of spinal cord compression. We report on a 72-year-old who was initially diagnosed with polycythemia vera (PV) which after approximately 15 years converted to myelofibrosis which confirmed on bone marrow biopsy. In 2016, he presented to our ED with clinical symptoms suggested of spinal cord compression at the T3–8 region. This was confirmed by MRI imaging. After a review of existing literature, it was elected to treat the affected area with radiation consisting of 15 fractions of 200 cGy. Within 10 days, the patient had begun to regain strength in the affected regions both motor and sensory. At the 2 month follow-up, he was symptom-free and imaging also showed a complete response. In January 2019, the patient again presented with clinical symptoms of spinal cord compression in the T10–12 area. Again, this was confirmed by MRI imaging. The same fractionation scheme was used and again the patient had a complete resolution of all symptoms both motor and sensory at the 1-month follow-up. Of interest is that during both the courses of treatment there was not a significant in any blood indices from baseline presentation. In the setting of EMH-causing cord compression, the use of radiation is warranted with excellent early response that appears durable. In addition, we present a review of the literature on this topic.

Myeloid diseases in the lung and pleura

Myeloid diseases detected as primary or secondary lesions in the lung and pleura are rare. Clinical presentations and radiographic results may vary significantly depending on the nature of the diseases. The most common diseases associated with lung and pleura involvement are myeloid sarcoma/acute myeloid leukemia (AML) and extramedullary hematopoiesis (EMH). AML typically represents localized involvement by systemic acute leukemia, while EMH is frequently secondary to underlying benign hematolymphoid disorders or myeloproliferative neoplasms. This review provides an overview of the pathogenesis, clinical presentations, radiologic/imaging studies, pathologic and genetic findings, and treatment/outcomes associated with myeloid diseases in the lung and pleura.

A rare case of extramedullary hematopoiesis in adrenal mass

Extramedullary hematopoiesis (EMH) is a compensatory mechanism for deficient formation or function of red blood cells. Very rarely, extramedullary hematopoiesis is finding out in the kidneys as well as adrenals. We present a 50 year old man, who was admitted in the Urology Department with symptoms of renal colic. A contrast enhanced computed tomography (CT) of the abdomen and pelvis revealed right adrenal lesion of 80/79 mm in coronary size. The final diagnosis was myelolipoma of the right adrenal gland. We presented a rare case of adrenal tumor mass in patient without any haemotological disease that requires surgical excision.

A case report of a rare omental extramedullary hematopoiesis in an adult: 'an idiopathic finding'

This is a case of a 62-year-old female, known to have multiple medical problems, who presented to her primary care physician with an intermittent abdominal pain and discomfort for a few months. The initial work-up showed mild leucocytosis and a small mass in the omentum. Given that the most concerning differential diagnosis was malignancy, the patient was referred to oncology, where biopsy of the mass showed omentum extramedullary hematopoiesis. The differential diagnosis was wide; however, a repeat computed tomography (CT) scan of the abdomen and pelvis did show persistence of the omental mass. After ruling out any possible causes, including myelofibrosis, with a normal bone marrow, her extramedullary hematopoiesis was deemed of unknown origin and with no clear explanation. Therefore, the patient was diagnosed with a rare adult idiopathic omental extramedullary hematopoiesis that was stable over time.

Injectable, scalable 3D tissue-engineered model of marrow hematopoiesis

Modeling the interaction between the supportive stroma and the hematopoietic stem and progenitor cells (HSPC) is of high interest in the regeneration of the bone marrow niche in blood disorders. In this work, we present an injectable co-culture system to study this interaction in a coherent in vitro culture and in vivo transplantation model. We assemble a 3D hematopoietic niche in vitro by co-culture of supportive OP9 mesenchymal cells and HSPCs in porous, chemically defined collagen-coated carboxymethylcellulose microscaffolds (CCMs). Flow cytometry and hematopoietic colony forming assays demonstrate the stromal supportive capacity for in vitro hematopoiesis in the absence of exogenous cytokines. After in vitro culture, we recover a paste-like living injectable niche biomaterial from CCM co-cultures by controlled, partial dehydration. Cell viability and the association between stroma and HSPCs are maintained in this process. After subcutaneous injection of this living artificial niche in vivo, we find maintenance of stromal and hematopoietic populations over 12 weeks in immunodeficient mice. Indeed, vascularization is enhanced in the presence of HSPCs. Our approach provides a minimalistic, scalable, biomimetic in vitro model of hematopoiesis in a microcarrier format that preserves the HSPC progenitor function, while being injectable in vivo without disrupting the cell-cell interactions established in vitro.

Alpha fetoprotein (AFP) participates in the build up of hematopoietic cells in the early embryonic stage: an abortion case observation

Background

At the 3rd week of human embryo, some cell clumps are formed by the hyperplasia of mesenchymal cells at the germ layer of the yolk sac wall. These cell clumps are known as blood islands. The cells in the center of the blood islands further develop into primitive blood cells, such as hematopoietic stem cells. The blood island in the yolk sac further develops into the extramedullary hematopoietic tissue in 1 week at the 3rd to 4th week.

Case presentation

A 32-year-old pregnant woman who missed menstruation for 42 days discovered that her pregnancy required an abortion. The tissue collected after the abortion was a piece of gray-yellow and villus-like intrauterine tissue of a size of approximately 4 cm × 3 cm × 1.3 cm. The paraffin section stained with hematoxylin and eosin and observed under the light microscope showed a visible small embryo tissue in the early placental tissue. In the embryonic tissue, a large amount of extramedullary hematopoietic tissue was present, including myeloid, erythroid and megakaryocytic cells. The extramedullary hematopoietic cells were located in the blood vessels or naive liver sinus, were positive for alpha fetoprotein (AFP) and were without lymphocytes. The erythrocytes consisted of a large number of nucleated red blood cells. In addition, a neural tube and cystic structure were found. The final pathological diagnosis was as follows: Early embryonic tissue with a cystic structure formation in the embryo. After medical abortion the pregnant woman recovered well, without complications.

Conclusions

Our case illustrates that AFP is an important structural protein of nucleated erythrocytes and myeloid hematopoietic cells, suggesting that it may participate in the build up of nucleated erythrocytes and myeloid hematopoietic cells. Furthermore, our case suggests that nucleated red blood cells can be detected from the 42nd day of pregnancy by a peripheral blood sample from the mother.

Extramedullary hematopoiesis of the sphenoid sinus associated with hereditary spherocytosis: A case report

Extramedullary hematopoiesis is a rare cause of a sinonasal mass that presents unique diagnostic and treatment challenges. While there are numerous reports of patients with hereditary spherocytosis developing extramedullary hematopoiesis in the posterior mediastinum, involvement in the paranasal sinuses has not previously been described. Here, we present the first case of a patient with hereditary spherocytosis developing extramedullary hematopoiesis in the sphenoid sinus.

Splenic myeloid metaplasia in warm autoimmune hemolytic anemia (wAIHA): a retrospective study

Background

Splenic myeloid metaplasia (SMM) is a kind of extramedullary hematopoiesis, whereas its clinical significance in wAIHA remains unclear. The aim of this study is evaluating the frequency and clinical characteristics of SMM, compared with splenic-congestion (SC).

Methods

We included patients with wAIHA treated in a Mexican tertiary hospital between January 1992 and December 2015. All patients received steroids as first-line treatment and splenectomy as second-line treatment.

Results

Among the thirty-six splenectomized patients, 15 (41.6%) and 21 (58.4%) were diagnosed as SMM and SC, respectively. No differences were found in clinical characteristics between two groups. SMM patients showed lower platelet count (147×10⁹/L vs. 240×10⁹/L, P=0.02) and higher presence of anti-dsDNA antibodies (40% vs. 4.7%, P=0.01) than SC patients. Although the complete response (CR) rate with first-line treatment was lower in SMM patients (13.3% vs. 47.6%; P=0.04), post-splenectomy median disease-free-survival (DFS) was longer (16.2 mo vs. 5.1 mo; P=0.19). Univariate/multivariate analysis showed that achieving CR during first-line treatment (OR 0.3, 95% CI: 0.03–0.94, P=0.03) and higher platelet count (OR 0.99, 95% CI: 0.98–0.99, P=0.03) were protective factors for SMM; and anti-dsDNA titer higher than 9.6 IU/dL was a risk factor for SMM (OR 2.76, 95% CI: 1.48–5.14, P<0.001).

Conclusion

The wAIHA patients with SMM have different biological profiles with those without SMM. This study is the first trial evaluating the significance of histopathological spleen findings and their association with rheumatologic profile.

An insolite occurrence during splenectomy for myelofibrosis

INTRODUCTION

Primary myelofibrosis (MF) is a myeloproliferative neoplasm that results in debilitating constitutional symptoms, splenomegaly, and cytopenias. In patients with symptomatic splenomegaly, splenectomy remains a viable treatment option for MF patients with medically refractory symptomatic splenomegaly that precludes the use of ruxolitinib.

CASE PRESENTATION

We present the clinical case of a patient who was admitted to our Department to perform a splenectomy in MF as a therapeutic step prior to an allogeneic stem cell transplantation (ASCT). A laparotomic splenectomy and excision of whitish wide-spread peritoneal and omental nodulations was performed. There were no operative complications and the surgery was completed with minimal blood loss. The histopathological exam revealed an extramedullary hematopoiesis in both spleen and peritoneal nodules.

CONCLUSION

In primary myelofibrosis it must always be kept in mind the possible presence of peritoneal implants of extramedullary hematopoiesis and ascites of reactive genesis. We report a rare case of peritoneal carcinomatosis-like implants of extramedullary hematopoiesis found at splenectomy for MF.

A case of perirenal extramedullary hematopoiesis in a patient with primary myelofibrosis

Extramedullary hematopoiesis (EMH) is hematopoiesis in organs outside the bone marrow and most frequently occurs in the liver, spleen, and lymph nodes. We report a case of perirenal EMH revealed by kidney biopsy in a patient with primary myelofibrosis. We observed only bilateral kidney enlargement with plain computed tomography (CT) and ultrasonography before obtaining a renal biopsy. We obtained a percutaneous biopsy from the lower pole of the left kidney using ultrasonographic guidance. Ultrasonography just after the renal biopsy revealed no bleeding around the kidney. However, early the next morning, the patient developed severe hemorrhagic shock. Contrast-enhanced CT at that time revealed a massive hematoma in the left posterior perirenal space and bilateral abnormalities of the perirenal soft tissues. In patients with primary myelofibrosis, if plain CT shows an abnormal renal enlargement, EMH should be considered. In addition, a contrast-enhanced CT should be obtained before performing a percutaneous renal biopsy to assess for the possibility of perirenal EMH in these patients.

An unusual presentation of primary myelofibrosis

Extramedullary hematopoisis (EMH) normally occurs in fetal life, but it is pathological in later life and most of the time because of underlying marrow diseases. Sometimes EMH tissue can present with large masses which can cause compressive and constitutional symptoms. They can be wrongly diagnosed as malignancy and pulmonary tuberculosis. Here in this case report we are reporting a case with mediastinal EMH because of underlying mylofibrosis.

Temporal bone extramedullary hematopoiesis as a causeof pediatric bilateral conductive hearing loss:Case report and review of the literature

Extramedullary hematopoiesis occurs in children with hemoglobinopathy and chronic anemia. The liver and spleen are often affected first, but other foci can develop to support erythrocyte demand. We report a case of a nine-year-old with beta thalassemia and temporal bone extramedullary hematopoiesis causing ossicular fixation and bilateral conductive hearing loss. There is only one case in the literature describing this phenomenon in pediatric patients, and this is the first case report of bilateral hearing loss from this physiologic phenomenon. Otolaryngologists should consider this etiology in patients with chronic anemia and conductive hearing loss in the absence of otitis media.

Presence of the IVS-I-6-Mutated Allele in Beta-Thalassemia Major Patients Correlates with Extramedullary Hematopoiesis Incidence

Extramedullary hematopoiesis (EMH) results from the extension of hematopoietic tissue beyond the confines of the bones. Since the initiation of regular transfusion programs from an early age for all thalassemia major (ΤΜ) patients, EMH has not been considered a clinical issue anymore. The present study aims to record the prevalence of EMH in chronically transfused ΤΜ patients followed at our institution and to investigate possible risk factors associated with its occurrence. The project was designed as a retrospective, nonexperimental, descriptive, exploratory study. In total, the study enrolled 104 patients. EMH was revealed in 15/104 (14%) patients. The presence of intravening sequence (IVS)-I-6 was significantly related with the development of EMH (p < 0.05). No other demographic or biological factor studied was found to be related with the presence of EMH. The study stresses a profound incidence of asymptomatic EMH in a solid group of well-transfused ΤΜ patients. Given the high incidence of the IVS-I-6 allele in the Mediterranean and Middle Eastern region, high-quality, prospective, multicenter studies could confirm the association of EMH occurrence with the presence of the IVS-I-6 mutation and further evaluate the exact role of this mutation in the EMH process.

Clinical management of the homozygous α-thalassemia with unusual mandibular manifestation of hematopoiesis

Alpha (α)-thalassemias are the most common genetic disorder of hemoglobin (Hb) synthesis, affecting up to 5% of the world's population. These congenital hemolytic anemias induce extramedullary hematopoiesis, including the liver, spleen, sinuses, and the diploic spaces of the skull. Oral health problems in patients with thalassemias are mostly related to a varied degree of facial deformities, malocclusions, and/or dental arch dimensions. We present a case with a 49-year-old man, diagnosed with homozygous α thalassemia that came to the Faculty of Dentistry at the University of Murcia for a dental treatment. It was observed that the patient had an unusual mandibular manifestation of hematopoiesis.

Nitrogen-containing bisphosphonate induces a newly discovered hematopoietic structure in the omentum of an anemic mouse model by stimulating G-CSF production

We previously reported that the injection of nitrogen-containing bisphosphonate (NBP) induced the site of erythropoiesis to shift from the bone marrow (BM) to the spleen. Our previous study established a severely anemic mouse model that was treated with a combination of NBP with phenylhydrazine (PHZ), which induced newly discovered hematopoietic organs in the omentum. No reports have shown that new hematopoietic organs form under any condition. We characterized the structures and factors related to the formation of these new organs. Splenectomized mice were treated with NBP to inhibit erythropoiesis in the BM and then injected with PHZ to induce hemolytic anemia. The mice showed severe anemia and wine-colored structures appeared in the omentum. Some hematopoietic cells, including megakaryocytes, and well-developed sinuses were observed in these structures. Numerous TER119-positive erythroblasts were located with cells positive for PCNA, a cell proliferation marker. C-kit-positive cells were detected and mRNAs related to hematopoiesis were expressed in these structures. Moreover, TER119-positive erythroblasts emerged and formed clusters and hematopoiesis-related factors were detected in the omentum of mice treated with NBP and PHZ. The levels of G-CSF in the serum and hematopoietic progenitor cells (HPCs) in the peripheral blood were increased upon treatment with both NBP and PHZ. These results suggest that the induced hematopoietic structures act as the sites of erythropoiesis and that NBP-induced G-CSF production causes HPC mobilization, homing and colonization in the omentum because they constitutively express some factors, including SDF-1; thus, the newly discovered hematopoietic structure in this study might be formed.

The Innate Immune Response in Myocardial Infarction, Repair, and Regeneration

Following myocardial infarction (MI), resident innate immune cells such as macrophages, innate lymphoid cells, and mast cells rapidly coordinate their function to contain inflammation by removing dying cells and promoting cardiomyocyte replenishment. To sustain local tissue repair functions, hematopoietic progenitors are mobilized from the bone marrow to the spleen to generate subsequent myeloid cells such as monocytes and neutrophils, which are rapidly recruited at the site of MI. A finely tuned balance between local adaptation and recruitment controls the overall outcome of the cardiac tissue regeneration versus repair and scar formation.In this chapter, the (potential) roles of the innate immune system residing in the heart are discussed in the context of recent findings about macrophage ontogeny and their homeostasis with circulating monocytes during cardiac tissue growth and after myocardial infarction. Their interactions with other members of the innate immune system are also discussed with a particular emphasis on the potential involvement of mast cells and innate lymphoid cells during MI, largely underestimated until recently. Understanding the development and the functions of the different protagonists responding to MI as well as their potential cross talk could help design new strategies for regenerative medicine intervention.

Assessment of sites of marrow and extramedullary hematopoiesis by hybrid imaging in primary myelofibrosis patients

We investigated noninvasive procedures by hybrid imaging to assess the sites of active or inactive hematopoiesis in patients with primary myelofibrosis (PMF). To this end, we used two radionuclides, technetium 99m ((99m) Tc) and indium 111-chloride ((111) In-Cl3 ), coupled with single-photon emission tomography/computed tomography (SPECT/CT). We studied five patients with PMF and one with secondary myelofibrosis (MF). The classical pattern of lower fixation of both tracers at the axial skeleton where the myelofibrotic process occurs and the reactivation of sites of active hematopoiesis at the distal skeleton were confirmed. Coupling both radionuclides to SPECT/CT imaging allowed for more precise visualization of the sites of extramedullary hematopoiesis as those observed in the spleen and liver. Splenic high uptake of (111) In-Cl3 coupled with SPECT/CT represents a pathognomonic feature of PMF. We conclude that, the hybrid imaging procedures that we studied might constitute an alternative noninvasive method for the screening of the whole-body marrow and, by this way, to assess the impact of targeted therapies in PMF patients in whom it is well known that the distribution of the hematopoietic active areas is disturbed. Hybrid imaging could also be useful for diagnostic purposes in cases of early PMF or in suspected cases of myelofibrosis secondary to polycythemia vera or essential thrombocythemia.

Spinal Cord Compression Secondary to Extramedullary Hematopoiesis: Case Report and Review of the Literature

Extramedullary hematopoiesis (EMH) is a rare cause of spinal cord compression (SCC). EMH represents the growth of blood cells outside of the bone marrow and occurs in a variety of hematologic illnesses, including various types of anemia and myeloproliferative disorders. Although EMH usually occurs in the liver, spleen, and lymph nodes, it may also occur within the spinal canal. When this occurs, the mass effect can compress the spinal cord, potentially leading to the development of neurological deficits. We present a case of SCC secondary to EMH. This report illustrates the importance of considering EMH in the differential diagnosis of SCC, even in the absence of signs of its most common etiologies.

Cortical bone invasion in non-transfusion-dependent thalassemia: tumefactive extramedullary hematopoiesis reviewed

OBJECTIVE OF THE STUDY

To assess the prevalence of cortical bone invasion (CBI) with secondary extramedullary hematopoiesis (EMH) in patients with non-transfusion-dependent thalassemia (NTDT), to determine its predilection sites on thoracic and abdominal imaging, to determine whether there is an association between various clinical and hematological parameters, and to evaluate its various findings mainly on magnetic resonance imaging (MRI), in addition to computed tomography (CT) scans.

MATERIALS AND METHODS

This is a retrospective cohort study of 57 patients with NTDT imaged by CT or MRI. Both clinical and laboratory data were gathered. An imaging scoring system was used to describe the appearance of CBI by MRI.

RESULTS

Twenty-seven patients (47.4 %) were found to have CBI and EMH with the most common location being the thoracic spine. Splenectomy and lower hemoglobin level were found to be independent risk factors for its development. Most lesions were homogenous (70 %), had predominant red marrow signal (67 %), and well-defined margins (89 %).

CONCLUSION

CBI and secondary tumefactive EMH are common findings in patients with NTDT, with distinct imaging and clinical characteristics. An increased risk was seen in patients with splenectomy and lower hemoglobin. The imaging scoring system described is helpful in diagnosing and describing this entity, hence precluding unnecessary biopsies.

P-Selectin Sustains Extramedullary Hematopoiesis in the Gata1 low Model of Myelofibrosis

Splenomegaly is a major manifestation of primary myelofibrosis (PMF) contributing to clinical symptoms and hematologic abnormalities. The spleen from PMF patients contains increased numbers of hematopoietic stem cells (HSC) and megakaryocytes (MK). These MK express high levels of P-selectin (P-sel) that, by triggering neutrophil emperipolesis, may cause TGF-β release and disease progression. This hypothesis was tested by deleting the P-sel gene in the myelofibrosis mouse model carrying the hypomorphic Gata1(low) mutation that induces megakaryocyte abnormalities that recapitulate those observed in PMF. P-sel(null) Gata1(low) mice survived splenectomy and lived 3 months longer than P-sel(WT) Gata1(low) littermates and expressed limited fibrosis and osteosclerosis in the marrow or splenomegaly. Furthermore, deletion of P-sel disrupted megakaryocyte/neutrophil interactions in spleen, reduced TGF-β content, and corrected the HSC distribution that in Gata1(low) mice, as in PMF patients, is abnormally expanded in spleen. Conversely, pharmacological inhibition of TGF-β reduced P-sel expression in MK and corrected HSC distribution. Spleens, but not marrow, of Gata1(low) mice contained numerous cKIT(pos) activated fibrocytes, probably of dendritic cell origin, whose membrane protrusions interacted with MK establishing niches hosting immature cKIT(pos) hematopoietic cells. These activated fibrocytes were not detected in spleens from P-sel(null) Gata1(low) or TGF-β-inhibited Gata1(low) littermates and were observed in spleen, but not in marrow, from PMF patients. Therefore, in Gata1(low) mice, and possibly in PMF, abnormal P-sel expression in MK may mediate the pathological cell interactions that increase TGF-β content in MK and favor establishment of a microenvironment that supports myelofibrosis-related HSC in spleen.

[Symptomatic extramedullary haematopoiesis in β-thalassemia: A retrospective single centre study]

INTRODUCTION

Symptomatic extramedullary hematopoiesis (EH) is a rare but potentially severe phenomenon which occurs in β-thalassemia. There are no treatment guidelines.

METHODS

Retrospective single centre study including the cases of symptomatic EH encountered between 1997 and 2014 in a unit specialised in red blood cell genetic disorders. Description of clinical, biological and radiological characteristics of the patients, treatments received, and outcomes.

RESULTS

Among 182 β-thalassemia patients followed during the study period, 7 cases of symptomatic EH were diagnosed. They were 5 men and 2 women, and their mean age was 37 years. Four patients were splenectomised, two patients were regularly transfused, and four patients had already received erythropoietin. EH was localised in intravertebral areas and responsible for dorsal spinal cord compression in 5 patients, in paravertebral dorsal area in 1 patient, and in presacral area in 1 patient. The mean hemoglobin level at diagnosis was 7.9 g/dL. Treatment administered included: red cell transfusion in 6 cases, associated with hydroxyurea in 5 cases and/or radiotherapy in 3 patients. One patient was treated with surgery and HU. After a median follow-up of 41 months, clinical recovery was complete in 2 patients and partial in 5 patients.

CONCLUSION

EH must be suspected in β-thalassemia in patients presenting clinical signs of organ compression, and a typical radiological aspect. The functional prognosis depends on the rapidity of treatment, which includes red blood cell transfusion, hydroxyurea, radiotherapy, and rarely surgery. Long-term outcome is uncertain.

Role of SDF-1 (CXCL12) in regulating hematopoietic stem and progenitor cells traffic into the liver during extramedullary hematopoiesis induced by G-CSF, AMD3100 and PHZ

The stromal cell derived factor 1 (SDF-1/CXCL12) plays an essential role in the homing of hematopoietic stem and progenitor cells (HSPCs) to bone marrow (BM). It is not known whether SDF-1 may also regulate the homing of HSPCs to the liver during extramedullary hematopoiesis (EMH). Here, we investigated the possible role of SDF-1 in attracting HSPCs to the liver during experimental EMH induced by the hematopoietic mobilizers G-CSF, AMD3100 and phenylhydrazine (PHZ). Mice treated with G-CSF, AMD3100 and PHZ showed a significant increase in the expression of SDF-1 in the liver sinusoidal endothelial cells (LSECs) microenvironments. Liver from mice treated with the hematopoietic mobilizers showed HSPCs located adjacent to the LSEC microenvironments, expressing high levels of SDF-1. An inverse relationship was found between the hepatic SDF-1 levels and those in the BM. In vitro, LSEC monolayers induced the migration of HSPCs, and this effect was significantly reduced by AMD3100. In conclusion, our results provide the first evidence showing that SDF-1 expressed by LSEC can be a major player in the recruitment of HSPCs to the liver during EMH induced by hematopoietic mobilizers.

A Rare Presentation of Extramedullary Hematopoiesis in Post-polycythemic Myelofibrosis

Polycythemia vera is a clonal proliferative disorder of the bone marrow that could possibly evolve into myelofibrosis in its natural course. Progression to myelofibrosis is usually a late stage complication and presents clinically with refractory cytopenias and extramedullary hematopoiesis (EMH). EMH can occur in any tissue during the course of post-polycythemic myelofibrosis. However, skin and cardiac involvements seems to be very rare. We present a 56-year-old woman with post-polycythemic myelofibrosis refractory to treatment, developing EMH after splenectomy in various organs, exceptionally the skin and the heart. Along with the case, the clinical presentations, treatment options, prognostic significance of EMH and the role of cytogenetics is discussed in the light of the literature.

Intestinal obstruction caused by extramedullary hematopoiesis and ascites in primary myelofibrosis

Primary myelofibrosis (PMF) is a clonal hematopoietic stem cell disorder. It is characterized by bone marrow fibrosis, extramedullary hematopoiesis with hepatosplenomegaly and leukoerythroblastosis in the peripheral blood. The main clinical manifestations of PMF are anemia, bleeding, hepatosplenomegaly, fatigue, and fever. Here we report a rare case of PMF with anemia, small bowel obstruction and ascites due to extramedullary hematopoiesis and portal hypertension. The diagnosis was difficult to establish before surgery and the differential diagnosis is discussed.

Thoracic cord compression by extramedullary hematopoiesis in thalassemia

Extramedullary hematopoiesis (EMH) refers to hematopoiesis occurring outside the medulla of bone. It may be physiologic or due to pathological conditions like hematopoietic disorders. EMH can involve liver, spleen, thorax, and lymph nodes. It can involve paraspinal tissues with extension and involvement of spinal canal. In our case, the diagnosis was confirmed by the history of the patient stating underlying hematological condition and by magnetic resonance imaging (MRI) findings showing large soft tissue masses in paraspinal areas with involvement of spinal canal and leading to cord compression.

Maxillofacial extramedullary hematopoiesis in a child with sickle cell presenting as bilateral periorbital cellulitis

Review of a case of paraosseous extramedullary hematopoiesis (EMH) affecting the maxillary sinuses and retro-orbital spaces imitating bilateral orbital cellulitis. Maxillofacial EMH causes diagnostic/therapeutic challenges. This case report describes a 4-year-old African American male with sickle cell disease (HbSS) who presented with bilateral orbitofacial swelling. Diagnosis was made with imaging and confirmed with tissue sampling. Partial exchange transfusion was utilized to stop the progression of maxillofacial EMH and to treat the patient's chronic anemia. Follow-up MRI showed regression of orbital and retro-orbital involvement. Early treatment with conservative modalities and close observation may prevent need for more invasive treatments.