Primary extranodal histiocytic sarcoma of lumbar spine

Histiocytic sarcoma mimicking localized tenosynovial giant cell tumor in the pediatric foot: A rare case report with MRI Findings

We present a rare case of histiocytic sarcoma (HS) occurring in the foot of a 12-year-old male, initially misdiagnosed as localized tenosynovial giant cell tumor (TSGCT). HS is an exceptionally uncommon hematologic malignant neoplasm, with its occurrence in children and extranodal sites being even rarer. To our knowledge, this is the first reported case of extranodal HS in the foot, emphasizing comprehensive MRI findings. Initially, the patient was diagnosed with TSGCT based on histological results following surgical resection. However, after recurrence and subsequent surgical resection, histological and immunochemical analyses led to a revised diagnosis of HS. This report focuses on the MRI findings of HS, highlighting the distinctions from localized TSGCT. While both conditions share histopathological similarities, immunohistochemical tests are crucial for accurate diagnosis. The report underscores the importance of differentiating HS for appropriate treatment.

Histiocytic Sarcoma Involving Cervical Vertebra: A Case Report and Review of the Literature

Histiocytic sarcoma (HS) is a rare neoplasm composed of cells with immunohistochemical characteristics of mature histiocytes. It can be disseminated or localized and usually involves the skin, spleen, and gastrointestinal tract. Primary involvement of the vertebral column is extremely rare. We report a 29-year-old female who presented with neck pain and had a destructive 35*43*48 mm lesion in C2 with a paravertebral extension. The initial biopsy did not lead to the correct diagnosis. She later developed dysphagia, and the anterior approach was used for tumor decompression. The diagnosis of cervical histiocytic sarcoma was made, and she underwent radiotherapy. The follow-up MRI showed a marked response to radiotherapy. Here, we report the first case of cervical HS, review all cases of vertebral HS, compare patients’ characteristics and clinical courses, and discuss diagnostic nuances and treatment options.

Histiocytic Sarcoma Arising From a Long Bone: Report of Two Cases

Histiocytic sarcoma is a rare, but aggressive malignant neoplasm of monocyte/macrophage lineage with a wide age distribution. Bone involvement is exceedingly rarer compared to the lymph node, skin, and soft tissue, and no long bone involvement has been reported in the English literature. We here report 2 cases of histiocytic sarcoma involving the long bone: one from the femur of a 77-year-old female, status post the placement of an intramedullary nail for subtrochanteric hip fracture; the other from the radius of a 3-year-old female with no significant medical history. Radiologic imaging showed highly destructive lesions in both cases with soft-tissue extension. Microscopy in both cases showed sheets of polygonal mononuclear cells with abundant eosinophilic cytoplasm, prominent nucleoli, and frequent mitosis. Hemophagocytosis were also identified. Immunohistochemistry showed that the lesional cells were strongly diffusely positive for CD68 and CD163. The first patient deteriorated rapidly, despite the aggressive treatment of amputation and chemotherapy. However, the second patient is disease free 36 months post the treatment of amputation only. We conclude that the long bone could be the primary site of histiocytic sarcoma. Its prognosis could be very variable and it is difficult to predict its behavior based on morphological evaluation only.

Bony Histiocytic Sarcoma of the Scapula: Case Report

Case report of a pediatric patient with a diagnosis of bony histiocytic sarcoma of the scapula, submitted to oncologic resection (Tikhoff-Linberg type II surgery), who returned to previous activities and was disease-free after 24 months of follow-up.

Morphological Distinction of Histiocytic Sarcoma from Other Tumor Types in Bernese Mountain Dogs and Flatcoated Retrievers

BACKGROUND/AIM

Histiocytic sarcoma (HS) represents a group of malignant canine tumors to which Bernese Mountain Dogs (BMD) and Flatcoated Retrievers (FCR) are predisposed. The differential diagnosis for HS is broad, encompassing round cell tumors, sarcomas and other histiocytic diseases. The aim of this study was to establish morphological and immunohistochemical criteria for routine use on formalin-fixed, paraffin-embedded samples and cytological smears for the recognition and differentiation of canine HS and its subtypes.

MATERIALS AND METHODS

Retrospectively, tumor sections were reviewed from 449 BMD and 380 FCR with confirmed or suspected HS, other histiocytic conditions, or a disease of the differential diagnosis of HS.

RESULTS

In a large proportion of cases, 47.5% for histology and for 46.3% cytology, the initial diagnosis was changed after the revision process. A large variation in morphological features of HS was observed in this study, making the existence of several subtypes in dogs also very likely. Furthermore, the different percentage of morphological features between BMD and FCR indicates the different mixture of cell type origins resulting possibly from genetic or environmental differences at the onset of HS in those breeds.

CONCLUSION

This study stresses the value of a strictly applied and standardized scoring system for microscopic evaluation of tumor sections and smears, and the implementation of review and revision of pathological diagnoses.

A rare case of paediatric histiocytic sarcoma of the maxilla and mandible

Histiocytic sarcoma is an extremely rare malignant neoplastic proliferation of the haematopoietic cells. Very few cases have been reported in the paediatric age group. Imaging features have been rarely described in the literature. It can involve any region of the body; however, it most commonly involves the lymph nodes. Its imaging appearance can mimic lymphoproliferative disorders; however, with the advent of new immunohistochemical markers, the diagnosis of HS has become more reliable. We report an unusual case of primary bone involvement by HS with multiple lesions in the facial bones of a 2-year-old female who presented with tooth and mandibular tenderness.

A rare case of primary extranodal, extradural histiocytic sarcoma of the thoracic spine and review of literature

BACKGROUND

Histiocytic sarcoma (HS) is a rare aggressive malignant neoplasm of hematopoietic cell origin showing features of fever, weight loss, adenopathy, hepatosplenomegaly, and pancytopenia. Primary histiocytic sarcoma of spine without involvement of lymph nodes, bone marrow or systemic features is very rare. Due to highly malignant, aggressive behavior and frequent local and distant metastases, prognosis of histocytic sarcoma is poor.

CASE DESCRIPTION

We report a case of primary extranodal variety of histiocytic sarcoma without involvement of bone marrow at extradural location of thoracic spine. Immunohistochemistry panel ruled out other more common lesions in this location. We could not find such presentation of extradural histiocytic sarcoma at the thoracic region in the literature.

CONCLUSION

Primary involvement of extradural space by histiocytic sarcoma could arise from the proliferation of multipotent hematopoietic stem cells which are left in this space embroyologically.

Imaging features of primary extranodal histiocytic sarcoma: report of two cases and a review of the literature

Histiocytic sarcoma is an extremely rare and aggressive malignancy of bone marrow origin that occurs in lymph nodes, skin, and the gastrointestinal tract. We report on the imaging features of two cases of primary histiocytic sarcoma, one in the retroperitoneum causing a tumor-bowel fistula and another with primary bone involvement.