Os - Bone


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  M 7 ans , tumeur du fémur, biopsie chirurgicale M 7 yo, tumor of the femur, surgical biopsy.  




Lesion metaphysaire, atteignant le cartilage de conjugaison.

Lesion of metaphysis, reaching the cartilaginous plate


Os cortical soufflé

Cortical bone thinned

Presence d'images kystiques, avec des niveaux.

Presence of cystic lesions, with level pattern.



Deux specimens biopsiques soumis

Two biopsies submitted

Espaces enfractueux, hematiques, et cellularité pléomorphe avec mitoses atypiques.

Irregular cystic spaces and pleomorphic cellular pattern with atypical mitotic figures.

Foyer de formation d'ostéoide et dé maturation osseuse avec figure de mitose.

Foci of osteoid and bone formation, with mitotic figures.

Foyers de production d'osteoide atypique

Atypical osteoid production

Diagnostic proposé :

Proposed Diagnosis:









Ostéosarcome télangiectasique









Telangiectatic osteosarcoma



Telangiectatic osteosarcoma
(Ref. Diagnostic Histopathology of Tumors, CDM Fletcher, Churchill Livingstone, 2nd Ed.)

Telangiectatic osteosarcoma forms approximately 4% of all osteosarcomas in the Mayo Clinic files. There is controversy in the literature concerning the importance of differentiating telangiectatic osteosarcoma from conventional osteosarcoma. Part of this controversy relates to the different criteria used to make the diagnosis in different institutions. The criteria that we use are as follows:

1. The roentgenogram shows a purely lytic destructive lesion, usually in the metaphysis of a long bone of a young patient.
2. The gross appearance is that of a cavity separated by septa or a cavity containing a blood clot.
3. Microscopically, there are septa separating spaces and simulating the appearance of an aneurysmal bone cyst. However, the lining cells are pleomorphic. Bone production by the tumor cells is minimal.

We do not include osteosarcomas that are partly telangiectatic in this group. In the original study from the Mayo Clinic, it was thought that telangiectatic osteosarcoma was associated with an extremely poor prognosis. However, a series from Memorial Hospital suggested that the prognosis for telangiectatic osteosarcoma is the same as for conventional osteosarcoma. A later study from the Mayo Clinic found that the prognosis for more recent patients with telangiectatic osteosarcoma is the same as for those who have conventional osteosarcoma. This did not seem to be associated with the use of chemotherapy; however, in our experience, telangiectatic osteosarcoma is extremely chemosensitive.

We believe that telangiectatic osteosarcoma should still be retained as a separate entity because of the characteristic gross and microscopic features. Most importantly, it helps to remind us of the possibility of telangiectatic osteosarcoma when an aneurysmal bone cyst is diagnosed. Aneurysmal bone cysts and telangiectatic osteosarcomas resemble each other in many respects, including roentgenographic, gross, and low power microscopic features. The only difference is the presence of markedly atypical cells in the septa of telangiectatic osteosarcoma.



Some abstracts about Telangiectatic Osteosarcoma


Radiology. 2003 Nov;229(2):545-53. Epub 2003 Sep 25.

Telangiectatic osteosarcoma: radiologic-pathologic comparison.

Murphey MD, wan Jaovisidha S, Temple HT, Gannon FH, Jelinek JS, Malawer MM.

Department of Radiologic Pathology, Armed Forces Institute of Pathology, 6825
16th Street NW, Bldg 54, Rm M127A, Washington, DC 20306, USA.

PURPOSE: To describe the imaging characteristics of a large series of
telangiectatic osteosarcomas with pathologic findings for comparison.

MATERIALS AND METHODS: The authors retrospectively reviewed 40 pathologically confirmed telangiectatic osteosarcomas. Patient demographics and images from radiography (n = 36), bone scintigraphy (n = 17), angiography (n = 4), computed tomography (CT) (n = 25), and magnetic resonance (MR) imaging (n = 27) were evaluated by three authors in consensus for lesion location, size, and intrinsic characteristics. There were 27 men (68%) and 13 women (32%) in the study, with an age range of 4-83 years (mean age, 24 years).

RESULTS: Lesions frequently affected the femur, tibia, and humerus. Radiographs showed geographic bone lysis, a wide zone of transition, and matrix mineralization. CT demonstrated low attenuation, MR demonstrated high signal intensity on T2-weighted images, and both demonstrated hemorrhage, which simulated the appearance of aneurysmal bone cyst. Viable sarcomatous tissue surrounding hemorrhagic and/or necrotic regions was best seen at contrast material-enhanced CT and MR imaging, with thick peripheral, septal, and nodular enhancement in all cases. Subtle matrix mineralization in this viable tissue was best seen at CT. An associated soft-tissue mass was also seen in 19 of 25 cases (76%) at CT and in 24 of 27 cases (89%) at MR imaging.

CONCLUSION: CT and MR imaging findings of telangiectatic osteosarcoma often include thick nodular tissue (and matrix mineralization at CT) in a largely hemorrhagic and/or necrotic osseous lesion with an associated soft-tissue mass, which allows distinction from aneurysmal bone cyst.

Cancer. 2003 Jun 15;97(12):3068-75.

Neoadjuvant chemotherapy for high-grade central osteosarcoma of the extremity.
Histologic response to preoperative chemotherapy correlates with histologic
subtype of the tumor.

Bacci G, Bertoni F, Longhi A, Ferrari S, Forni C, Biagini R, Bacchini P, Donati D, Manfrini M, Bernini G, Lari S.

Department of Musculoskeletal Oncology, Istituto Ortopedico Rizzoli, Bologna,
Italy. gaetano.bacci@ior.it

BACKGROUND: In primary central high-grade osteosarcoma, a number of distinct
subtypes have been identified, but little is known about the response to

METHODS: The authors investigated whether the subtypes correlated with histologic response to chemotherapy in 1058 patients with osteosarcoma of the extremities who were treated with neoadjuvant chemotherapy over the last 20 years. The tumors were classified as osteoblastic (70%), chondroblastic (13%), fibroblastic (9%), and telangiectatic (6%). At diagnosis, 911 patients had localized disease and 147 had resectable lung metastases.

RESULTS: The response to preoperative chemotherapy was good (90% or more tumor necrosis) in 59% of patients and poor (< 90% tumor necrosis) in 41% of patients. The rate of good responses was significantly higher (P = 0.0001) in the fibroblastic (83%) and telangiectatic (80%) tumors and significantly lower in chondroblastic tumors (43%). Prognosis was significantly correlated with the histologic subtypes. The 5-year overall survival rate was significantly higher (P = 0.0001) in fibroblastic (83%) and telangiectatic (75%) tumors than in osteoblastic (62%) and chondroblastic (60%) tumors. In all subtypes, except for the chondroblastic subtype, the 5-year overall survival rate was significantly higher (P = 0.0001) in good responders P = 0.0001 (68%) than in poor responders (52%).

CONCLUSIONS: The authors concluded that the histologic subtype of primary central high-grade osteosarcoma of the extremity was strictly correlated with histologic response to chemotherapy and probably, as a consequence, also with prognosis. Further studies are needed to establish whether these results justify a specific therapeutic approach based on the histologic subtype of the tumor.


Zhonghua Bing Li Xue Za Zhi. 2002 Jun;31(3):213-6.

Telangiectatic osteosarcoma: a clinicopathologic analysis of 14 cases.

Liu H, Huang X.

Department of Pathology, Beijing Jishuitan Hospital, Beijing 100035, China.

OBJECTIVE: To investigate the clinicopathologic characteritics and prognosis of
telangiectatic osteosarcoma.

METHODS: The clinical and pathological data of 14 cases of telangiectatic osteosarcoma were reviewed.

RESULTS: Most of these patients were male (9/14). The mean age was 23 years. Most tumors were located in the lower extremities (10/14). The roentgenograms showed a large purely osteolytic lesion. Both medullar and cortical bone were extensively destroyed. The gross specimen showed cystic cavities separated by septa, similar to an aneurismal bone cyst. Microscopically, the septa contained anaplastic cells. A few fine, lace-like osteoid were scattered among these sarcomatous cells. 12 patients were followed-up from 6 months to 84 months. Of seven patients who had developed pulmonary metastasis, six patients died and one alive with lung metastasis. The remaining five patients survived after operation.

CONCLUSIONS: Difficulties in making an early diagnosis and highly malignant of this disease might be the important factors that affect the prognosis of telangiectatic osteosarcoma.


Mod Pathol. 2001 Dec;14(12):1277-83.

Clinicopathologic analysis of HER-2/neu immunoexpression among various
histologic subtypes and grades of osteosarcoma.

Kilpatrick SE, Geisinger KR, King TS, Sciarrotta J, Ward WG, Gold SH, Bos GD.

Department of Pathology, University of North Carolina, Chapel Hill, North
Carolina 27599-7525, USA. scott.kilpatrick@pathology.unc.edu

Overexpression of the HER-2/neu oncogene appears to have prognostic significance in breast cancer. Recently, some have reported a relationship between increased immunohistochemical expression in osteosarcoma and poor clinical outcome. Despite limited data, a pilot trial of Herceptin, which targets the oncogene product, has been initiated for the therapy of some metastatic osteosarcomas (CCG-P9852). Archival formalin-fixed, paraffin-embedded tissue obtained from 41 patients diagnosed with osteosarcoma was examined immunohistochemically by 2 antibodies against the HER-2/neu oncogene product: CB-11 (monoclonal, 1/100) and Oncor (polyclonal, 1/200). All but one tumor (case of recurrent dedifferentiated parosteal osteosarcoma) represented primary tumor samples; when applicable, only prechemotherapy biopsies were analyzed. The study sample included the full spectrum of histologic subtypes and grades of osteosarcoma (25 conventional high grade; 3 telangiectatic; 1 small cell; 6 parosteal; 1 periosteal; and 5 low-grade intramedullary). A case of metastatic breast cancer with known overexpression of the HER-2/neu oncogene served as the positive control.
Complete membranous positivity, considered prognostically significant in breast
cancer, was not seen in any of our osteosarcoma cases. At least focal
cytoplasmic positivity was documented in 40 (98%) tumors using the CB11 antibody and in 34 (83%) using the Oncor antibody. The intensity of the cytoplasmic staining (0, 1-3+) did not correlate with histologic subtype/grade, response to chemotherapy (<90% versus > or = 90% necrosis), metastasis, or survival.
Immunohistochemical overexpression of the HER-2/neu oncogene, defined as
complete membranous positivity, is not present in our series of osteosarcomas.
Cytoplasmic positivity is observed in most osteosarcomas, irrespective of
histologic subtype/grade, and is not associated with response to preoperative
chemotherapy or disease progression.


Pathology. 1999 Nov;31(4):428-30.

Dedifferentiated chondrosarcoma with features of telangiectatic osteosarcoma.

Radhi JM, Loewy J.

Department of Pathology, College of Medicine, Royal University Hospital,
University of Saskatchewan, Saskatoon, Canada.

We describe a 44-year-old female with a known history of a solitary osteochondroma of the scapula followed on X-ray for five years. She then presented with a rapidly growing lump. Imaging studies confirmed the presence of an aggressive looking lesion. Excision was performed and pathology showed a dedifferentiated chondrosarcoma with features of a telangiectatic osteosarcoma.


Hum Pathol. 1999 Oct;30(10):1254-9.

Large cell, epithelioid, telangiectatic osteoblastoma: a unique
pseudosarcomatous variant of osteoblastoma.

Angervall L, Persson S, Stenman G, Kindblom LG.

Department of Pathology, Sahlgrenska University Hospital, Goteborg, Sweden.

A previously undescribed large-cell, epithelioid, and aneurysmal variant of
osteoblastoma with minimal osteoid-production--simulating telangiectatic
osteosarcoma, epithelioid angiosarcoma, and metastatic carcinoma is reported.
The tumor occurred in the mandible of a 14-year-old girl. The light microscopic,
immunohistochemical, ultrastructural, cell proliferation, and DNA-ploidy
studies, as well as the 7-year disease-free follow-up period all indicate a
benign osteoblastic tumor. Cytogenetically, the tumor had a pseudodiploid
karyotype, distinguished by a complex t(1;5;17;22) and a terminal 1q deletion.
Recognition of this unique, pseudomalignant variant of osteoblastoma is
important to avoid an erroneous diagnosis of malignancy.