Telangiectatic Osteosarcoma Research Articles

Telangiectatic osteosarcoma in an infant

Osteosarcoma is one of the most common types of cancer in school age and adolescence being the most common malignant bone tumor in this age group. Osteosarcoma is frequently found in long bones of the extremities. There are very few cases described in children under five years of age. Moreover, according to our revision none in infants. The telangiectatic variant is uncommon, and there are no reports before preschool age. A 10-month-old female infant that presented a lithic tumor of the ninth right rib, which was classified after resection as a telangiectatic osteosarcoma, is presented. Telangiectatic osteosarcoma in the pediatric age is very uncommon. To date, the patient presented a good response to treatment, although the prognosis and survival of this condition are unknown. El osteosarcoma es uno de los tipos de cáncer más común en la etapa escolar y en la adolescencia, y es el más común de los tumores óseos malignos en este grupo de edad. Frecuentemente, el osteosarcoma es hallado en los huesos largos de las extremidades. Existen muy pocos casos descritos en menores de 5 años. Hasta donde se sabe, no hay ningún caso reportado en lactantes. La variedad telangiectásica es poco común y no existen casos reportados antes de la edad pre-escolar. Se presenta el caso clínico de una paciente lactante de 10 meses de edad que presentó un tumor lítico en la novena costilla derecha, que posterior a la resección fue clasificado como osteosarcoma telangiectásico. El osteosarcoma telangiectásico en la edad pediátrica es poco común. A la fecha, la paciente ha presentado buena respuesta al tratamiento, aunque se desconoce el pronóstico y la supervivencia de este padecimiento.

Radiodiagnostic dilemmas of telangiectatic osteosarcoma: A case report

The telangiectatic osteosarcoma (TGS), an extremely lytic and hemorrhagic variant of the osteosarcoma, presents in the same age group and location as a classical osteosarcoma but has a radiographic appearance almost identical to that of an aggressive aneurismal bone cyst, making diagnosis more complex. Here we are reporting a rare case of biopsy proven telangiectatic osteosarcoma in distal tibia of a 12 years old boy, who was misdiagnosed clinically as a case of aneurismal bone cyst.

Bayesian pretest probability estimation for primary malignant bone tumors based on the Surveillance, Epidemiology and End Results Program (SEER) database

In the diagnostic process of primary bone tumors, patient age, tumor localization and to a lesser extent sex affect the differential diagnosis. We therefore aim to develop a pretest probability calculator for primary malignant bone tumors based on population data taking these variables into account. We access the SEER (Surveillance, Epidemiology and End Results Program of the National Cancer Institute, 2015 release) database and analyze data of all primary malignant bone tumors diagnosed between 1973 and 2012. We record age at diagnosis, tumor localization according to the International Classification of Diseases (ICD-O-3) and sex. We take relative probability of the single tumor entity as a surrogate parameter for unadjusted pretest probability. We build a probabilistic (naïve Bayes) classifier to calculate pretest probabilities adjusted for age, tumor localization and sex. We analyze data from 12,931 patients (647 chondroblastic osteosarcomas, 3659 chondrosarcomas, 1080 chordomas, 185 dedifferentiated chondrosarcomas, 2006 Ewing's sarcomas, 281 fibroblastic osteosarcomas, 129 fibrosarcomas, 291 fibrous malignant histiocytomas, 289 malignant giant cell tumors, 238 myxoid chondrosarcomas, 3730 osteosarcomas, 252 parosteal osteosarcomas, 144 telangiectatic osteosarcomas). We make our probability calculator accessible at http://ebm-radiology.com/bayesbone/index.html . We provide exhaustive tables for age and localization data. Results from tenfold cross-validation show that in 79.8% of cases the pretest probability is correctly raised. Our approach employs population data to calculate relative pretest probabilities for primary malignant bone tumors. The calculator is not diagnostic in nature. However, resulting probabilities might serve as an initial evaluation of probabilities of tumors on the differential diagnosis list.

Use of routine histopathology and factor VIII-related antigen/von Willebrand factor immunohistochemistry to differentiate primary hemangiosarcoma of bone from telangiectatic osteosarcoma in 54 dogs.

Hemangiosarcoma (HSA) of bone and telangiectatic osteosarcoma (tOSA) can appear similar histologically, but differ in histogenesis (malignant endothelial cells versus osteoblasts), and may warrant different treatments. Immunohistochemistry (IHC) for endothelial cell marker factor VIII-related antigen/von Willebrand factor (FVIII-RAg/vWF) is a well-documented ancillary test to confirm HSA diagnoses in soft tissues, but its use in osseous HSA is rarely described. Archived samples of 54 primary appendicular bone tumours previously diagnosed as HSA or tOSA were evaluated using combination routine histopathology (RHP) and IHC. Approximately 20% of tumours were reclassified on the basis of FVIII-RAg/vWF immunoreactivity, typically from an original diagnosis of tOSA to a reclassified diagnosis of HSA. No sample with tumour osteoid clearly identified on RHP was immunopositive for FVIII-RAg/vWF. RHP alone was specific but not sensitive for diagnosis of HSA, compared with combination RHP and IHC. Routine histopathological evaluation in combination with FVIII-RAg/vWF IHC can help differentiate canine primary appendicular HSA from tOSA.

Telangiectatic osteosarcoma: a review of 87 cases.

Telangiectatic osteosarcoma (TOS) is a rare subtype of osteosarcoma. We analyzed (1) oncologic outcome in a large homogeneous series and (2) the role of prognostic factors on prognosis, local recurrence and metastasis. Eighty-seven patients (47 males, 54%) were retrospectively analyzed. All except 4 had extracompartmental disease, and ten patients had lung metastasis at diagnosis. Pathologic fracture was present in 27 cases (31%). Seventy-eight patients were treated with neoadjuvant chemotherapy; nine had surgery as first treatment. Limb-salvage surgery was performed in 71 cases, amputation in 14, and rotationplasty in one. One patient died before surgery. Possible prognostic factors were statistically evaluated. Overall survival was 60.7% at 10years of follow-up. Fifty-one patients were disease-free (58.6%), 2 were alive with disease (2.3%), 31 died with disease (35.6%), and 3 died of other causes (3.4%). Ten local recurrences were observed (11%). Twenty-five patients (29%) developed lung (22) or bone (3) metastases. No statistical difference was found considering age, metastases at diagnosis, gender, pathologic fracture, tumor volume, compartmental status, number of neoadjuvant chemotherapy agents and treatment. Induced necrosis was significant at both univariate and multivariate analysis (p<0.0001). TOS does not have a poor prognosis as previously reported in literature, with a survival of about 60% at 10years. Most of patients can be cured with neoadjuvant chemotherapy plus surgery (limb sparing surgery is possible and safe). Tumor response to chemotherapy as induced necrosis was the only significant prognostic factors on survival, even if small tumor volume at diagnosis correlates with better prognosis at univariate analysis. IV.

Aneurysmal Bone Cyst: An Analysis of 38 Cases and Report of Four Unusual Surface Ones.

Aneurysmal bone cyst (ABC) is a benign expansile bone tumor, most commonly involving the medulla of long bones. ABC rarely arises within the cortex or in the subperiosteal region, radiographically mimicking other conditions, in particular surface osteosarcomathat is low-grade in nature and may go secondary ABC changes, and telangiectatic osteosarcoma. Both of these are sometimes mistaken microscopically for primary ABC. We review the characteristics of ABC cases in our center and report four unusualsurface ABCs arising in the subperiosteal or cortical region of long bones, identified among 38 histologically proven ABCs during a four-year period in our center. The surface ABCs occurred at an older agewith a predilection for diaphysis of femur, tibia, and humerus.

Mutation Analysis of H3F3A and H3F3B as a Diagnostic Tool for Giant Cell Tumor of Bone and Chondroblastoma.

Specific H3F3A driver mutations and IDH2 mutations were recently described in giant cell tumor of bone (GCTB) and H3F3B driver mutations in chondroblastoma; these may be helpful as a diagnostic tool for giant cell-containing tumors of the bone. Using Sanger sequencing, we determined the frequency of H3F3A, H3F3B, IDH1, and IDH2 mutations in GCTBs (n=60), chondroblastomas (n=12), and other giant cell-containing tumors (n=24), including aneurysmal bone cyst, chondromyxoid fibroma, and telangiectatic osteosarcoma. To find an easy applicable marker for H3F3A mutation status, H3K36 trimethylation and ATRX expression were correlated with H3F3A mutations. In total, 69% of all GCTBs harbored an H3F3A (G34W/V) mutation compared with 0% of all other giant cell-containing tumors (P<0.001), whereas 70% of chondroblastomas showed an H3F3B (K36M) mutation compared with 0% of other giant cell-containing tumors (P<0.001). Diffuse H3K36 trimethylation positivity was more often seen in mutated H3F3A GCTBs compared with other giant cell-containing tumors (P=0.005). ATRX protein expression was not correlated with H3F3A mutation status. Hotspot mutations in IDH1 or IDH2 were absent. Our results show that H3F3A and H3F3B mutation analysis appears to be a highly specific, although less sensitive, diagnostic tool for the distinction of GCTB and chondroblastoma from other giant cell-containing tumors. Although H3K36 trimethylation and ATRX immunohistochemistry cannot be used as surrogate markers for H3F3A mutation status, mutations in H3F3A are associated with increased H3K36 trimethylation, suggesting that methylation at this residue may play a role in the etiology of the disease.

Differential diagnostic value of "blue reticulated chondroid-like material" in aneurysmal bone cysts: a classic histopathologic analysis of 215 cases.

Our classic histopathologic study of aneurysmal bone cyst (ABC) revealed that "blue reticulated chondroid-like material" (BRC) is characteristic of ABC. The light microscopic findings were retrospectively analyzed in 215 cases of ABC, including 101 primary and 114 secondary cases. In addition, 22 cases of telangiectatic osteosarcoma (TOS) were drawn from the same source and used as a control. We found the presence of typical BRC in 24 (23.8%) of 101 cases of primary ABC and in six (5.3%) of 114 cases of secondary ABC, with an overall incidence of 30 (14%). None of the cases of TOS showed BRC. BRC was significantly more common in primary ABC than in secondary ABC (P < .05) and in patients 19 years or younger than in those 20 years or older (P < .05). BRC appears to be a unique histopathologic feature of ABC, making it valuable to differentiate benign ABC from TOS. Simple H&E stain can be economically performed anywhere.

Primary telangiectatic osteosarcoma of a non-functioning kidney. A case report

Abstract Pure renal sarcomas are rare; sometimes they are related to the renal capsule or blood vessels and a few cases of osteosarcoma have been reported. We report an unusual case of renal osteosarcoma in an 80-year-old man who underwent nephrectomy for pyelo-ureteral stenosis and hydronephrosis. The tumor was hemorrhagic and attached to the pyelocaliceal surface. Histopathology revealed a pleomorphic neoplasm with features of telangiectatic osteosarcoma. No areas of transitional or renal cell carcinoma or other sarcomatous component were present. Relevant features, such as calcifications and osseous metaplasia, were present at the implantation zone of the tumor. The present case differs from previously reported ones as it was an unexpected finding observed in a non-functioning kidney with good clinical behavior and corresponded to an unusual morphologic variant of osteosarcoma, the telangiectatic type. Finally, the relation with areas of calcification and ossification poses interesting questions as to its histogenenis.

Accuracy of different preoperative biopsy techniques in diagnosis of osteosarcomas and their value in prognostic evaluation

To study the difference in pathologic diagnostic accuracy among different histologic subtypes of osteosarcoma and different methods of preoperative biopsy, and the influence of diagnostic accuracy on prognosis of osteosarcoma. The preoperative biopsies, complete clinical, radiological and pathological data of 347 pathologically confirmed osteosarcomas were evaluated. According to the Pathological Diagnostic and Technical Specifications, the accuracy of preoperative biopsies was divided into 6 grades. 1: definite diagnosis, 2: basically definite diagnosis, 3: significant diagnosis, 4: descriptive diagnosis, 5:inadequate sampling, 6:misdiagnosis. 1 to 3 were defined as successful diagnosis,while 4 to 6 were defined as unsuccessful diagnosis. Of the 347 biopsies, 252 were CT-guided needle biopsies by the radiologists, and 95 were core-needle biopsies by orthopedic surgeons without CT-guidance. The latter showed a higher overall biopsy success rate (97.9%) in all osteosarcomas. Biopsies by surgeons showed a higher biopsy success rate (95.4%) in conventional osteosarcoma, but lower success rate in telangiectatic (55.6%) and low-grade central osteosarcomas (63.7%). The accuracy of pathologic diagnosis of preoperative biopsy was related to patients' age, serum AKP level, imaging diagnosis, method of biopsy and the subtype of osteosarcoma. Comparing the groups with successful and unsuccessful diagnosis, there were significant differences in recurrence rate and mortality after operation (P<0.01). The accuracy of pathologic diagnosis of preoperative biopsy are related to recurrence rate and mortality after operation. Biopsy by orthopedic surgeons without CT-guidance is reliable and safe, followed by primary diagnosis at frozen section and final diagnosis by routine pathologic sections for osteosarcomas located in the long bones of the extremities. Close integration of the preoperative pathologic diagnosis with clinical and radiological data will improve the accuracy of diagnosis.

Prognostic factors and survival rate of osteosarcoma: A single-institution study.

Osteosarcoma is a highly malignant primary bone tumor. The study aim to evaluate the prognostic factors influencing the survival rate in our center. This was a retrospective cohort study of all patients treated between January 2005 and December 2010. We included 163 patients with an age range of 6-59 years (median = 19). The median follow-up was 47 months (range 36-84). The overall survival in patients who completed chemotherapy and surgery (n = 117) was 72% at 2 years and 44% at 5 years. Histologically, 99 (85%) had osteoblastic, 6 (5%) had chondroblastic and 3 (2.5%) had telangiectatic osteosarcoma. Limb salvage surgery was performed in 80 (49%) and 41 (25%) underwent amputation. However, 46 patients (28%) underwent no surgical intervention and incomplete chemotherapy. In total, 38/79 patients had a good chemotherapy response. There was a significantly better survival rate for limb salvage versus amputation. Independent prognostic factors for survival are compliance to treatment and presence of lung metastasis. The overall survival of osteosarcoma patients was influenced by the presence of pulmonary metastases and compliance to treatment. Histological subtype, different chemotherapy regimens and histological necrosis after chemotherapy did not significantly influence survival. The patients who did not complete treatment had significantly poorer survival.

From aneurysmal bone cyst to telangiectatic osteosarcoma with metastasis in inguinal lymph nodes: Case report

Aneurysmal bone cyst is a benign bone lesion composed of blood filled cystic cavities lined by fibrous septa. Its malignant transformation of is a rare event. We report a case of a lesion in the second metatarsal bone in a 29-year-old male, presented as a slight swelling of the right foot. After the curettage had been done, the diagnosis of aneurysmal bone cyst was made but the recurrence occurred 4 years later. The biopsy of the recurrent tumor showed compact neoplastic tissue consistent with diagnosis of giant cell tumor with malignancy. The malignant component was recognized as a high grade sarcoma with osteoid production. A tumor mass with the whole II metatarsal bone was extirpated and a resected part of fibula was transplanted. A year later, another recurrence occurred, an amputation was performed and a teleangiectatic osteosarcoma with ingvinal lymph nodes metastases was diagnosed. No other tumor mass was confirmed, either clinically or by imaging techniques at the time of his third operation. He died 4 months later with multiple pulmonary metastases. We emphasize the importance of team work in order to achieve the accurate diagnosis, highlighting careful radiological examinations, good sampling and awareness of unusual cases in bone tumor pathology.

Lateral leg pain

AP radiograph demonstrates a well-defined, expansile, lytic lesion of the proximal fibula with marginal sclerosis, while MRI demonstrates a solid, enhancing lesion with a single small focus of cystic signal abnormality. Histopathology demonstrates multinucleated giant cells seen in a background of spindle cells. The solid variant of aneurysmal bone cyst (S-ABC) is a rare entity, constituting 5–7.5 % of all ABCs [1, 2]. The term S-ABC was first introduced by Sanerkin et al. in 1983, when the authors described solid lesions with the same histological features seen in the walls of ABCs [3]. LikeABC, S-ABCwas previously considered a non-neoplastic, reactive lesion, but recent studies have shown that pathogenesis may relate to cytogenetic abnormalities, specifically chromosomal translocations involving the USP6 gene [4–6]. The mean age at presentation of S-ABC is typically in the second or third decade, and is slightly more prevalent in females. Pain, swelling, and/or palpable mass are common presenting symptoms. S-ABC of the spine can produce radiculopathy. S-ABC tends to occur in the face and spine, femur and tibia, and short tubular bones of the hands and feet [1, 2, 5, 7]. When occurring in the mandible, maxilla, hands, or feet, S-ABC may be referred to as “giant cell reparative granuloma” [4, 5, 7]. Similar to ABC, S-ABC typically presents on radiographs as a geographic, lucent, expansile lesion with endosteal scalloping or cortical thinning without matrix mineralization. S-ABC demonstrates a narrow zone of transition with marginal sclerosis, which may be complete in more than half of cases [1, 2, 4, 7, 8]. In long bones, S-ABC is often eccentric and most commonly involves the metaphysis. In the spine, SABC typically occurs in the posterior elements. At MRI, S-ABC demonstrates homogenous decreased signal on T1-weighted sequences without internal hemorrhage. On T2-weighted imaging, S-ABC appears mostly solid with moderately increased signal and scattered cystic areas of fluid signal [7–9]. However, in contrast to ABC, these cystic areas are less common and do not demonstrate septations or fluidfluid levels typical of ABC [7, 9]. Following contrast administration, S-ABC demonstrates diffuse uniform enhancement, rather than peripheral/septal enhancement commonly seen with ABC [7–9]. The differential diagnosis for S-ABC may include ABC, giant cell tumor, chondroblastoma, and telangiectatic osteosarcoma [5, 7, 8].While S-ABCmay be difficult to distinguish from ABC clinically or radiographically, there are characteristic differences on MRI discussed above. GCT occurs in slightly older patients, most often involves the epiphysis, and less commonly demonstrates marginal sclerosis. Chondroblastoma demonstrates chondroid mineralization and signal intensity, involves the epiphysis, and usually incites marked inflammation. Telangiectatic osteosarcoma often has a wide zone of transition with cortical disruption, aggressive periosteal reaction, and soft tissue mass. Due to symptoms and potential for growth, S-ABC is often treated with curettage and bone grafting, as in this patient The case presentation can be found at doi: 10.1007/s00256-014-2049-5

Time-trends on incidence and survival in a nationwide and unselected cohort of patients with skeletal osteosarcoma

Background. This study describes time-trends on epidemiology, subtypes and histopathological entities of osteosarcoma (OS) in a nationwide and unselected cohort of OS patients in Norway between 1975 and 2009. Few nationwide studies are published, and we still have particularly limited knowledge regarding patients not included in clinical trials comprising about half of the OS population.Method. Histologically verified skeletal OS for all subgroups were included, resulting in 473 eligible cases from a total of 702 evaluated patients. To ensure completeness, the present cohort was based on all cases reported to the Norwegian Cancer Registry, complemented with data from all Norwegian hospitals involved in sarcoma management. Survival analyses were performed with overall and sarcoma-specific survival as endpoints.Results. Mean annual age-standard incidence amounted to about 3.8 per million in male and 2.8 per million in female with no clear time-trends. The male to female ratio was 1.4. Peak incidence was observed in the second decade for both genders. Conventional OS comprised 71.2% of all cases, while low grade OS represented 10.4% and telangiectatic OS only 1.3%. The most common primary site of OS was femur and tibia, respectively. The axial to appendicular ratio increased with the age. The overall 10-year survival did increase from about 30% during the late 1970s to around 50% 20 years later, with no subsequent improvement during the last two decades. Axial tumours, age above 40 years and overt metastatic disease at time of diagnosis were all negative prognostic factors.Conclusion. No improvement in the overall survival for OS since the 1990s was documented. The survival rates are still poor for elderly people, patients with axial disease and in the primary metastatic setting. The average incidence rate of skeletal OS in Norway was in line with international figures.

41. Case report: telangiectatic osteosarcoma of the left humerus in a 13 year old Girl

Telangiectatic osteosarcoma is a rare variant, representing around 3% of osteosarcomas overall. The main differential radiographi-cally, grossly and on histology is with aneurysmal bone cyst and both these lesions tend to occur in the metaphysis of long bones with a peak incidence in the 2ns decade. We present the case of a 13-year-old girl who attended the Women’s and Children’s Hospital, Adelaide with left upper arm pain for 4 weeks after a fall in 2012. An X-ray showed a lytic destructive lesion of the proximal left humerus while magnetic resonance imaging revealed features highly suggestive of telangiectatic osteosarcoma. The lesion was biopsied which confirmed osteosarcoma, with difficulty subtyping due to the limited material available. After two cycles of chemotherapy the patient underwent a limb salvage operation. The specimen was sent to pathology where histology confirmed the diagnosis of telangiectatic osteosarcoma. We review and discuss the clinical, imaging, and pathological features of this rare variant of osteosarcoma.

Telangiectatic osteosarcoma, a rare complication of Paget's disease of bone

Paget’s disease of bone (PDB) is the second most common metabolic bone disease. This condition, characterised by abnormal bone remodelling, has a prevalence of 5-8% in patients of European ancestry over the age of 55 years. 1-4 The majority of patients are asymptomatic. Diagnosis is based on the distinct radiological picture or on the elevation of serum alkaline phosphatase (ALP). Malignant sarcomatous degeneration is a rare ( 5-8 Osteosarcoma is considered to be a rare and devastating complication of PDB. We report on a confirmed case of very rare telangiectatic osteosarcoma in monostotic PDB.

Neglected telangiectatic osteosarcoma of the femur presenting as surgical emergency

Introduction: telangiectatic osteosarcoma is a rare and aggressive subtype of intramedullary osteosarcoma. the distal femur is the most common site. case report: We present a case of telangiectatic osteosarcoma of the femur in a 15-year-old male. the tumor was neglected for six months. the patient had severe anemia with hemoglobin of 5 g/dL. radiography showed an expansive lytic lesion of the distal end of the femur with cortical destruction, focal periosteal reaction and a pathologic fracture. It showed massive extension to adjacent soft tissue. Given the advanced stage of the disease, an amputation of the limb was performed. Gross examination of the resected distal femur revealed a 22x5 cm intramedullary multicystic hemorrhagic and destructive tumor with cortical destruction and extension into the adjacent soft tissues. Histologically, the tumor showed blood-filled spaces lined by giant cells, separated by septa with malignant tumor cells. An immature bone osteoid kind was observed. Numerous mitotic figures were noted. the resection

Osteogenic tumors of bone

In this paper we provide an overview of benign and malignant osteogenic bone tumors. We describe the diagnostic features, radiographic findings, and pertinent ancillary studies needed to diagnose these bone-forming lesions. We begin with osteoid osteoma and osteoblastoma, which are histologically bland and eminently benign with rare possible exceptions. On the other end of the behavioral spectrum is osteosarcoma, which encompasses many subtypes ranging from high-grade osteogenic osteosarcoma to less overtly osteogenic lesions such as telangiectatic and small cell osteosarcoma. While classic osteogenic osteosarcoma can be easily recognized by its high grade morphology and formation of extracellular lace-like osteoid, its variants may pose diagnostic dilemmas as their differential diagnoses can include benign, fibrous, and vascular lesions, among others. Recognition of these variants is essential to avoid diagnostic pitfalls. In equivocal cases, some forms of osteosarcoma have shown molecular alterations that may prove diagnostically useful.

Giant Cell Tumour of the Anterior rib arc Masquerading as a Primary Breast Lump

Sir, A 28-year-old male was referred to our centre for further evaluation of a lump in the right breast. He was being conservatively managed at an outside centre with a presumed clinical diagnosis of gynecomastia. His past, medical and family histories were unremarkable. Clinical examination revealed a well circumscribed, mildly tender, 5 × 4 cm hard lump in the right breast overlying anterior arc of the right third rib, just lateral to the sternochondral junction. The overlying skin was normal; there was insignificant right axillary adenopathy. All hematological and biochemical investigations were within normal limits. A chest skiagram and a subsequent chest computerized tomography demonstrated a 5 × 4 cm expansile, lytic lesion involving the anterior arc of the right third rib with cortical thinning and disruption and with adjacent soft tissue invasion. (Figure 1a) A bone scan revealed an isolated increased uptake in the right third rib. (Figure 1b) A fine needle aspiration and a subsequent trucut biopsy were suggestive of a Giant cell tumour (GCT). Following diagnosis, an anterior thoracotomy and a wide resection of the third rib lesion was performed; the resultant bony defect was bridged with a prolene mesh. (Figure 2a, b) Macroscopic examination revealed an irregular tumour measuring 5.0 × 3.5 × 2.5 cm showing large chondroblastic areas along with areas of osteoid production. The tumour cells were round, slightly elongated with vesicular to hyperchromatic nuclei and moderate cytoplasm. Many osteoclastic giant cells were also seen, the final impression was that of a giant cell tumour rib with reactive osteiod formation. (Figure 3a, b) The patient remains well without evidence of recurrence one and a half years following surgery. Fig. 1 a CT scan showing a 5 × 4 cm expansile, lytic lesion involving the anterior arc of the right third rib with cortical thinning and disruption and with adjacent soft tissue invasion. b A bone scan showing an isolated increased ... Fig. 2 a, b H&EX40- Showing Giant cell tumour rib with reactive osteiod formation. The tumour cells are round to elongated tumour cells with vesicular to hyperchromatic nuclei and moderate cytoplasm, many osteoclastic giant cells are also seen Fig. 3 a Intra operative clinical photograph following removal of the tumour. b Clinical photograph of the specimen Giant cell tumor of bone is a distinct clinical, radiological and pathologic entity accounting for about 4–5 % of all primary bone tumours. It is a benign but locally aggressive neoplasm, classically seen as a purely lytic lesion of the epiphyseal or metaphyseal-epiphyseal region of long tubular bones extending to the articular surface. Around 60 % of the tumours arise around the knee joint, isolated cases have been reported in the scapula, sternum, patella, vertebra, skull, and talus [1]. A rib is an uncommon site for origin of a GCT with a reported incidence of less than one percent. Even in the cases involving the rib, most were located in the posterior arc [1, 2], anterior arc involvement was noted in our patient. The majority of patients with GCT will present with a lytic geographic lesion that destroys the involved bone [3], approximately 20 % are associated with a soft tissue component. Histologically, GCT shows a diffuse proliferation of multinucleated, osteoclast-like giant cells in a background of oval- to spindle-shaped mononuclear stromal cells [4]; the differential diagnosis includes brown tumours, telangiectatic osteosarcoma, malignant fibrous histiocytoma, chondroblastoma, and aneurysmal bone cysts. GCTs are locally aggressive tumors and hence wide excision is usually recommended in all cases [5]. A majority of the patient typically have a benign course, however, a small subset of them (<5 %) show evidence of metastatic involvement, usually to the lung. In conclusion, GCT arising from the chest wall is rare and difficult to diagnose, especially when the tumour is located in the anterior arc of the ribs; the differential diagnosis easily lends itself to a primary breast lump.

Primary Cutaneous Osteosarcoma of the Skin

Dermal or subcutaneous involvement of extraskeletal osteosarcoma is uncommon, and primary cutaneous osteosarcoma of the skin is even rarer, with only few cases well characterized. The authors present 2 cases of this infrequent skin neoplasm. A 76-year-old woman with a nodule on left malar area and an 82-year-old man with a hard nodule on the right temple. First patient's biopsy findings were a dermal lesion mostly composed of malignant osteoid material, with atypical rhabdoid cells intermingled, which was diagnostic of osteoblastic osteosarcoma. Excision of the lesion of the second patient showed a dermal proliferation of atypical spindle-shaped and pleomorphic cells, scattered multinucleated osteoclasts-like cells, and irregular malignant osteoid material. In some fields, atypical cells showed a pseudovascular pattern. Close to this exophytic lesion, a small nest of basal cell carcinoma was observed. Final diagnosis was collision of osteoblastic and telangiectatic primary osteosarcoma and superficial basal cell carcinoma. Both patients have not presented recurrence or metastatic disease after 12 and 9 months of follow-up, respectively. Clinical and histopathologic characteristics of the primary cutaneous osteosarcoma are summarized, and the differential diagnosis of this entity with other benign and malignant skin neoplasms, which can, eventually, show osteoid material.