Parosteal osteosarcoma with low grade chondrosarcoma and liposarcoma components. A rare histologic variant. Case report and literature review.

INTRODUCTION: conventional parosteal osteosarcoma is an uncommon malignant bone tumor, comprising 4% of all osteosarcomas. Although rare, parosteal osteosarcoma is the most common type of osteosarcoma of the bone surface. We present the clinical, histological and imaging characteristics of a rare histologic variant of a parosteal osteosarcoma, review the literature and emphasize the importance of radio-pathological correlation as well as the interpretation of a representative biopsy in order to obtain the correct diagnosis. CASE REPORT: a 36-year old woman began her condition one year prior to admission to the hospital with increased volume in the left knee and pain. Image studies showed a juxtacortical heterogeneous tumor localized on the posterior surface of the distal femoral metaphysis. An incisional biopsy was performed, with the diagnosis of a Parosteal Osteosarcoma and a wide surgical resection was undertaken. According to the findings of the surgical specimen, the diagnosis of a Parosteal Osteosarcoma with low grade chondrosarcoma and liposarcoma components was made. The knowledge of this rare parosteal osteosarcoma variant can lead the orthopedic oncologists to avoid overlooking the adipose component and provide adequate surgical margins. CONCLUSION: we present the clinical, histological and imaging characteristics of a Parosteal Osteosarcoma with low grade liposarcoma and chondrosarcoma components.

INTRODUCCIÓN: el osteosarcoma parosteal convencional es un tumor óseo maligno poco común, que comprende el 4% de todos los osteosarcomas. Aunque es poco común, el osteosarcoma parosteal es el tipo más común de osteosarcoma de la superficie ósea. Presentamos las características clínicas, histológicas y de imagen de una variante histológica rara de un osteosarcoma parosteal, revisamos la literatura y enfatizamos la importancia de la correlación radio-patológica, así como la interpretación de una biopsia representativa para obtener el diagnóstico correcto. REPORTE DE CASO: mujer de 36 años inició su cuadro un año antes de su ingreso al hospital con aumento de volumen en rodilla izquierda y dolor. Los estudios de imagen mostraron una tumoración heterogénea yuxtacortical localizada en la superficie posterior de la metáfisis femoral distal. Se realizó biopsia incisional, con diagnóstico de osteosarcoma parosteal y se realizó resección quirúrgica amplia. De acuerdo con los hallazgos de la pieza quirúrgica se realizó el diagnóstico de osteosarcoma parosteal con componentes de condrosarcoma y liposarcoma de bajo grado. El conocimiento de esta rara variante de osteosarcoma parosteal puede llevar a los ortopedistas oncólogos a considerar otros componentes y proporcionar márgenes quirúrgicos adecuados. CONCLUSIÓN: presentamos las características clínicas, histológicas y de imagen de un osteosarcoma parosteal con componentes de liposarcoma y condrosarcoma de bajo grado.

Tratamiento multidisciplinario de condrosarcoma gigante de fémur proximal mediante hemipelvectomía externa y reconstrucción con colgajo pediculado tipo fillet flap: presentación de un caso clínico / Multidisciplinary treatment of giant chondrosarcoma of the proximal femur by external hemipelvectomy and reconstruction with a pedunculated fillet flap: presentation of a clinical case / Tratamento multidisciplinar do condrossarcoma gigante do fêmur proximal por hemipelvectomia externa e reconstrução com retalho fillet flap: apresentação de um caso clínico

El condrosarcoma forma parte de los tumores primarios malignos más frecuentes. Las localizaciones pélvicas y de raíz de muslo requerirán abordajes amplios con la consecuente dificultad de cobertura de partes blandas. La hemipelvectomía externa es habitualmente el procedimiento de elección para estas localizaciones. Implica la resección de la extremidad inferior en bloque asociada a la hemipelvis ipsilateral, dando como resultado un gran defecto de cobertura. En algunas circunstancias, la extensa resección de partes blandas hace imposible la utilización de colgajos rotacionales locales. La reconstrucción con colgajo tipo "Fillet flaps" ofrece a estos defectos de partes blandas la opción de lograr una adecuada cobertura. El objetivo del trabajo es mostrar la resolución de un caso poco convencional de condrosarcoma de fémur proximal y su reconstrucción de partes blandas con un método nunca antes utilizado en nuestro medio.

Chondrosarcoma is one of the most frequent malignant primary tumors. Pelvic and proximal femur locations require extensive approaches with the consequent difficulty of soft tissue reconstruction. External hemipelvectomy is usually the procedure for these locations. It involves total en bloc resection of the lower extremity associated with ipsilateral hemipelvis, resulting in a large coverage defect. In some cases, local rotational flaps are impossible. Reconstruction with fillet flaps offers an adequate coverage for soft tissue defects. The objective of this study is to show the resolution of an unconventional case of chondrosarcoma of the proximal femur and its soft tissue reconstruction with a method never before used in our country.

O condrossarcoma é um dos tumores primários malignos mais frequentes. As localizações das raízes pélvicas e da coxa exigirão amplas abordagens com a conseqüente dificuldade em cobrir os tecidos moles. A hemipelvectomia externa costuma ser o procedimento de escolha para esses locais. Envolve a ressecção do membro inferior em bloco associado à hemipelve ipsilateral, resultando em um grande defeito de cobertura. Em algumas circunstâncias, a ressecção extensa de partes moles impossibilita o uso de retalhos rotacionais locais. A reconstrução com retalhos de filé oferece a esses defeitos de tecidos moles a opção de obter uma cobertura adequada. O objetivo deste trabalho é mostrar a resolução de um caso não convencional de condrossarcoma do fêmur proximal e sua reconstrução de partes moles com método nunca antes utilizado em nosso meio.

What Happens to the Articular Surface After Curettage for Epiphyseal Chondroblastoma? A Report on Functional Results, Arthritis, and Arthroplasty.

BACKGROUND: Chondroblastoma is an uncommon, benign, but locally aggressive bone tumor that occurs in the apophyses or epiphyses of long bones, primarily in young patients. Although some are treated with large resections, aggressive curettage and bone grafting are more commonly performed to preserve the involved joint. Such intralesional resection may result in damage to the growth plate and articular cartilage, which can result in painful arthritis. Prior studies have focused primarily on oncologic outcomes rather than long-term joint status and functional outcomes. QUESTIONS/PURPOSES: (1) What local complications can be expected after aggressive intralesional curettage of epiphyseal chondroblastoma? (2) What is the joint survival of a joint treated in this way for chondroblastoma? (3) What additional procedures are used in treating symptomatic joint osteoarthritis after treatment of the chondroblastoma? (4) What are the functional outcomes in this group of patients? METHODS: A retrospective study of our prospectively collected database between 1975 and 2013 was done. We found 64 patients with a diagnosis of chondroblastoma of bone. After applying our selection criteria, 53 patients were involved in this study. We excluded seven patients with tumors initially treated with en bloc resection (five located in the extremities and two in the axial skeleton) and two patients with apophyseal tumors. One patient who underwent nonsurgical treatment and one patient lost to followup were also excluded. The mean age was 18 years (range, 11-39 years); the minimum followup was 2 years with a mean followup 77 months (range, 24-213 months). We analyzed all patients with a diagnosis of epiphyseal chondroblastoma of the limb treated with aggressive curettage and joint preservation surgery. During the period in question, our general indications for curettage were patients with active, painful tumors and those with more aggressive ones that remained intracompartmental, whereas initial wide en bloc resection was indicated in patients who had tumors with an extracompartmental extension breaching the adjacent joint cartilage and massive articular destruction. The tumor location was the distal femur in 14 patients, proximal tibia in 11, proximal humerus in 10, proximal femur in eight, the talus in seven, and elsewhere in the lower extremity in three. Local complications including joint degeneration and tumor recurrence were evaluated. Based on radiographic analysis, secondary osteoarthritis was classified by using the Kellgren-Lawrence grading system from Grade 0 to Grade IV. Patients who underwent joint replacement resulting from advanced symptomatic osteoarthritis were considered to have had joint failure for purposes of survivorship analysis, which was estimated using the Kaplan-Meier method. Functional results were evaluated with the Musculoskeletal Tumor Society functional score by the treating surgeon, who transcribed the results on the digital records every 6 months of followup. RESULTS: Twenty-two patients (42%) developed 26 local complications. The most common local complication was osteoarthritis in 20 patients (77% [20 of 26 complications]); tumor recurrence was observed in four patients; an intraarticular fracture and superficial infection treated with surgical débridement and antibiotics developed in one patient each. Joint survival was 90% at 5 years (95% confidence interval [CI], 76%-100%) and 74% at 10 years (95% CI, 48%-100%). Proximal femoral tumor location was associated with lower survivorship of the joint than other locations showing a 5-year survival rate of 44% (95% CI, 0%-88%; p = 0.000). Of the 20 patients with osteoarthritis, four were symptomatic enough to undergo joint replacement, all of which were for tumors in the proximal femur. The mean Musculoskeletal Tumor Society functional score was 28 of 30 points (93%). CONCLUSIONS: Osteoarthritis was a frequent complication of aggressive curettage of epiphyseal chondroblastoma, and tumors located in the proximal femur appeared to be at particular risk of secondary osteoarthritis and prosthetic replacement. Because chondroblastoma is a tumor that disproportionately affects younger patients, the patient and surgeon should be aware that arthroplasty at a young age is a potential outcome for treatment of proximal femoral chondroblastomas. LEVEL OF EVIDENCE: Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

[Conservative surgery as an alternative treatment of a knee osteosarcoma in the presence of a pathological fracture]. / Cirugía de salvamento como alternativa en el tratamiento de osteosarcoma de rodilla ante la presencia de fractura en terreno patológico.

INTRODUCTION: classical osteosarcoma is defined as a very malignant spindle cell sarcoma, characterized by the production of osteoid matrix, it is the most common primary malignant bone tumor. It is most common among males in their twenties. Factors involved include those related with the skeletal growth and development, pathological fractures, and very young patients who are still growing. Conservative surgery is inappropriate; however, preoperative chemotherapy and a good choice of conservative treatment are an alternative. MATERIAL AND METHODS: a 15-year-old male patient presented at the orthopedics service with a diagnosis of a pathological fracture in the distal third of the right femur and a tumor in the lateral aspect of the knee, with pain and limitation of gait. Based on X-rays, a bone scan and a biopsy, the diagnosis of a fibroblastic osteosarcoma, an Enneking IIB lesion, was made. Treatment consisted of conservative surgery with broad tumor resection involving 18 cm of the femur, resection of the vastus medialis and vastus lateralis, release of the femoral bundle, the popliteal and sciatic nerves, as well as placement of a modular stryker tumor prosthesis, with knee replacement. RESULTS: the clinical and radiological course was appropriate. After a 3-week rehabilitation period the patient was able to walk and the lower limb was salvaged. At 5 months there is no evidence of tumor relapse, the patient can walk properly and has recovered the strength. DISCUSSION: this is a case salvage surgery to treat a pathological fracture resulting from a malignant bone tumor. We think that staging is essential to select the treatment. In the case presented herein a comprehensive management is fundamental to the success of conservative treatment.

Hyperplastic callus formation in osteogenesis imperfecta type V mimicking osteosarcoma: 4-year follow-up with resolution.

We report a case of hyperplastic callus formation that occurred in both femurs in a patient with type V osteogenesis imperfecta (OI), with 4-year follow-up and resolution. The clinical, histological and imaging aspects of this condition are discussed. Recognition of the hyperplastic callus formation in this particular type of OI is important in order to avoid misdiagnosis.

Familial occurrence of osteoid osteoma.

Familial occurrence of osteoid osteoma is an exceedingly rare event. This paper describes the second report of this event, where two siblings presented with this lesion in the same location, the proximal left femur. They both presented at 6 years of age, but 3 years apart.

Osteoid osteoma of the hip. Percutaneous resection guided by computed tomography.

Seven patients with a presumptive diagnosis of osteoid osteoma located at the hip were treated with percutaneous resection of the nidus through computed tomography guidance. Histologic confirmation was obtained in 5 of the 7 patients. The average hospital stay was 27 hours. At followup, from 12 to 40 months, all patients remain asymptomatic. This procedure presents potential advantages that traditional open surgery techniques do not have.