A unique case of adamantinoma-like Ewing sarcoma in the calcaneus, exhibiting prominent squamous differentiation and displaying EWSR1 gene rearrangement.

Adamantinoma-like Ewing sarcoma is uncommonly reported in the skeletal sites, including small bones of the feet.A 15-year-old girl presented with pain and swelling in her left foot, leading to difficulty in walking for 8 months. Plain radiograph revealed an ill-defined, lytic-sclerotic lesion without significant periosteal reaction in her left calcaneus. Magnetic resonance imaging (MRI) revealed an expansile lesion involving the anterior calcaneus, which was hypointense on T1 and heterogeneously hyperintense on T2-weighted sequences, infiltrating the adjacent bones and soft tissues. On imaging, the differential diagnoses considered were a giant cell tumor and other primary bone tumors.Histopathological examination revealed a tumor composed of small round cells, with interspersed keratin pearls. Immunohistochemically, the tumor cells were positive for CD99/MIC2, pan-cytokeratin (AE1/AE3), p40, p63, NKX2.2, and synaptophysin. Diagnosis of adamantinoma-like Ewing sarcoma was offered on the initial biopsy. Furthermore, the tumor cells revealed EWSR1 gene rearrangement by fluorescence in situ hybridization, confirming this diagnosis. The patient underwent neoadjuvant chemotherapy, had a poor response, and finally underwent below-knee amputation.This constitutes a rare case of adamantinoma-like Ewing sarcoma in the calcaneus. Ewing sarcoma may be considered as a differential diagnosis for intraosseous lytic-sclerotic lesions, even without significant periosteal reaction, at unusual sites, such as the bones of the foot. Awareness of this entity and application of ancillary techniques is recommended for its exact diagnosis and in differentiating this rare variant from its diagnostic mimics. This case also indicates a poor chemotherapy response in this unusual variant of Ewing sarcoma, occurring in the calcaneus.

Chondrosarcoma of bone: does the size of the tumor, the presence of a pathologic fracture, or prior intervention have an impact on local control and survival?

AIMS AND OBJECTIVES: We studied 45 patients with chondrosarcoma, without metastasis at diagnosis, who were surgically treated between January 2000 and December 2004 to evaluate the risk factors associated with local recurrence and metastasis. MATERIALS AND METHODS: Fourteen (31%) patients had had some major prior intervention, either in the form of an open biopsy or a curettage / unplanned excision, before presenting to us. Eight patients had pathologic fractures at presentation. None of the patients received adjuvant chemotherapy or radiotherapy. The follow-up duration ranged from 8-75 months. All survivors had a minimum follow-up of 36 months (range 36-75 months). RESULTS: There were 11 grade 1 (24.5%), 23 grade 2 (51%), and 11 grade 3 (24.5%) chondrosarcomas. Thirty-two (71%) patients had tumors that were larger than 8 cm in the greatest dimension. Margins were adequate in 31 patients. Twenty-five patients had disease relapse; there were four local failures, nine distant failures, and 12 combined failures. At the time of the last review, 12 patients had died, 11 were alive with disease, and 22 were free of disease. The cumulative event-free survival was 44% and the overall survival was 73%. CONCLUSION: Grade of tumor, size of tumor, and adequacy of resection might be important predictors of outcome. Local recurrence is a prelude to distant metastasis and portends poor ultimate survival. The presence of a pathological fracture could indicate biologically aggressive disease, and limb salvage in these cases should be advised with caution. Even in cases where there has been a prior unplanned intervention, local control can be achieved by subsequent adequate resection.

Decision making in primary sacral tumors.

BACKGROUND CONTEXT: Primary tumors of the sacrum are extremely rare lesions. Their management is governed by an interplay of complex factors. Appropriate decision making is crucial to obtain the best possible outcome in terms of maximizing disease control while attempting to minimize neurological dysfunction. PURPOSE: Our study presents the results of a group of patients with primary tumors of the sacrum who were surgically treated by the same multidisciplinary team at a specialist oncology center over a relatively short period of time (5 years). STUDY DESIGN/SETTING: Patients were identified by a retrospective review from a prospectively maintained database. PATIENT SAMPLE: Between January 2000 and December 2005, 17 primary sacral tumors were surgically treated at our institution, a referral center for oncology. OUTCOME MEASURES: We evaluated the outcome in terms of local disease control, residual neurological dysfunction, and complications as a result of surgical intervention. METHODS: There were 12 males and 5 females. The diagnosis included chordoma in six patients, giant cell tumor in seven patients, aneurysmal bone cyst in two patients, and a chondrosarcoma and an osteoblastoma in one patient each. Sixteen of these patients were analyzed. Four lesions had their upper extent at S1, six lesions had their upper extent at S2, four lesions had their upper extent at S3, and two lesions were below S3. Ten cases were treated with wide excision and underwent partial sacral amputations. Five cases had a midline sacral amputation through S1, three through S2, and two through S3. Six benign lesions were treated with curettage. None of the patients received chemotherapy. Four cases received postoperative radiation. The follow-up duration ranged from 18 to 44 months with a mean of 31 months. RESULTS: None of the six patients who presented with loss of bladder and bowel control regained it after surgery. Of the 10 patients who had intact bladder and bowel control preoperatively only 4 retained bladder and bowel control postoperatively. Of the six patients who lost bladder and bowel control postoperatively, four patients had a wide excision where bilateral S2 roots were sacrificed. The other two cases in whom the disease extended up to S1 had curettage. Local recurrence occurred in 4 of the 10 lesions treated with wide excision. All the patients who had inadequate margins recurred. Local recurrence occurred in two of the six lesions treated with curettage. Three of the four cases who received postoperative irradiation developed recurrence. Our wound complication rate was 13%. CONCLUSION: Wide resection with adequate margins gives the best chance of local control and should be the surgery of choice for all malignant primary sacral tumors and in benign lesions involving lower segments when preservation of both S3 roots is possible. Intralesional curettage has a higher risk of local recurrence without providing the certainty of retaining neurological function. To retain bladder and bowel control and minimize neurological dysfunction, it may be worthwhile managing benign sacral tumors that extend above S3 with serial embolization. The administration of parenteral bisphosphonates may prove beneficial in cases of giant cell tumor managed with serial embolization.

Giant cell tumor of bone in children and adolescents.

BACKGROUND: There are very few series that document giant cell tumor of bone (GCT) in the immature skeleton, and the reported incidence in literature varies from 1.8% to 10.6%. The purpose of this study was to document the incidence of GCT in patients with open physis in the Indian population and study the course of the disease with respect to its adult counterpart to see if it behaved any differently. METHODS: Between January 2000 and December 2005, 17 (6%) of 285 surgically treated patients with histologically proven GCT had open physis on imaging. Treatment was directed toward local control without sacrificing joint function, with most lesions treated with intralesional curettage. RESULTS: Fourteen (82%) patients were girls. The most common site was around the knee (53%). Of 15 lesions in tubular bones, 13 were epiphysiometaphyseal in location. An open physis did not prevent GCT from penetrating the epiphyseal cartilage. Histologically, the tumors were typical of GCT. Of 15 patients available for follow-up, 3 (20%) developed local recurrence. CONCLUSIONS: Although the overall incidence of GCT may be higher in the Asian population, the percentage of skeletally immature patients or those nearing skeletal maturity is similar to that described in literature. The biological behavior of the disease is similar to that seen in adults, except a marked female preponderance, principles of treatment, recurrence patterns, and course of the disease mirror the behavior of its adult counterpart.

Limb salvage surgery for osteosarcoma: effective low-cost treatment.

Successful management of osteosarcoma with limb salvage surgery is a challenging problem in the developing world. We report our early results with low-cost chemotherapy (without methotrexate) and low-cost limb salvage surgery. We prospectively collected data for 135 patients with histologically proven high-grade osteosarcoma of the extremities given neoadjuvant chemotherapy and treated with limb salvage surgery between January 2000 and February 2004. A locally designed and fabricated stainless steel customized megaprosthesis was used in 78 patients. Disease status and function was evaluated at followup ranging from 24 to 72 months. Followup data were available for 120 of the 135 patients. There were eight infections, four prosthesis breakages and three loosenings. Eighteen patients had local recurrence; 17 of these patients also developed lung metastases. Seventy-three patients (61%) were disease-free at followup. The group of 34 patients with 100% necrosis had better disease-free survival (79%). According to a modified Enneking system, the average functional score was 25.5 of 30 (85%) for the lower extremity and 20 of 30 (66%) for the shoulder. Our preliminary results suggest osteosarcoma can be managed well in a developing country in a cost-effective way. Limb salvage surgery has now become the standard of care.

Rotationplasty for bone tumors: is there still a role?

We evaluated the disease status and functional results in 30 patients (range, 6-25 years) who underwent rotationplasty for bone sarcomas from January 2000 to February 2004. Plating was used for fixation in all 27 distal femur resections. In the proximal femur tumor, the distal femur was contoured and fixed to the ilium with cancellous screws. In the two cases involving the entire femur, the upper end of the tibia was articulated with the acetabulum in one case and an Austin Moore prosthesis was inserted in the upper end of the tibia in the other. Two patients underwent an amputation after postoperative vascular compromise. Other complications included venous congestion in two patients, who recovered after exploration, partially recovered nerve palsy in one, wound infection in two, local recurrence in one, and nonunion with subsequent bone grafting in one. Functional evaluation was documented in 26 patients with a followup ranging from 24 to 60 months. Using the Musculoskeletal Tumor Society scoring system, the score was 25 or greater in 20 of 26 patients. In appropriately indicated cases, rotationplasty provides good local disease control and good function.

Hemicortical excision for low-grade selected surface sarcomas of bone.

In malignant surface tumors, hemicortical excision in select cases may allow adequate margins with better function. We treated 10 of 22 malignant surface tumors with hemicortical excision and reconstruction from January 2000 to June 2003. There were eight conventional parosteal osteosarcomas, one high-grade surface osteosarcoma, and one surface chondrosarcoma. Six tumors occurred in the femur, two in the tibia and one each in the humerus and radius. Defects were reconstructed with allograft (five), fibula autograft (three), or autogenous iliac crest (two). Internal fixation as suitable was used. Margins were reported uninvolved in all cases. At followup ranging from 40 months to 61 months we observed no local recurrence. Using the MSTS scoring system, six patients had a maximum possible score of 30; the other four had a score of 29. None developed distant metastasis. Though a longer followup is ideal, in selected cases hemicortical excision appears a reasonable procedure that obviates joint replacement. Biological reconstruction with bone could help reduce the incidence of subsequent revision surgery that would likely occur in cases treated initially with conventional excision and replacement with megaprostheses or circumferential intercalary allografts.

Giant cell tumor - distal end radius: Do we know the answer?

BACKGROUND: The distal end of the radius is one of the common sites of involvement in giant cell tumors (GCTs) with reportedly increased propensity of recurrence. The objective of the present analysis was to study the modalities of management of the different types of distal end radius GCTs so as to minimize the recurrence rates and retain adequate function. MATERIALS AND METHODS: Twenty-four patients of distal end radius GCTs treated between January 2000 and December 2004 were retrospectively reviewed. Nineteen cases were available for follow-up with an average follow-up of 37.5 months. There was one Campanacci Grade 1 lesion, nine Grade 2 and 14 Grade 3 lesions. Thirteen (54%) of these patients were treated elsewhere earlier and presented with recurrence. The operative procedures that were performed were: curettage and cementing (five), curettage and bone grafting (seven), excision and proximal fibular arthroplasty (two), excision and wrist arthrodesis (nine) and excision of soft tissue recurrence (one). RESULTS: Functional status was evaluated using Musculo Skeletal Tumor Society scoring system which averaged 78%. The recurrence rate was 32%. Complications included local recurrence (six), nonunion at the graft bone junction (one), infection (one), deformity (two), stiffness (two), subluxation (two) and bony metastasis (one). CONCLUSIONS: The majority of patients undergoing curettage were either Campanacci Grade 1 or 2. Patients undergoing curettage and reconstruction had a better functional result (82%) as compared to arthrodesis or fibular arthroplasty (69%). Previous intervention did not appear to increase the recurrence rates. Even though complications occur, judicious decision-making and an appropriate treatment plan can ensure a satisfactory outcome in the majority of cases.