Special AT-rich sequence-binding protein 2 (SATB2) in the differential diagnosis of osteogenic and non-osteogenic bone and soft tissue tumors.

BACKGROUND: The diagnosis of osteosarcoma (OSA) depends on clinicopathological and radiological correlation. A biopsy is considered the gold standard for OSA diagnosis. However, since OSA is a great histological mimicker, diagnostic challenges exist. Immunohistochemistry (IHC) can serve as an adjunct for the histological diagnosis of OSA. Special AT-rich sequence-binding protein 2 (SATB2) was recently described as a reliable adjunct immunohistochemical marker for the diagnosis of OSA. METHODS: We investigated the IHC expression of SATB2 in 95 OSA and 100 non-osteogenic bone and soft tissue tumors using a monoclonal antibody (clone EPNCIR30A). The diagnostic utility of SATB2 and correlation with clinicopathological parameters were analyzed. RESULTS: SATB2 IHC was positive in 88 out of 95 cases (92.6%) of OSA and 50 out of 100 cases (50.0%) of primary non-osteogenic bone and soft tissue tumors. Of the 59 bone tumors, 37 cases (62.7%) were positive for SATB2, and of the 41 soft tissue tumors, 13 cases (31.7%) were positive for SATB2. The sensitivity of SATB2 as a diagnostic test was 92.6%, specificity 50%, positive predictive value 63.8%, and negative predictive value 87.7%. CONCLUSIONS: Although SATB2 is a useful diagnostic marker for OSA, other clinical, histological and immunohistochemical features should be considered for the interpretation of SATB2.

Reconstruction of complete knee extensor mechanism loss with gastrocnemius flaps.

UNLABELLED: We assessed the outcome after reconstruction of traumatic, complete, infected, extensor mechanism loss attributable to high-velocity open knee injuries in eight consecutive patients (all males) who presented to us between February 2005 and September 2007 at an average followup of 24 months. All were treated with gastrocnemius flaps. The loss in extensor mechanism was the patellar tendon in five patients, patella and patellar tendon in two patients, and combined patella, quadriceps, and patellar tendon in one patient. The size of the defect ranged from 8 x 5 cm to 15 x 15 cm. The patients were evaluated for functional outcome of the knee, resolution of infection, range of flexion of the knee, and return to work. Four patients had an excellent outcome whereas the others had a good outcome using the Hospital for Special Surgery knee rating scale. All flaps healed primarily with resolution of infection. The average knee flexion was 110 degrees. All patients except two returned to their original occupation. Three patients had an extensor lag of 5 degrees. The gastrocnemius flap is a good option for open knee injuries with extensor mechanism loss, giving consistent results across a wide spectrum of presentation. LEVEL OF EVIDENCE: Level IV, case series. See the Guidelines for Authors for a complete description of levels of evidence.

Open infected Achilles tendon injury--reconstruction of tendon with fascia lata graft and soft tissue cover with a reverse flow sural flap.

We present a patient with an open, infected Achilles tendon injury with a soft tissue defect of 12 cm x 5 cm and a tendon defect of 10 cm. He underwent a two-stage procedure. A first stage debridement of tendon and soft tissue was followed by a second stage tendo Achilles reconstruction using fascia lata graft and soft tissue cover with a reverse flow sural flap. He had a good functional outcome with minimal donor site morbidity.

Time required for effective action of phenol against giant cell tumour cells.

PURPOSE: To evaluate the time required for effective action of phenol against the giant cell tumour (GCT) cells. METHODS: Fresh GCT cells were harvested from 9 patients with primary GCT of the distal femur (n=4), proximal tibia (n=4), and proximal humerus (n=1), with the Campanacci tumour grades 3 (n=6), 2 (n=2), and 1 (n=1). Specimens were immersed in 80 % phenol for one, 3, 6, and 10 minutes, and were assessed by a single pathologist for irreversible cell death and the depth of phenol penetration. RESULTS: Phenol caused consistent GCT cell death in 6 of the 9 specimens after 3 minutes and in all 9 specimens after 6 minutes, compared to none in controls (p<0.0001). The mean depths of phenol penetration were 15 (range, 11-20) and 19 (range, 15-25) cell thickness after 6 and 10 minutes, respectively (p<0.0001). CONCLUSION: GCT cells immersed in 80% phenol for 6 minutes resulted in consistent cell death.