Hirotaka Nakano

Intramuscular solitary fibrous tumor : A clinicopathological case study

We present a case of extrapleural solitary fibrous tumor arising within the muscle, an unusual and hitherto-undescribed tumor lesion. A 42-year-old woman presented a painless mass in her left thigh. The lesion was depicted as an intramuscular mass that enhanced on both CT and MRI, showing quite rich tumor vascularity. The histological features of the tumor were spindle cell proliferation with various histological patterns, typical fibrocollagenous background, and positive immunoreactivity for CD-34.

RT-PCR Suggests Human Skeletal Muscle Origin of Alveolar Soft-Part Sarcoma

In 1952, Christopherson et al. proposed that alveolar soft-part sarcoma (ASPS) was a distinct entity with unique clinical and pathological features. Since their report, its histogenesis has not been determined. In order to clarify the histogenesis of ASPS, a study using reverse transcription polymerase chain reaction using cDNAs from MyoD1 and myogenin, and the actin filament from human-skeletal-muscle-related mRNAs has been performed in 5 cases of ASPS. The expression of MyoD1 and myogenin was determined in 5 and 2 cases of the 5 cases, respectively. Moreover, expression of the many mRNAs from the actin filament of skeletal muscle was also found in ASPS. According to these findings, it is now postulated that ASPS is of skeletal muscle origin.

Hyperthermic isolated regional perfusion for the treatment of osteosarcoma in the lower extremity

BACKGROUND In order to reduce the systemic toxity of cisplatin and to increase the effect on the local tumor, facilitating limb-preserving procedures, we have been using hyperthermic isolated regional perfusion (HIRP) for the treatment of osteosarcoma in addition to preoperative chemotherapy. MATERIALS AND METHODS Twenty patients with an osteosarcoma in a lower extremity were treated with both preoperative chemotherapy and HIRP. RESULTS The chemotherapeutic effects of preoperative chemotherapy with HIRP was grade III in 6, and grade IV (no viable cell areas observed) in 7. The surgical margins could be reduced in these 13 cases of good responders showing over 90% necrosis (grade III or grade IV), which mainly involved postnecrotic fibrosis and osteosclerosis. CONCLUSION HIRP can help to control the tumor locally. A more conservative operation was then possible in cases of good responders to preoperative chemotherapy with HIRP.

Mechanical failure of unsupported Huckstep intramedullary nail in malignant bone tumor reconstruction.

Seventeen segmental resections of diaphyseal tumors and five knee resection arthrodeses were reconstructed using the Huckstep nail with intercalary bone grafts (fibula), cementation, and ceramic and titanium spacers. Although the bone defects were 0 to 25.5 cm in length (mean, 13.1 cm), all patients had relief of pain and were able to move alone with a wheelchair or a cane. Nail breakage occurred in four patients who had reconstruction surgery using a ceramic spacer (four patients without intercalary fibula graft and one patient with intercalary fibula graft). The nail survival rate was significantly better in the patients with reinforcement by vascularized fibular graft (100% at 5 years and 75% at 10 years; n = 8) than in the patients without reinforcement by vascularized fibular graft (87.5% at 3 years and 0% at 5 years; n = 14). Huckstep nailing is a useful option for reconstruction of large bone defects in diaphyseal tumors and knee resection arthrodesis. It should be used in combination with a vascularized fibula graft to prevent mechanical failure and to achieve durability of limbs with defects from primary bone tumors. Huckstep nailing with nonbiologic augmentation is good for palliative surgery for bone metastases in patients with a shorter expected survival rate.

Long-term local intensive preoperative chemotherapy and joint-preserving conservative surgery for osteosarcoma around the knee.

This study evaluated conservative joint-sparing surgery for patients with osteosarcoma around the knee. Of 23 patients with stage IIB osteosarcoma around the knee, 5 were treated with long-term (30-56 weeks) local intensive preoperative chemotherapy consisting of high-dose methotrexate, intra-arterial and intravenous cisplatinum, doxorubicin, and hyperthermic isolated regional perfusion. More conservative resection, sparing the knee joint, was performed with smaller sufficient surgical margin in these 5 patients, preserving good limb function. Excellent local effects were achieved in the resected specimens. These results suggest long-term local intensive preoperative chemotherapy, including intra-arterial cisplatin and hyperthermic isolated regional perfusion, help control local tumor and allow for more conservative surgery.