Akira Kawai

Prosthetic Knee Replacement after Resection of a Malignant Tumor of the Distal Part of the Femur. Medium to Long-Term Results*

We evaluated the medium to long-term results of treatment with a custom prosthetic knee replacement after wide resection of a primary malignant tumor of the distal part of the femur in forty consecutive patients. The duration of follow-up ranged from five to seventeen years (median, eight years). At the time of the latest follow-up, thirty-five (88 per cent) of the forty patients were free of disease and five (13 per cent) were alive with metastatic disease. No local recurrence was observed. Twenty early complications occurred in eighteen patients (45 per cent). Aseptic loosening of the femoral component, which necessitated a revision in eleven patients at an average of fifty-one months, was the most frequent mode of failure. The rate of prosthetic survival, as estimated with use of the Kaplan-Meier method, was 85, 67, and 48 per cent at three, five, and ten years. Univariate analysis demonstrated that the rate of prosthetic survival was significantly worse for male patients, for those in whom at least 40 per cent of the femur had been resected, for those who had had total resection of the quadriceps muscles or subtotal resection (preservation of only the rectus femoris muscle), and for those in whom a straight femoral stem had been used (p < 0.05 for all comparisons). Multivariate analysis showed that the independent adverse prognostic factors for prosthetic survival were male gender, resection of at least 40 per cent of the femur, and fixation of the femoral stem with cement. The rate of limb salvage was calculated, with use of the Kaplan-Meier method, to be 93 per cent at three years and 90 per cent at five and ten years. At the latest follow-up examination, the functional scores according to the classification system of the Musculoskeletal Tumor Society ranged from 14 to 29 points; the mean was 24 points, which represents function that is 80 per cent that of normal. The mean scores in the categories of walking supports and gait were better for the patients in whom the quadriceps muscles had been preserved than for those who had had total or subtotal resection of those muscles. Although advances in imaging and local therapy narrow the indications for an extra-articular resection of a tumor, the implant that was used in the present study continues to be used in approximately 15 per cent of patients who have a fracture or an intra-articular extension of the tumor that necessitates extensive extra-articular resection.

A rotating-hinge knee replacement for malignant tumors of the femur and tibia

We evaluated the 2- to 7-year results of a rotating-hinge knee replacement after excision of malignant tumors of the knee joint. There were 25 distal femoral and 7 proximal tibial replacements. The 5-year prosthetic survival for distal femoral replacements was 88%, compared with 58% for proximal tibial replacements. Seven patients underwent prosthetic exchange: 1 for aseptic loosening, 2 for wound slough and perioperative infection, and 4 for articulating component failure. One patient underwent above-knee amputation owing to skin necrosis. The median functional scores at the latest follow-up were 27 by the International Society of Limb Salvage evaluation system and 80 by the Hospital for Special Surgery Knee Score system. This implant is a promising choice for joint reconstruction after excision of tumors at the knee joint.

Relationship between magnitude of resection, complication, and prosthetic survival after prosthetic knee reconstructions for distal femoral tumors.

Limb‐sparing surgery has become the preferred surgical treatment of malignant bone tumors. The objective of this study was to evaluate factors that influence the morbidity and outcome of prosthetic knee replacement after resection of malignant tumors of the distal femur.

Expression of epidermal growth factor receptor, ERBB2 and KIT in adult soft tissue sarcomas : A clinicopathologic study of 281 cases

Little is known about the expression of receptor tyrosine kinases in adult soft tissue sarcomas (STS). In the current study, the authors analyzed the expression of epidermal growth factor receptor (EGFR), ERBB2, and KIT in 281 patients with STS who were treated in a single institution. Verification of the presence of an association with prognosis was performed.

Pelvic ring reconstruction with the double- barreled vascularized fibular free flap

Background: Although hemipelvectomy has been the standard treatment for malignant tumors of the pelvis, limb salvage surgery is now the treatment of choice, even for patients with advanced tumors. For these patients, pelvic reconstruction is needed to maintain the stability of the pelvis and the spinal column and to allow ambulation. In this report, the authors’ experiences with pelvic ring reconstruction are described. Methods: Pelvic ring reconstruction with free double-barreled vascularized fibular grafts was performed after resection of malignant pelvic tumors in five patients. The graft was fixed with a fixation plate and screws in three patients and with the Cotrel-Dubousset rod system in two patients. After surgery, perioperative and postoperative findings were evaluated. Results: In one patient, a pedicled rectus abdominis musculocutaneous flap was transferred to repair defects of the skin and underlying soft tissue. The free fibular graft was transferred successfully in four of five patients; however, the graft was removed in one patient because of infection with methicillin-resistant Staphylococcus aureus. After surgery, three of the four patients with successful grafts could walk with full weight bearing and without a cane; the fourth patient died as a result of multiple metastases to the lung before walking was attempted. Conclusions: The double-barreled fibular graft is well vascularized and can achieve satisfactory bone union. It is a safe and effective method for reconstructing the pelvic ring. Furthermore, the Cotrel-Dubousset rod system can provide rigid fixation soon after surgery and is useful for early rehabilitation of walking.

Staging performance of carbon-11 choline positron emission tomography/computed tomography in patients with bone and soft tissue sarcoma: comparison with conventional imaging.

The present study was conducted to compare the diagnostic accuracy between carbon‐11 choline (11C‐choline) positron emission tomography (PET)/computed tomography (CT) and conventional imaging for the staging of bone and soft tissue sarcomas. Sixteen patients who underwent 11C‐choline PET/CT prior to treatment were evaluated retrospectively for staging accuracy. Conventional imaging methods consisted of 99,mTc‐hydroxymethylene diphosphonate bone scintigraphy, chest CT and magnetic resonance imaging of the primary site. The images were reviewed and a consensus was reached by two board‐certified radiologists who were unaware of any clinical or radiological information using hard‐copy films and multimodality computer platform. Tumor stage was confirmed by histological examination and/or by an obvious progression in number and/or size of the lesions on follow‐up examinations. Reviewers examining both 11C‐choline PET/CT and conventional imaging classified T stage in all patients. Interpretation based on 11C‐choline PET/CT, the Node (N) stage was correctly diagnosed in all patients, whereas the accuracy of conventional imaging in N stage was 63%. Tumor Node Metastasis (TNM) stage was assessed correctly with 11C‐choline PET/CT in 15 of 16 patients (94%) and with conventional imaging in eight of 16 patients (50%). The overall TNM staging and N staging accuracy of 11C‐choline PET/CT were significantly higher than that of conventional imaging (P < 0.05). 11C‐choline PET/CT is more accurate than conventional imaging regarding clinical staging of patients with bone and soft tissue sarcomas. A whole body 11C‐choline PET/CT might be acceptable for imaging studies of tumor staging prior to treatment. (Cancer Sci 2006; 97: 1125–1128)

Bilateral adrenal gland metastasis from malignant fibrous histiocytoma : Value of [F-18]FDG PET-CT for diagnosis of occult metastases

The vast majority of soft tissue sarcomas metastasize initially to the lungs. We report a 71-year-old woman with malignant fibrous histiocytoma of the right buttock and thigh that metastasized to the bilateral adrenal glands without development of pulmonary metastasis. Whole-body [F-18]FDG PET-CT showed abnormal tracer uptakes in the bilateral adrenal glands in addition to high accumulation in the primary soft tissue tumors. CT-guided needle biopsy revealed that both of the adrenal lesions were metastatic malignant fibrous histiocytoma. There was no pulmonary or other visceral metastasis. To the authors’ knowledge, this is the first report of malignant fibrous histiocytoma metastatic to the bilateral adrenal glands without development of pulmonary metastases. This case illustrates the excellence of [F-18]FDG PET-CT scan for diagnosis of occult metastases from soft tissue sarcomas.

Carotid body paraganglioma metastatic to bone: report of two cases

Abstract Two patients with carotid body paraganglioma developed bone metastases 3 and 6 years respectively after surgical excision of the primary tumors. Plain radiographs showed ill-defined metastatic lesions. Scintigram using radiolabeled metaiodobenzylguanidine, an analogue of noradrenaline that is taken up by neurosecretary granules, showed an abnormal accumulation in the corresponding metastatic lesion. Histologically, nests of epithelioid cells with clear cytoplasm and pyknotic nuclei and abundant collagen fibers were observed within destroyed trabeculae. Treatment including external radiation and surgery provided pain relief and early local disease control.