Winby York-Kwan Chen

High-Resolution Ultrasonography of Primary Peripheral Soft Tissue Lymphoma

The purpose of this study was to evaluate the appearance of primary peripheral soft tissue lymphoma on high‐resolution ultrasonography.

Comparison between F-18-FDG positron emission tomography and histology for the assessment of tumor necrosis rates in primary osteosarcoma

Background: The purpose of this prospective study was to identify if F‐18‐fluorodeoxy‐D‐glucose positron emission tomography (F‐18‐FDG PET) was a reliable noninvasive surrogate of histologic response in determining the efficacy of neoadjuvant chemotherapy before surgical resection in primary osteosarcoma. Methods: Between January 2003 and December 2003, 10 patients with primary osteosarcomas were examined using F‐18‐FDG PET before neoadjuvant chemotherapy and surgery. The mean age at the time of first intervention was 19 years (range, 4‐47 years). Positive prognostic significance was defined as more than 90% tumor necrosis response following neoadjuvant chemotherapy. The parameters of FDG uptake were correlated with histologic findings. The intraclass correlation coefficient was used to validate the tumor necrosis rates determined by PET and histology. Results: The tumor necrosis rate determined by PET was comparable with that determined histologically. The mean standardized uptake value before and following neoadjuvant chemotherapy were 8.2 and 4.4, respectively. The average tumor necrosis rate determined by PET was 22%. However, the mean tumor necrosis rate determined histologically was 54.5%. According to the intraclass correlation coefficient models, the intraclass correlation coefficient equaled 0. The relationship of tumor necrosis rates determined by F‐18‐FDG PET and histology seems to be statistically insignificant. Conclusion: In this preliminary study, FDG PET did not seem to be a promising tool for evaluating the response of primary osteosarcoma to neoadjuvant chemotherapy.

Treatment of Focal Cerebral Ischemia with Liposomal Nerve Growth Factor

Liposomal nerve growth factor (NGF) was used for the treatment of focal cerebral ischemia in a rat model. Positive charge inducing agents of sphingosine (SP) and stearylamine (S) were formulated in the liposomal NGF. Dose-response of intraventricular injection of liposomal NGF showed significant reduction in infarct volume at the dose of 5 and 10 μ g/rat of NGF. The liposomal NGF formulated with SP or S demonstrated similar results in the reduction of total infarct volume in rats. When we increased the molar ratio of SP and S from 0.15 to 0.3, the infarct volume from rats showed a similar value as that of the control treated with NGF solution. Liposomal NGF was given prior to the development of ischemia. We found that NGF was effective in prevention of neuronal death. The NGF concentrations in brain for liposomal NGF were maintained in a level significantly higher than those for NGF solution. This was attributed to the positively charged liposomal NGF bound effectively in brain ventricle and caused longer retention time than free NGF for localization in brain. Therefore, the effect of liposomal NGF on reduction of infarct volume was significant. We assumed that the transportation of NGF might go through the cerebrospinal fluid pathway throughout the ventricular system and subarachnoid system to cerebral cortex to produce a therapeutic effect on ischemia.

Primary leiomyosarcoma of bone

Abstract. We report a case of primary leiomyosarcoma in the right femoral diaphysis. Conventional radiographs revealed an indistinct osteolytic lesion with a very subtle periosteal reaction. MR imaging revealed an intramedullary lesion with a well-defined margin, cortical breakthrough and soft tissue extension. The lesion was isointense relative to muscle on T1-weighted imaging, iso-hypointense relative to fat on fast spin echo T2-weighted imaging, and hyperintense to muscle on fast spin echo T2-weighted imaging with fat saturation. A peripheral rim and intratumoral spoke-wheel-like enhancement in the soft tissue component of the tumor was noted on gadolinium-enhanced T1-weighted imaging with fat saturation. Such an enhancing pattern, which has not been described in the literature previously but has been seen in leiomyosarcomas elsewhere by both MR imaging and computed tomography, deserves further pathological correlation.

Sonographic findings in skeletal muscle metastasis from renal cell carcinoma.

The skeletal muscle is an unusual site of metastasis for renal cell carcinoma (RCC). In large autopsy series, only 0.4% of patients with RCC had skeletal metastases. Renal cell carcinoma metastasis can occur late in the course of the disease, creating a diagnostic challenge. In this report, we describe a patient with skeletal muscle metastasis from RCC that appeared 14 years after nephrectomy. We describe the sonographic findings, which, to our knowledge, have not been previously reported.

Orbital Metastatic Osteosarcoma

A 15-year-old girl with right tibial osteosarcoma, diagnosed 22 months previously, developed right orbital and skull base metastases, with symptoms including painful protrusion of the right eyeball and severe visual impairment. She underwent embolization of the metastatic tumor, local irradiation, and chemotherapy followed by intralesional resection of the mass because extensive involvement of the skull base precluded complete surgical resection. The best corrected visual acuity in her right eye initially decreased to 20/200, then dropped to no light perception after embolization, and then improved to counting fingers at 50 cm after radiotherapy. The symptoms of pain and proptosis subsided completely. After 24 months of follow-up from the presentation of orbital metastasis, the patients right-eye vision remained unchanged. The surgical specimen revealed a necrotic tumor similar to osteosarcoma. In conclusion, orbital metastasis of osteosarcoma is rare, but may lead to severe visual impairment. Combined radiotherapy, chemotherapy and surgery can partially relieve symptoms, but cannot completely eradicate the tumors.

Extraosseous Osteogenic Sarcoma

Extraosseous osteogenic sarcoma is a very rare malignant neoplasm. Out of the more than 400 cases of soft tissue sarcomas on file in our hospital, only 2 were extraosseous osteogenic sarcomas. Both were situated in the thigh. The first case was initially diagnosed as a hematoma and treated by marginal excision. The diagnosis of high-grade osteosarcoma primarily arising in soft tissue was made from histopathologic examination. Radiotherapy of 60 Gy in 30 fractions was given postoperatively. The second patient, primarily diagnosed as having a soft tissue sarcoma, was treated by wide excision. The final pathologic report was high-grade extraosseous osteogenic sarcoma. Adjuvant chemotherapy was given postoperatively. Both patients are alive without local recurrence and distant metastasis at postoperative 90-month and 107-month follow-up, respectively.

Soft-tissue Tumor Differentiation Using 3D Power Doppler Ultrasonography With Echo-contrast Medium Injection

Background: We aimed to evaluate the ability of 3‐dimensional power Doppler ultrasonography to differentiate soft‐tissue masses from blood flow and vascularization with contrast medium. Methods: Twenty‐five patients (mean age, 44.1 years; range, 12‐77 years) with a palpable mass were enrolled in this study. Volume data were acquired using linear and convex 3‐dimensional probes and contrast medium injected manually by bolus. Data were stored and traced slice by slice for 12 slices. All patients were scanned by the same senior sonologist. The vascular index (VI), flow index (FI), and vascular‐flow index (VFI) were automatically calculated after the tumor was completely traced. All tumors were later confirmed by pathology. Results: The study included 8 benign (mean, 36.5 mL; range, 2.4‐124 mL) and 17 malignant (mean, 319.4 mL; range, 9.9‐1,179.6 mL) tumors. Before contrast medium injection, mean VI, FI and VFI were, respectively, 3.22, 32.26 and 1.07 in benign tumors, and 1.97, 29.33 and 0.67 in malignant tumors. After contrast medium injection, they were, respectively, 20.85, 37.33 and 8.52 in benign tumors, and 40.12, 41.21 and 17.77 in malignant tumors. The mean differences between with and without contrast injection for VI, FI and VFI were, respectively, 17.63, 5.07 and 7.45 in benign tumors, and 38.15, 11.88 and 16.55 in malignant tumors. Tumor volume, VI, FI and VFI were not significantly different between benign and malignant tumors before and after echo‐contrast medium injection. However, VI, FI and VFI under self‐differentiation (differences between with and without contrast injection) were significantly different between malignant and benign tumors. Conclusion: Three‐dimensional power Doppler ultrasound is a valuable tool for differential diagnosis of soft‐tissue tumors, especially with the injection of an echo‐contrast medium.

Malignant Ganglioneuroma Arising from Mediastinal Mixed Germ Cell Tumor

Mixed germ cell tumors with non-germ cell malignant components rarely occur in the anterior mediastinum. We report a case of a 34-year-old man who presented with an anterior mediastinum mass. Mixed germ cell tumor was initially diagnosed based on the pathologic findings of germinoma on thoracoscopic biopsy and clinical findings of elevated serum alpha-fetoprotein and beta-human chorionic gonadotropin. The patient received preoperative chemotherapy and subsequent complete resection of the residual tumor. Pathologic examination of the excised specimen showed predominantly malignant ganglioneuroma and small residual foci of teratoma. To our knowledge, this is the first reported case of a malignant ganglioneuroma arising from mediastinal mixed germ cell tumor.

Allograft Arthrodesis of the Knee in High-grade Osteosarcoma

Background: A retrospective cohort study was conducted to evaluate the outcomes of massive allograft arthrodesis in the management of high‐grade osteosarcoma around the knee. Methods: The results of 19 patients with high‐grade osteosarcoma around the knee, which was treated by wide resection and reconstruction using allograft arthrodesis, were evaluated for a mean length of 7.3 years (range, 3–13 years). The mean age at the time of surgery was 13.3 years (range, 6–27 years). According to the Musculoskeletal Tumor Society staging system, 17 patients were stage IIB and 2 were stage IIIB at presentation. Evaluations were based on the oncologic results, non‐oncologic results and complications. Functional evaluation was performed with the Enneking functional evaluation form. Results: Four patients (21.1%) died of their disease; 3 (15.8%) are alive with disease; and 12 (63.2%) are free of disease. Four patients (21.1%) had local recurrence of their tumor at a mean of 23 months postoperatively (range, 9–44 months). The mean time to union of the metaphyseal junction was 24.7 weeks (range, 16–30 weeks) and the diaphyseal junction was 47 weeks (range, 24–78 weeks). The overall complication rate was 31.6%, including 2 (10.5%) infections, 3 (15.8%) allograft fractures, and 1 (5.3%) nonunion. Our mean final functional result was 65%. Conclusion: Due to the high rate of complications in this study, we conclude that allograft arthrodesis should be left as a salvage or “back‐up” reconstructive procedure after resection of osteosarcoma around the knee, unless there are special indications for this procedure. We found allograft fracture to be the most common complication.