L-[1-11C]-tyrosine PET to evaluate response to hyperthermic isolated limb perfusion for locally advanced soft-tissue sarcoma and skin cancer.
PET with L-[1-11C]-tyrosine (TYR) was investigated in patients undergoing hyperthermic isolated limb perfusion (HILP) with recombinant tumor necrosis factor alpha (rTNF-alpha) and melphalan for locally advanced soft-tissue sarcoma and skin cancer of the lower limb. METHODS: Seventeen patients (5 women, 12 men; age range 24-75 y; mean age 52 y) were studied. TYR PET studies were performed before HILP and 2 and 8 wk afterwards. The protein synthesis rates (PSRs) in nanomoles per milliliter per minute were calculated. After final PET studies, tumors were resected and pathologically examined. Patients with pathologically complete responses (pCR) showed no viable tumors after treatment. Those with pathologically partial responses (pPR) showed various amounts of viable tumors in the resected tumor specimens. RESULTS: Six patients (35%) showed a pCR and 11 patients (65%) showed a pPR. All tumors were depicted as hot spots on PET studies before HILP. The PSR in the pCR group at 2 and 8 wk after perfusion had decreased significantly (P < 0.05) in comparison to the PSR before HILP. A significant difference was found in PSR between the pCR and pPR groups at 2 and at 8 wk (P < 0.05). Median PSR in nonviable tumor tissue was 0.62 and ranged from 0.22 to 0.91. With a threshold PSR of 0.91, sensitivity and specificity of TYR PET were 82% and 100%, respectively. The predictive value of a PSR > 0.91 for having viable tumor after HILP was 100%, whereas the predictive value of a PSR < or = 0.91 for having nonviable tumor tissue after HILP was 75%. The 2 patients in the pPR groups with a PSR < 0.91 showed microscopic islets of tumor cells surrounded by extensive necrosis on pathological examination. CONCLUSION: Based on the calculated PSR after HILP, TYR PET gave a good indication of the pathological outcome. Inflammatory tissue after treatment did not interfere with viable tumor on the images, suggesting that it may be worthwhile to pursue TYR PET in other therapy evaluation settings. (+info
FDG and L-[1-11C]-tyrosine imaging of soft-tissue tumors before and after therapy.
This study was undertaken to investigate the relationship of PET using fluorodeoxyglucose (FDG) or L-[1-11C]-tyrosine (TYR) with histopathologic findings in soft-tissue tumors, before and after therapy. Histopathologic parameters that were studied were tumor grade, mitotic rate, proliferation activity and amount of necrosis. METHODS: PET with either FDG or TYR was performed in 55 patients with a lesion suspected to be a malignant soft-tissue tumor. In 28 patients, a second PET study was performed after therapy. Metabolic rate of glucose consumption (MRglc) and protein synthesis rate (PSR) were calculated. Histologic parameters were obtained from a biopsy specimen that was taken just after the first PET study and from the tumor remnant that was resected after therapy. RESULTS: MRglc correlated with tumor grade (r = 0.71) and mitotic rate (r = 0.68) but not with proliferation or necrosis. After therapy, there was no longer a correlation with mitotic rate. PSR correlated with tumor grade (r = 0.53), mitotic rate (r = 0.73) and proliferation (r = 0.66). After therapy, correlation with mitosis and proliferation had improved, and a negative correlation was found between PSR and necrosis (r = -0.74). CONCLUSION: These results validate the use of both FDG and TYR to give an in vivo indication of histologic tumor parameters. However, FDG gives a better indication of tumor grade, whereas TYR is more accurate in predicting mitotic rate and proliferation, especially after therapy. FDG may therefore not be the most suited tracer for monitoring therapy. TYR might be more appropriate for that purpose. (+info
Subcutaneous sacrococcygeal myxopapillary ependymoma.
We report a case of myxopapillary ependymoma presenting as a primary tumor of the subcutaneous tissue in the sacrococcygeal region. The mass was large, well-encapsulated, lobulated, and multiseptated, with varying signal intensity on T1- and T2-weighted MR images caused by hemorrhagic necrosis, blood degradation products, and calcification. Only a small viable portion enhanced after administration of contrast material. Multiple lobules formed from fibrous septa and dystrophic calcification also characterize this tumor. (+info
Lymphangiosarcomas in cats: a retrospective study of 12 cases.
Clinical, macroscopic, and histologic features of 12 lymphangiosarcomas in cats are described. Nine tumors were located in the subcutaneous tissue at the caudoventral abdominal wall (eight cats) or in the neck (one cat). The remaining three cats had lymphangiosarcomas around the cranial mesenteric artery (two cats) or precardial in the mediastinum (one cat). Macroscopically, the tumors were noncircumscribed, white, edematous, and intermixed with fat tissue. Histologic features varied from cleft-forming and cavernous growth to papilliform and solid patterns. Follow-up data were available for seven cats with subcutaneous lymphangiosarcomas. All these cats died or were euthanatized within 6 months after surgery because of poor wound healing, local recurrence, or distant metastases. The cats with abdominal or thoracic masses were either euthanatized at surgery or within 6 months after the first surgery because of recurrent chylothorax, chyloperitoneum, or distant metastases. (+info
Clinical and radiological aspects of idiopathic diabetic muscle infarction. Rational approach to diagnosis and treatment.
The systemic effects of diabetes mellitus are well recognised. The heart, kidney, central and peripheral nervous systems, and the distal parts of the limbs are often the site of end-organ damage resulting from ischaemia. Infarction of large muscle groups in the limb, not associated with gangrene, is uncommon. There have been few reported cases other than radiological descriptions of diabetic muscle infarcts. While previous reports have illustrated some of the clinical and radiological characteristics of this condition, the paucity of published cases makes it difficult to determine the most appropriate methods of diagnosis and treatment. During a five-year period we treated 14 patients with diabetes mellitus, aged from 32 to 59 years, who were referred to a musculoskeletal oncology service for suspected soft-tissue sarcoma, but were subsequently found to have a diabetic muscle infarct. Closed needle biopsy was performed in 13 without complications. In 12 patients, the symptoms resolved without surgical treatment. (+info
Color Doppler sonography of focal lesions of the skin and subcutaneous tissue.
We evaluated with color Doppler sonography 71 visible and palpable nodules of the skin and subcutaneous tissue from 51 patients. The nodules were classified as avascular (type I), hypovascular with a single vascular pole (type II), hypervascular with multiple peripheral poles (type III), and hypervascular with internal vessels (type IV). Of the 32 malignant nodules, 9% showed a type I pattern, 50% had a type III pattern, and 41% had a type IV pattern; of the 39 benign nodules, 86% showed a type I pattern and 14% had a type II pattern. The sensitivity and specificity of hypervascularity in malignant lesions were 90% and 100%, respectively, whereas the sensitivity and specificity of hypovascularity in benign lesions were 100% and 90%, respectively. The authors conclude that color Doppler sonography is able to increase the specificity of ultrasonography in the evaluation of nodular lesions of the skin. (+info
Pulmonary metastases from soft tissue sarcoma: analysis of patterns of diseases and postmetastasis survival.
OBJECTIVE: To report the patterns of disease and postmetastasis survival for patients with pulmonary metastases from soft tissue sarcoma in a large group of patients treated at a single institution. Clinical factors that influence postmetastasis survival are analyzed. SUMMARY BACKGROUND DATA: For patients with soft tissue sarcoma, the lungs are the most common site of metastatic disease. Although pulmonary metastases most commonly arise from primary tumors in the extremities, they may arise from almost any primary site or histology. To date, resection of disease has been the only effective therapy for metastatic sarcoma. METHODS: From July 1982 to February 1997, 3149 adult patients with soft tissue sarcoma were admitted and treated at Memorial Sloan-Kettering Cancer Center. During this interval, 719 patients either developed or presented with lung metastases. Patients were treated with resection of metastatic disease whenever possible. Disease-specific survival was the endpoint of the study. Time to death was modeled using the method of Kaplan and Meier. The association of factors to time-to-event endpoints was analyzed using the log-rank test for univariate analysis and the Cox proportional hazards model for multivariate analysis. RESULTS: The overall median survival from diagnosis of pulmonary metastasis for all patients was 15 months. The 3-year actuarial survival rate was 25%. The ability to resect all metastatic disease completely was the most important prognostic factor for survival. Patients treated with complete resection had a median survival of 33 months and a 3-year actuarial survival rate of 46%. For patients treated with nonoperative therapy, the median survival was 11 months. A disease-free interval of more than 12 months before the development of metastases was also a favorable prognostic factor. Unfavorable factors included the histologic variants of liposarcoma and malignant peripheral nerve tumors and patient age older than 50 years at the time of treatment of metastasis. CONCLUSIONS: Resection of metastatic disease is the single most important factor that determines outcome in these patients. Long-term survival is possible in selected patients, particularly when recurrent pulmonary disease is resected. Surgical excision should remain the treatment of choice for metastases of soft tissue sarcoma to the lung. (+info
The enigma of desmoid tumors.
OBJECTIVE: To analyze patients with recurrent extremity desmoids, in whom the surgical therapeutic option was either major amputation or observation. SUMMARY BACKGROUND DATA: The biology and natural history of desmoid tumors are an enigma. These tumors invade surrounding structures and recur locally but do not metastasize. The morbidity of treating these tumors in the context of their relatively benign biology is uncertain. METHODS: Between July 1982 and June 1998, the authors treated and prospectively followed 206 patients with extremity desmoid tumors. All patients underwent standardized surgical resection, the surgical goal always being complete resection with negative margins. When tumors recurred, they were evaluated for reresection. Amputation was considered when resection was not possible because of neurovascular or major bone involvement, or in the presence of a functionless, painful extremity. RESULTS: During this period, 22 patients had disease that was not resectable without amputation. This was out of a total of 115 patients with primary disease and 91 patients with recurrent disease. All recurrences were local; in no patient did metastasis develop. In this group of 22 patients with unresectable disease, 7 underwent amputation and 15 did not. These 15 patients were followed, alive with disease, having no surgical resection. Four patients received systemic treatment with tamoxifen and nonsteroidal antiinflammatories, three received systemic cytotoxic chemotherapy, and two received both tamoxifen and chemotherapy. Six patients received no systemic treatment. The range of follow-up was 25 to 92 months. In all patients, there was no or insignificant tumor progression; in three patients who underwent observation alone, there was some regression of tumor. During follow-up, no patient has required subsequent amputation, and no patient has died from disease. CONCLUSIONS: In desmoid tumors, aggressive attempts at achieving negative resection margins may result in unnecessary morbidity. Function- and structure-preserving procedures should be the primary goal. In select patients, whose only option is amputation, it may be prudent to observe them with their limb and tumor intact. (+info