Spinal metastases from myxoid liposarcoma warrant screening with magnetic resonance imaging

BACKGROUND

Myxoid liposarcoma (MLS) has an unusual tendency for extrapulmonary metastasis, particularly to the spine and soft tissues. The objective of this study was to determine the prevalence of spinal metastasis, treatment outcomes, and optimal screening method for spinal metastasis in patients with MLS.

METHODS

Data from patients with had spinal metastases were obtained from the authors' institutional soft tissue sarcoma database. The accuracy with which positron emission tomography (PET) scans and bone scans identified metastatic lesions was compared with the accuracy of magnetic resonance imaging (MRI). Clinical response to treatment was based on pain, neurologic scores, and survivorship analysis.

RESULTS

There were 33 patients who developed spinal metastasis after a median 36 months of follow-up (range, from 7.5 months to 33 years). Known spinal metastases were detected by bone scans in 16% of patients and by PET scans in 14% of patients. Patients who underwent surgery had high-grade spinal cord compression more often than patients who did not undergo surgery (72% vs 19%, respectively; P = .002). Pain and neurologic function were improved or maintained in all patients who received radiation alone (n = 8 patients) and in all but 1 patient who underwent surgery (n = 18 patients). The median overall survival was 51.4 months from the time of primary diagnosis and 21.9 months from the time of first metastasis.

CONCLUSIONS

Bone scans and PET scan lack sufficient sensitivity to detect spinal metastasis from MLS. Treatment of metastasis is palliative, but local treatment can yield long-term disease control in select patients. Screening with whole-spine MRI may lead to the earlier detection of spinal metastasis.

Influence of carboplatin infusion on osteosarcoma blood flow

PURPOSE

Herein we report that carboplatin infusion influenced tumor blood flow signal independent of the mechanical decompression induced by the artificial lymphatics system technology that was being evaluated as part of a randomized veterinary clinical trial, treating spontaneously occurring canine appendicular osteosarcoma, a tumor very similar to its human counterpart.

METHODS

Blood flow within the central region of the tumor was recorded continuously using laser Doppler flowmetry, a real-time measurement technology. Time-averaged flow values were computed from segments taken from the recordings immediately before starting carboplatin infusion, and during infusion.

RESULTS

Carboplatin increased the tumor blood flow signal by an additional 59 +/- 26% (mean +/- SEM; p = 0.06) over the increase induced by the decompression. The increase started within 49 +/- 46 s after the start of infusion, had a response time constant of 19 +/- 21 s and persisted throughout the infusion, ending shortly after infusion ended.

CONCLUSION

The rapidity of the flow signal increase suggests that carboplatin may have an autonomic effect on circulation, either local or systemic. The observations identify a new action of this drug and suggest a possible mechanism to exploit therapeutically.

Over-expression of parathyroid hormone Type 1 receptor confers an aggressive phenotype in osteosarcoma

Osteosarcoma is the most common primary bone malignancy in children and is associated with rapid bone growth. Parathyroid hormone-related peptide (PTHrP) signaling via parathyroid hormone Type 1 receptor (PTHR1) is important for skeletal development and is involved in bone metastases in other tumors. The aim of this study was to investigate the status of PTHrP/PTHR1 and its possible role in osteosarcoma. In a preliminary screening, a higher level of PTHR1 mRNA, but not PTHrP, was found in 4 osteosarcoma xenografts as compared with 4 standard cell lines, or 5 patient derived cell lines (p < 0.05) using quantitative RT-PCR. It was therefore extended to 55 patient specimens, in which a significantly higher level of PTHR1 mRNA was detected in metastatic or relapsed samples than those from primary sites (p < 0.01). Cell behavior caused by PTHR1 overexpression was further studied in vitro using PTHR1 transfected HOS cell line as a model. Over-expression of PHTR1 resulted in increased proliferation, motility and Matrigel invasion without addition of exogenous PTHrP suggesting an autocrine effect. Importantly, the aggressiveness in PTHR1-expressing cells was completely reversed by RNAi mediated gene knockdown. In addition, PTHR1 over-expression led to delayed osteoblastic differentiation and upregulation of genes involved in extracellular matrix production, such as TGF-beta1 and connective tissue growth factor. When cocultured with bone marrow derived monocytes, PTHR1 transfected HOS cells induced a greater number of osteoclasts. This study suggests that PTHR1 over-expression may promote osteosarcoma progression by conferring a more aggressive phenotype, and forming a more favorable microenvironment.

Bone cancer

Primary bone cancers are extremely rare neoplasms, accounting for less than 0.2% of all cancers. Primary bone cancers show wide clinical heterogeneity and, perhaps most importantly, are often curable. With current multimodality treatment, including multi-agent chemotherapy, approximately three quarters of all patients diagnosed with osteosarcoma are cured. Updates for 2007 include changes in recommendations for treating chondrosarcoma, Ewing's sarcoma, and osteosarcoma.

For the most recent version of the guidelines, please visit NCCN.org

What is quality of life in children with bone sarcoma?

Quality of life measures have neglected to include a critical self-assessment component in pediatric sarcoma patients. Our report shows how children rate their own quality of life and how that varies over time after surgery. Using the Pediatric Outcomes Data Collection Instrument, quality of life data was prospectively collected and combined with a retrospective review of clinical parameters on 43 children with primary bone sarcoma, with an average followup of 3 years. Children reported good yet variable scores in five of the six domains. Lower scores were noted in the Sports/Physical Functioning domain, particularly in the first 12 months after surgery, with improvement seen up to 24 months after surgery. Tumor specific factors such as size larger than 8 cm and lower extremity location were negative predictors for Sports/Physical Functioning. The only demographic factor that predicted perceived quality of life scores was gender, with girls reporting lower scores in Sports/Physical Functioning, Pain/Comfort, and Global Functioning domains. The Pediatric Outcomes Data Collection Instrument gives discriminatory detailed textured evaluation of the outcome of children treated for skeletal sarcoma. Further development of quality of life measures is needed to allow its use in treatment selection.

Coaxial extendible knee equalizes limb length in children with osteogenic sarcoma

We assessed our ability to achieve limb length equality (LLE) in children following limb-sparing surgery for distal femur osteogenic sarcoma using coaxial extendible prostheses in 12 children, averaging 11.6 years old at the time of tumor resection (range, 5.9-15.5 years). All but one child achieved clinical limb length equality. There were 23 extensions, averaging 3.8 extensions per patient (range, 1-5), by an average 13 mm per extension and an average total extension of 49.3 mm per patient extended. Eight children underwent revision surgery after an average of 45.1 months (range, 3-115 months). Aseptic loosening occurred more frequently among children with greater femoral diameter growth. The overall prosthetic survival was 60% at 3 years and 35% at 5 years. The survival until aseptic loosening at 3 and 5 years was 85% and 45%, respectively. Press-fit components survived longer than cemented stems. None of the devices loosened. At skeletal maturity the MSTS functional scores averaged 25. Using a coaxial extendible implant, we efficiently achieved LLE in this population. Prosthetic revision was needed frequently. Younger age and longer resection percentages were associated with shorter prosthetic survival and higher revision/aseptic loosening rates. Femoral diameter growth may contribute to loosening. Early experience with this extendible implant is promising.

Use of an artificial lymphatic system during carboplatin infusion to improve canine osteosarcoma blood flow and clinical response

BACKGROUND

The artificial lymphatic system (ALS), a mechanical system designed to reduce increased interstitial fluid pressure in solid tumors and enhance the delivery of chemotherapy, was evaluated within a randomized clinical trial treating spontaneously occurring canine appendicular osteosarcoma (OS), a tumor similar to its human OS counterpart.

METHODS

An ALS was investigated for its ability to increase OS blood flow and increase uptake of intravenously administered carboplatin.

RESULTS

Blood flow increased by 314% in tumors with active ALS drains versus 126% in control tumors (P < .03). Tumor carboplatin uptake increased by 51% after drain activation (P = .07). Microvascular density (MVD) was measured in tumors after surgical amputation and in corresponding bone regions in a cohort of normal dogs. The OS tumors had equivalent MVD as normal bone, and MVD was higher in the humerus than the femur (P < .03) in both tumor and normal bone. Median survival between the ALS-treated and control cohorts was not different despite increased drug uptake or ALS manipulation. Compared with historic controls, ALS drain insertion into tumors to reduce interstitial fluid pressure did not worsen the prognosis.

CONCLUSIONS

The findings in canine spontaneously occurring OS indicate that an ALS may be of value as a chemotherapy adjunct for enhancing the delivery of chemotherapy to tumor interstitium.

The Folate Receptor α Is Frequently Overexpressed in Osteosarcoma Samples and Plays a Role in the Uptake of the Physiologic Substrate 5-Methyltetrahydrofolate

PURPOSE

Two major systems exist for folate cell entry: the reduced folate carrier (RFC) and the folate receptor (FR). Although defective RFC-mediated transport was frequently identified as a mechanism of methotrexate (MTX) resistance in osteosarcoma, the status of FR and its role in this disease are unknown.

EXPERIMENTAL DESIGN

mRNA for FR alpha was measured in 107 osteosarcoma specimens using quantitative reverse transcription-PCR and was related to RFC expression. The effect of FR alpha overexpression on MTX resistance and natural folate uptake was studied using FR alpha non-expressing osteosarcoma 143B cells transfected with FR alpha cDNA in comparison with those transfected with sense or antisense RFC in the same genetic background.

RESULTS

Eighty-four samples (78.5%) had detectable FR alpha mRNA, and 29.9% had higher levels than the ovarian cancer cell line SKOV-3. No correlation was found between mRNA levels of FR alpha and RFC (r(2)=0.002). FR alpha overexpression had minor effects on the transport of MTX and sensitivity to this drug. Among the transfected 143B sublines, only the 143B-FR alpha was able to uptake 5-methyltetrahydrofolate when the extracellular concentration was reduced to 2 nmol/L, which conferred a growth advantage in physiologic folate concentrations compared with vector-only-transfected cells. Importantly, this was not similarly achieved by RFC overexpression.

CONCLUSIONS

This study suggests that FR alpha plays a role in the uptake of 5-methyltetrahydrofolate when the concentration gradient is insufficient for RFC-mediated transport. FR alpha overexpression is unlikely secondary to the decreased RFC expression in osteosarcoma.

Low-grade myxofibrosarcoma: CT and MRI patterns in recurrent disease

OBJECTIVE

Low-grade myxofibrosarcoma often relentlessly recurs after surgical resection, with an unusual infiltrative growth pattern and sometimes without a discrete tumor nodule at pathologic examination. This study was undertaken to determine and show patterns of recurrent low-grade myxofibrosarcoma at CT and MRI.

CONCLUSION

Unlike in most other histologic types of low-grade soft-tissue sarcoma, recurrent low-grade myxofibrosarcoma often is infiltrative; shows a tapering, tail-like margin and superficial spreading configuration; and metastasizes to various distant sites, including lungs, pleura, bone, adrenal gland, soft tissue, and mesentery. Knowledge of these unusual characteristics is important in assessing the presence and extent of recurrent low-grade myxofibrosarcoma before surgical reexcision.

Skeletal metastases in myxoid liposarcoma: an unusual pattern of distant spread

BACKGROUND

Myxoid liposarcoma (MLS), the second most common subtype of liposarcoma, occurs predominantly in the extremities of young adults and has a disproportionately high tendency to metastasize to unusual soft tissue locations, before disseminated spread or pulmonary metastases. Anecdotal evidence, mainly supported by isolated case reports, suggests that a subset of these patients also develop bone metastasis, especially within the spine, which was previously under-appreciated.

STUDY DESIGN

In this study we investigate the incidence of osseous metastases in a well annotated sarcoma database and correlate this endpoint with clinicopathologic and molecular findings.

RESULTS

From a total of 230 patients with MLS diagnosis confirmed histologically, who were managed and followed prospectively at MSKCC, 40 (17%) developed skeletal metastases, comprising 56% of all metastatic events. A significant number of these bone metastases were identified early in the disease course, before the manifestation of disease in sites where sarcomas usually metastasize, such as lung. From the time of 1st metastasis, the 5 years median survival was 16%. The majority (78%) of MLS patients developing bone metastases had a histologic high grade primary tumor. The median overall survival for the high grade tumors was 55 months, as compared to 105 months for low grade cases. Eleven (84%) of 13 cases tested by RT-PCR demonstrated a type II TLS-CHOP fusion transcript.

CONCLUSION

These findings suggest that MLS has a high incidence of osseous metastases, with predilection to spine, and often associated with the most common type of TLS-CHOP transcript. Screening should include images of the spine in high-risk MLS patients to exclude spinal metastases.

Treatment algorithm for locally recurrent osteosarcoma based on local disease-free interval and the presence of lung metastasis

BACKGROUND

Local recurrence in osteosarcoma is clinically distinct from metastasis, although associated with a similar reduction in survival. The prognostic factors in locally recurrent osteosarcoma were investigated and these factors were translated into a management strategy.

METHODS

In all, 407 consecutive patients with skeletal osteosarcoma between 1977 and 2002 were analyzed. Twenty-three patients with resectable local recurrence were analyzed. Clinical and tumor-related factors were assessed for significance in relation to survival and a management strategy was formulated based on factors found to be independently significant for survival.

RESULTS

Seventeen of the 23 patients underwent primary resections and initial treatment, yielding an overall local recurrence rate of 4.2% for resectable cancer. Median time to local recurrence was 13 months (95% confidence interval, 9-16 months). The 5-year and 10-year survival rates in the recurrent cases were 29% and 10%, respectively. All patients received chemotherapy both for their primary and recurrent disease. Increased risk of local recurrence (P < .0001) was strongly correlated with positive margins of resection. The rate of local recurrence was not related to chemotherapy-associated necrosis in the primary tumor. Nevertheless, neoadjuvant therapy halved the risk of local recurrence (odds ratio, 1.92; P = .3, power 10%). The strongest correlate with poor survival was local recurrence within the first year after primary resection (P = .001), followed by metastasis at the time of first local recurrence (P = .04) and failure to achieve clinical remission after disease recurrence (P = .04). Chemotherapy-associated necrosis and margins of resection of the primary tumor were not significant prognostic variables for survival. Survival differed significantly among patients defined by local disease-free interval and lung metastasis (P = .0001). They required an individualized approach as captured in the management algorithm.

CONCLUSION

There is a residual risk of local recurrence in patients despite favorable chemotherapy-associated necrosis and negative margins of resection. A treatment strategy emphasizing clinical remission at all identifiable sites offers the highest likelihood of survival in this patient population.

Function correlates with deltoid preservation in patients having scapular replacement

Advocates of scapular replacement suggest sparing the deltoid should be a prerequisite for use of a scapular prosthesis. We evaluated the importance of a functioning deltoid in scapular replacement for malignant tumors. We retrospectively reviewed 19 patients who received scapular prostheses after resection of a malignant tumor. The median followup was 18 months (range, 12-124 months). The axillary nerve was resected in eight patients and spared in 11 patients. The average International Society of Limb Salvage score was 25 of 30 points (range, 21-27 points). The average scores for patients with and without axillary nerve resection were 24 points (range, 21-25 points) and 26 points (range, 23-27 points), respectively. There was a difference between the two groups in hand positioning, overall function, and pain. However, there were no differences in emotional acceptance, lifting ability, or hand dexterity. We favor using a scapular prosthesis if there is a functioning deltoid; however resection of the deltoid should not be considered an absolute contraindication for scapular replacement.

Patellar complications following distal femoral replacement after bone tumor resection

BACKGROUND

Patellar complications following endoprosthetic reconstruction can occur as a result of anatomic, physiologic, and surgical reasons. Patellar impingement on tibial polyethylene is a complication of distal femoral replacement, and it is frequently related to inaccurate restoration of the joint line and to soft-tissue contracture. The purpose of our study was to determine the prevalence and type of patellar complications following distal femoral replacements after excisions of bone tumors.

METHODS

The results of reconstruction with use of a rotating-hinge endoprosthesis following excision of a distal femoral tumor in forty-three patients were retrospectively reviewed. Patients were followed clinically and radiographically for a minimum of forty-eight months or until death. Pain status, functional scores, and the range of motion were determined from a prospectively maintained database. The ratio of the patellar tendon length to the height of the patellar tendon insertion, as described by Insall and Salvati, was calculated. In addition, we attempted to determine whether the position of the patella was associated with anterior knee pain or with the functional scores derived with use of the International Society of Limb Salvage (ISOLS) scoring system.

RESULTS

Thirty-five patellar complications, including eleven cases of impingement, occurred in twenty-seven patients (63%). We found no difference, on the basis of our sample size, with regard to the presence of patellar pain, the range of motion, or the Insall-Salvati ratio between the patients with and those without impingement. The ratio of the patellar tendon length to the height of the patellar tendon insertion averaged 0.9 in the group with impingement and 1.4 in the group without impingement (p = 0.07). The ISOLS score averaged 21.2 points in the group with impingement compared with 24.2 points in the group without impingement (p = 0.01). Patella baja occurred in nine patients. The average ISOLS score (and standard deviation) was 20.1 +/- 4.4 points for the patients with patella baja compared with 24.8 +/- 3.9 points in the group with a normal patellar position (p = 0.004). Patellar fracture occurred in two patients, and osteonecrosis occurred in two patients. These patients were treated nonoperatively.

CONCLUSIONS

Patellar complications are common after distal femoral resection and endoprosthetic reconstruction. Patellar impingement on the polyethylene tibial bearing surface is a more common and important complication of distal femoral replacement than has been reported to date. Patella baja is also a relatively common complication, which has a negative impact on knee function.

Infiltrative MRI pattern and incomplete initial surgery compromise local control of myxofibrosarcoma

Myxofibrosarcoma (MFS) has a high local failure rate of up to 79%. We conducted a retrospective analysis on all patients with the diagnosis of myxofibrosarcoma seen between 1990 and 2004 to assess whether improved imaging with MRI reduced local recurrence, increased survival, and whether radiotherapy following resection influenced outcome. Twenty-one patients were treated for MFS with a median followup of 52 months (range, 18-122). All patients were surgically treated, with 19 receiving limb-sparing surgery. All patients with high grade disease, positive margins, or a pre-referral procedure received radiation therapy. The local recurrence rate was 57% for patients with a prior outside procedure (8 of 14), while patients with no prior surgery had a rate of 14% (1 of 7). Prior marginal excision and diffuse fascial spread on MRI predicted an increased local recurrence rate. The disease-free survival at 5 years was 43% (SE, 22%) for low-grade disease and 39% (SE, 18%) for high- grade disease. Magnetic resonance imaging observations suggest a unique pattern of diffuse spread along fascial planes that could be responsible for the high local recurrence. Radiation did not compensate for positive margins, nor did it reduce recurrence after negative margins.

LEVEL OF EVIDENCE

Therapeutic study, level IV (case series).

Sacral resection for recurrent rectal cancer: analysis of morbidity and treatment results

PURPOSE

Composite sacropelvic resection for locally advanced recurrent rectal cancer is a high-risk procedure that benefits select patients. We reviewed our recent institutional experience to evaluate case selection, morbidity, and outcomes.

METHODS

Between 1987 and 2004, 29 patients underwent composite resection for recurrent locoregional rectal cancer (17 females; median age, 60 years). Clinicopathologic indicators were evaluated as indicators of survival by log-rank test and Cox proportional hazards model.

RESULTS

Of 29 total patients, 27 (93 percent) received radiotherapy with their previous surgery (n = 10; 34 percent) or before sacrectomy (n = 17; 59 percent), and 12 (41 percent) received intraoperative therapy. Sacral resections were performed at S2/S3 (55 percent) or S4/S5 (45 percent) using anterior (41 percent) or combined anterior-posterior approach (59 percent), with adherence to (62 percent) or cortical invasion in (38 percent) the sacrum. A majority of those who had undergone previous abdominoperineal resection had total exenteration (9/13), whereas most patients who had undergone a previous sphincter-preserving procedure had abdominoperineal resection (12/16) and none had exenteration. Pedicle flaps (omental, 11; abdominal rectus, 7) often were used. A median of five (range, 1-33) units of blood was given intraoperatively. Transfusions were associated with previous abdominoperineal resection (P < 0.03), correlating strongly with postoperative morbidity (P < 0.02). There were 33 complications in 17 (59 percent) patients, most commonly perineal wound breakdown (9 (31 percent)) and pelvic abscess (5 (17 percent)). Median hospital stay was 18 (range, 7-56) days, significantly longer in patients with previous abdominoperineal resection (P < 0.02) or postoperative morbidity (P < 0.03). The only postoperative death was from pelvic sepsis. Resection was complete (R0) in 18 patients (62 percent), with microscopically positive margins (R1) in 10 (34 percent) and grossly positive margins (R2) in 1 (3 percent). Two-year and five-year recurrence rates were 47 and 85 percent, respectively; disease-specific survival was 63 and 20 percent, respectively. Less transfusion (P = 0.03), R0 resection (P = 0.005), lack of anterior organ involvement (P = 0.02), and absence of cortical bone invasion (P < 0.001) were associated with better survival on univariate analysis; original colorectal cancer stage was not.

CONCLUSIONS

Sacrectomy for rectal cancer is a high-risk procedure that can achieve clear resection margins with low mortality in select patients. This procedure has a low cure rate but may provide local disease control with acceptable morbidity.

The challenging role of radiation therapy for very young children with rhabdomyosarcoma

PURPOSE

To evaluate local control and toxicity for very young children treated with multimodality therapy for rhabdomyosarcoma (RMS).

METHODS AND MATERIALS

From 1990 to 2004, 20 patients<or=36 months at diagnosis were treated at our institution. Nineteen underwent chemotherapy (CMT), surgery and/or intraoperative high-dose-rate brachytherapy (IOHDR), and external-beam radiation (EBRT). Median age was 17 months. Sites included extremity (7), trunk (5), parameningeal (4), orbit (1), head/neck (1), bladder/prostate (1). Histologies consisted of 10 embryonal (53%) and 9 alveolar/undifferentiated (47%). Ten had delayed gross total resection (GTR) at median time of 17 weeks after the start of CMT, and 8 of these underwent IOHDR. Median interval between start of CMT and EBRT was 18 weeks. Median EBRT dose was 36 Gy. EBRT technique was either intensity-modulated (11), three-dimensional (3), or two-dimensional (5). Functional outcome was assessed for patients alive>or=1 year after diagnosis (15) in terms of mild, moderate, or severe deficits.

RESULTS

Median follow-up was 33 months for survivors and 23 months for all patients. Two-year actuarial local control, event-free survival, disease-specific survival, and overall survival were 84%, 52%, 74%, and 62%, respectively. All patients who began EBRT<or=18 weeks after the start of CMT had their disease controlled locally. Five have mild deficits and 10 have no deficits.

CONCLUSIONS

A reduced dose of 36-Gy EBRT after delayed GTR may maximize local control while minimizing long-term sequelae for very young children with RMS, but unresectable tumors (e.g., parameningeal) require higher doses. Normal-tissue-sparing techniques such as intensity-modulated radiation therapy and IOHDR are encouraged. Local control may be maximized when EBRT begins <or=18 weeks after initiation of CMT, but further study is warranted. Longer follow-up is required to determine the full extent of late effects.

Pigmented villonodular synovitis

Pigmented villonodular synovitis is a proliferative condition of the synovium. Monoarticular involvement, the most common process, occurs in two forms: localized and diffuse. The localized form is characterized by focal involvement of the synovium, with either nodular or pedunculated masses; the diffuse form affects virtually the entire synovium. The localized form has an excellent prognosis and a low recurrence rate when managed surgically. The more common diffuse form has a reported recurrence rate of up to 46%. Although the condition can present in any joint, the knee is the most commonly affected site. Pigmented villonodular synovitis is often aggressive, with marked extra-articular extension. Open synovectomy is the standard method of management. Arthroscopic synovectomy, which has gained popularity, has several advantages over the open technique, but it is associated with higher recurrence rates in diffuse pigmented villonodular synovitis. Synovectomy by any approach, however, may prevent secondary osteoarthritis and subsequent joint arthroplasty. Radiation-induced synovectomy has shown mixed results. Combined surgical and nonsurgical approaches may be necessary, and in some patients, total joint arthroplasty may be the only effective treatment.

Limb Salvage of Infected Knee Reconstructions for Cancer With Staged Revision and Free Tissue Transfer

Periprosthetic infections of oncologic reconstructions have an amputation rate between 37% and 87%. Eleven patients with an infected knee reconstruction following limb salvage surgery for cancer were treated with the staged protocol. All patients underwent prosthetic removal and implantation of an antibiotic-impregnated cement spacer, i.v. antibiotic therapy, repeat debridement and spacer change, and delayed prosthetic reconstruction and free tissue transfer. At the time of reconstruction, the median bone defect was 185 mm. The mean soft tissue defect was 112 cm2. Coverage was obtained with a free musculocutaneous flap. All limbs were spared without amputation or flap loss. The mean functional outcome as measured by the Musculoskeletal Tumor Society lower extremity score was 23 of 30. Infections of large prosthetic reconstructions about the knee can be salvaged successfully with repetitive debridement, staged prosthetic reimplantation, and free tissue transfer. Free tissue transfer improves the soft tissue envelope and allows restoration of joint motion.

LEVEL OF EVIDENCE

Case Series. Level IV.

Proximal deep vein thrombosis after hip replacement for oncologic indications

BACKGROUND

Patients with cancer who undergo surgery about the hip are at increased risk for the development of deep vein thrombosis. We implemented a program of chemical and mechanical prophylaxis to prevent this problem. This study was performed to assess the effectiveness of that program.

METHODS

Eighty-seven consecutive patients with an active malignant tumor who underwent hip replacement surgery at our institution over a two-year period were included in the study. All patients were treated with intermittent pneumatic compression devices. Seventy-eight patients received anticoagulants, and nine did not. Postoperative surveillance for proximal deep vein thrombosis was routinely performed on all patients with duplex Doppler ultrasonography.

RESULTS

Four patients had proximal deep vein thrombosis, and one patient, who did not receive anticoagulation, had a nonfatal pulmonary embolism. The use of prophylactic low-molecular-weight heparin (dalteparin) was associated with a 4% rate of proximal deep vein thrombosis (three of seventy-eight patients). Proximal deep vein thrombosis developed in three of eight patients with pelvic disease, one of nineteen patients with femoral disease, and zero of sixty patients with hip disease (p < 0.00001). The prevalence of proximal deep vein thrombosis was significantly higher (p < 0.02) following replacements in patients with sarcoma (three of twenty-one) than it was after replacements in patients with carcinoma (zero of fifty-seven) or hematologic malignant disease (one of nine). On multivariate analysis, only the location of the disease (the pelvis, femur, or hip) was found to be independently significant for an association with deep vein thrombosis. A wound complication developed in four of twenty-one patients with sarcoma and no patient with carcinoma or hematologic malignant disease (p < 0.001). The pathologic type was the only factor studied that was independently significant for an association with wound complications on multivariate analysis.

CONCLUSIONS

The rate of proximal deep vein thrombosis in patients who had undergone hip replacement for oncologic indications was low when the use of an intermittent pneumatic compression device was supplemented with prophylaxis with low-molecular-weight heparin.

Radiation therapy for Ewing’s sarcoma: Results from Memorial Sloan-Kettering in the modern era

PURPOSE

To evaluate the outcomes of patients with Ewing's sarcoma family of tumors (ESFT) treated with modern radiotherapy techniques with MRI along with optimal chemotherapy.

METHODS AND MATERIALS

The records of all 60 patients with ESFT who received radiation to the primary site between 1990 and 2004 were reviewed. All patients received chemotherapy, including vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide. Radiation was used as the sole modality for local control in 31 patients and was given either before (n=3) or after surgical resection (n=26) in the remainder. All patients had MRI and CT scan-based treatment planning, and 43% received intensity-modulated radiation therapy. Radiation doses ranged from 30 Gy to 60 Gy (median, 51 Gy), and 35% received hyperfractionated radiotherapy.

RESULTS

Median age was 16 years (range, 2-40 years). Because of selection bias for radiotherapy, the majority of primary tumors were centrally located (72%): spine (n=18), pelvis (n=15), extremities (n=12), chest wall (n=5), head and neck (n=5), and other (n=5). Thirty-eight percent of patients presented with metastatic disease, and 52% of primary tumors were >or=8 cm. Actuarial 3-year local control was 77%. The presence of metastases at diagnosis was an adverse prognostic factor for local control (84% vs. 61%, p=0.036). No other predictive factors for local failure were identified. In patients without metastatic disease, 3-year disease-free and overall survival rates were 70% and 86%, respectively, whereas in patients with metastases they were both 21%. Follow-up of surviving patients was 6-178 months (median, 41 months).

CONCLUSION

In this unfavorable cohort of ESFT patients, radiation therapy was an effective modality for local control, especially for patients without metastases. The presence of metastases at diagnosis is a predictive factor not only for death but also for local failure.

Treatment of osteosarcoma at first recurrence after contemporary therapy: the Memorial Sloan-Kettering Cancer Center experience

BACKGROUND

Overall survival after recurrence of osteosarcoma (OS) is < 30%. The authors reported their experience treating recurrent OS at the time of first recurrence (R1).

METHODS

Patients with high-grade OS who achieved complete disease remission (CR) after primary surgery and chemotherapy, and patients who were treated at R1 at Memorial Sloan-Kettering Cancer Center (New York, NY) after 1990 were analyzed by retrospective chart review.

RESULTS

For 43 eligible patients, the median time to R1 from initial diagnosis was 21.7 months (range, 4.6-135.7 mos). The lungs were the most common sites of disease recurrence (n = 33 of 43). With a median follow-up of 15.2 months (range, 0.7-158.3 mos) after R1, 15 of 43 (35%) patients were alive. Four of 43 patients were treated with surgery alone (3 patients were alive and 1 had died of progressive disease at the time of last follow-up). Due to unresectable disease, eight patients received only chemotherapy, none of whom survived. For patients with disease recurrence treated with chemotherapy and surgery (n = 31), 22 patients achieved a second CR (CR2). Nine patients were alive and in disease remission (29%) at the time of last follow-up. Twenty-three patients received ifosfamide as part of their retrieval regimen. Of the 18 who achieved a CR2, 8 experienced disease recurrence, 7 remain alive in CR2, and 3 died due to toxicity. Eight patients did not receive ifosfamide. Of these, 4 achieved a CR2 but 3 subsequently experienced disease recurrence.

CONCLUSIONS

At R1, 22 of 31 patients achieved a CR2 with aggressive surgery and chemotherapy. The majority of these patients subsequently developed a disease recurrence. Patients appeared to benefit from the addition of ifosfamide to their retrieval regimens. In the end, the role of chemotherapy in recurrent OS continues to remain undefined.

Use of an absorbable membrane to position biologically inductive materials in the periprosthetic space of cemented joints

A device is presented that positions ultrahigh molecular weight polyethylene (UHMWPE) debris against periprosthetic bone surfaces. This can facilitate the study of aseptic loosening associated with cemented joint prostheses by speeding the appearance of this debris within the periprosthetic space. The device, composed of a 100 microm thick bioabsorbable membrane impregnated with 1.4 x 10(9) sub-micron particles of UHMWPE debris, is positioned on the endosteum of the bone prior to the insertion of the cemented orthopedic implant. An in vitro pullout study and an in vivo canine pilot study were performed to investigate its potential to accelerate "time to aseptic loosening" of cemented prosthetic joints. Pullout studies characterized the influence of the membrane on initial implant fixation. The tensile stresses (mean+/-std.dev.) required to withdraw a prosthesis cemented into canine femurs with and without the membrane were 1.15+/-0.3 and 1.54+/-0.01 MPa, respectively; these findings were not significantly different (p > 0.4). The in vivo pilot study, involving five dogs, was performed to evaluate the efficacy of the debris to accelerate loosening in a canine cemented hip arthroplasty. Aseptic loosening and lameness occurred within 12 months, quicker than the 30 months reported in a retrospective clinical review of canine hip arthroplasty.

Acetabular development after bipolar hemiarthroplasty for osteosarcoma in children

A retrospective analysis was performed of eight patients with an open triradiate cartilage, who underwent resection for osteosarcoma and reconstruction of the proximal femur with a hemiarthroplasty, in order to identify changes of acetabular development. An analysis of the centre-edge angle, teardrop-to-medial prosthesis distance, superior joint space, teardrop-to-superior prosthesis distance, degree of lateral translation, and arthritic changes, was performed on serial radiographs. The median age at the time of the initial surgery was 11 years (5 to 14).

All patients developed progressive superior and lateral migration of the prosthetic femoral head. Following hemiarthroplasty in the immature acetabulum, the normal deepening and enlargement of the acetabulum is arrested. The degree of superior and lateral migration of the prosthetic head depends on the age at diagnosis and the length of follow-up.

Cell proliferation of cultured human cancer cells are affected by the elevated tumor pressures that exist in vivo

Elevated interstitial fluid pressure (IFP) is observed in most solid tumors. However, the study of the cellular processes of tumors and the development of chemotherapy are routinely studied using in vitro culture systems at atmospheric pressure. Using a new pressurized cell culture system, we investigated the influence of hydrostatic pressure on population dynamics of three primary osteosarcoma (HOS, U2OS, SaOS2) and two metastatic tumor cell lines (MCF7 breast, H1299 lung) that invade bone. Values of IFP in normal human bone and muscle, and in osteosarcoma tumors obtained during their surgical biopsy established the hydrostatic pressure range for the in vitro cell studies. The IFP values were obtained from a retrospective review of patient records. IFP from confirmed osteosarcoma was 35.9+/- 16.2 mmHg. Tumor IFP was significantly higher than muscle IFP (p < 0.001) and bone IFP (p < 0.003). The in vitro study measured the cell-line proliferation using hydrostatic pressures of 0, 20, 50 and 100 mmHg. The findings suggest that hydrostatic pressure either increases or decreases tumor proliferation rates depending on cell type. Furthermore, cell death was not associated with apoptosis.

Survival in patients operated on for pathologic fracture: implications for end-of-life orthopedic care

PURPOSE

Life expectancy is routinely used as part of the decision-making process in deciding the value of surgery for the treatment of bone metastases. We sought to investigate the validity of frequently used indices in the prognostication of survival in patients with metastatic bone disease.

METHODS

The study prospectively assessed 191 patients who underwent surgery for metastatic bone disease. Diagnostic, staging, nutritional, and hematologic parameters cited to be related to life expectancy were evaluated. Preoperatively, the surgeon recorded an estimate of projected life expectancy for each patient. The time until death was recorded.

RESULTS

Kaplan-Meier survival analyses indicated that the survival estimate, primary diagnosis, use of systemic therapy, Eastern Cooperative Oncology Group (ECOG) performance status, number of bone metastases, presence of visceral metastases, and serum hemoglobin, albumin, and lymphocyte counts were significant for predicting survival (P < .004). Cox regression analysis indicated that the independently significant predictors of survival were diagnosis (P < .006), ECOG performance status (P < .04), number of bone metastases (P < .008), presence of visceral metastases (P < .03), hemoglobin count (P < .009), and survival estimate (P < .00005). Diagnosis, ECOG performance status, and visceral metastases covaried with surgeon survival estimate. Linear regression and receiver-operator characteristic assessment confirmed that clinician estimation was the most accurate predictor of survival, followed by hemoglobin count, number of visceral metastases, ECOG performance status, primary diagnosis, and number of bone metastases. Nevertheless, survival estimate was accurate in predicting actual survival in only 33 (18%) of 181 patients.

CONCLUSION

A better means of prognostication is needed. In this article, we present a sliding scale for this purpose.