time dependency of prognostic factors in patients with stage II osteosarcomas

Subclonal Somatic Copy-Number Alterations Emerge and Dominate in Recurrent Osteosarcoma

Multiple large-scale genomic profiling efforts have been undertaken in osteosarcoma to define the genomic drivers of tumorigenesis, therapeutic response, and disease recurrence. The spatial and temporal intratumor heterogeneity could also play a role in promoting tumor growth and treatment resistance. We conducted longitudinal whole-genome sequencing of 37 tumor samples from 8 patients with relapsed or refractory osteosarcoma. Each patient had at least one sample from a primary site and a metastatic or relapse site. Subclonal copy-number alterations were identified in all patients except one. In 5 patients, subclones from the primary tumor emerged and dominated at subsequent relapses. MYC gain/amplification was enriched in the treatment-resistant clones in 6 of 7 patients with multiple clones. Amplifications in other potential driver genes, such as CCNE1, RAD21, VEGFA, and IGF1R, were also observed in the resistant copy-number clones. A chromosomal duplication timing analysis revealed that complex genomic rearrangements typically occurred prior to diagnosis, supporting a macroevolutionary model of evolution, where a large number of genomic aberrations are acquired over a short period of time followed by clonal selection, as opposed to ongoing evolution. A mutational signature analysis of recurrent tumors revealed that homologous repair deficiency (HRD)-related SBS3 increases at each time point in patients with recurrent disease, suggesting that HRD continues to be an active mutagenic process after diagnosis. Overall, by examining the clonal relationships between temporally and spatially separated samples from patients with relapsed/refractory osteosarcoma, this study sheds light on the intratumor heterogeneity and potential drivers of treatment resistance in this disease.

SIGNIFICANCE

The chemoresistant population in recurrent osteosarcoma is subclonal at diagnosis, emerges at the time of primary resection due to selective pressure from neoadjuvant chemotherapy, and is characterized by unique oncogenic amplifications.

Surgical Treatment of Osteosarcoma Induced Distant Pre-Metastatic Niche in Lung to Facilitate the Colonization of Circulating Tumor Cells

Recently, the major challenge in treating osteosarcoma patients is the metastatic disease, most commonly in the lungs. However, the underlying mechanism of recurrence and metastasis of osteosarcoma after surgical resection of primary tumor remains unclear. This study aims to investigate whether the pulmonary metastases characteristic of osteosarcoma is associated with surgical treatment and whether surgery contributes to the formation of pre-metastatic niche in the distant lung tissue. In the current study, the authors observe the presence of circulating tumor cells in patients undergoing surgical resection of osteosarcoma which is correlated to tumor recurrence. The pulmonary infiltrations of neutrophils and Gr-1+ myeloid cells are characterized to form a pre-metastatic niche upon the exposure of circulating tumor cells after surgical resection. It is found that mitochondrial damage-associated molecular patterns released from surgical resection contribute to the formation of pre-metastatic niche in lung through IL-1β secretion. This study reveals that surgical management for osteosarcoma, irrespective of the primary tumor, might promote the formation of postoperative pre-metastatic niche in lung which is with important implications for developing rational therapies during peri-operative period.

Clinical Prognostic Factors and Outcome in Pediatric Osteosarcoma: Effect of Delay in Local Control and Degree of Necrosis in a Multidisciplinary Setting in Lebanon

PURPOSE

Outcomes in pediatric osteosarcoma have dramatically improved over the past few decades, with overall survival rates of 70% and 30% for patients with localized and metastatic disease, respectively.

PATIENTS AND METHODS

We retrospectively reviewed clinical characteristics and outcomes of 38 patients treated between 2001 and 2012 at a single institution in Lebanon. All patients received a uniform three-drug chemotherapy regimen consisting of cisplatin, doxorubicin, and methotrexate. Ifosfamide and etoposide were added to the adjuvant treatment regimen in case of metastatic disease and/or poor degree of tumor necrosis (< 90%).

RESULTS

After a median follow-up of 61 months (range, 8 to 142 months), patients with localized disease had 5-year overall and event-free survival rates of approximately 81% and 68%, respectively, whereas for metastatic disease, they were approximately 42%. The most common primary site was the long bones around the knee (n = 34; 89.5%). Six patients (15.8%) had metastatic disease to lungs, and three (7.9%) had synchronous multifocal bone disease with lung metastases. Adverse prognostic factors included nonlower extremity sites, metastasis, poor degree of necrosis, and delay of more than 4 weeks in local control. In bivariable analysis, only degree of necrosis was a prognostic predictor for survival and disease recurrence.

CONCLUSION

Treatment of pediatric osteosarcoma in a multidisciplinary cancer center in Lebanon resulted in survival similar to that in developed countries. Delay in local control was associated with worse outcome. The only statistically significant inferior outcome predictor was poor degree of necrosis at the time of local control.

Bone transport using the Ilizarov method for osteosarcoma patients with tumor resection and neoadjuvant chemotherapy

Background

Studies on the applications of bone transport using the Ilizarov method for osteosarcoma (OS) patients with surgical resection and neoadjuvant chemotherapy are rare.

Methods

A retrospective analysis was conducted in 10 patients with limb OS receiving limb-salvage treatment by Ilizarov method from 2007 to 2012 in our hospital. The general information, treatment outcomes and follow-up data of the patients were collected.

Results

The mean length of the transported fragment and the mean transport distance of the affected limb were both 14 cm. The mean time in the external fixator was 34.2 ± 11.2 months (16-47 months) and the mean external fixation index (EFI) was 75 days/cm. The mean follow-up time was 68.6 ± 26.6 months (37-103 months). Seven patients underwent additional operations to treat the postoperative complications, and the mean number of operation was 1.7 times. Only one patient underwent amputation due to tumor relapse and all patients survived without tumor. The limb-salvage rate was 90%. At the time of external fixator removal, the ASAMI-bone score was good in 66.7% of patients and the ASAMI-function score was fair in 66.7% of cases. The mean MSTS score was 18.6 ± 3.2 (n = 9). At 10 months after fixator removal, both the ASAMI-bone score and ASAMI-function score were both excellent in 80% and good in 20% cases, and the mean MSTS score was further improved to 27.2 ± 1.11 (n = 5).

Conclusion

Bone transport using the Ilizarov method can achieve good therapeutic effectiveness in the limb-salvage treatment for OS patients with neoadjuvant chemotherapy as long as the complications can be timely recognized and well managed.

Combinatorial screening using orthotopic patient derived xenograft-expanded early phase cultures of osteosarcoma identify novel therapeutic drug combinations

Lead discovery in osteosarcoma has been hampered by the lack of new agents, limited representative clinical samples and paucity of accurate preclinical models. We developed orthotopic patient-derived xenografts (PDXs) that recapitulated the molecular, cellular and histologic features of primary tumors, and screened PDX-expanded short-term cultures and commercial cell lines of osteosarcoma against focused drug libraries. Osteosarcoma cells were most sensitive to HDAC, proteasome, and combination PI3K/MEK and PI3K/mTOR inhibitors, and least sensitive to PARP, RAF, ERK and MEK inhibitors. Correspondingly, PI3K signaling pathway genes were up-regulated in metastatic tumors compared to primary tumors. In combinatorial screens, as a class, HDAC inhibitors showed additive effects when combined with standard-of-care agents gemcitabine and doxorubicin. This lead discovery strategy afforded a means to perform high-throughput drug screens of tumor cells that accurately recapitulated those from original human tumors, and identified classes of novel and repurposed drugs with activity against osteosarcoma.

Dexrazoxane Significantly Reduces Anthracycline-induced Cardiotoxicity in Pediatric Solid Tumor Patients: A Systematic Review

Cardiotoxicity is a dose-limiting and potentially lethal complication of anthracycline administration. Previous studies failed to determine definitive toxic doses or cardioprotective factors. Current dosing strategies may utilize unnecessarily high anthracycline doses, such that survival benefit may not outweigh increased toxicity rates. A systematic review of randomized controlled trials and prospective/retrospective studies investigating anthracycline treatment in pediatric solid tumors was performed from PubMed/MEDLINE and Cochrane databases. Generalized linear models mapping survival, cardiotoxicity, and cardiotoxicity-free survival adjusted for male-to-female ratio, follow-up time, and concomitant chemotherapeutic drugs or cardioprotective agents (dexrazoxane) were generated using R. Survival rose linearly with increasing cumulative anthracycline dose whereas cardiotoxicity demonstrated exponential increases both without (dose, >200 mg/m) and with (dose, >400 mg/m) dexrazoxane. Maximum cardiotoxicity-free survival was 268.2 mg/m without and 431.8 mg/m with dexrazoxane. Despite increasing cardiotoxicity-free dose by >150 mg/m, dexrazoxane minimally improved projected survival (71.9% vs. 75.4%). Cardiotoxicity increased linearly as a function of follow-up time with rates doubling from 5 to 20 years, without evidence of plateau. On the basis of our model, current dosing regimens-doxorubicin doses >375 mg/m without dexrazoxane-overvalue increased anthracycline administration and may contribute to devastating cardiotoxicity. The linear increase of cardiotoxicity without evidence of plateau confirms the necessity for lifelong cardiac monitoring.

Relationship of peak serum methotrexate concentration to prognosis and drug tolerance in non-metastatic extremity osteosarcomas

PURPOSE

This study aimed to explore whether peak serum methotrexate concentration (C_max) correlated with adverse events, overall survival (OS) and event-free survival (EFS) in patients with primary extremity osteosarcoma.

METHODS

Patients with extremity osteosarcoma who were treated at our center between 2005 and 2015 were retrospectively studied. All the patients were Enneking stage II and had received standard perioperative chemotherapy composed of high-dose methotrexate, doxorubicin, cisplatin and ifosfamide. C_max and treatment-associated toxicities of each cycle were recorded. OS and EFS were estimated and compared by Kaplan-Meier survival analysis, and Cox regression models were performed for univariate comparisons.

RESULTS

In total, 567 patients were followed for an average of 53 months (24-104 months). The estimated 3- and 5-year EFS were 71.7 and 63.1%, and the 3- and 5-year OS were 78.2 and 72.9%, respectively. C_max ranged from 527 to 2495 µmol/L with a mean value of 931 ± 106 µmol/L. No significant differences in EFS and OS (p = 0.18 and p = 0.28) were observed among patients with a mean C_max > 1500, > 1000, > 700 and < 700 µmol/L. However, patients with a mean C_max > 1500 µmol/L had significantly increased rates of grade 3-5 toxicity. In the univariate analysis, C_max was not a prognostic factor for EFS (p = 0.08) or OS (p = 0.16).

CONCLUSIONS

C_max did not correlate significantly with the oncologic prognosis of non-metastatic extremity osteosarcoma patients treated by multi-agent chemotherapy; however, C_max correlated closely with toxicities and complications. The persistent inclusion of methotrexate in classical multidisciplinary chemotherapy was questioned and should be examined in future trials.

Ambulatory High-dose Methotrexate Administration in Pediatric Osteosarcoma Patients at a Single Institution in Argentina

BACKGROUND

The purpose of this study was to evaluate the feasibility and safety of ambulatory high-dose methotrexate (HDMTX) administration with oral hydration, alkalinization, and leucovorin rescue. HDMTX (12 g/m) was given intravenously over 4 hours after urine alkalinization. Families and patients were instructed to continue ambulatory oral hydration and alkalinization to monitor urine pH and to adjust bicarbonate according to our institution's treatment algorithm. Clinical status and MTX levels were controlled every 24 hours, and oral leucovorin dose was adjusted accordingly.

RESULTS

From April 2007 to December 2010, 150 of 447 courses of HDMTX (31.4%) were given on an outpatient basis, and 91.2% were successfully completed. The main causes of failure were poor oral tolerance (n=6) and fever (n=4). Most patients (81%) had MTX levels of <10 μmol/L 24 hours post-HDMTX; only in 1 course the levels were >50 μmol/L (50.96 μmol/L). Neutropenia grade III/IV was observed in 18.3% of the courses, grade III/IV leukopenia in 2.7%, and grade III/IV thrombocytopenia and anemia in 4.7%. Around 39% were associated with grade III/IV hepatic toxicity (asymptomatic hypertransaminasemia), grade III-IV gastrointestinal toxicity (vomiting and diarrhea) (5%), grade III-IV mucositis (4%), and none of the patients developed renal toxicity.

CONCLUSIONS

Ambulatory HDMTX administration is feasible and safe in a population with poor resources in a developing country.

Pediatric Sarcomas

Pediatric sarcomas are a heterogeneous group of tumors accounting for approximately 10% of childhood solid tumors. Treatment is focused on multimodality therapy, which has improved the prognosis over the past two decades. Current regimens focus on decreasing treatment for low-risk patients to decrease the long-term side effects while maximizing therapy for patients with metastatic disease to improve survival. Pediatric sarcomas can be divided into soft tissue sarcomas and osseous tumors. Soft tissue sarcomas are further delineated into rhabdomyosarcomas, which affect young children and nonrhabdomyosarcomas, which are most common in adolescents. The most common bone sarcomas are osteosarcomas and Ewing's sarcoma.

Bone mineral density change during adjuvant chemotherapy in pediatric osteosarcoma

PURPOSE

Osteoporosis is currently receiving particular attention as a sequela in survivors of childhood osteosarcoma. The aim of this study was to evaluate bone mineral density (BMD) changes during methotrexate-based chemotherapy in children and adolescents with osteosarcoma.

METHODS

Nine patients with osteosarcoma were included in this retrospective study and compared with eight healthy controls. BMD of the lumbar spine and unaffected femur neck of patients was serially measured by dual-energy x-ray absorptiometry (DXA) before and just after chemotherapy and compared with controls.

RESULTS

Four patients (44%) showed decreased lumbar spine BMD and seven patients (78%) showed decreased femur neck BMD, while all controls showed increased lumbar and femur BMD (P=0.024 and P=0.023). The femur neck BMD z-scores decreased from -0.49±1.14 to -1.63±1.50 (P=0.032). At the end of therapy, five patients (56%) showed femur neck BMD z-scores below -2.0.

CONCLUSION

The bone metabolism is disturbed during therapy in children with osteosarcoma, resulting in a reduced BMD with respect to healthy controls. Since a reduced BMD predisposes to osteoporosis, specific attention and therapeutic interventions should be considered.

Development and external validation of nomograms predicting distant metastases and overall survival after neoadjuvant chemotherapy and surgery for patients with nonmetastatic osteosarcoma: A multi-institutional study

BACKGROUND

In this era of individualized cancer treatment, data that could be applied to predicting the survival of patients with osteosarcoma are still limited because of the rarity of the disease and the difficulty in accumulating a sufficient number of patients. Therefore, a multi‐institutional collaboration was implemented to develop and externally validate nomograms that would predict metastasis‐free survival (MFS) and overall survival (OAS) for patients with nonmetastatic osteosarcoma.

METHODS

This study retrospectively examined 1070 patients treated with neoadjuvant chemotherapy and surgery for nonmetastatic osteosarcoma. Data from Japanese patients (n = 557) were used to develop multivariate nomograms based on Cox regression. Six clinical and pathologic variables were built into nomograms estimating the probability of MFS and OAS 3 and 5 years after diagnosis. The model was internally validated for discrimination and calibration with bootstrap resampling and was externally validated with an independent patient cohort from Korea (n = 513).

RESULTS

A patient's age, tumor site, and histologic response were found to have a stronger influence on MFS and OAS in the model than sex, tumor size, or pathologic fracture. The nomograms and calibration plots based on these results well predicted the probability of MFS (concordance index, 0.631) and OAS (concordance index, 0.679). The concordance indices for external validation were 0.682 for MFS and 0.665 for OAS.

CONCLUSIONS

The nomograms were externally validated and verified to be useful for the prediction of MFS and OAS and for the assessment of the postoperative prognosis. They can be used for counseling patients and for establishing appropriate surveillance strategies after surgery. Cancer 2015;121:3844–3852. © 2015 American Cancer Society.

Prognostic nomograms for osteosarcoma have been developed and externally validated through multi‐institutional collaboration. These prognostic nomograms are the first to be developed and externally validated for osteosarcoma.

Temporary hemiarthroplasty with a synthetic device in children with osteosarcoma around the knee as a bridging procedure until skeletal maturity

BACKGROUND

We hypothesized that hemiarthroplasty with a synthetic device in skeletally immature patients with osteosarcoma around the knee would be functional due to high adaptability in the pediatric age group, and may decrease the number of surgeries until limb equalization by preserving the nearby physis.

METHODS

We analyzed the outcomes of 25 hemiarthroplasties (12 distal femur, 13 proximal tibia). Average patient age was 11.8 years. We assessed (1) whether hemiarthroplasty could be considered as a viable option and could preserve growth of the nearby physis, and (2) whether these patients could reach the final goal of adult-type tumor prosthesis implantation within a preplanned number of surgeries.

RESULTS

Three (12%) of 25 hemiarthroplasties showed failure. Average Musculoskeletal Tumor Society functional score of 23 patients was 25.1. Average tibial and femoral shortening for the corresponding reconstruction was 0.3 cm and 0.5 cm, respectively. In terms of number of surgeries for limb equalization, 19 patients (76%) had less, four (16%) had equal, and two (8%) had more surgeries than planned.

CONCLUSIONS

Hemiarthroplasty is a sound option until skeletal maturity, allowing surgeons to choose the appropriate procedure based on the patient's growth status, and may reduce the amount of shortening by preserving nearby physis.

Usefulness of increased 18F-FDG uptake for detecting local recurrence in patients with extremity osteosarcoma treated with surgical resection and endoprosthetic replacement

OBJECTIVE

To investigate the changes of increased F-18 fluorodeoxyglucose ((18)F-FDG) uptake around the prosthesis and its ability to differentiate local recurrence from postsurgical change after endoprosthetic replacement in extremity osteosarcoma.

MATERIALS AND METHODS

A total of 355 positron emission tomography (PET)/computed tomography (CT) scans in 109 extremity osteosarcoma patients were retrospectively analyzed. All patients were followed up with (18)F-FDG PET/CT for more than 3 years after tumor resection. For semiquantitative assessment, we drew a volume of interest around the entire prosthesis of the extremity and measured the maximum standardized uptake value (SUV max). Independent samples t test was used to compare SUV max at each follow-up time. SUV max at 3 months (SUV1) and SUV max at the time of local recurrence in patients with recurrence or at the last follow-up in others (SUV2) were compared using the Mann-Whitney test. Diagnostic performances of PET parameters were assessed using ROC curve analyses.

RESULTS

Nine patients (8 %) showed a local recurrence. Mean SUV max at 3, 12, 24, and 36 months was 3.1 ± 1.5, 3.8 ± 1.9, 3.6 ± 1.9, and 3.7 ± 1.5 respectively. In ROC curve analysis, the combination of SUV2 >4.6 and ΔSUV >75.0 was a more useful parameter for predicting local recurrence than SUV2 or ΔSUV alone. The sensitivity, specificity, and accuracy for identifying local recurrence were 89, 76, 77 % for SUV2; 78, 81, 81 % for ΔSUV; and 78, 94, 93 % for the combined criterion respectively.

CONCLUSION

The combination of SUV2 and ΔSUV was more useful than the SUV2 or ΔSUV used alone for the prediction of local recurrence.

Spontaneous necrosis and additional tumor necrosis induced by preoperative chemotherapy for osteosarcoma: a case-control study

BACKGROUND

Extent of spontaneous necrosis in untreated osteosarcoma may imply tumor aggressiveness. Reports regarding this issue are scarce and there are several points to be clarified; (1) the correlation between tumor size and extent of spontaneous necrosis displayed was conflicting, (2) whether there is difference in necrosis rate between intra- and extra-medullary portion of tumor is not described, if it does, its relation with other clinico-pathologic variables, (3) in patients with surgical treatment only, >20 % spontaneous necrosis was a poor prognostic factor, however, whether that cutoff is still valid in chemotherapy cohort remains to be determined, (4) expected additional tumor necrosis by chemotherapy was made by simply comparing the necrosis rates of untreated and treated osteosarcoma cohort.

METHODS

We evaluated spontaneous necrosis in 43 osteosarcoma patients (39 Stage IIB, 4 Stage III). We evaluated overall necrosis rate and separately evaluated the necrosis rate of intra- and extra-medullary portion of tumor. These results were compared with other clinico-pathologic variables. To evaluate additional tumor necrosis induced by neoadjuvant chemotherapy, case (38 without preoperative chemotherapy)-control (76 with preoperative chemotherapy) study was performed.

RESULTS

The mean spontaneous necrosis rate was 23 %. Overall spontaneous necrosis was not associated with tumor volume. Necrosis rate of extramedullary tumors was higher in cases of large tumors (p = 0.02). In patients with upfront surgery followed by chemotherapy, 5-year event-free survival rate of patients with >20 and <20 % spontaneous necrosis were 82 ± 17 and 79 ± 18.5 %, respectively (p = 0.75). After chemotherapy, regardless of tumor volume and location, control group tumors showed an increase in the tumor necrosis of approximately 50 %.

CONCLUSION

In chemotherapy era, the extent of spontaneous necrosis has no relation with survival. The expected additional tumor-killing effect of preoperative chemotherapy is around 50 % of initial tumor volume.

Postoperative nomogram to predict the probability of metastasis in Enneking stage IIB extremity osteosarcoma

BACKGROUND

Metastasis is the most crucial prognostic factor in osteosarcoma. The goal of this study was to develop a new nomogram to predict the probability of metastasis in Enneking stage IIB extremity osteosarcoma after neoadjuvant chemotherapy and limb salvage surgery.

METHODS

We examined medical records of 91 patients who had undergone surgery between March 1994 and March 2007. A nomogram was developed using multivariate logistic regression. The nomogram was validated internally by bootstrapping-method (200 repetitions) and externally in independent validation set (n = 34). A Youden-derived cutoff value was assigned to the nomogram to predict dichotomous outcomes for metastasis.

RESULTS

The nomogram was built from four predictors of tumor site, serum alkaline phosphatase, intracapsular extension, and Huvos grade, and an additional clause that the cutoff value should be added to the total points in the cases of incomplete surgical resection. P-value of Hosmer and Lemshow Goodness-of-fit test of this model was 0.649. Area under receiver operating curve values of 0.83 (95% confidence interval [CI], 0.75 to 0.92) in the training set and 0.80 (95% CI, 0.63 to 0.96) in the validation set were obtained. The accuracy of dichotomous outcomes was 79.1% (95% CI, 0.69 to 0.86) and 82.4% (95% CI, 0.63 to 0.92) in the training and validation sets.

CONCLUSIONS

We have developed a new high-performance nomogram to predict the probability of metastasis in Enneking stage IIB extremity osteosarcoma after limb salvage surgery.

Proximal tumor location and fluid-fluid levels on MRI predict resistance to chemotherapy in stage IIB osteosarcoma

BACKGROUND

Primary tumor growth during neoadjuvant chemotherapy is believed to be a sign of resistance to chemotherapy (chemoresistance), and often is associated with poor histologic response, local recurrence, and poorer survival. Currently there are no proven indicators to predict poor response to chemotherapy at the time of diagnosis.

QUESTIONS/PURPOSES

We asked (1) what clinicopathologic factors present at diagnosis predict primary tumor growth during neoadjuvant chemotherapy, (2) what factors at presentation predict survival, and (3) when the factors at presentation and the treatment-related factors are considered, what factors independently correlate with survival.

METHODS

We studied 567 patients with Stage IIB osteosarcomas. The factors assessed included age, sex, location, pattern on plain radiographs (radiodense, radiolucent, mixed), MRI findings, pathologic subtype, initial tumor volume determined by MRI, tumor volume change after chemotherapy, surgical margin, and histologic response to preoperative chemotherapy. Logistic modeling was used to identify risk factors.

RESULTS

Independent risk factors associated with primary tumor growth after neoadjuvant chemotherapy were proximal tumor location (p < 0.01; relative risk [RR], 2.41; 95% CI, 1.5-3.86) and fluid-fluid level on initial MRI (p < 0.01; RR, 5.56; 95% CI, 3.48-8.87). Among factors at presentation, large initial tumor volume (p < 0.01; RR, 1.58; 95% CI, 1.22-2.04), proximal tumor site (p < 0.01; RR, 1.61; 95% CI, 1.19-2.19), and presence of fluid-fluid level (p < 0.01; RR, 1.83; 95% CI, 1.37-2.5) independently predicted reduced event-free survival. When we consider the factors at presentation and treatment-related factors, large initial tumor volume (p < 0.01; RR, 1.54), tumor growth after neoadjuvant chemotherapy (p < 0.01; RR, 3.88), inadequate surgical margin (p < 0.01; RR, 2.42), and poor histologic response (p = 0.03; RR, 1.43) were independent poor prognostic factors of event-free survival.

CONCLUSIONS

Proximal tumor location and the presence of the fluid-fluid level on initial MRI were predictors of tumor progression and poor survival in patients presenting with Stage IIB osteosarcomas. If confirmed in other studies, patients with these risk factors should be considered for trials of other treatment strategy.

LEVEL OF EVIDENCE

Level III, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.

Plain radiologic findings and chronological changes of incipient phase osteosarcoma overlooked by primary physicians

Background

We assessed the plain radiographic characteristics of 10 cases of osteosarcomas during the initial painful period that had been overlooked by a primary physician. In addition, we evaluated chronologic changes in radiographic findings from initial symptomatic period to the time of accurate diagnosis.

Methods

The clinical records were reviewed for clinical parameters including age, sex, location, presenting symptoms, initial diagnosis, duration from initial symptoms to definite diagnosis, and initial and follow-up plain radiographic findings of the lesion.

Results

Initial clinical diagnoses included a sprain in 6, growing pain in 2, stress fracture in 1, and infection in 1 patient. Initial plain radiographic findings were trabecular destruction (100%), cortical disruption (60%), periosteal reaction (60%), and soft tissue mass (10%). Intramedullary matrix changes were osteosclerosis in 6 and osteolysis in 4 patients. On progression, 4 cases with minimal sclerosis changed to osteoblastic lesion in 3 patients and osteolytic lesion in 1. Four cases with faint osteolytic foci transformed into osteolytic lesion in 3 and mixed pattern in 1.

Conclusions

Notable plain radiologic findings of incipient-stage osteosarcoma include trabecular disruption along with faint osteosclerosis or osteolysis. In symptomatic patients with trabecular destruction, additional imaging study including magnetic resonance imaging should be performed to exclude osteosarcoma in the incipient phase, even without radiologic findings suggesting malignant tumor, such as cortical destruction or periosteal reaction.

Correlation between fluid-fluid levels on initial MRI and the response to chemotherapy in stage IIb osteosarcoma

BACKGROUND

The presence of fluid-fluid levels (FFLs) on osteosarcoma magnetic resonance imaging (MRI) is underestimated as a nonspecific finding; however, we hypothesized that FFL in conventional osteosarcoma may be indicative of chemoresistance.

METHODS

In 567 stage IIB osteosarcoma patients, we evaluated the following: the incidence of FFL and their correlation with other clinicopathological variables; tumor volume change after chemotherapy and survival according to the presence of FFL; and the relationship between survival and the extent of FFL.

RESULTS

One hundred eight (19 %) tumors showed FFL on initial MRI. FFL were correlated with proximal humeral location (P = 0.017), osteolytic on plain radiographs (P < 0.001), tumor enlargement after chemotherapy (P < 0.001), and poor histological response (P = 0.005). Large tumor (P < 0.01), proximal tumor location (P = 0.01), and presence of FFL (P < 0.01) were independent predictors of poor survival. Compared to the extensive FFL (more than one third of the tumor), small foci of FFL (less than one third of the tumor) showed a high tendency for tumor enlargement after chemotherapy (P < 0.001), poor histologic response (P = 0.001), and worse survival (P < 0.001).

CONCLUSIONS

FFL on initial MRI could predict tumor progression after chemotherapy. Notably, tumors with small foci of FFL (less than one third of the tumor) have a high propensity for poor outcome. Patients with this finding should be considered for risk-adapted therapy.

Single institution retrospective review of perioperative chemotherapy in adult and adolescent patients with operable osteosarcoma

AIMS

Perioperative chemotherapy has improved the prognosis for patients with operable osteosarcoma. The literature is conflicting about which regimen is optimal. The aim of this study was to evaluate the survival outcomes of two cohorts of patients with operable osteosarcoma treated with different perioperative chemotherapy regimens.

METHODS

This was a retrospective review of patients diagnosed with operable osteosarcoma treated at the Princess Alexandra Hospital from 1986 to 2009. The standard perioperative chemotherapy regimen changed from the modified T10 Rosen protocol to cisplatin/doxorubicin in 1997. Using the Kaplan-Meier method, overall survival (OS) and disease-free survival (DFS) curves were generated for the cisplatin/doxorubicin and the modified T10 Rosen cohorts.

RESULTS

Seventy-one patients were identified of whom 63 had potentially curable disease. Of these, 24 received the modified T10 Rosen regimen and 39 received cisplatin/doxorubicin. There was a non-significant trend toward better OS and DFS in the patients who received the modified T10 Rosen protocol.

CONCLUSION

The trend toward poorer survival in the cisplatin/doxorubicin cohort, in combination with current evidence, has prompted our institution to change its practice.

Role of surgical margin on local recurrence in high risk extremity osteosarcoma: a case-controlled study

BACKGROUND

The relationship between surgical margin and local recurrence (LR) in osteosarcoma patients with poor responses to chemotherapy is unclear. Moreover, the incidences of LR according to three different resection planes (bone, soft tissue, and perineurovascular) are not commonly known.

METHODS

We evaluated the incidence of LR in three areas. To assess whether there is a role of surgical margin on LR in patients resistant to preoperative chemotherapy, we designed a case (35 patients with LR) and control (70 patients without LR) study. Controls were matched for age, location, initial tumor volume, and tumor volume change during preoperative chemotherapy.

RESULTS

LR occurred at the soft tissues in 18 cases (51.4%), at the perineurovascular tissues in 11 cases (31.4%), and at the bones in six cases (17.2%). The proportion of inadequate perineurovascular margin was higher in the case group than in the control group (p = 0.01). Within case-control group (105 patients), a correlation between each margin status and LR at corresponding area was found in the bone (p < 0.001) and perineurovascular area (p = 0.001).

CONCLUSIONS

LR is most common in soft tissues. In patients showing similar unfavorable responses to chemotherapy, the losses of perineurovascular fat plane on preoperative magnetic resonance imaging may be a valuable finding in predicting LR.

Initial metabolic tumor volume measured by 18F-FDG PET/CT can predict the outcome of osteosarcoma of the extremities

We evaluated the ability of metabolic and volumetric parameters measured by pretreatment (18)F-FDG PET/CT to predict the survival of patients with osteosarcoma of the extremities.

METHODS

The records of 83 patients with American Joint Committee on Cancer stage II extremity osteosarcoma treated with surgery and chemotherapy were retrospectively reviewed. Imaging parameters (maximum standardized uptake value, metabolic tumor volume [MTV], total lesion glycolysis, and tumor volume based on MR images) were measured before treatment, and histologic responses to neoadjuvant chemotherapy were assessed by examination of postsurgical specimens. Receiver-operating-characteristic curve analyses and the Cox proportional hazards model were used to analyze whether imaging and clinicopathologic parameters could predict metastasis-free survival.

RESULTS

Of the imaging parameters, MTV at the fixed standardized uptake value threshold of 2.0 (MTV(2.0)) most accurately predicted metastasis by receiver-operating-characteristic curve analysis (area under the curve = 0.679, P = 0.011). By multivariate analysis, MTV(2.0) > 105 mL (relative risk, 3.93; 95% confidence interval, 1.55-9.92) and poor response to neoadjuvant chemotherapy (relative risk, 4.83; 95% confidence interval, 1.64-14.21) independently shortened metastasis-free survival (P = 0.004 for both parameters). The stratification of patients by the combined criteria of MTV(2.0) and histologic response predicted outcome in more detail.

CONCLUSION

MTV is an independent predictor of metastasis in patients with osteosarcoma of the extremities. The combination of MTV and histologic response predicts survival more accurately than the chemotherapeutic response alone.

Osteosarcoma: evolution of treatment paradigms

This paper reviews the contribution of chemotherapy in the conquest of osteosarcoma. It discusses how the treatment of osteosarcoma has evolved over the last five decades, resulting in a more than fivefold increase in survival. Though the initial improvements in survival were dramatic, essentially there has been no change in the outlook for this disease over the past 30 years. The paper also highlights the necessity of a multidisciplinary approach to combat this disease and stresses the need to explore newer treatment agents in order to build on the lessons learnt from the past while striving to achieve greater levels of success.

Local recurrence has only a small effect on survival in high-risk extremity osteosarcoma

BACKGROUND

Tumor enlargement after chemotherapy is considered one of the high-risk factors for local recurrence and survival in osteosarcoma. We hypothesized patients with this risk factor will have similar survival regardless of the development of local recurrence.

QUESTIONS/PURPOSES

We asked (1) the prognostic factors for survival in our cohort, (2) how much effect local recurrence has on survival among patients with similar preoperative risk factors, and (3) what prognostic factors are important for survival in these selected patients.

METHODS

We analyzed the prognostic factors for survival in 449 patients with extremity osteosarcoma without metastatic disease at initial diagnosis and treatment (38 with local recurrence, 411 without local recurrence). We compared the survival difference between patients with local recurrence (n = 38) and without local recurrence (control, n = 76) matched for age, location, initial tumor volume, and tumor volume change after chemotherapy, and assessed prognostic factors in this subgroup.

RESULTS

In a cohort study, multivariate analysis revealed initial tumor volume, tumor enlargement, inadequate margin, and local recurrence predicted poor survival. In the case-control study, the 10-year metastasis-free survival rates of two groups were 13.1 ± 10.7% and 19.3 ± 9%, respectively. In the case-controlled groups, tumor enlargement and initial tumor volume showed multivariate significance.

CONCLUSIONS

Local recurrence has a small impact on survival in patients with high-risk osteosarcoma.

LEVEL OF EVIDENCE

Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

How can survival be improved in localized osteosarcoma?

Despite numerous chemotherapy trials and the introduction of novel agents, survival in localized osteosarcoma, which plateaued in the mid-1980s, has been recalcitrant to our best efforts. The authors considered that a review of previous and current strategies that target survival might provide a direction for research efforts. Here, the focus is placed mainly on the reappraisal of previous mass chemotherapy trials and prognostic factors, in the hope of contriving a strategy to overcome the current stasis.

Ambulatory high-dose methotrexate administration among pediatric osteosarcoma patients in an urban, underserved setting is feasible, safe, and cost-effective

BACKGROUND

We describe the safety, feasibility, and provide a cost-estimate of outpatient high-dose methotrexate administration (HDMTX) among an urban, underserved population.

PROCEDURE

A retrospective analysis of ambulatory HDMTX administration among osteosarcoma patients, at Montefiore Medical Center's Children's Hospital (Bronx, NY) was performed. HDMTX (12 g/m(2)) was given intravenously (IV) over 4 hr after urine alkalinization. Patients were discharged home to continue IV hydration and alkalinization delivered via a home infusion pump. Families were instructed to monitor urine pH overnight and management was adjusted according to our institution's treatment algorithm until MTX level ≤ 0.1 µmol/L. A cost estimate was performed to assess the difference in costs for outpatient versus hypothetical inpatient administrations.

RESULTS

Of the 97 ambulatory HDMTX administrations, 99% were successfully completed. One patient failed outpatient administration secondary to home infusion pump malfunction. This patient successfully completed subsequent courses as an outpatient. Most patients (72%) had a MTX level of < 10 µmol/L at 24 hr post-HDMTX. No patients were found to have a MTX level of > 50 µmol/L at 24 hr. About 26% of courses were associated with grade III or IV neutropenia, 4% were associated with grade III or IV thrombocytopenia and 1% were associated with grade III/IV leukopenia. Compared to a hypothetical hospital inpatient stay, the hospital costs for ambulatory HDMTX were an average of $1400 less per cycle.

CONCLUSION

Ambulatory HDMTX administration among an underserved, urban population is safe, feasible, and cost-effective.

Noninvasive imaging with thallium-201 scintigraphy may not correlate with survival in patients with osteosarcoma

BACKGROUND

Histologic response to preoperative chemotherapy is a strong prognostic factor for osteosarcoma (OS). Thallium-201 (Tl-201) scintigraphic response to initial chemotherapy has previously been described as a predictor of histologic response. In the current study, the authors re-examined a series of patients studied using Tl-201 scintigraphy to determine the correlation between changes observed on Tl-201 scintigraphy and event-free survival (EFS).

METHODS

A total of 22 patients with biopsy-proven OS of the extremity underwent Tl-201 imaging before and immediately after preoperative chemotherapy. The maximum pixel counts taken over the tumor divided by those taken of a background region yielded a tumor-to-background ratio (TBR). The percentage of change in the TBR before and after adjuvant chemotherapy, defined as the alteration ratio (AR), was correlated with EFS.

RESULTS

The median AR was 85% (range, 28-100%). The 3-year EFS was 0.72 (95% confidence interval [95% CI], 0.48-0.86) and the 5-year EFS was 0.67 (95% CI, 0.43-0.86). There was no association between AR and EFS detected in this cohort (hazard ratio, 0.99; 95% CI, 0.95-1.02 [Somers rank correlation coefficient, 0.15]).

CONCLUSIONS

Although Tl-201 scintigraphy was used as a tool for the assessment of response to chemotherapy in patients with OS, the AR did not appear to be predictive of EFS in this small group of patients. It is necessary to use the outcome variables of ultimate interest-EFS and overall survival- and not rely on surrogates for outcome to evaluate potential prognostic factors.

Safety concern between autologous fat graft, mesenchymal stem cell and osteosarcoma recurrence

BACKGROUND

Osteosarcoma is the most common malignant primary bone tumour in young adult treated by neo adjuvant chemotherapy, surgical tumor removal and adjuvant multidrug chemotherapy. For correction of soft tissue defect consecutive to surgery and/or tumor treatment, autologous fat graft has been proposed in plastic and reconstructive surgery.

PRINCIPAL FINDINGS

We report here a case of a late local recurrence of osteosarcoma which occurred 13 years after the initial pathology and 18 months after a lipofilling procedure. Because such recurrence was highly unexpected, we investigated the possible relationship of tumor growth with fat injections and with mesenchymal stem/stromal cell like cells which are largely found in fatty tissue. Results obtained in osteosarcoma pre-clinical models show that fat grafts or progenitor cells promoted tumor growth.

SIGNIFICANCE

These observations and results raise the question of whether autologous fat grafting is a safe reconstructive procedure in a known post neoplasic context.

Staged lengthening arthroplasty for pediatric osteosarcoma around the knee

BACKGROUND

Orthopaedic oncologists often must address leg-length discrepancy after resection of tumors in growing patients with osteosarcoma. There are various alternatives to address this problem. We describe a three-stage procedure: (1) temporary arthrodesis, (2) lengthening by Ilizarov apparatus, and (3) tumor prosthesis.

QUESTIONS/PURPOSES

We asked (1) to what extent are affected limbs actually lengthened; (2) how many of the patients who undergo a lengthening procedure eventually achieve joint arthroplasty; and (3) can the three-stage procedure give patients a functioning joint with equalization of limb length?

PATIENTS AND METHODS

We reviewed 56 patients (younger than 14 years) with osteosarcoma who had staged lengthening arthroplasty between 1991 and 2004.

RESULTS

Thirty-five of the 56 patients (63%) underwent soft tissue lengthening, and of these 35, 28 (50% of the original group of 56) had implantation of a mobile joint. Three of the 28 prostheses were later removed owing to infection after arthroplasty. The overall average length gained was 7.8 cm (range, 4-14 cm), and 25 (71%) of the 35 patients had a mobile joint at final followup. The average Musculoskeletal Tumor Society functional score was 23.2 (range, 15-28) and limb-length discrepancy at final followup was 2.6 cm (range, 0-6.5 cm). Although most mobile joints had an acceptable ROM (average, 74.2 degrees ; range, 35 degrees -110 degrees ), extension lag was frequent.

CONCLUSIONS

Our approach is one option for skeletally immature patients, especially in situations where an expandable prosthesis is not available. However, this technique requires multiple stages and would be inappropriate for patients who cannot accept prolonged functional deficit owing to a limited lifespan or other reasons.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Prognostic and predictive biomarkers of canine osteosarcoma

Canine osteosarcoma (OS) is an aggressive tumour that accounts for approximately 90% of primary bone tumours in the dog. Although the standard treatments (including limb amputation/sparing, chemotherapy and palliative radiotherapy) have significantly increased survival rates, almost 90% of animals will eventually develop predominantly pulmonary metastases. Despite advances in various therapies, prognosis remains poor, with median survival times ranging from 3 months to 1 year and <20% of dogs survive for >2 years following diagnosis. Various clinical and epidemiological markers have facilitated decision-making with respect to therapy but no single molecular biomarker has been shown to enhance prediction of disease progression. The publication of the canine genome in 2005 raised the possibility of increasing understanding of the genetic mechanisms underpinning canine OS. This review explores the use of biomarkers within the multi-disciplinary management of dogs with OS, and highlights the few known, potential prognostic/predictive molecular markers including their potential value as 'bridging biomarkers' for human OS. Although high-throughput profiling of canine OS remains in its infancy, research within the next decade using leading-edge screening technologies has the potential to identify biomarkers that may enhance diagnostic and prognostic accuracy and result in more effective, individually tailored, treatment and management protocols for affected dogs.

Prognostic effect of inadvertent curettage without treatment delay in osteosarcoma

BACKGROUND

Unplanned primary surgery has been known to have a negative prognostic impact in osteosarcoma.

METHODS

We identified 20 osteosarcoma patients that had undergone inadvertent surgery followed by adequate treatment without delay, and compared the clinicopathologic characteristics of these 20 case patients with those of 365 patients who underwent incisional biopsy. For survival analysis, 40 control patients matched for tumor size at presentation, tumor location, age and gender were selected from these 365 patients.

RESULTS

Unusual initial clinicopathologic characteristics were frequently observed in the case patients, such as, an older age, a small tumor size, an unusual tumor location, and a lytic radiographic pattern. The 5-year overall survival rate in the case group was 89.4 +/- 7.1% and in the control group was 83.9 +/- 6.1%, and the 5-year event-free survival rate in the case group was 90.0 +/- 6.7% and in the control group was 76.8 +/- 6.8%. The log rank test revealed no survival difference between the case and control groups.

CONCLUSIONS

As is the case for soft tissue sarcoma, inadvertent extensive curettage with no ensuing treatment delay was found to have no detrimental effect on overall- or event-free survival in osteosarcoma. Further study using a larger sample size is needed to confirm our results.

Prognostic effects of doctor-associated diagnostic delays in osteosarcoma

INTRODUCTION

In this retrospective study, we evaluated to what extent diagnostic delays impact prognosis in osteosarcoma.

MATERIALS AND METHODS

The authors identified 26 osteosarcoma patients who had undergone inappropriate procedure-associated diagnostic delays of more than 45 days after surgery, calculated overall survival rates, and analyzed clinicopathologic characteristics.

RESULTS

Initial clinical impressions were of a benign bone tumor in 15 patients, fracture in 8, and infection in 3. After initial inappropriate procedures, primary surgeons failed to send a tissue sample to a pathologist for definite diagnosis in 12 cases, and pathologists made incorrect diagnoses in the other 14. The average doctor-associated diagnostic delay after inappropriate surgery for these 26 patients was 10.5 months. Following referral to our institute, 22 underwent both surgery and chemotherapy and the remaining 4 patients underwent chemotherapy only. Four of the 26 patients were alive at last follow-ups. Estimated 5- and 10-year overall survival rates were 26 and 10%, respectively.

CONCLUSIONS

The present study shows that doctor-associated diagnostic delay superimposed on an inappropriate primary procedure has a significant detrimental effect on overall survival in osteosarcoma. This study demonstrates that surgeons and pathologists should spare no effort to minimize diagnostic errors and delays.

Prognostic effect of pathologic fracture in localized osteosarcoma: a cohort/case controlled study at a single institute

BACKGROUND

The negative prognostic role of pathologic fracture in osteosarcoma is not determined, as previous case-control and retrospective cohort studies have produced contradictory results.

METHODS

We conducted both cohort (n = 384) and case-control (n = 111) studies on 37 pathologically fractured localized osteosarcoma of extremity.

RESULTS

In cohort study, patients with a fracture showed a tendency of poorer survival, but the difference did not reach the level of significance (5-year metastasis-free survival rates; 48% for cases vs. 61% for controls; P = 0.06). A case-control study on 37 fractured and 74 control recruited from 347 patients matched for tumor size and location showed no survival difference between the cases and controls (P = 0.12).

CONCLUSIONS

Reported negative prognostic effect of a pathologic fracture is likely to be due to confounding by tumor size and location. The present study suggests that the presence of a pathologic fracture has no prognostic relevance.

Growth patterns of osteosarcoma predict patient survival

INTRODUCTION

In this retrospective study, we assessed tumor growth patterns as visualized on MR images, and examined whether tumor growth patterns correlate with clinicopathologic variables. In addition, we also evaluated the relationship between patient outcome and tumor growth pattern in the whole study cohort and in subsets of AJCC IIA and IIB patients.

MATERIALS AND METHODS

We retrospectively reviewed 347 patients with Enneking stage IIB and AJCC stage II osteosarcoma that was treated with surgery and neoadjuvant chemotherapy at our institute. Patients were divided into three groups based on tumor growth pattern, namely, concentric, eccentric, and longitudinal groups. Fisher's exact test was performed to analyze correlations between tumor growth patterns and clinicopathological variables. Five-year metastasis-free survival and overall survival were evaluated using univariate and multivariate analyses.

RESULTS

In terms of tumor growth patterns, 225 patients (64.8%) had a concentric, 71 (20.5%) an eccentric and 51 (14.7%) a longitudinal tumor. Eccentric tumors were usually small and responded well to chemotherapy, whereas concentric tumors were large and responded poorly. The prognostic significances of tumor growth patterns were confirmed by univariate and multivariate analyses. Among AJCC stage IIA patients, no survival difference was found according to growth pattern, whereas in AJCC stage IIB patients, longitudinal tumors were associated with significantly better survival than concentric tumors.

CONCLUSIONS

Tumor growth pattern was found to be an independent prognostic factor in stage II osteosarcoma. Moreover, longitudinally growing tumors were associated with better survival in AJCC stage IIB patients. Our results suggest that tumor growth pattern could be used as an indicator of risk-adapted therapy when combined with other prognostic factors.

Effect of increases in tumor volume after neoadjuvant chemotherapy on the outcome of stage II osteosarcoma regardless of histological response

BACKGROUND

We assessed volume changes after neoadjuvant chemotherapy and evaluated relations between tumor size changes and clinical characteristics. In addition, we sought to determine whether tumor size change influences patient outcome.

METHODS

The records of 127 patients with stage II osteosarcoma who showed more than a 15% volume change after chemotherapy were retrospectively reviewed. Patients were divided into two groups depending on whether tumors increased or decreased in size. Fisher's exact test was performed to analyze correlations between tumor size changes and clinicopathological variables. Five-year metastasis-free survival and overall survival were evaluated using univariate and multivariate analyses.

RESULTS

A total of 71 patients (55.9%) showed a decrease in tumor volume, and 56 patients (44.1%) showed an increase. An increase in tumor volume after neoadjuvant chemotherapy was found to be positively correlated with a poor histological response and subsequent metastasis. Univariate analysis identified the following parameters as poor prognostic factors: age < or = 15 years (P = 0.03), American Joint Committee on Cancer (AJCC) stage IIB (P = 0.02), a subtype other than osteoblastic (P < 0.01), a poor histological response (P < 0.001), and increased tumor volume after preoperative chemotherapy (P < 0.0001). Multivariate analysis revealed that AJCC stage IIB (P = 0.006) and an increase in tumor volume after preoperative chemotherapy (P < 0.001) both independently shortened metastasis-free survival. However, a poor histological response lost its prognostic significance (P = 0.34).

CONCLUSIONS

Increased tumor volume after neoadjuvant chemotherapy independently shortened metastasis-free and overall survival in AJCC stage II osteosarcoma patients. Tumor volume changes may serve as a basis for risk-adapted therapy when used in combination with other prognostic factors.

Prognostic factors and outcomes for osteosarcoma: an international collaboration

We aimed to evaluate the prognostic significance of traditional clinical predictors in osteosarcoma through an international collaboration of 10 teams of investigators (2680 patients) who participated. In multivariate models the mortality risk increased with older age, presence of metastatic disease at diagnosis, development of local recurrence when the patient was first seen, use of amputation instead of limb salvage/wide resection, employment of unusual treatments, use of chemotherapeutic regimens other than anthracycline and platinum and use of methotrexate. It was also influenced by the site of the tumour. The risk of metastasis increased when metastatic disease was present at the time the patient was first seen and also increased with use of amputation or unusual treatment combinations or chemotherapy regimens not including anthracycline and platinum. Local recurrence risk was higher in older patients, in those who had local recurrence when first seen and when no anthracycline and platinum were used in chemotherapy. Results were similar when limited to patients seen after 1990 and treated with surgery plus combination chemotherapy. This large-scale international collaboration identifies strong predictors of major clinical outcomes in osteosarcoma.

Prognostic nomogram for predicting the 5-year probability of developing metastasis after neo-adjuvant chemotherapy and definitive surgery for AJCC stage II extremity osteosarcoma

BACKGROUND

In this retrospective study, we developed and internally validate a nomogram for predicting 5-year metastasis probability for nonmetastatic extremity osteosarcoma.

PATIENTS AND METHODS

We reviewed 365 osteosarcoma patients treated at our institute from 1990 to 2003. Clinicopathologic variables were recorded. Multivariate analysis using Cox proportional hazards regression was done and this Cox model was used as the basis for the nomogram.

RESULTS

By American Joint Committee on Cancer (AJCC) staging system, 141 patients (38.6%) were stage IIA and 224 (61.4%) were stage IIB. Multivariate Cox model identified patient age at diagnosis, tumor size, humeral location, and tumor necrosis rate after chemotherapy as correlated with metastasis-free survival. The degree of contribution of each covariate to the total point was tumor location, tumor necrosis rate, maximal tumor diameter, and age in decreasing order. The concordance index for the model was 0.78. Nomogram discrimination was superior to that of AJCC stage (concordance index 0.78 versus 0.68; P = 0.02) and histologic response grouping (concordance index 0.78 versus 0.69; P = 0.0004).

CONCLUSIONS

We devised a nomogram for nonmetastatic osteosarcoma that proposes improved estimates of metastasis over AJCC staging system or tumor necrosis rate. We suggest that this nomogram allows individualized risk assessments and could be used as the basis for risk-adapted therapy.

Postoperative infection and survival in osteosarcoma patients

The clinical impact of postoperative deep infection on survival remains controversial in osteosarcoma patients. The authors identified 31 osteosarcoma patients that developed a deep infection within 1 year of operation between 1990 and 2003, and compared clinicopathologic characteristics of 31 patients that developed an infection with those of 316 patients that did not. For survival analysis, 62 noninfected patients matched for prognostic factors such as histologic response, tumor size, and location were also selected. In infected patients, although it was not significant due to the small patient numbers, good response to preoperative chemotherapy and a proximal tibial location were frequently observed. No local recurrence developed in infected patients. Five-year overall and metastasis-free survival rates for the 31 infected patients were as high as 89% and 73%, respectively. However, after matching for clinical factors, no survival difference was noted between infected and noninfected patients. Deep infection has a multifaceted effect on patients. However, the present study suggests that the reported positive effect on survival is likely to be related to the clinical characteristics of infected patients rather than an antitumor effect due to the infection. Further investigations are needed to clarify the precise effects of infection.

Relationships between plain-film radiographic patterns and clinicopathologic variables in AJCC stage II osteosarcoma

OBJECTIVE

In this retrospective study, we assessed the plain-film radiographic patterns of American Joint Committee on Cancer (AJCC) stage II osteosarcoma and analyzed the relationship between these patterns and clinicopathologic variables.

MATERIALS AND METHODS

We retrospectively reviewed 347 patients with AJCC stage II osteosarcoma who were treated at our institute. Patients were divided into three groups based on radiographic patterns, i.e., osteoblastic, osteolytic, and mixed. Fisher's exact chi-square test was performed to analyze correlations between radiographic patterns and clinicopathological variables.

RESULTS

One hundred and eighty-eight patients had an osteoblastic tumor, 101 had an osteolytic tumor, and 58 had a mixed tumor. Tumors with an osteoblastic pattern showed a tendency to have the following characteristics: AJCC stage II-B, osteoblastic or chondroblastic subtype, and no pathologic fracture. Conversely, osteolytic tumors were frequently of AJCC stage II-A, had a fibroblastic or rare subtype, and were associated with a pathologic fracture. Finally, mixed tumors were frequently found in men. No survival difference was found according to radiographic pattern.

CONCLUSIONS

Plain-film radiographic patterns were found to be related with clinicopathological features. We believe that it could be used to provide valuable information for treatment decision-making in cases of high-grade extremity osteosarcoma.