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Osteosarcoma Relapse After Combined Modality Therapy: An Analysis of Unselected Patients in the Cooperative Osteosarcoma Study Group (COSS)
http://www.100md.com 《临床肿瘤学》
     the Universittsklinikum Münster, Klinik und Poliklinik für Kinder- und Jugendmedizin, Pdiatrische Hmatologie und Onkologie

    Universittsklinikum Münster, Medizinische Klinik und Poliklinik A

    Universittsklinikum Münster, Klinik und Poliklinik für Thorax-, Herz- und Gefchirurgie, Münster

    Krankenhaus Grohansdorf, Zentrum für Pneumologie und Thoraxchirurgie, Grohansdorf

    Universittsklinikum Düsseldorf, Klinik für Kinder-Onkologie, -Hmatologie und -Immunologie, Düsseldorf

    Universittsklinikum Hamburg-Eppendorf, Universittsklinik und Poliklinik für Kinder- und Jugendmedizin, Abteilung für Pdiatrische Radiologie

    Universittsklinikum Hamburg-Eppendorf, Klinik und Poliklinik für Pdiatrische Hmatologie und Onkologie

    Radiologische Privat-Praxis Raboisen

    Universittsklinikum Hamburg-Eppendorf, Klinik und Poliklinik für Radiologie, Abteilung für Strahlentherapie und Radioonkologie, Hamburg

    Zentrum für Kinderheilkunde und Jugendmedizin des Klinikums der Johann Wolfgang Goethe-Universitt, Klinik für Kinderheilkunde III, Pdiatrische Onkologie, Hmatologie und Hmostaseologie, Frankfurt

    Olgahospital Stuttgart, Pdiatrie 5 (Onkologie, Hmatologie und Immunologie), Stuttgart, Germany

    Orthopdische Universittsklinik Balgrist, Zürich

    Kantonsspital Basel, Institut für Pathologie, Basel, Switzerland

    Universittsklinik für Orthopdie, Allgemeines Krankenhaus Wien, Vienna

    St Anna Kinderspital, Vienna, Austria

    ABSTRACT

    PATIENTS AND METHODS: Five hundred seventy-six consecutive patients who had achieved a first complete surgical remission (CR) during combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group (COSS) protocols and then developed recurrent osteosarcoma were analyzed (median time from biopsy to relapse, 1.6 years; range, 0.1 to 14.3 years). There were 501 patients with metastases, 44 with local recurrences, and 31 with both. Metastases involved lungs (469 patients), bones (90 patients), and/or other sites (54 patients).

    RESULTS: After a median follow-up of 1.2 years for all patients and 4.2 years for survivors, actuarial overall survival (OS) rates at 2, 5, and 10 years were 0.38, 0.23, and 0.18, respectively. Five-year OS was 0.39 for 339 patients with and 0.00 for 229 patients without a second surgical CR (P < .0001). A long time to relapse, a solitary lesion, and, in the case of pulmonary metastases, unilateral disease and the absence of pleural disruption, were of positive prognostic value in uni- and multivariate analyses, as were a second surgical CR and the use of second-line chemotherapy. Radiotherapy was associated with moderately prolonged survival in patients without a second CR. The very limited prognostic differences associated with the use of second-line chemotherapy appeared to be more pronounced with polychemotherapy.

    CONCLUSION: Time to relapse and tumor burden correlate with postrelapse outcome in osteosarcoma. Complete surgery is an essential component of curative second-line therapy. Chemotherapy, particularly chemotherapy with more than one agent, may contribute to limited improvements in outcome.

    INTRODUCTION

    In 2002, our group presented data on 1,702 consecutive patients with high-grade osteosarcoma.23 We now evaluate all recurrences developing in this cohort, a large, unselected group of osteosarcomas that are relapsing despite intensive chemotherapy and complete surgery. The aims of this study were to describe the presentation of recurrent osteosarcoma and the probability of long-term survival in heavily pretreated patients, to identify prognostic factors for postrelapse survival, and to evaluate therapeutic measures and their possible impact on outcome.

    PATIENTS AND METHODS

    This study is based on data submitted until December 2002. As of then, a first complete remission (CR), defined as macroscopically complete surgery, had been documented for 1,512 of 1,702 patients (185 macroscopic residue, 5 no data); 897 of 1,512 were in first CR, 39 patients had died of other (36 patients) or unknown (3 patients) causes. The remaining 576 consecutive, unselected patients suffered a relapse (local or metastatic). They form the basis of this study.

    Detection of Relapse

    Routine follow-up included serial clinical evaluations and x-rays of the chest and primary tumor site at specified intervals. Routine computed tomography scans or bone scans were not mandatory. On suspicion of relapse, appropriate imaging of the chest, the primary tumor site, and a bone scan were required. Relapse diagnosis was based on the treating institution’s assessment.

    Treatment Strategy for Relapsed Osteosarcoma

    Relapse therapy was not standardized; however, most protocols included general recommendations. In addition, the COSS study center was available for guidance. Surgical removal of all detectable tumor foci was recommended whenever feasible. The decision to use second-line chemotherapy and the choice of drugs were left to the discretion of the treating physician. COSS suggested chemotherapy for all but late, solitary pulmonary metastases, and from approximately 1990, to include carboplatin and etoposide if chemotherapy was considered. The protocols did not include recommendations regarding radiotherapy.

    Data Collection and Definition of Variables

    Data concerning patient demographics, tumor characteristics at initial diagnosis, and first-line therapy was collected prospectively and coded as described previously by Bielack et al.23 First-line chemotherapy was reviewed, with particular attention to doxorubicin, methotrexate, cisplatin, and ifosfamide. Follow-up information collected prospectively included the date and site of first relapse, the date the patient was last known to be alive, and for deceased patients, the date and cause of death. Further details of relapse presentation, treatment, and outcome were collected retrospectively from status report forms, radiology, pathology, and surgery reports, progress letters, and telephone notes available at the data center. The relevant information from the COSS database and the study charts of all 576 patients were reviewed twice by two of the authors (B.K.-B., S.S.B.), and the following variables were coded: time to relapse—interval from diagnostic biopsy until relapse; number of lesions—solitary = single lesion, multiple = ≥ two lesions, based on the largest number reported, regardless of the method used for detection; site of relapse—local, metastatic, or combined; metastases—lung, distant bone, or other; lung metastases—unilateral or bilateral; pleural disruption—lung metastases extending by contiguous growth into the pleural cavity, chest wall, diaphragm, or mediastinum, or causing a malignant pleural effusion; treatment of relapse: surgery—attempt to remove tumor, regardless of its success; second CR—macroscopically complete surgical removal of all tumor (based on the treating institution’s assessment and, if present, surgery and pathology reports); chemotherapy for first relapse—cytostatic therapy administered between diagnosis of first relapse and second relapse or last follow-up in remission (for patients with second CR), or until last follow-up or death (for patients without second CR). Drugs used were recorded and categorized. The use of radiotherapy was also recorded.

    Statistics

    All patients were evaluated retrospectively on an intention-to-treat basis. All parameters were first investigated by univariate techniques. {chi}2 analysis was used to compare unrelated samples. Follow-up periods were calculated from the date relapse was diagnosed to the date of last documented information. Overall survival was calculated to the date of patient death from any cause, and event-free survival until second relapse or death, whichever occurred first. Patients without a second CR were assumed to have suffered an event on day 1. Survival analyses were performed using the Kaplan-Meier method.28 The log-rank test was used to compare survival curves.29 Multivariate analyses of survival were completed using the Cox proportional hazards model.30 Only variables that presented with a significant prognostic value in univariate analysis and relapse therapy (surgery, chemotherapy, or radiotherapy) were included in the multivariate models. All P values were two-sided and a P value of less than .05 was significant.

    RESULTS

    The median time to relapse was 1.6 years (range, 0.1 to 14.3 years). Five hundred forty-three relapses (94.3%) occurred within 5 years from biopsy, 29 (5.0%) occurred in years 6 to 10, and 4 (0.7%) thereafter (Table 2). "Late" relapses (> 18 months) correlated with older age at diagnosis (≥ 16 years; {chi}2 test, P = .040), small primary tumors (P = .023), lack of primary metastases (P = .024), first-line chemotherapy with all four drugs (P = .017), and good response to first-line chemotherapy (P = .003); and recurrences were more likely to be solitary (P < .001) and unilateral (P < .001).

    Recurrence was solitary in 216 patients (38.8%), and multiple lesions were reported in 341 patients (61.2%). Solitary relapses were more likely to occur in patients without primary metastases (P = .010), and more likely to be late relapses (P = .001), and less likely to disrupt the pleura (P = .001). There was no significant correlation between first-line response and the number of lesions at relapse (P = .060).

    Altogether, there were 501 metastatic relapses (87.0%), 44 local relapses (7.6%), and 31 combined relapses (5.4%). Lung metastases were part of 469 relapses (81.4%); lung metastases were the only site of recurrence in 373 patients (64.8%), they were unilateral in 227 patients (52.1% of patients with pulmonary involvement), and bilateral in 209 patients (47.9%; laterality was unknown in 33 patients). Lung metastases were reported to have disrupted the pleura in 66 patients. Distant bones were involved in 90 (15.6%) of 576 relapses; they were the only site of recurrence in 45 patients (7.8%). "Other" metastases were reported in 54 patients (9.4%), and as the only site of recurrence in only 12 patients (2.1%). Sites involved by extrapulmonary/extraosseous metastases were (multiple mentions possible): regional (five patients) and distant (25 patients; 22 intrathoracical, three abdominal, one cervical) lymph nodes, CNS (eight patients), soft tissues (eight patients), pleura (five patients), liver (four patients), kidney (one patient), pericardium (one patient), stomach (one patient), retina (one patient), and regional node or soft tissue (one patient).

    Treatment of Relapse

    Tumor-directed therapy was reported for 511 of 576 relapses (51 none, 14 insufficient information). Four hundred twenty-two patients had surgery, and 339 of these patients achieved a second CR. Both surgery and a second CR were more likely to have been reported in patients with late or solitary relapses than in others (P < .001). Chemotherapy was reported for 381 of 576 relapses (173 none, 22 no data). Information about drugs administered was available for 376 of 381 patients. Of these, 43 patients (11.4%) were treated with a single agent and 333 patients (88.6%) with two or more. In addition to the agents detailed in Table 3, chemotherapy included actinomycin in 27 patients (7.2%), bleomycin in 21 patients (5.6%), vinca alkaloids in 18 patients (4.8%), dacarbazine in two patients, and fludarabine, paclitaxel, and mitomycin in one patient each. The use of second-line chemotherapy correlated with good response to first-line chemotherapy (P = .022), multiple lesions at relapse (P = .001), and bilateral pulmonary involvement (P = .001), but not time to relapse (P = .953).

    Thirty-three of the 58 patients who received external-beam radiotherapy also had surgery, but only 10 patients achieved a second remission. An additional four patients received radioisotope treatment with Samarium-153-EDTMP.

    Postrelapse Survival

    Follow-up information was available for 575 of 576 patients. After a median of 1.2 years (range, 2 days to 18.4 years) for all patients and 4.2 years for 148 survivors (range, 5 days to 18.4 years), actuarial overall survival at 5 and 10 years was 0.23 (SE, 0.02) and 0.18 (SE, 0.02), respectively (Fig 1). A second relapse developed in 249 of 339 patients that were surgically disease free. The median time from first to second relapse was 0.8 years (range, 3 weeks to 9.8 years), shorter than the first relapse-free interval in 205 patients (82.3%) and longer in 44 patients (17.6%). Among the 148 survivors, 82 were in continuous second CR, with event-free survival rates of 0.13 (SE, 0.01) and 0.11 (SE, 0.02) at 5 and 10 years, respectively (Fig 1). Thirty-seven patients were alive in later CR (third CR, 24; fourth CR, seven; fifth CR, four; seventh CR, one; eighth CR, one) and 29 patients were alive with disease (without second CR, 14 patients; in second CR, eight patients; in third CR, six patients; in fourth relapse, one patient). Four hundred twenty-seven of 576 patients died (median, 0.9 years after first relapse; range, 2 days to 13.0 years); 397 patients of osteosarcoma and 19 of other causes, seven of these patients were in second CR and two in third CR. Nine of 19 patients died of sepsis and/or multiorgan failure; two each as a result of perioperative complications, thromboembolic events, or cardiomyopathy; one each as a result of acute myelogenous leukemia, pulmonary fibrosis, and anorexia nervosa. The cause of death was not reported for 11 patients (10 with uncontrolled osteosarcoma, one in CR at previous follow-up).

    Prognostic Factors

    Of the factors associated with initial disease presentation and treatment, only response to first-line chemotherapy correlated with survival (log-rank P = .048; Table 1). Patients with early relapses fared significantly worse than those with late relapses, patients with multiple lesions fared worse than those with solitary relapses, patients with bilateral lung metastases fared worse than those with unilateral lung metastases, and patients with pleural disruption by lung metastases fared worse than those without (P < .0001, for all; Table 2). Among treatment-related variables, surgery and a second surgical CR correlated with improved overall survival (P < .0001, for both; Table 2; Fig 2). The median survival period for patients achieving a second CR was 2.2 years (range, 5 days to 18.4 years), compared with 0.6 years for other patients (range, 2 days to 3.7 years).

    Chemotherapy use correlated with overall survival in patients who did not achieve a second CR (P = .0001), and with event-free survival in those patients who did (P = .016). When multidrug chemotherapy was compared with no chemotherapy or single-agent chemotherapy, multidrug chemotherapy correlated with overall survival in the total cohort (P = .012; Table 3; Fig 3). Radiotherapy was associated with prolonged survival only in the subgroup of patients without a second CR (P = .0001; Table 3).

    Multivariate Analyses

    Tumor response to first-line preoperative chemotherapy did not retain significance in the multivariate models, but time to relapse, the number of lesions (except in patients without a second CR), and pleural disruption were significant (Table 4). Failure to operate was the strongest negative prognostic factor for the entire cohort, and retained significance even in patients who did not achieve a second surgical CR. Chemotherapy was associated with better overall survival in the model for the entire cohort and in the model for patients without second CR, and with better event-free survival in the model for patients with a second CR. Radiotherapy was not significant in any multivariate model.

    DISCUSSION

    Presentation and distribution data of recurrent osteosarcoma were the same as that reported by others. The median time from diagnosis to first relapse—1.6 years—was almost identical to that described in other current reports,11,12,32 but approximately half a year shorter than the median time of 23 months from first CR to first relapse reported in a study of 162 patients by the Rizzoli Institute.10 In the latter series and ours, some very late relapses developed after more than 10 years, implying that tumor-directed follow-up should be extended well into the second decade.

    Our series included both local and systemic recurrences. The lung, involved in more than 80% of all patients, and as the only site in nearly two thirds of all patients, was by far the most frequently involved site. Similar rates have been reported by others.3,4,6,8,10-12,17,32 Of note, only 20% of patients with lung metastases had additional disease, in contrast to half of those with bone metastases, and most of those with other metastases. As was observed in other reports,8 early relapses were particularly likely to be multifocal in our study, and in the case of lung metastases, bilateral, or to disrupt the pleura.

    While various chemotherapy protocols had been used for first-line chemotherapy in other studies, all had included intensive multidrug regimens.23-27 Accordingly, 90% of the osteosarcomas from our series had already been exposed to at least three of the agents considered most active against the disease, namely high-dose methotrexate, doxorubicin, cisplatin, and ifosfamide. Nevertheless, treatment for recurrence was once again rather intensive. Three quarters of all patients had surgery and two thirds received second-line chemotherapy, mostly with multiple agents. Despite such comprehensive treatment, the long-term postrelapse survival rate was disappointingly low, with 5- and 10-year survival estimates of only 0.23 and 0.18, respectively. Comparison of these survival estimates with others is hampered by the fact that basically all other series have used narrower selection criteria. Reports from the surgical literature, for instance, tend to be restricted to patients with lung metastases advancing to thoracotomy,5,22,31,33-37 thereby excluding poor-risk patients with extensive disease. Still, our results fit well into the overall picture, with only approximately one quarter of patients surviving for 5 years or longer.3-12,16,18 Even these low survival estimates should by no means be confused with cure, as late tumor-related deaths do occur.

    Several independent risk factors are associated with the probability to develop osteosarcoma recurrences. In the COSS trials, these factors included axial site and large size of the primary tumor, and primary metastases.23 Interestingly, none of these factors predicted for outcome after relapse. Poor response to first-line chemotherapy is another robust predictive factor for relapse.2,23 While good responders had better postrelapse survival, response to first-line chemotherapy was not of independent prognostic value for outcome after recurrence. Rather, the benefit for relapsing good responders seemed to have been mediated by longer times to recurrence.

    Others have reported conflicting results regarding time to relapse, with some3,9-11,15,33,38 demonstrating and others5,7,8,17,19,31 failing to detect an association with postrelapse survival. Our results clearly confirm that patients with late relapses fare better, but their survival curve does not reach a plateau and the ultimate course of disease tends to be relentless in most cases.

    The second presenting factor which strongly correlated with outcome in our series was the number of lesions, confirming previous observations made using various cut-off points.5,8-12,15,31,38 Again in agreement with others,5,10-12,33 and pointing out that more disease implies inferior outcome, bilateral pulmonary metastases were associated with a worse prognosis than unilateral disease. Extrapulmonary recurrence is often believed to carry a particularly grave prognosis. Our results imply that it is not the extrapulmonary site as such, but rather the high likelihood that extrapulmonary metastases are part of a disseminated disease process that leads to this impression. Other recent reports have also demonstrated that metachronous osteosarcoma limited to distant bone is not associated with a bleak prognosis.39-41

    The location and number of lesions cannot be viewed independently from resectability. As observed in many smaller series,4-22 we found long-term survivors exclusively among patients who achieved a second surgical remission. This closely parallels the situation known from first-line treatment23 and underscores the dire need for effective alternate therapies in inoperable osteosarcoma. Owing to the nature of the data on which this report is based, the definition of second CR, macroscopic removal of all known tumor sites as reported by the treating institution, was not strict. Goorin et al4 have used much more stringent criteria, namely removal of macroscopic disease, no microscopic disease at resection margins, and no histologic evidence of pleural disruption by tumor. The use of such rigid criteria would narrow down considerably the number of patients assumed to have achieved a second CR, possibly allowing a better definition of the subgroup from which survivors will originate.

    The role of second-line chemotherapy for relapsed, intensively pretreated osteosarcoma is not as obvious as that of surgery. The few previous reports that suggested better outcomes with chemotherapy did so only for subgroups of patients or retrospectively defined regimens. Norwegian investigators8 reported that "adequate salvage chemotherapy" had independent predictive value for improved overall survival in 60 patients with distant metastases. In the Rizzoli series,10 better overall survival with chemotherapy was limited to the subgroup of patients unable to achieve a second remission. However, because most patients treated without chemotherapy for a first relapse will doubtlessly receive chemotherapy for subsequent recurrences, analyses of overall survival unwittingly compare immediate with delayed chemotherapy rather than chemotherapy with observation. This bias does not apply to analyses of event-free survival, which stop at the second recurrence. By performing such analyses, we were indeed able to expand previous observations of a positive correlation between second-line chemotherapy and outcome to patients achieving a second surgical remission, suggesting an adjuvant effect, albeit limited, even in these heavily pretreated patients. The adjuvant effect is much less obvious than that of first-line treatment, and may easily be missed when analyzing small cohorts. Owing to the retrospective nature of our analysis, we cannot exclude that some of the benefit attributed to chemotherapy was due to selection bias. However, we might even have underestimated the efficacy of chemotherapy, as the patients that received chemotherapy were more likely to have presented with more extensive recurrences. Our data does not allow conclusions about the relative efficacy of individual agents, but suggests that treatment with more than one drug might be preferable.

    We are not aware of previous systematic analyses of radiotherapy for relapsed osteosarcoma. In the COSS series, radiotherapy was almost exclusively administered to patients failing to achieve a second CR. In this subgroup, similar to our group’s experience with unresectable pelvic or vertebral osteosarcoma,42,43 radiotherapy was associated with a limited prolongation of survival. Again, the retrospective nature of the analysis did not allow us to conclude whether this was an effect of radiotherapy or whether other factors, such as patient selection, were responsible.

    In conclusion, our results, derived from a large, unselected cohort of intensively pretreated patients with long-term follow-up, confirm the poor prognosis of recurrent osteosarcoma. A short time to relapse, recurrences involving more than one lesion, and, in the case of lung metastases, bilateral disease and pleural disruption, are negative prognostic factors. Complete surgery can be a prerequisite for cure. Second-line chemotherapy, especially chemotherapy with more than one agent, seems to contribute to limited improvements of outcome. Patients with unresectable disease may benefit from radiotherapy. Collaborative, prospective efforts are warranted to further elucidate the role of specific interventions for osteosarcomas that relapse despite adequate first-line treatment, and to evaluate innovative approaches.

    Appendix

    Authors’ Disclosures of Potential Conflicts of Interest

    Acknowledgment

    We thank all of the patients who contributed to the COSS studies and acknowledge the physicians, nurses, data managers, and support staff of the collaborating centers for their active participation. We also thank Silke Flege and Merle Eselgrim for their contributions to data management and evaluation.

    NOTES

    Supported in part by Deutsche Krebshilfe.

    Presented in part at the 39th Annual Meeting of the American Society of Clinical Oncology, Chicago, IL, May 31-June 3, 2003, and at the 36th Congress of the International Society of Paediatric Oncology, Oslo, Norway, September 16-19, 2004.

    Authors’ disclosures of potential conflicts of interest are found at the end of this article.

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