Establishment, Maintenance, and Performance of the Cooperative Osteosarcoma Study Group (COSS)

Impact of anthracycline-based chemotherapy on RB1 gene methylation in peripheral blood leukocytes and biomarkers of oxidative stress and inflammation in sarcoma patients

PURPOSE

We investigated the impact of anthracycline-based chemotherapy on methylation status of RB1 gene in peripheral blood leukocytes together with parameters of oxidative stress and inflammation in sarcoma patients.

PATIENTS/METHODS

Blood samples were collected from 51 consecutive newly diagnosed sarcoma patients admitted to University Hospital Center Zagreb (Zagreb, Croatia) for first-line chemotherapy before the first cycle and post-chemotherapy. Methylation and copy number variation (CNV) of leukocyte RB1 gene were assessed using MS-MLPA probes. In addition, in blood samples, parameters of oxidative stress (ROS, MDA, SOD, and GSH) and inflammation (CRP, WBC, and NBC) were followed.

RESULTS

In pre-chemotherapy samples, no CNVs and aberrant methylation of CpG106 promoter region of RB1 gene were detected; however, one patient had hypermethylation (by approximately 10%) of imprinted locus CpG85 in intron 2 of RB1 gene. In addition, a very good correlation of the tumor burden and CRP and tumor burden and GSH was found. The anthracycline-based chemotherapy reverts methylation of RB1 gene-imprinted locus CpG85 to normal level. Moreover, inflammation and oxidative stress parameters such as CRP, WBC, ROS, and MDA were significantly decreased in post-chemotherapy samples.

CONCLUSION

This single-centered study on a cohort of consecutive sarcoma patients indicates that sarcoma patients can have aberrant germline DNA methylation and confirms the relationship of tumor burden with inflammation and oxidative stress. The applied chemotherapy protocols reverted RB1 gene methylation to normal level and decreased the level of inflammation and oxidative damage, thus indicating chemotherapy benefit to the patient's health status.

Osteosarcoma Arising as a Secondary Malignancy following Treatment for Hematologic Cancer: A Report of 33 Affected Patients from the Cooperative Osteosarcoma Study Group (COSS)

PURPOSE

Osteosarcoma may arise as a secondary cancer following leukemias or lymphomas. We intended to increase the knowledge about such rare events.

PATIENTS AND METHODS

We searched the Cooperative Osteosarcoma Study Group's database for individuals who developed their osteosarcoma following a previous hematological malignancy. The presentation and treatment of both malignancies was investigated, and additional neoplasms were noted. Outcomes after osteosarcoma were analyzed and potential prognostic factors were searched for.

RESULTS

A total of 33 eligible patients were identified (male: 23, female: 10; median age: 12.9 years at diagnosis of hematological cancer; 20 lymphomas, 13 leukemias). A cancer predisposition syndrome was evident in one patient only. The hematological cancers had been treated by radiotherapy in 28 (1 unknown) and chemotherapy in 26 cases, including bone-marrow transplantation in 9. The secondary bone sarcomas (high-grade central 27, periosteal 2, extra-osseous 2, undifferentiated pleomorphic sarcoma of bone 2) arose after a median lag-time of 9.4 years, when patients were a median of 19.1 years old. Tumors were considered radiation-related in 26 cases (1 unknown). Osteosarcoma-sites were in the extremities (19), trunk (12), or head and neck (2). Metastases at diagnosis affected eight patients. Information on osteosarcoma therapy was available for 31 cases. All of these received chemotherapy. Local therapy involved surgery in 27 patients, with a good response reported for 9/18 eligible patients. Local radiotherapy was given to three patients. The median follow-up was 3.9 (0.3-12.0) years after bone tumor diagnosis. During this period, 21 patients had developed events as defined, and 15 had died, resulting in 5-year event-free and overall survival rates of 40% (standard error: 9%) and 56% (10%), respectively. There were multiple instances of additional neoplasms. Several factors were found to be of prognostic value (p < 0.05) for event-free (osteosarcoma site in the extremities) or overall (achievement of a surgical osteosarcoma-remission, receiving chemotherapy for the hematologic malignancy) survival.

CONCLUSIONS

We were able to prove radiation therapy for hematological malignancies to be the predominant risk factor for later osteosarcomas. A resulting overrepresentation of axial and a tendency towards additional neoplasms affects prognosis. Still, selected patients may become long-term survivors with appropriate therapies, which is an argument against therapeutic negligence.

What Is the Impact of Multimodal Treatment in Patients with Leiomyosarcoma of Bone? A Multicenter Study of 35 Patients with an Ultra-Rare Tumor Entity

Primary leiomyosarcoma of bone (LMSoB) is extremely rare, comprising only <0.7% of primary malignant bone tumors, and is therefore considered an ultra-rare tumor entity. There is currently no consensus as to whether therapeutic strategies should be based on the biological characteristics of soft tissue leiomyosarcoma or on primary tumor localization in the bone. The use of perioperative chemotherapy and its effectiveness in this rare tumor entity remains unclear. We aimed to evaluate the impact of different treatment approaches in a multicenter setting with a total of 35 patients included. The 5-year overall survival (OS) was 74%. Patients with localized disease undergoing surgery had a significantly higher 5-year OS compared to patients who did not undergo surgical treatment (82% vs. 0%, p = 0.0015). Axial tumor localization was associated with worse event-free survival (EFS) probability (p < 0.001) and OS (p = 0.0082). A high proportion of our patients developed secondary metastases. Furthermore, the perioperative chemotherapy protocols applied to our patients were not associated with an improved EFS or OS. Therefore, the benefit of perioperative chemotherapy in LMSoB needs to be further investigated, and the choice of agents still needs to be clarified.

Beyond 5-year survival. A report from the Cooperative Osteosarcoma Study Group (COSS)

PURPOSE

Prognostic factors have been well described for osteosarcoma, but analyses evaluating the further course of long-term survivors are lacking. We used the large database of the Cooperative Osteosarcoma Study Group (COSS) to perform such an analysis.

PATIENTS AND METHODS

The COSS database 1980-04/2019 was searched for 5-year survivors of primary high-grade central osteosarcoma of the extremities or trunk. Identified patients were analyzed for their further survival outcomes, assessing potentially prognostic and predictive factors already evident at initial disease presentation and treatment as well as their disease course during the first 5 years of follow-up.

RESULTS

Two thousand and nine former eligible patients were identified (median age at initial diagnosis 15.1 (2.5-63.0) years; male vs. female 1149 (57.2%) vs. 860 (42.8%); extremities vs. trunk 1927 (95.9%) vs. 82 (4.1%); extremity primaries <1/3 vs. ≥1/3 of the involved bone 997 (67.8%) vs. 474 (32.2%) (456 unknown); localized vs. primary metastatic 1881 (93.6%) vs. 128 (6.4%); osteosarcoma as a secondary malignancy 41/2009 (2.0%)). Therapy starting by chemotherapy versus primary surgery 1860 (92.6%) versus 149 (7.4%); definitive tumor surgery by limb salvage versus ablative 1347 (67.0%) versus 659 (1 no surgery, 2 unknown); tumor response to preoperative chemotherapy documented for 1765 (94.9%) patients receiving neoadjuvant chemotherapy, good (<10% viable tumor) versus poor 1130 (64.0%) versus 635 (36.0%), local radiotherapy documented for 19 (0.9%) tumors. Recurrence during preceding 5 years no versus yes 1681 (83.7%) versus 328 (16.3%). Median follow-up starting 5 years after initial diagnosis 6.1 (0.002-32.2) years; 1815 survivors and 194 deaths. Overall survival after another 5/10/15/20 years 91.7%/88.9%/85.8%/83.4% for all patients; 97.5%/95.2%/92.4%/89.9% if in remission years 1-5 versus 62.7%/57.3%/53.0%/51.2% if recurrence year 1-5 (p < 0.001). Significant predictors of survival for all patients age at diagnosis (p = 0.038), tumor site (p = 0.030), having experienced the osteosarcoma as secondary malignancy (p < 0.001), tumor response to preoperative chemotherapy (p = 0.002). Multivariate Cox regression testing possible for 1759 (87.6%) patients with complete dataset: Having had a recurrence in years 1-5 (p < 0.001), older age at diagnosis (p = 0.009), and osteosarcoma as secondary malignancy (p = 0.013) retained significance.

DISCUSSION

Highly important predictors of death such as the extent of tumor response to chemotherapy no longer remain valid after 5-year survival. The individual history of malignancies and their outcomes seems to gain pivotal importance.

CONCLUSION

This benchmark analysis clearly defined risk factors for the further course of 5-year survivors from osteosarcoma. It argues for large disease-oriented databases as well as for very long follow-up periods. Novel findings will most likely require innovative statistical models to analyze such cohorts.