Efficacy of topotecan plus vincristine and doxorubicin in children with recurrent/refractory rhabdomyosarcoma

Pediatric rhabdomyosarcoma with bone marrow metastasis

BACKGROUND

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of adolescence and childhood. Although most patients with localized RMS are cured, outcome of those with metastatic disease remains unsatisfactory. RMS with bone marrow (BM) metastasis accounts for approximately 6% of all cases with RMS and has a 3-year event-free survival of 14%. Our study aims to describe our institution's experience of patients with metastatic RMS with BM involvement.

METHODS

This was a single-institution retrospective study from Memorial Sloan Kettering Kids, a tertiary pediatric oncology center. Patients with RMS who were diagnosed with BM metastasis between 1998 and 2018 were identified from pathology reports.

RESULTS

For patients with RMS and BM positivity at diagnosis (N = 27), the median survival was 1.5 years. The 1-, 2-, and 3-year overall survival (OS) were 81%, 32%, and 20%, respectively. There is one long-term (defined as >4 year) survivor who is still alive 14.9 years after diagnosis despite two metastatic recurrences. An Oberlin status of 4 that included BM metastasis portended a 3-year OS of 0%.

CONCLUSIONS

Although most patients will respond to initial therapy, BM metastasis at the time of diagnosis lends a near-fatal diagnosis in pediatric patients with RMS. Novel therapies are desperately needed to consolidate their initial remission.

Topotecan/carboplatin regimen for refractory/recurrent rhabdomyosarcoma in children: Report from the AIEOP Soft Tissue Sarcoma Committee

INTRODUCTION

From 2002 to 2011, the Italian Soft Tissue Sarcoma Committee explored a combination of topotecan and carboplatin as a second-line strategy for children with resistant or relapsing rhabdomyosarcoma.

METHODS

Patients received two blocks of topotecan 2 mg/m² on days 1, 2, and 3, and carboplatin 250 mg/m² on days 4 and 5, followed by alternating blocks of topotecan-cyclophosphamide and carboplatin-etoposide for a total of six courses with 3-week intervals. Tumor response was assessed after two cycles, and local control was implemented when feasible.

RESULTS

A total of 38 patients were included in this study: 18/38 had alveolar rhabdomyosarcoma (RMS), 10/38 had metastatic disease at diagnosis, 8/38 had tumor progression during first-line chemotherapy, 21/38 had locoregional relapses, and 9/38 had distant relapses. Thirty-two patients could be assessed for tumor response to topotecan-carboplatin, and 9 (28%) showed a complete or partial response. Twenty-four patients experienced grade IV hematologic toxicity, while transient grade 1 tubulopathy, grade 3 mucositis, transient grade 2 nephrotoxicity, and a grade 2 decline in cardiac function occurred in one patient each. The 5-year overall and progression-free survival rates were 17% and 14%, respectively.

CONCLUSION

the prognosis for children with resistant or relapsing RMS remains unsatisfactory. The topotecan-carboplatin regimen was well-tolerated. Though in case of late relapse the response rate was similar to those reported for other regimes, the result achieved remains unsatisfactory. New approaches, possibly including target agents, seem more attractive for future studies.

Relapse after localized rhabdomyosarcoma: Evaluation of the efficacy of second-line chemotherapy

PURPOSE

About one-third of patients with rhabdomyosarcoma relapse despite appropriate treatment and experience a poor outcome. Little meaningful improvement in the outcome of this disease has been observed over the last 30 years. There is no clear international recommendation concerning the use of salvage chemotherapy at relapse. A retrospective multicenter analysis was therefore conducted to analyze the efficacy of various second-line chemotherapy regimens in this setting.

METHODS

Forty-nine patients under the age of 18, with initially localized rhabdomyosarcoma, who relapsed after first complete remission, treated in three SFCE centers (Société Française des Cancers de l'Enfant) between 1995 and 2013, were analyzed.

RESULTS

First relapse occurred after a median interval of 22 months and remained localized in 71.4% of cases. All patients received second-line chemotherapy with an overall response to this salvage therapy of 39.1%. Best specific response rates were 73.3 and 42.9% for carboplatin/epirubicin/vincristine-ifosfamide/vincristine/etoposide (CEV/IVE) (15 patients) and vincristine/irinotecan ± temozolomide (VI[T]) (seven patients), respectively. Overall, 40 patients (81.6%) were then eligible for delayed local treatment (surgery and/or radiotherapy) and 30 of them (61.2%) achieved second complete remission. After a median follow-up of 5.4 years since the diagnosis of first relapse, 5-year overall survival is 49.4% (95% CI: 34.2-64.6).

CONCLUSION

Salvage chemotherapy plays a central role in the management of patients with relapsed rhabdomyosarcoma. CEV/IVE and VI(T) regimens can be recommended as neoadjuvant chemotherapy before local treatment for patients with relapsed rhabdomyosarcoma.

Topotecan plus cyclophosphamide in adults with relapsed or refractory pediatric-type sarcoma: a retrospective analysis from the German Sarcoma Medical Oncology Group (AIO)

BACKGROUND

To assess the efficacy and safety of topotecan and cyclophosphamide (TC) in adult patients with pediatric-type sarcoma subtypes who failed induction chemotherapy.

PATIENTS AND METHODS

Patients with pediatric sarcoma subtypes, refractory to or relapsed after at least one prior induction chemotherapy, inoperable, ECOG PS 0-2, with measurable, progressive disease (PD), adequate organ functions, who have been treated with TC combination were retrospectively analysed within the AIO and SAREZ/BMBF network.

RESULTS

Thirty-nine patients, median age 28 years (18-58), 14 females, 25 males, have been identified. All patients had received induction treatment according to (inter)national study protocols. Second-line TC was applied in 33 patients (≥3rd-line in 6 patients). Twenty-three patients had refractory disease (evidence of PD during induction chemotherapy); 8 patients experienced an early relapse within 6 months as well as 8 patients after more than 24 months (late relapse). A median of 3 cycles (range, 1-6) had been applied and antitumor activity was: CR 2.6 %, PR 7.9 %, and disease stabilisation (SD) 26.3 %. PR lasted 32.8 months and median duration in patients with SD was 5 months (range, 2.0-14.7). The 3/6-months progression-free rates were 43.2 and 18.9 %.

CONCLUSIONS

Limited activity was seen in adult pts with refractory or relapsed pediatric-type sarcomas with the regimen which has proven activity in pediatric patients. Adults with refractory small cell sarcoma appear to have a similar dismal outcome as seen in pts with common adult-type histologies; however, a subset of patients has achieved long-lasting remissions on TC resulting in long-term survival.

Molecular profiling of childhood cancer: Biomarkers and novel therapies

BACKGROUND

Technological advances including high-throughput sequencing have identified numerous tumor-specific genetic changes in pediatric and adolescent cancers that can be exploited as targets for novel therapies.

SCOPE OF REVIEW

This review provides a detailed overview of recent advances in the application of target-specific therapies for childhood cancers, either as single agents or in combination with other therapies. The review summarizes preclinical evidence on which clinical trials are based, early phase clinical trial results, and the incorporation of predictive biomarkers into clinical practice, according to cancer type.

MAJOR CONCLUSIONS

There is growing evidence that molecularly targeted therapies can valuably add to the arsenal available for treating childhood cancers, particularly when used in combination with other therapies. Nonetheless the introduction of molecularly targeted agents into practice remains challenging, due to the use of unselected populations in some clinical trials, inadequate methods to evaluate efficacy, and the need for improved preclinical models to both evaluate dosing and safety of combination therapies.

GENERAL SIGNIFICANCE

The increasing recognition of the heterogeneity of molecular causes of cancer favors the continued development of molecularly targeted agents, and their transfer to pediatric and adolescent populations.

Selecting multimodal therapy for rhabdomyosarcoma

Rhabdomyosarcoma is a typical tumor of childhood, characterized by a high grade of malignancy, local invasiveness and a marked propensity to metastasize, but also a generally good response to chemotherapy and radiotherapy. Multimodal therapy is essential to cure rhabdomyosarcoma patients, but different uses of surgery, radiotherapy and chemotherapy, and their intensity, need to be selected and modulated to different patient risk groups. This article attempts to give an account of the current treatment options, the open and debated issues and the potential novel strategies for the near future.

Pediatric urologic rhabdomyosarcoma

PURPOSE OF REVIEW

To review on the most significant and recent developments in basic research, diagnostic, and therapeutic aspects of genitourinary rhabdomyosarcomas (RMS) in children.

RECENT FINDINGS

Collaborative studies have dramatically improved therapy of genitourinary RMS with a remarkable improvement of survival. However, refractory or relapsed disease is still the most demanding challenge. Advances in our understanding of RMS molecular biology evolve new risk stratification and new therapeutic targets such as growth factors and their receptors. High-quality imaging is crucial and integrated fluorodeoxyglucose positron emission tomography/computed tomography significantly increased sensitivity. Alternative chemotherapeutical strategies were proven. Mutilating primary surgery should be avoided. Modern irradiation modalities with decrease of local radiation dose and, therefore, less long-term effects are new tools in the therapeutic arsenal of therapists.

SUMMARY

Therapy-associated morbidity after current RMS treatment can be significantly decreased by including modern strategies, especially in the field of irradiation. However, the follow-up is too short so far to make a distinct decision. The advances in understanding tumor biology may give rise to clinically relevant new therapeutic targets in the near future.