Replacing actinomycin-D with Carboplatin for newly diagnosed rhabdomyosarcoma

Efficacy and toxicity of carboplatin in the treatment of macroscopic mesenchymal neoplasia in dogs

Palliative chemotherapy options for dogs with macroscopic non-osseous mesenchymal tumours are limited. The purpose of this study was to assess the response rate of these tumours to carboplatin chemotherapy. Medical records of 28 dogs treated with carboplatin for macroscopic mesenchymal neoplasia between 1990 and 2022 were retrospectively reviewed. Sixteen dogs with soft tissue sarcoma and 12 dogs with haemangiosarcoma were included. Responses observed included one complete response and three partial responses, for an overall response rate of 14.2% (4/28) and median time to progression of 42 days (range 21-259 days). Responses were only seen in patients with haemangiosarcoma, for a response rate of 33.3% (4/12) and median time to progression for responders of 103 days (range 39-252 days). Median time to progression for dogs with metastatic disease was similar to those with only local disease (distant median: 44 days; local median: 23 days, p = 0.56). Dogs with chemotherapy-naïve disease were compared to dogs having received previous chemotherapy treatment and had a median time to progression of 75 days and 40.5 days respectively (p = 0.13). Twenty-two dogs experienced 48 adverse events, with most being grade 1 or 2 (79%). Carboplatin was well tolerated, with variable macroscopic anti-tumour activity and short response duration. Carboplatin may be an acceptable rescue option for dogs with macroscopic haemangiosarcoma, especially those patients that cannot receive doxorubicin.

Efficacy of replacing actinomycin-D with carboplatin in Ewing sarcoma consolidation treatment: Single-center experience

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ES treatment requires a multidisciplinary approach.

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Deficiencies in treatment affect the results negatively.

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This study showed that carboplatin can be used effectively as an alternative to actinomycin-D in the consolidation treatment.

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In addition, the presence of metastasis at diagnosis, tumor originating from the soft tissue, advanced stage and progressive disease are the poor prognostic factors in ES.

Background

Treatment of Ewing sarcoma (ES) requires multidisciplinary approach and deficiencies in treatment adversely affect the results. This study included patients diagnosed with ES and aimed to determine the factors affecting prognosis and investigate the efficacy of replacing actinomycin-D with carboplatin in consolidation treatment.

Methods

Eighty-two pediatric ES patients diagnosed at a single institution between 2005 and 2020 were retrospectively evaluated. Clinical and epidemiological features, treatment modalities, prognostic criteria, and overall survival (OS) rates of patients revieved. In consolidation treatment, 22 patients were treated with actinomycin-D and 32 patients with carboplatin (500 mg/m²/dose), 24 patients could not receive consolidation treatment. The 5- and 10-year OS rates of the patients were compared.

Results

The 5- and 10-year OS rates of the 82 patients with ES were 46% and 40%, respectively. The 5-year OS rates in the group with localized disease (n = 55) and metastasis (n = 27) at diagnosis were 54% and 26%, respectively (p = 0.006). When evaluated according to the consolidation treatment administered both the 5- and 10-year OS rates of the patients receiving actinomycin-D were 50%. The 5-year OS rate was 58% in the carboplatin group, and the 5- and 10-year OS rates of patients that did not receive consolidation treatment was 20%.

Conclusions

Survival was significantly worse in the group that did not receive consolidation treatment. Furthermore, our results suggested that carboplatin could be used effectively as an alternative to actinomycin-D in ES consolidation treatment.

Identifying barriers to treatment of childhood rhabdomyosarcoma in resource-limited settings: A literature review

We performed a literature review to examine barriers for rhabdomyosarcoma treatment in low-resource settings, and identified 29 articles from 14 middle-income countries, with none from low-income countries. Notable findings included inconsistent use of local control modalities, lack of diagnostics in some settings, and high rate of abandonment specifically in low middle-income countries. Reported limitations included lack of surgical expertise and/or radiation therapy, advanced stage of disease, and absence of health insurance. Although very poor outcomes were prevalent in several settings, good outcomes were achievable in others when multidisciplinary therapy and financial coverage of medical care were made available.

Biological indicators of chemoresistance: an ex vivo analysis of γH2AX and p53 expression in feline injection-site sarcomas

Background

The response of soft tissue sarcomas to cytotoxic chemotherapy is inconsistent. Biomarkers of chemoresistance or chemosensitivity are needed in order to identify appropriate patients for treatment. Given that many chemotherapeutics kill cells through direct DNA interactions, we hypothesized that upregulation of DNA damage response mechanisms would confer resistance to cytotoxic chemotherapy in sarcomas. To study this, we used spontaneously-occurring feline injection-site sarcomas (FISS).

Methods

γH2AX and p53 expression were determined in biopsy samples of FISS. γH2AX expression was determined via immunohistochemistry whereas p53 expression was determined via qRT-PCR. Cell lines derived from these sarcoma biopsies were then treated with carboplatin (N = 11) or doxorubicin (N = 5) and allowed to grow as colonies. Colony forming-ability of cells exposed to chemotherapy was compared to matched, untreated cells and expressed as percent survival relative to controls. ImageJ was used for quantification. A mixed model analysis was performed to determine if an association existed between relative survival of the treated cells and γH2AX or p53 expression in the original tumors. Cell lines were validated via vimentin expression or growth as subcutaneous sarcomas in nude mice.

Results

An association was detected between γH2AX expression and relative survival in cells exposed to carboplatin (P = 0.0250). In the 11 FISS tumors evaluated, γH2AX expression ranged from 2.2 to 18.8% (mean, 13.3%). Cells from tumors with γH2AX expression higher than the sample population mean had fourfold greater relative survival after carboplatin exposure than cells from tumors with γH2AX expression less than the mean. There was no association between relative survival after carboplatin exposure and p53 expression (P = 0.1608), and there was no association between relative survival after doxorubicin exposure and either γH2AX (P = 0.6124) or p53 (P = 0.8645) expression. Four cell lines were validated via growth as sarcomas in nude mice. Vimentin expression was confirmed in the other 7 cell lines.

Conclusions

γH2AX expression, but not wild type p53, may potentially serve as a biomarker of resistance to platinum therapeutics in soft tissue sarcomas. To further investigate this finding, prospective, in vivo studies are indicated in animal models.

Treatment Outcome and Predictors of Survival in Thai Adult Rhabdomyosarcoma Cases

BACKGROUND

Adult rhabdomyosarcoma (RMS) is a rare and aggressive disease with limited data compared with pediatric RMS. The goal of this study was to determine the treatment outcome and identify factors related to survival outcome in Thailand.

MATERIALS AND METHODS

Adult patients (≥15 years old) with the pathological diagnosis of RMS between 1985 and 2010 were reviewed. The data were retrospectively reviewed from the pathological results and medical records from Srinagarind Hospital, Khon Kaen University.

RESULTS

A total of 34 patients were identified in the study. The median age at diagnosis was 35.5 years and the most common primary sites were extremity and the head and neck region. The incidence of pleomorphic RMS increased with age and none was found in those aged younger than 20 years old. The median survival time was 9.33 months (95%CI: 5.6-13.1). The 1- and 5- year survival rates were 38.2% (22.3-54.0) and 20.6% (9.1-35.3). On multivariate analysis, age and size of tumor did not predict better outcome while chemotherapy and surgery were significantly associated with longer survival.

CONCLUSIONS

Outcome of adult RMS was poor. Surgery and chemotherapy are s trongly associated with better prognosis and multimodality treatment should be incorporated in the clinic.