CSPG4 expression in soft tissue sarcomas is associated with poor prognosis and low cytotoxic immune response.

BACKGROUND: Soft tissue sarcomas (STS) are heterogeneous and pro-metastatic tumors. Identification of accurate prognostic factors and novel therapeutic targets are crucial. CSPG4 is a cell surface proteoglycan with oncogenic functions. It recently emerged as a potential target for immunotherapy, including cell therapy based on CSPG4-specific chimeric antigen receptor (CAR)-redirected cytokine-induced killer lymphocytes (CSPG4-CAR.CIKs) in STS. However, expression of CSPG4 is poorly known in STS so far. METHODS: We analyzed CSPG4 gene expression in 1378 localized STS clinical samples, and searched for correlations with clinicopathological data, including disease-free survival (DFS), and with tumor immune features. RESULTS: CSPG4 expression was heterogeneous across samples. High expression was associated with younger patients' age, more frequent undifferentiated pleomorphic sarcoma and myxofibrosarcoma pathological subtypes, more frequent internal trunk tumor site, and more CINSARC high-risk samples. No correlation existed with pathological tumor size and grade, and tumor depth. Patients with high CSPG4 expression displayed 49% (95% CI 42-57) 5-year DFS versus 61% (95% CI 56-68) in patients with low expression (p = 3.17E-03), representing a 49% increased risk of event in the "CSPG4-high" group (HR = 1.49, 95% CI 1.14-1.94). This unfavorable prognostic value persisted in multivariate analysis, independently from other variables. There were significant differences in immune variables between "CSPG4-high" and "CSPG4-low" tumors. The "CSPG4-low" tumors displayed profiles suggesting higher anti-tumor cytotoxic immune response and higher potential vulnerability to immune checkpoint inhibitors (ICI). By contrast, the "CSPG4-high" tumors displayed profiles implying an immune-excluded tumor microenvironment, potentially induced by hypoxia, resulting from an immature chaotic microvasculature, and/or the presence of contractile myofibroblasts. CONCLUSIONS: Patients with "CSPG4-high" STS, theoretically candidate for CAR.CIKs, display shorter DFS and an immune environment unfavorable to vulnerability to CAR.CIKs, which could be improved by combining anti-angiogenic drugs able to normalize the tumor vasculature. By contrast, "CSPG4-low" STS are better candidates for immune therapy involving ICI.

Immunologic constant of rejection signature is prognostic in soft-tissue sarcoma and refines the CINSARC signature.

BACKGROUND: Soft-tissue sarcomas (STSs) are heterogeneous and aggressive tumors, with high metastatic risk. The immunologic constant of rejection (ICR) 20-gene signature is a signature of cytotoxic immune response. We hypothesized that ICR might improve the prognostic assessment of early-stage STS. METHODS: We retrospectively applied ICR to 1455 non-metastatic STS and searched for correlations between ICR classes and clinicopathological and biological variables, including metastasis-free survival (MFS). RESULTS: Thirty-four per cent of tumors were classified as ICR1, 27% ICR2, 24% ICR3, and 15% ICR4. These classes were associated with patients' age, pathological type, and tumor depth, and an enrichment from ICR1 to ICR4 of quantitative/qualitative scores of immune response. ICR1 class was associated with a 59% increased risk of metastatic relapse when compared with ICR2-4 class. In multivariate analysis, ICR classification remained associated with MFS, as well as pathological type and Complexity Index in Sarcomas (CINSARC) classification, suggesting independent prognostic value. A prognostic clinicogenomic model, including the three variables, was built in a learning set (n=339) and validated in an independent set (n=339), showing greater prognostic precision than each variable alone or in doublet. Finally, connectivity mapping analysis identified drug classes potentially able to reverse the expression profile of poor-prognosis tumors, such as chemotherapy and targeted therapies. CONCLUSION: ICR signature is independently associated with postoperative MFS in early-stage STS, independently from other prognostic features, including CINSARC. We built a robust prognostic clinicogenomic model integrating ICR, CINSARC, and pathological type, and suggested differential vulnerability of each prognostic group to different systemic therapies.

Successful Imatinib Treatment of an Abdominal Compartment Syndrome due to Huge Gastrointestinal Stromal Tumour.

Gastrointestinal stromal tumours (GISTs) are the most common digestive mesenchymal tumours, whose prognosis has been revolutionised by targeted therapies such as oral imatinib. Abdomen compartment syndrome (ACS) is associated with mortality superior to 50% in adults. ACS has never been reported to date in patients with GIST. Specific anticancer treatment in critically ill patients in intensive care unit (ICU) remains a matter of debate given the high mortality rate. Here, we report the case of a 58-year-old woman with ACS related to a 40-cm huge GIST and multi-organ failure requiring mechanical ventilation, vasopressive support and haemodialysis. She was treated in emergency with imatinib via the naso-gastric tube (day 1), then at day 3 by decompressive laparotomy and "open abdomen" without any tumour removal. Imaging after 11 days imatinib showed objective tumour response. Because of improvement of multi-organ dysfunctions, the laparotomy was closed at day 14, and the resuscitation procedures were progressively stopped. After discharge from hospital, she survived nearly two years. This is the first case of successful treatment of cancer-associated ACS by targeted therapy and decompressive laparotomy. Imatinib in critically ill patients with GIST may be successful even in presence of multi-organ failure.

Metastatic Intimal Sarcoma of the Pulmonary Artery Sensitive to Carboplatin-Vinorelbine Chemotherapy: Case Report and Literature Review.

Pulmonary artery intimal sarcoma (PAIS) is a very rare tumour with a very poor prognosis. In advanced stages, chemotherapy and radiotherapy are poorly efficient, and no standard chemotherapy guideline is currently available. Here, we report on a 37-year-old woman with PAIS initially treated with surgical resection who developed metastatic relapse refractory to anthracycline-based chemotherapy, then trabectedin, then pazopanib. The patient was then given carboplatin-vinorelbine chemotherapy. The treatment was well tolerated, and, rapidly, a CT scan showed an objective response that lasted 8 months despite the 4th therapeutic line. We review the literature and show that our case is the second one that provides evidence of the efficacy of platinum-vinorelbine regimens in this aggressive tumour.

Reversible rituximab-induced rectal Kaposi's sarcoma misdiagnosed as ulcerative colitis in a patient with HIV-negative follicular lymphoma.

BACKGROUND: Kaposi's sarcoma is a low-grade mesenchymal angioproliferative tumor, most commonly observed in immunocompromised individuals, such as HIV-infected patients. Iatrogenic Kaposi's sarcoma occurs in patients undergoing immunosuppressive therapies. Rituximab is a chimeric monoclonal antibody targeted against the pan B cell marker CD20. Because of its immunosuppressive effects through reduction of mature B-cells, it may exacerbate Kaposi's sarcoma in HIV-positive patients. Rituximab-related Kaposi's sarcomas have been previously reported in only two HIV-negative patients and were treated surgically. CASE PRESENTATION: Here, we report on a Kaposi's sarcoma that developed under rituximab treatment in a HIV-negative 55-year-old patient treated for follicular lymphoma. The lesion developed during the maintenance rituximab therapy at the rectal level with an aspect of apparent ulcerative colitis, without any cutaneous lesion. The premature stop of rituximab led to the complete regression of Kaposi's sarcoma, without any additional specific treatment. CONCLUSIONS: To our knowledge, this is the third case of Kaposi's sarcoma diagnosed under rituximab in a HIV-negative patient, the first one at the rectal level and the first one that completely regresses after stop of rituximab. This case raises awareness of iatrogenic Kaposi's sarcoma in HIV-negative patients treated with rituximab, and further highlights the importance of immunosuppression in the pathophysiology of disease.