Dramatic Response of a PD-L1-Positive Advanced Angiosarcoma of the Scalp to Pembrolizumab

Mapping the potential for anti-PD-1 therapy in advanced rare skin carcinomas

This review, focusing on cutaneous adnexal carcinomas, extramammary Paget disease (EMPD), cutaneous angiosarcomas (cAS) and Kaposi sarcoma (KS), summarizes their local recurrence and metastasis rates, tumor mutation burden (TMB), PD-L1 expression, and off-label treatment with systemic anti-PD-1 agents. PD-L1 expression and tumor mutation burden (TMB) were highly variable in adnexal carcinomas (also depending on the histological subtype), cAS and KS tumors, and some responses were noted even in lack of PD-L1 expression or in low-TMB tumors. There were encouraging best overall responses in patients with advanced rare skin carcinomas treated with anti-PD-1 agents in the literature, mostly after failure of other systemic treatments. We identified a total of 3 patients with sebaceous carcinoma (2 with complete response [CR], 1 with partial response [PR]), 5 with porocarcinoma (3 CR, 1 PR, 1 progression of disease [PD]), 2 with spiradenocarcinoma (1 PR, 1 PD), 1 with trichilemmal carcinoma with PR, 9 with EMPD (1 CR, 5 PR, 3 PD), 32 with cAS (5 CR, 18 PR, 9 PD), and 92 with KS (5 CR, 53 PR, 23 SD, 11 PD). However, a large variety of anti-PD-1 agents were used, in monotherapy or in combination with other systemic therapy, in a relatively small number of patients, limiting interpretations on their individual efficacy. The development of clinical guidelines on rare skin carcinomas may provide standardized guidance to physicians towards best care.

Conference on challenges in sarcoma (CCS) 2024: Expert opinions on non-evidence-based management aspects

BACKGROUND

Soft tissue sarcomas (STS) and other mesenchymal tumours belong to rare, heterogeneous neoplasms with over 150 subtypes that pose significant challenges in diagnosis and clinical decision making. While guidelines address evidence-based diagnostic and therapeutic procedures, clinical situations and scenarios without evidence remain controversial in daily practice. The 2024 Conference on Challenges in Sarcoma (CCS2024) aimed to narrow these gaps with the support of an international and multidisciplinary panel of sarcoma experts.

METHODS

A Delphi process identified 200 controversial questions across eight prioritised clinical scenarios, including tenosynovial giant cell tumour, synovial sarcoma of the extremities, retroperitoneal sarcomas, angiosarcoma, phyllodes tumour, malignant peripheral nerve sheath tumour, uterine leiomyosarcoma, and atypical lipomatous tumour.

RESULTS

Sixty-four experts discussed 141 controversies during the conference and reached strong consensus (> 90 %) on 24 and consensus (> 75 %) on 45 key diagnostic and therapeutic issues, while unresolved controversies emphasized the need for further research.

CONCLUSIONS

CCS2024 provides a framework for clinical decision making and underscores the importance of consensus-driven approaches in the treatment of rare and complex malignancies.

Primary vascular tumors of bone: A comprehensive literature review on classification, diagnosis and treatment

Primary vascular tumors of bone are a heterogeneous group of neoplasms, ranging from benign hemangiomas to frankly malignant epithelioid hemangioendotheliomas and angiosarcomas. Over the years, their classification has been a matter of discussion, due to morphologic similarities and uncertainty regarding biologic behavior. Over the past decade, with the development of next-generation sequencing, there has been a significant improvement in the molecular characterization of these lesions. The integration of their morphologic, immunohistochemical and molecular features has led to a better stratification, with important prognostic and therapeutic implications. Nevertheless, primary vascular bone tumors still represent a challenge for medical oncologists. Given their rarity and heterogeneity, in the last few years, there has been no significant progress in medical treatment options, so further research is needed. Here we present a review of the current knowledge regarding primary vascular tumors of the bone, correlating clinicopathologic features with tumor behavior and therapeutic approaches.

Current understanding of angiosarcoma: disease biology and evolving treatment

Angiosarcoma is a very rare soft tissue sarcoma that originates from endothelial cells and typically has a poor prognosis. It is most commonly found in elderly white men and can occur anywhere in the body, particularly in the head, neck, and scalp. Patients who have undergone previous radiation treatment or who have chronic lymphedema also face an elevated risk of this condition. Various genetic changes are suspected to contribute to the development of angiosarcoma, and these changes have been identified as potential targets for treatment. For localized disease, wide surgical resection is often the prudent course of action. A multidisciplinary approach, which may include surgery, radiotherapy, systemic chemotherapy, or immunotherapy, is typically the most effective way to achieve favorable outcomes. In this review, we discuss the general understanding of angiosarcoma and its management, with a particular focus on the current evolving treatments for the disease.

Cutaneous angiosarcoma: A review of current evidence for treatment with checkpoint inhibitors

Cutaneous angiosarcoma (cAS) is a rare and aggressive subtype of soft tissue sarcoma with poor prognosis and suboptimal treatment options. Clinical presentation is variable, but cAS often arises from the head and neck. The most widely accepted current approach, surgical excision with adjuvant radiotherapy, is associated with high recurrence rates and can leave patients with profound disfigurement. Chemotherapy and targeted therapy alternatives have had limited success. Thus, there is a significant unmet need to address the absence of durable treatments for advanced and metastatic cAS. Like melanoma and cutaneous squamous cell carcinoma, tumor types with known response to immunotherapy, cAS harbors immune biomarkers, such as tumor mutational burden high (TMB-H), PD-L1 positivity, ultraviolet signature expression, and tertiary lymphoid structures. While data on the use and efficacy of immunotherapy in cAS is limited, the biomarkers suggest a promising advancement in future treatment options. This review aims to summarize and discuss current data from case reports, case series, retrospective studies and clinical trials regarding immunotherapy treatment and outcomes for cAS.

Immunological and Genomic Analysis Reveals Clinically Relevant Distinctions between Angiosarcoma Subgroups

Angiosarcomas (AS) are extremely rare and aggressive vascular malignancies subdivided in de novo primary AS (pAS) and secondary AS (sAS). We hypothesize that the combination of immunological and genomic profiles significantly differs between primary and secondary AS, with potential impact on treatment strategies and a role for immunotherapy. Tumor-infiltrating lymphocytes were analyzed using multiplex immunohistochemistry from 79 pAS and 178 sAS. Median cell density was significantly higher in sAS for CD3+ T-cells (p < 0.001), CD8+ cytotoxic T-cells (p = 0.033), CD4+ T-helper cells (p < 0.001) and FoxP3+ T-regulatory cells (p < 0.001). CD20+ B-cell density was comparable (p = 0.417). Comprehensive genomic profiling was performed in 25 pAS and 25 sAS. A (likely) pathogenic mutation was detected in 80% of pAS vs. 88% of sAS (p = 0.702). Amplifications were found in 15% of pAS vs. 84% of sAS (p < 0.001). DNA damage response (DDR) pathway mutations (p = 0.021) and MYC amplifications (p < 0.001) were predominantly seen in sAS. In conclusion we observed a clear and clinical relevant distinction in immune infiltration and genomic profiles between pAS and sAS. The T-cell infiltrated tumor microenvironment and frequent DDR gene mutations, especially in sAS, warrant clinical trials with immunotherapy.

Clinical, genomic, and transcriptomic correlates of response to immune checkpoint blockade-based therapy in a cohort of patients with angiosarcoma treated at a single center

Background

Angiosarcoma is a histologically and molecularly heterogeneous vascular neoplasm with aggressive clinical behavior. Emerging data suggests that immune checkpoint blockade (ICB) is efficacious against some angiosarcomas, particularly cutaneous angiosarcoma of the head and neck (CHN).

Methods

Patients with histologically confirmed angiosarcoma treated with ICB-based therapy at a comprehensive cancer center were retrospectively identified. Clinical characteristics and the results of targeted exome sequencing, transcriptome sequencing, and immunohistochemistry analyses were examined for correlation with clinical benefit. Durable clinical benefit was defined as a progression-free survival (PFS) of ≥16 weeks.

Results

For the 35 patients included in the analyses, median PFS and median overall survival (OS) from the time of first ICB-based treatment were 11.9 (95% CI 7.4 to 31.9) and 42.5 (95% CI 19.6 to 114.2) weeks, respectively. Thirteen patients (37%) had PFS ≥16 weeks. Clinical factors associated with longer PFS and longer OS in multivariate analyses were ICB plus other therapy regimens, CHN disease, and white race. Three of 10 patients with CHN angiosarcoma evaluable for tumor mutational burden (TMB) had a TMB ≥10. Five of six patients with CHN angiosarcoma evaluable for mutational signature analysis had a dominant mutational signature associated with ultraviolet (UV) light. No individual gene or genomic pathway was significantly associated with PFS or OS; neither were TMB or UV signature status. Analyses of whole transcriptomes from nine patient tumor samples found upregulation of angiogenesis, inflammatory response, and KRAS signaling pathways, among others, in patients with PFS ≥16 weeks, as well as higher levels of cytotoxic T cells, dendritic cells, and natural killer cells. Patients with PFS <16 weeks had higher numbers of cancer-associated fibroblasts. Immunohistochemistry findings for 12 patients with baseline samples available suggest that neither PD-L1 expression nor presence of tumor-infiltrating lymphocytes at baseline appears necessary for a response to ICB-based therapy.

Conclusions

ICB-based therapy benefits only a subset of angiosarcoma patients. Patients with CHN angiosarcoma are more likely to have PFS ≥16 weeks, a dominant UV mutational signature, and higher TMB than angiosarcomas arising from other primary sites. However, clinical benefit was seen in other angiosarcomas also and was not restricted to tumors with a high TMB, a dominant UV signature, PD-L1 expression, or presence of tumor infiltrating lymphocytes at baseline.

[Medicinal treatment of retroperitoneal soft tissue sarcomas]

Retroperitoneal soft tissue sarcomas represent extreme challenges for interdisciplinary treatment teams. The sarcoma-specific experience of surgeons has the greatest impact on the survival of patients; however, too many patients still die despite optimal local treatment. The role of chemotherapy is undisputed only for patients with highly malignant bone sarcomas or rhabdomyosarcomas. For soft tissue sarcomas in adult patients, especially liposarcomas and leiomyosarcomas, the evidence situation is very unsatisfactory. This overview article discusses the complex data situation and controversial aspects that are relevant for current treatment decisions in interdisciplinary treatment teams.

Localized Angiosarcoma, Not One Disease: A Retrospective Single-Center Study on Prognosis Depending on the Primary Site and Etiology

BACKGROUND

Angiosarcomas are rare and heterogeneous tumors with poor prognosis. The clinical subtypes are classified depending on the primary site and etiology.

METHODS

We conducted a retrospective, monocentric study of 136 patients with localized AS between May 1985 and November 2018. Overall survival (OS), local recurrence-free survival (LRFS), and metastasis-free survival (MFS) were estimated using the Kaplan-Meier method. To identify prognostic factors, univariate and multivariate analyses were performed based on Cox regressions.

RESULTS

The median age was 67 years (19-72.8 years). Primary sites were cutaneous (27.2%), breast (38.2%), and deep soft tissue (34.6%). The majority was primary angiosarcomas (55.9%) followed by postradiation (40.4%) and chronic lymphedema angiosarcomas (2.9%). Prognosis significantly differed depending on the primary site and etiology. Shortest median OS and MFS were observed in deep soft tissue angiosarcomas, whereas cutaneous angiosarcomas, angiosarcomas of the breast, and radiation-associated angiosarcomas displayed worse median LRFS. Univariate analyses showed better OS for tumor size <10 cm (p = 0.009), negative surgical margins (p = 0.021), and negative lymph node status (p = 0.007). LRFS and MFS were longer for tumor size <10 cm (p = 0.012 and p = 0.013). In multivariate analyses, age <70 years was the only independent positive prognostic factor for OS in all subgroups. For LRFS, secondary AS of the breast was a negative prognostic factor (HR: 2.35; p = 0.035).

CONCLUSIONS

Different behaviors and prognoses depending on the primary site and etiology should be considered for the treatment of this heterogeneous disease. In cutaneous angiosarcomas of the head/neck and postradiation angiosarcomas of the breast, local recurrence seems to have a crucial impact on OS. Therefore, improved local therapies and local tumor staging may have to be implemented. However, in deep soft tissue angiosarcomas, distant recurrence seems to have a major influence on prognosis, which indicates a benefit of additional perioperative chemotherapy.

[Cutaneous angiosarcoma clinically presenting as Quincke's edema]

We report a case of a 75-year-old man with facial edema that also affected the periorbital area who was admitted to the hospital with the suspected diagnosis of Quincke's edema. The diagnosis of cutaneous angiosarcoma was made by microscopic examination and immunohistochemical staining. Chemotherapy was initially initiated because the angiosarcoma was unresectable and the radiation situation was difficult. Therapy has to be switched to second and third line therapy due to disease progression. The case illustrates the complexity of diagnosis and therapy in patients with cutaneous angiosarcoma.

Angiosarcoma heterogeneity and potential therapeutic vulnerability to immune checkpoint blockade: insights from genomic sequencing

BACKGROUND

Angiosarcoma is an aggressive tumor. Recent case series describe exceptional responses to checkpoint blockade in this disease.

METHODS

Herein, we explored the genomic correlates of 48 angiosarcomas from the Angiosarcoma Project (12,499 variants analyzed in 6603 genes; whole-exome sequencing) versus 10,106 pan-cancer tumors in The Cancer Genome Atlas including 235 sarcomas but no angiosarcoma.

RESULTS

At the molecular level, angiosarcomas were heterogeneous. Those located in the face and scalp presented high tumor mutation burden, missense amino acid variations biased towards more hydrophobic (and therefore more immunogenic) peptides, and ultra-violet mutational signature.

CONCLUSIONS

Angiosarcoma molecular features are similar to those observed in melanoma and other skin tumors and may explain comparable immunotherapy sensitivity of these tumor types.

Angiosarcoma patients treated with immune checkpoint inhibitors: a case series of seven patients from a single institution

BACKGROUND

Angiosarcoma is an uncommon endothelial malignancy and a highly aggressive soft tissue sarcoma. Due to its infiltrative nature, successful management of localized angiosarcoma is often challenging. Systemic chemotherapy is used in the metastatic setting and occasionally in patients with high-risk localized disease in neoadjuvant or adjuvant settings. However, responses tend to be short-lived and most patients succumb to metastatic disease. Novel therapies are needed for patients with angiosarcomas.

METHODS

We performed a retrospective analysis of patients with locally advanced or metastatic angiosarcoma, who were treated with checkpoint inhibitors at our institution. We collected their clinical information and outcome measurements. In one patient with achieved complete response, we analyzed circulating and infiltrating T cells within peripheral blood and tumor tissue.

RESULTS

We have treated seven angiosarcoma (AS) patients with checkpoint inhibitors either in the context of clinical trials or off label [Pembrolizumab + Axitinib (NCT02636725; n = 1), AGEN1884, a CTLA-4 inhibitor (NCT02694822; n = 2), Pembrolizumab (n = 4)]. Five patients had cutaneous angiosarcoma, one primary breast angiosarcoma and one radiation-associated breast angiosarcoma. At 12 weeks, 5/7 patients (71%) had partial response of their lesions either on imaging and/or clinical exam and two (29%) had progressive disease. 6/7 patients are alive to date and, thus far, 3/7 patients (43%) have progressed (median 3.4 months)- one achieved partial response after pembrolizumab was switched to ongoing Nivolumab/Ipilimumab, one died of progressive disease at 31 weeks (primary breast angiosarcoma) and one was placed on pazopanib. One patient had a complete response (CR) following extended treatment with monotherapy AGEN1884. No patient experienced any ≥ grade 2 toxicities.

CONCLUSIONS

This case series underscores the value of targeted immunotherapy in treating angiosarcoma. It also identifies genetic heterogeneity of cutaneous angiosarcomas and discusses specific genetic findings that may explain reported benefits from immunotherapy.

[Systemic therapy of sarcomas : New biomarkers and therapeutic strategies]

Diagnostics and treatment of mesenchymal tumors (i.e. soft tissue sarcomas, gastrointestinal stromal tumors, and bone sarcomas) have changed dramatically in the past few years. Molecular and immunohistochemical biomarkers contribute significantly to improved diagnostics. They also play an increasing role in terms of clinical treatment decisions.Grading and tumor type-specific outcome data provide the basis for adjuvant chemotherapy of localized sarcomas. Recurrent gene fusions become more important as predictive biomarkers for targeted therapies in the context of systemic treatments. Immuno-oncology-based approaches are currently being studied in clinical trials, and the first responses of selected patients have been demonstrated. However, the role of predictive biomarkers in this field, such as PD-L1, still needs to be elucidated. Comprehensive genetic analyses of metastatic sarcomas will continue to identify additional therapeutic targets and the corresponding biomarkers.