Chemotherapy and targeted treatments of breast sarcoma by histologic subtype

ABSTRACT

Introduction: Breast sarcomas (BS) are uncommon and often present both diagnostic and therapeutic challenges. Historically, radical surgery has been the mainstay of treatment for localized breast sarcomas. On the other hand, in advanced disease, since they are a heterogeneous group of neoplasms consisting of several different subtypes including angiosarcoma, phyllodes tumor, and pleomorphic undifferentiated sarcoma, there is a lack of proven specific therapy. As a result, their treatment is based on the soft tissue sarcoma (STS) paradigm, whereas histotype-tailored approaches apply to specific subtypes like dermatofibrosarcoma protuberans. To date, advanced stages constitute an incurable form of disease and chemotherapy remains the cornerstone of treatment with the aim of palliation of symptoms and increase in survival.

Areas covered: In this manuscript, we review the clinicopathologic characteristics of the most common subtypes of BS, as well as the current treatment landscape of BS, with a particular focus on opportunities and challenges provided by new targeted molecules and immunotherapy.

Expert opinion: The treatment approach of advanced BS is based on the pathologic subtype. A true breakthrough has still to be obtained, as the development of new agents in BS suffers from the same weaknesses as in other STS.

KEYWORDS:

• Advanced
• angiosarcoma
• breast
• DFSP
• phyllodes
• Sarcoma
• treatment
• immunotherapy

Article highlights

• Breast sarcomas (BS) are rare heterogeneous tumors representing 5% of all sarcomas.

• Current therapeutic options are based on the experience from other STS.

• Angiosarcoma is a particularly aggressive form of BS, with diffuse local extension and a tendency for local recurrence. Therefore, a multi-modal treatment, including extensive surgery and adjuvant therapies, is proposed.

• Dermatofibrosarcoma protuberans (DFSP) is a low-grade sarcoma with low probability of metastases. Its treatment is primarily surgical. Imatinib has a place in the management of unresectable or metastatic disease.

• Phyllodes tumors represent another tumor type of the sarcoma spectrum and have heterogeneous behavior with most being benign but some displaying a borderline, or frank malignant behavior.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper received no funding.