CORR® Tumor Board: Is Microscopic Vascular Invasion In Tumor Specimens Associated With Worse Prognosis In Patients With High-Grade Localized Osteosarcoma?

What are the surgical and research implications of this study? Megan E. Anderson MD Orthopaedic Oncology Surgeon Beth Israel Deaconess Medical Center and Boston Children’s Hospital Microscopic vascular invasion (MVI) is evidence of a tumor’s ability to invade the vascular system and extend more broadly into its primary location and metastasize to distant locations. All malignant tumors must have this capacity; it’s the definition of the term “cancerous”. We are in the infancy of developing the basic science for defining the cellular mechanisms that allow MVI in some tumors at a cellular level, and identifying it microscopically. Research has shown though, that if MVI is identified with the current techniques available for specific tumors, it is a sign of a worse prognosis [2, 5, 13]. Tsuda and colleagues [12] are the first to show this definitively in patients with localized osteosarcoma younger than 40 years of age. Now, we as scientists and clinicians need to stop this from happening in osteosarcoma as part of our approach to improve the survival of patients with that tumor [3]. To do this, we must first hone our tools to identify (and ideally) quantify MVI. Are there techniques we can use noninvasively with imaging modalities to determine this at diagnosis and after neoadjuvant chemotherapy prior to local control? Can pathologists agree on a uniform way of assessing this on resection specimens so that it can be part of every pathology report and also every trial for osteosarcoma? With current work in molecular genetics, we should be able to identify specific markers for MVI at diagnosis within the next decade or two [4] in the primary tumor and perhaps even in circulating tumor cells [10]. As Tsuda and colleagues [12] note, once MVI is identified and quantified, patients with osteosarcoma can then be properly stratified in trials to identify treatments that can better help these patients. If we see evidence of MVI with a radiographic imaging study at diagnosis and no improvement with restaging imaging done after two cycles of standard chemotherapy (high-dose methotrexate, doxorubicin, and cisplatin, [commonly referred to as MAP]) prior to local control surgery, then those patients may benefit from more-aggressive surgery with wider margins to decrease the risk of local relapse. Such patients (or those A note from the Editor-in-Chief: We are pleased to present the next installment of our CORR Tumor Board column, which provides multidisciplinary perspective on the themes raised in selected CORR tumor papers. In this column, we will discuss the implications of the highlighted article from the varied disciplines of the Tumor Board members: Orthopaedic surgery, pathology, and radiology. This month’s column features the study “Is Microscopic Vascular Invasion in Tumor Specimens Associated with Worse Prognosis in Patients with High-grade Localized Osteosarcoma? ” by Tsuda and colleagues available at: DOI: 10.1097/CORR.0000000000001079. The authors certify that neither they, nor any members of their immediate families, have any commercial associations (such as consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article. The opinions expressed are those of the writers, and do not reflect the opinion or policy of CORR or The Association of Bone and Joint Surgeons. Megan E. Anderson MD (✉), Beth Israel Deaconess Medical Center, 330 Brookline Ave., Boston, MA 02215 USA, Email: manders6@bidmc.harvard. edu