Multimodality Treatment of Skull Base Chondrosarcomas: The Role of Histology Specific Treatment Protocols

Shaan M Raza; Paul W Gidley; Jeanne M Meis; David R Grosshans; Diana Bell; Franco DeMonte

doi:10.1093/neuros/nyx042

Multimodality Treatment of Skull Base Chondrosarcomas: The Role of Histology Specific Treatment Protocols

Neurosurgery. 2017 Sep 1;81(3):520-530. doi: 10.1093/neuros/nyx042.

Authors

Shaan M Raza¹, Paul W Gidley², Jeanne M Meis³, David R Grosshans⁴, Diana Bell³, Franco DeMonte¹

Affiliations

¹ Department of Neurosurgery, The University of Texas M.D. Anderson Cancer Center, Houston, Texas.
² Department of Head and Neck Surgery, The University of Texas M.D. Anderson Cancer Center, Houston, Texas.
³ Department of Pathology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas.
⁴ Department of Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas.

PMID: 28368506
DOI: 10.1093/neuros/nyx042

Abstract

Background: Limited data exist to guide the multimodality management of chondrosarcomas (CSAs) arising in the skull base.

Objective: To determine the impact of histological subtype/grade on progression-free survival (PFS) and the indications for surgery, radiation, and chemotherapy based on histology.

Methods: A retrospective review was performed of 37 patients (conventional type: 81%, mesenchymal: 16.2%, dedifferentiated: 2.7%) treated at The University of Texas M.D. Anderson Cancer Center. Of the conventional subtype, 23% were grade 1, 63% were grade 2, and 14% were grade 3. In addition to surgery, mesenchymal/dedifferentiated CSAs (18% of the cohort) underwent neoadjuvant chemotherapy and 48.6% of the overall cohort received adjuvant radiotherapy. Histological grade/subtype and treatment factors were assessed for impact on median PFS (primary outcome).

Results: Conventional subtype vs mesenchymal/dedifferentiated was positively associated with median PFS (166 vs 24 months, P < .05). Increasing conventional grade inversely correlated with median PFS ( P < .05). Gross total resection positively impacted PFS in conventional CSAs (111.8 vs 42.9 months, P = .201) and mesenchymal/dedifferentiated CSAs (58.2 vs 1.0 month, P < .05). Adjuvant radiotherapy significantly impacted PFS in conventional grades 2 and 3 (182 vs 79 months, P < .05) and a positive trend with mesenchymal/dedifferentiated CSAs (43.5 vs 22.0 months). Chemotherapy improved PFS for mesenchymal/dedifferentiated CSAs (50 vs 9 months, P = .089).

Conclusion: There is a potential need for histological subtype/grade specific treatment protocols. For conventional CSAs, surgery alone provides optimal results grade 1 CSAs, while resection with adjuvant radiotherapy yields the best outcome for grade 2 and 3 CSAs. Improvements in PFS seen with neoadjuvant therapy in mesenchymal/dedifferentiated CSAs indicate a potential role for systemic therapies. Larger studies are necessary to confirm the proposed treatment protocols.

Keywords: Chemotherapy; Chondrosarcoma; Malignancy; Oncology; Radiation Therapy; Sarcoma; Skull Base; Surgery.

MeSH terms

Chondrosarcoma* / epidemiology
Chondrosarcoma* / pathology
Chondrosarcoma* / therapy
Combined Modality Therapy / methods
Combined Modality Therapy / statistics & numerical data
Disease-Free Survival
Humans
Retrospective Studies
Skull Base Neoplasms* / epidemiology
Skull Base Neoplasms* / pathology
Skull Base Neoplasms* / therapy