Histopathologic review of pineal parenchymal tumors identifies novel morphologic subtypes and prognostic factors for outcome

Authors

David R. Raleigh, University of California, San Francisco
David A. Solomon, University of California, San Francisco
Shane A. Lloyd, University of California, San Francisco
Ann Lazar, University of California, San Francisco
Michael A. Garcia, University of California, San Francisco
Penny K. Sneed, University of California, San Francisco
Jennifer L. Clarke, University of California, San Francisco
Michael W. McDermott, University of California, San Francisco
Mitchel S. Berger, University of California, San Francisco
Tarik Tihan, University of California, San Francisco
Daphne A. Haas-Kogan, University of California, San Francisco

Document Type

Article

Abstract

Background. Pineal parenchymal tumors (PPTs) are rare neoplasms of the central nervous system, and data concerning clinical outcomes are limited. The purpose of this study was to define the clinical behavior of PPT according to current histopathologic criteria and identify prognostic factors to guide therapeutic decisions. Methods. Seventy-five patients treated for PPT at a single institution between 1992 and 2015 were retrospectively identified. Forty-five resection specimens were available and re-reviewed. Freedom from progression (FFP) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using log-rank tests. Results. Median follow-up was 4.1 years. All patients initially underwent surgery; 78% of patients with PPT of intermediate differentiation (PPTID) and all patients with pineoblastoma received adjuvant therapy. Pathologic re-review refined classification in 27% of cases, with the majority of these being adult patients with pineal tumors originally classified as pineoblastomas that more accurately resembled PPTID based on the 2007 WHO classification. Classification. Our histologic review also identified that PPTIDs can be classified into small-cell and large-cell morphologic subtypes, which have distinct clinical outcomes. Tumor grade, extent of resection, and neuraxis spread were prognostic for FFP PPTID subtype, extent of resection, and neuraxis spread were prognostic for OS. Genetic analysis of a pineoblastoma case identified somatic mutations of DICER1, ARID1A, and KDM5C genes. Conclusions. PPTIDs can be classified into 1 of 2 novel morphologic subtypes that are associated with distinct clinical outcomes. Tumor grade, neuraxis spread, and extent of resection also influence outcome for patients with PPT.

Publication Date

1-1-2017

Publication Title

Neuro-Oncology

ISSN

15228517

E-ISSN

15235866

Volume

19

Issue

1

First Page

78

Last Page

88

PubMed ID

27282397

Digital Object Identifier (DOI)

10.1093/neuonc/now105

Recommended Citation

Raleigh, David R.; Solomon, David A.; Lloyd, Shane A.; Lazar, Ann; Garcia, Michael A.; Sneed, Penny K.; Clarke, Jennifer L.; McDermott, Michael W.; Berger, Mitchel S.; Tihan, Tarik; and Haas-Kogan, Daphne A., "Histopathologic review of pineal parenchymal tumors identifies novel morphologic subtypes and prognostic factors for outcome" (2017). Radiation Oncology. 24.
https://scholar.barrowneuro.org/radiation-oncology/24