Primary Adult Retroperitoneal Sarcoma: A Comprehensive Genomic Profiling Study

  • Andrea Necchi
  • Giuseppe Basile
  • Filippo Pederzoli
  • Marco Bandini
  • Petros Grivas
  • Gennady Bratslavsky
  • Philippe E. Spiess
  • J. Keith Killian
  • Douglas I. Lin
  • Erik Williams
  • Shakti Ramkissoon
  • Eric A. Severson
  • Brian M. Alexander
  • Jeffrey Venstrom
  • Prasanth Reddy
  • Kimberley McGregor
  • Julia A. Elvin
  • Alexa B. Schrock
  • Dean V. Pavlick
  • Dexter X. Jin
  • Sally E. Trabucco
  • Natalie Danzinger
  • Jeffrey S. Ross
Keywords: Retroperitoneal sarcoma, comprehensive genomic profiling, targeted therapy


Background Adult primary retroperitoneal sarcomas (RPSs) are a group of heterogeneous tumors with different
histological subtypes. Comprehensive genomic profiling (CGP) analyses have recently provided significant insights
into the biology of sarcomas by identifying genomic alterations (GAs) which could benefit from targeted therapies.
Methods RPS were evaluated by CGP using next-generation sequencing of up to 406 cancer-related genes. Tumor
mutational burden (TMB) was determined on 0.83 to 1.14 mut/Mb of sequenced DNA. Finally, PD-L1 expression was
Results Overall, 296 cases of primary RPS were analyzed. Liposarcoma (LPS) subtype had more GA/tumor than
leiomyosarcoma (LMS) subtypes, with follicular dendritic cell sarcomas harboring the highest and synovial sarcomas
the lowest. TP53 and Rb1 alterations were the highest in LMS, and CDK4/6 and MDM2 in LPS. However, both the
TMB and targetable GA rates were low across subtypes. PD-L1 immunostaining was low positive in 21% and high
positive in 5% of patients, respectively.
Conclusions CGP analysis revealed that potentially actionable genomic targets were rare in our cohort of RPS.
Moreover, RPSs seem less likely to respond to immune checkpoint inhibitors based on putative biomarkers status.
Nevertheless, genomic stratification according to histological subtypes led to description of GAs that can inform
future clinical trials design.

Author Biographies

Dr Necchi


Dr Basile





Dr Pederzoli



Dr Grivas




Dr Bratslavsky


Dr Spiess




Dr Killian


Dr Lin



How to Cite
Necchi, A., Basile, G., Pederzoli, F., Bandini, M., Grivas, P., Bratslavsky, G., Spiess, P. E., Killian, J. K., Lin, D. I., Williams, E., Ramkissoon , S., Severson, E. A., Alexander, B. M., Venstrom, J., Reddy, P., McGregor, K., Elvin, J. A., Schrock, A. B., Pavlick, D. V., Jin, D. X., Trabucco, S. E., Danzinger, N., & Ross, J. S. (2021). Primary Adult Retroperitoneal Sarcoma: A Comprehensive Genomic Profiling Study. Société Internationale d’Urologie Journal, 2(4).
Original Research