906P - Prognostic impact and therapeutic implications of comprehensive genomic profiling (CGP) in non-metastatic salivary gland cancers (nmSGC)

Background

SGCs are a group of heterogenous malignances with guarded prognosis. At recurrence, CGP is recommended as up to 30% of patients (pts) harbor actionable alterations (AA). The REDESIGN study evaluated the prognostic impact and potential therapeutic implications of performing CGP in nmSGCs.

Methods

Multicenter retrospective cohort of nmSGCs pts treated with curative intent at 5 Spanish institutions between 2000 and 2020. Diagnostic/surgical tumor samples underwent CGP using Roche AVENIO Tumor Tissue CGP Kit detecting small variants in 324 genes, copy number alterations and fusions, as well as tumor mutational burden (TMB) using the FoundationOne® Analysis pipeline. Sequencing was performed on an Illumina NextSeq 550Dx platform: SNVs with depth ≥150x and variant allele frequency >3%, and CNAs >10 copies were included. CGP was correlated with prognostic variables and recurrence-free survival (RFS).

Results

Out of 142 nmSGC pts/samples, 105 met criteria for inclusion: adenoid cystic (AC) n=29; ductal (DC) n=29; mucoepidermoid (MEC) n=22; acinic cell n=24. Sixty-eight of 105 pts (65%) had informative CGP (CGP+) and 46 (44%) had at least one AA (AA+). Table summarizes AA+ by histologic subtype and ESMO ESCAT classification. Proportion of CGP+/AA+ differed by histologic subtype, being higher in AC and DC (72/41% and 93/83%, p

Conclusions

CGP+ in nmSGCs is associated with poor outcome and distant recurrence. The rates of AA+ provide an opportunity to evaluate matched therapies in the adjuvant setting.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Institut Català d'Oncologia (ICO).

Funding

Spanish Group for the Head and Neck Tumors (TTCC).

Disclosure

B. Cirauqui Cirauqui: Financial Interests, Personal, Other, Training grant: MSD, BMS, Merck; Financial Interests, Personal, Invited Speaker: BMS, Merck, MSD; Financial Interests, Personal, Advisory Board: BMS, MSD, Merck; Non-Financial Interests, Member, Board of directors: TTCC group; Non-Financial Interests, Member: GEICAM, SOLTI, SEOM. N. Baste Rotllan: Non-Financial Interests, Advisory Role: Eisai, MSD, Merck Serono, BioNTech, Roche, BMS, Exelixis. M. Oliva Bernal: Financial Interests, Personal, Invited Speaker: Merck, MSD, BMS; Financial Interests, Personal, Advisory Board: Merck, MSD; Financial Interests, Personal, Writing Engagement: MSD; Financial Interests, Personal, Invited Speaker, Teaching activities: MSD, Merck; Financial Interests, Personal, Other, IDMC: Transgene; Financial Interests, Personal and Institutional, Funding: Roche; Financial Interests, Institutional, Local PI: ALX Oncology, MSD, ISA Therapeutics BV, Roche, Ayala Therapeutics, Abbvie, Bayer, Boehringer Ingelheim, Merck, Debiopharm, Seagen, Gilead, Beigene, NYKODE; Financial Interests, Institutional, Funding: GSK; Non-Financial Interests, Institutional, Product Samples: Roche. All other authors have declared no conflicts of interest.