Detectable Post-operative Circulating Tumor Human Papillomavirus (HPV) DNA And Association with Recurrence in Patients with HPV-Associated Oropharyngeal Squamous Cell Carcinoma.
Int J Radiat Oncol Biol Phys 2022;
113:530-538. [PMID:
35157995 DOI:
10.1016/j.ijrobp.2022.02.012]
[Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 01/22/2022] [Accepted: 02/06/2022] [Indexed: 01/05/2023]
Abstract
PURPOSE
To determine the rate of detectability of ctHPVDNA after surgery but before adjuvant therapy in patients with HPV-associated oropharyngeal squamous cell carcinoma (HPV(+)OPSCC) and to investigate whether detectable ctHPVDNA at this time point may be associated with risk of recurrence.
METHODS AND MATERIALS
Prospectively collected samples from patients with OPSCC were examined in a blinded fashion using a multi-analyte PCR assay. 45 samples were collected from HPV(+)OPSCC patients pre-op (prior to any treatment), and 159 samples post-op (before or at the start of adjuvant RT). Samples were identified via the radiation oncology biobank or via participation in a clinical trial. RT consisted of 60 Gy +/- cisplatin or de-escalation (30 Gy to 36 Gy in 20 b.i.d. fractions + docetaxel). 32 patients had paired samples available pre and post-op for the primary analysis. Additional exploratory analyses including associations of patient and tumor characteristics with recurrence were assessed using Cox proportional hazards models for all 159 post-op samples.. Detectability of ctHPVDNA was compared across groups utilizing logistic regression. Estimates of recurrence free survival (RFS) were made using Kaplan-Meier (KM).
RESULTS
In a paired analysis of 32 pre and post-op timepoints, 94% of patients had detectable ctHPVDNA pre-op and 41% post-op. RFS at 18 months was 83% (95% CI: 47-95%) for patients with detectable post-op ctHPVDNA compared to 100% for patients with undetectable post-op ctHPVDNA (p=.094).In an exploratory analysis of non-paired post-op samples, ctHPVDNA was detectable in 26% (41 of 159) of patients (median of 22 days post-op). Age (1.06, p=0.025), LVSI (OR 3.17, p=0.011) and ENE (OR=5.67, p=0.001) were associated with detectable ctHPVDNA after surgery. Detectable post-op ctHPVDNA was significantly associated with RFS (p<0.001).
CONCLUSION
Amongst patients with detectable pre-op ctHPVDNA, a significant proportion have detectable post-op ctHPVDNA in paired post-op samples, collected prior to the initiation of adjuvant radiation therapy. Future prospective study is warranted to investigate the association of detectable post-op ctHPVDNA with recurrence, including in comparison to established clinical and pathologic risk factors.
Collapse