Abstract 3517
Background
The role of FDG-PET/CT in the FU of LA-HNSCC is unclear.
Methods
Scan reports of LA-HNSCC patients, having FU-FDG-PET/CT performed 6-18 months after ST/CRT were retrospectively analyzed. Equivocal reports were scored as positive. Excluded were patients with proven recurrence before FU-FDG-PET/CT. The reference standard was the occurrence of a second primary (SP) or a recurrence < 12 months after FU-FDG-PET/CT. Primary endpoints included sensitivity, specificity, positive (PPV) and negative predictive value (NPV) on a patient level.
Results
We identified 73 patients. Primary tumor site: oropharynx: n = 35; 7 larynx: n = 7; hypopharynx: n = 11; oral cavity: n = 4; paranasal sinus: n = 4; unknown: n = 5. Tumor stage (UICC 7): II (T2N0): n = 1; III: n = 9; IV: n = 63. T1: n = 8; T2: n = 20; T3: n = 16; T4: n = 24. N0: n = 10; N1: n = 7; N2: n = 53; N3: n = 2. Patients were treated by CRT (n = 29) or ST (n = 44). A prior FDG-PET/CT at 3 months after end of treatment (EOT) (EOT-FDG-PET/CT) had been performed in 69/73 (60 negative, 6 false and 3 true positive [resected lymph nodes]). FU-FDG-PET/CT in patients without EOT-FDG-PET/CT was true negative in 3 patients and true positive in 1. Median time between EOT and FU-FDG-PET/CT was 12 months (range 6-17). Median FU after FU-FDG-PET/CT was 48 months (range 2-130). Sensitivity, specificity, PPV and NPV were 83% (95% CI 52-98), 87% (95% CI 76-94), 56% (95% CI 31-78) and 96% (95% CI 87-100), respectively. Local recurrences, SP and distant metastases were detected in 5, 1, and 4 patients, respectively. One FU-FDG-PET/CT-detected local recurrence and 1 SP were treated with curative intent. All false-positive patients (n = 8) underwent biopsy (n = 3) or surgery (n = 5). 15 patients (21%) recurred > 12 months after FU-FDG-PET-CT. Median overall survival was 49 (95% CI 29 - 68) and 98 months (95% CI 86-111) in FU-FDG-PET/CT-positive and -negative patients, respectively (p = 0.000196).
Conclusions
FU-FDG-PET/CT in real-life has a high NPV and significant prognostic value. However, false-positive scans induce invasive procedures in a significant fraction of patients.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
2600 - Atezolizumab (atezo) vs chemotherapy (chemo) in patients (pts) with platinum-treated locally advanced or metastatic urothelial carcinoma (mUC): a long-term overall survival (OS) and safety update from the Phase III IMvigor211 study
Presenter: Michiel Van der Heijden
Session: Poster Display session 3
Resources:
Abstract
3598 - Three-Year Follow-Up From the Phase 3 KEYNOTE-045 Trial: Pembrolizumab (Pembro) Versus Investigator’s Choice (Paclitaxel, Docetaxel, or Vinflunine) in Recurrent, Advanced Urothelial Cancer (UC)
Presenter: Andrea Necchi
Session: Poster Display session 3
Resources:
Abstract
2382 - First Report of Efficacy and Safety From a Phase 2 Trial of Tislelizumab, an Anti-PD-1 Antibody, for the Treatment of PD-L1+ Locally Advanced or Metastatic Urothelial Carcinoma (UC) in Asian Patients
Presenter: Dingwei Ye
Session: Poster Display session 3
Resources:
Abstract
2388 - Quality of Life of Metastatic Urothelial Cancer (mUC) Patients Treated with Enfortumab Vedotin (EV) Following Platinum-Containing Chemotherapy and a Checkpoint Inhibitor (CPI): Data from EV-201 Cohort 1
Presenter: Bradley McGregor
Session: Poster Display session 3
Resources:
Abstract
3748 - Safety and efficacy of atezolizumab (atezo) in patients (pts) with autoimmune disease (AID): subgroup analysis of the SAUL study in locally advanced/metastatic urinary tract carcinoma
Presenter: Yohann Loriot
Session: Poster Display session 3
Resources:
Abstract
1126 - Validation of the VIO prognostic index in patients with metastatic urothelial carcinoma treated with immune-checkpoint inhibitors
Presenter: Rafael Morales Barrera
Session: Poster Display session 3
Resources:
Abstract
3693 - Pathologic outcomes after neoadjuvant chemotherapy for high-risk muscle invasive bladder cancer
Presenter: Justin Matulay
Session: Poster Display session 3
Resources:
Abstract
4840 - Analysis of response to prior therapies and therapies after treatment with erdafitinib in fibroblast growth factor receptor (FGFR)-positive patients (pts) with metastatic urothelial carcinoma (mUC)
Presenter: Arlene Siefker-Radtke
Session: Poster Display session 3
Resources:
Abstract
1221 - Clinical outcomes by sex with atezolizumab (atezo) monotherapy in patients (pts) with locally advanced/metastatic urothelial carcinoma (mUC)
Presenter: Jean Hoffman-censits
Session: Poster Display session 3
Resources:
Abstract
1715 - National Small Cell Bladder Cancer Audit: Results from 26 UK institutions
Presenter: Caroline Chau
Session: Poster Display session 3
Resources:
Abstract