Abstract 4887
Background
Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor, comprising less than 1% of head and neck neoplasms. Adjuvant radiotherapy (aRT) is suggested for late-stage disease (stage III or IV); however, recent evidence suggests that it may be associated with improved survival even for early-stage disease. Moreover, the prognostic significance of tumor location on overall (OS) and ACC-specific (ACC-S) survival is unclear. We sought to address these knowledge gaps via analyses of the Surveillance, Epidemiology and End Results (SEER) database.
Methods
Intraoral minor (m) and major (M) ACCs from the SEER database (1973-2015) were selected for analysis. Information on age, sex, race, site, stage, treatment and survival was retrieved. The associations of tumor site and aRT with OS and ACC-S were estimated using hazard ratios (HR) and corresponding 95% confidence intervals (CI) obtained via Cox regression models adjusted for covariates as appropriate. Analyses were done using Stata 15.1 (StataCorp LP, College Station, TX).
Results
There were 635 minor and 1,064 major (parotid: n = 547, submandibular: n = 470, sublingual: n = 47) ACC cases included in the analyses. Late-stage patients (49% of total) were significantly more likely to have received aRT (76% vs. 66%; P < 0.01) compared to those with early-stage disease. Submandibular was the only tumour site that demonstrated statistically significant survival differences compared to the other sites; i.e., worse OS (HR = 1.4; 95% CI = 1.1-1.8) and ACC-S (HR = 1.7; 95% CI = 1.2-2.3) compared to minor ACCs. This difference was only evident for late-stage tumours: stage IV submandibular cases had worse OS (HR = 2.1; 95% CI = 1.5-2.8) and ACC-S (HR = 2.4; 95% CI = 1.7-3.4) compared to stage IV minor ACCs. Overall, aRT was associated with better OS (HR = 0.7; 95% CI = 0.6-0.9) and ACC-S (HR = 0.8; 95% CI = 0.6-1.1). This beneficial effect was more pronounced and statistically confirmed only in stage IV disease.
Conclusions
These results, based on SEER data, suggest that aRT is associated with favorable survival only in late-stage ACC and that, among these late-stage tumors, submandibular gland ACCs have substantially worse prognosis than other sites, irrespective of aRT.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Academy of Athens PhD Scholarship to Jason Tasoulas; UNC Lineberger Tier 3 Developmental Award funds and the University Cancer Research Fund to A.L. Amelio.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4758 - A Phase I Study of the CDK4/6 Inhibitor, Palbociclib in combination with Cetuximab and Intensity Modulated Radiation Therapy (IMRT) for Locally Advanced Squamous Cell Carcinoma of the Head and Neck (SCCHN); A Result of Dose Escalation Cohort
Presenter: Nuttapong Ngamphaiboon
Session: Poster Display session 3
Resources:
Abstract
2607 - Single cycle induction treatment with Cisplatin/Docetaxel plus Durvalumab/Tremelimumab in Stage III-IVB head and neck squamous cell cancer (CheckRad-CD8 trial)
Presenter: Markus Hecht
Session: Poster Display session 3
Resources:
Abstract
1388 - Radiotherapy plus cisplatin (CDDP) or cetuximab (C225) in human papilloma-virus (HPV)-associated oropharyngeal cancer (OPC)? A dillema finally resolved. An updated meta-analysis.
Presenter: Petar Suton
Session: Poster Display session 3
Resources:
Abstract
1478 - Treatment outcomes of head and neck cancer patients 70 years and older receiving different chemo-radiation combinations.
Presenter: Majd Issa
Session: Poster Display session 3
Resources:
Abstract
3985 - Brachytherapy and non-cancer mortality in patients with oral cavity and oropharynx SCCs
Presenter: Jovian Yu
Session: Poster Display session 3
Resources:
Abstract
4036 - Final results of a phase II study of induction chemotherapy (CT) with paclitaxel (PTX) and panitumumab (P) followed by radiotherapy (RT) and P in patients (pts) with locally advanced head and neck cancer (LAHNC) no candidates to platinum: study PANTERA
Presenter: Javier Martinez Trufero
Session: Poster Display session 3
Resources:
Abstract
4779 - Window of Opportunity for Durvalumab (MEDI4736) plus Metformin Trial in Squamous Cell Carcinoma of the Head and Neck (SCCHN): interim safety analysis
Presenter: Tony Richa
Session: Poster Display session 3
Resources:
Abstract
2757 - Severe Oral Mucositis (SOM) Mitigation by Genetically Modified Lactococcus Lactis Bacteria (LLB) Producing Human Trefoil Factor 1 (hTFF1; AG013) in Patients Being Treated With Concomitant Chemoradiation (CRT) for Oral and Oropharyngeal Cancers (OCOPC)
Presenter: Suraj Singh
Session: Poster Display session 3
Resources:
Abstract
5559 - Transcriptome signatures of treatment responses in a preoperative window of opportunity trial of nivolumab and tadalafil in resectable squamous cell carcinoma of the head and neck
Presenter: Sanket Shukla
Session: Poster Display session 3
Resources:
Abstract
3263 - Risk and Impact of Renal Impairment of Locally Advanced Head and Neck Squamous Cell Carcinoma Patients Who Received Chemoradiotherapy with Cisplatin
Presenter: Thana Patimarattananan
Session: Poster Display session 3
Resources:
Abstract