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
2115 - Preclinical in vivo screening to predict responder patients depend on EGFR status
Presenter: Yejin Kim
Session: Poster Display session 3
Resources:
Abstract
3349 - Interplay between miR-17-5p and MALAT-1 Shapes The Cytokine Storm in Triple Negative Breast Cancer (TNBC) Tumor Microenvironment
Presenter: Raghda Soliman
Session: Poster Display session 3
Resources:
Abstract
4014 - Clinical verification on the relationship between lipid metabolism and the immune microenvironment of breast cancer
Presenter: Wataru Goto
Session: Poster Display session 3
Resources:
Abstract
4158 - The clinical and transcriptional signatures of human CD204 reveal an applicable marker for tumor associated macrophage in breast cancer
Presenter: Yunjie He
Session: Poster Display session 3
Resources:
Abstract
5392 - Activated effector T cells co-expressing multiple inhibitory receptors (IRs) are enriched in the tumor immune microenvironment in high grade serous ovarian cancer (HGSOC)
Presenter: Alice Bergamini
Session: Poster Display session 3
Resources:
Abstract
2617 - Oncolytic reovirus as a new anti-tumor strategy in castration resistant prostate cancer
Presenter: Yunlim Kim
Session: Poster Display session 3
Resources:
Abstract
2995 - Dysregulation of helper T lymphocytes in esophageal squamous cell carcinoma (ESCC) patients is highly associated with aberrant production of miR-21
Presenter: Ali Memarian
Session: Poster Display session 3
Resources:
Abstract
3597 - Myeloid derived suppressor cells but not regulatory T cells are associated with adaptive immunity and clinical outcomes in anal squamous cell carcinoma
Presenter: Christophe Borg
Session: Poster Display session 3
Resources:
Abstract
3430 - Evaluation of immune responses among responders (R) and non-responders (non-R) in a humanized mouse model with colorectal cancer (CRC) xenografts treated with combination immunotherapy
Presenter: Juan Marín Jiménez
Session: Poster Display session 3
Resources:
Abstract
1995 - ¬¬Advanced melanoma patients with high CD16+ macrophages have better response and survival to anti-PD-1 based immunotherapy
Presenter: Hansol Lee
Session: Poster Display session 3
Resources:
Abstract