Cervical lymph node metastasis in adenoid cystic carcinoma of oral cavity and oropharynx: A collective international review

Abstract

The purpose of this study was to establish general guidelines in the management of the N0 neck of oral cavity and oropharyngeal adenoid cystic carcinoma (AdCC) in order to improve the survival of these patients and/or reduce the risk of neck recurrences. The incidence of cervical node metastasis at diagnosis of head and neck AdCC is variable, and ranges between 3% and 16%. Metastasis to the cervical lymph nodes of intraoral and oropharyngeal AdCC varies from 2% to 43%, with the lower rates pertaining to palatal AdCC and the higher rates to base of the tongue. Neck node recurrence may happen after treatment in 0–14% of AdCC, is highly dependent on the extent of the treatment and is very rare in patients who have been treated with therapeutic or elective neck dissections, or elective neck irradiation. Lymph node involvement with or without extracapsular extension in AdCC has been shown in most reports to be independently associated with decreased overall and cause-specific survival, probably because lymph node involvement is a risk factor for subsequent distant metastasis. The overall rate of occult neck metastasis in patients with head and neck AdCC ranges from 15% to 44%, but occult neck metastasis from oral cavity and/or oropharynx seems to occur more frequently than from other locations such as the sinonasal tract and major salivary glands. Nevertheless, the benefit of elective neck dissection (END) in AdCC is not comparable to that of squamous cell carcinoma, because the main cause of failure is not related to neck or local recurrence, but rather, to distant failure. Therefore, END should be considered in patients with a cN0 neck with AdCC in some high risk oral and oropharyngeal locations when postoperative RT is not planned, or the rare AdCC-high grade transformation.

Predictors of Outcome in Adenoid Cystic Carcinoma of Salivary Glands

“…None of the oropharyngeal ACC was positive for p16 and/or high risk human papillomavirus. In our cohort, it appeared that intraoral/oropharyngeal ACCs were associated with higher risk (38%) of regional metastasis compared to those from other sites (14%), which was in agreement with results from previous studies (16, 32). …”

“…In the study herein, lymph node metastasis was found in a significant number of patients, being 15% in the entire cohort and 25% in patients who had lymph node sampling; this seems to be higher than the reported lymph metastasis rate in typical adenoid cystic carcinoma (1, 15, 16, 28, 32), and is likely to be related to selection bias in performing lymph node sampling and referral bias as the study cohort included patients from a tertiary cancer center. Among the 21 patients who harbored nodal metastasis, the majority (13/21, 62%) were patients with intraoral or oropharyngeal ACC.…”

Genetic Profiling in Heterogeneous High-Grade Adenoid Cystic Carcinoma Identifies NOTCH1 Inhibition as a Therapeutic Strategy

“…Adenoid cystic carcinoma with high-grade transformation is another subgroup of ACC although it is very rare. The striking clinical features of ACC-HGT was the high propensity for lymph node metastasis present, which was in 3 of the 5 cases and with shortened survival 38 . Investigations of the molecular alterations underlying this extremely aggressive behavior are minimal.…”

“…Patients diagnosed with ACC were reviewed from the archives of the Ninth People's Hospital affiliated to Shanghai Jiao Tong University during 2000-2019. A total of 36 high-grade ACC patients with available follow-up records were selected for this study, and the corresponding para n-embedded ACC specimens were obtained from the Department of Oral Pathology, the Ninth People's Hospital, following the approval of the University Institutional Ethics Committee according to histologic criteria 38,41 . All patients signed the informed consent.…”

Tumor‐derived exosomes enhance invasion and metastasis of salivary adenoid cystic carcinoma cells

“…Powerful local invasion, migration, and hematogenous metastasis lead to the difficulty in clinic treatment and prognosis. Therefore, the effects of various biological factors on the aggressive potentials of SACC and the molecular mechanism of SACC pathogenesis have been extensively studied . However, these processes are still poorly understood.…”