Lymph Node Involvement and the Clinical Stage as Predictors of the Survival of Patients With Adenoid Cystic Carcinoma of the Head and Neck: A Systematic Review and Meta-Analysis

In the treatment of various patients, the presence of lymphovascular invasion is a prognostic determinant, often taken into account by surgeons and oncologists. The exact frequency and prognostic impacts of this microscopic event in adenoid cystic carcinoma (ACC) patients are, however, not clear. This systematic review and meta-analysis aimed to investigate the lymph node involvement and the clinical stage of cancer as predictors of ACC prognosis. A systematic search was conducted covering a number of databases, including PubMed, Science Direct, Google Scholar, Web of Science, and EBSCO. A total of three studies were included in this analysis, with 591 participants, 247 of whom were males. Lymph node involvement and clinical stage were demonstrated as significant bad prognosis factors among ACC patients (HR = 1.48, 95% CI, 1.00, 1.96; P<0.0001). We found that lymph node involvement and clinical stage of the cancer are both significant predictors of bad prognosis of ACC.