Risk of second primary cancer in patients with head and neck squamous cell carcinoma: a systemic review and...

Second primary cancer is a common event in patients with head and neck squamous cell carcinoma. However, the incidence and relevant factors vary by studies. We conducted a systematic review and meta-analysis of observational studies to estimate the incidence and relevant risk factors.

PubMed and Web of Science were searched for studies published between January 2000 and December 2020 that reported the incidence of SPC in HNSCC patients. Per 1000-person-year incidence and odds ratios were used to estimate the incidence and potential risk factors. Due to the high heterogeneity, random-effects models were used to estimate the incidence and 95% confidence interval.

Seven thousand seven hundred thirteen articles were identified from the databases, in which 60 studies were included in this meta-analysis. The pooled incidence of the total, synchronous, and metachronous SPC in patients with HNSCC were 29.116 per 1000-person-year, 6.960 per 1000-person-year, and 26.025 per 1000-person-year, respectively. The head and neck region was the most common area where SPC occurred, followed by the lung (7.472 per 1000-person-year) and upper digestive tract (2.696 per 1000-person-year). Smoking, alcohol consumption, betel quid chewing, primary cancer of T_1-2, and N₀ were risk factors, while HPV infection (OR 0.47, 95% CI 0.30-0.72) was the protective factor.

SPC is frequently observed in HNSCC patients and had great impact on the prognosis. The findings could promote a more individualized follow-up strategy for SPC in HNSCC patients.

This systemic review and meta-analysis provide sufficient evidence for the establishment of the follow-up strategy for head and neck squamous cancer patients.