Incidence of second primary malignancies in patients with treated head and neck cancer: a comprehensive review of literature

Abstract

Background:

Increased incidence of a second primary aero-digestive malignancy after an index head and neck cancer (HNC) is well-documented. Furthermore, a clear set of surveillance strategies for second primary aero-digestive cancers in these patients exists.

Methods:

The goal of this article is to review the published literature on risk of second primary malignancies (SPMs) (including aero-digestive malignancies) after a treated index HNC as well as its associated predictors, prognosis and surveillance. Most relevant publications were identified through searching the PubMed database for articles published up to July 2012; epidemiologic evidence was synthesized and thoroughly analyzed.

Findings:

Data from randomized controlled trials, meta-analyses, population-based and cohort group studies, prior reviews, and case reports indicate an increased incidence of various SPMs after occurrence of a HNC. These cancers are not limited to upper aero-digestive sites. Common risk factors including environmental, genetic and immune factors may explain the increased incidence of second cancers in this patient population. In addition, site of the index HNC may predict the site of a future SPM.

Conclusions:

As a general rule, oral cavity and oropharyngeal squamous cell cancers are associated more with head and neck region SPM, while laryngeal and hypopharyngeal cancers – with that of the lung. As these cancers confer dismal prognosis and shorter survival in patients with HNCs, several literature sources recommend close surveillance for and an aggressive therapy of SPM. Notwithstanding, their optimal management and follow-up schedule remains to be established.

Keywords::

• Cancer surveillance
• Head and neck cancer
• Metachronous second primary neoplasms
• Second malignancies
• Synchronous neoplasms Abbreviations: EAR = Excess absolute risk; HR = Hazard ratio; HNC = Head and neck cancer; HNSCC = Head and neck squamous cell cancer; HPV = Human papillomavirus; HPSCC = Hypopharyngeal SCC; LSCC = Laryngeal SCC; NPC = Nasopharyngeal cancer; OSCC = Oropharyngeal squamous cell carcinoma; RR = Relative risk; SPLC = Second primary lung cancer; SPM = Second primary malignancy; SCC = Squamous cell cancer; SCCOC = Squamous cell cancer of the oral cavity; SIR = Standardized incidence ratio

Transparency

Declaration of funding

The authors have received no payment in preparation of this manuscript.

Declaration of financial/other relationships

J.A.S.A. and C.A.D. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

CMRO peer reviewers may have received honoraria for their review work. The peer reviewers on this manuscript have disclosed that they have no relevant financial relationships.

Acknowledgments

None.