The Evolution of Care of Cancers of the Head and Neck Region: State of the Science in 2020

Abstract

Cancers that arise in the head and neck region are comprised of a heterogeneous group of malignancies that include carcinogen- and human papillomavirus (HPV)-driven mucosal squamous cell carcinoma as well as skin cancers such as cutaneous squamous cell carcinoma, basal cell carcinoma, melanoma, and Merkel cell carcinoma. These malignancies develop in critical areas for eating, talking, and breathing and are associated with substantial morbidity and mortality despite advances in treatment. Understanding of advances in the management of these various cancers is important for all multidisciplinary providers who care for patients across the cancer care continuum. Additionally, the recent Coronavirus Disease 2019 (COVID-19) pandemic has necessitated adaptations to head and neck cancer care to accommodate the mitigation of COVID-19 risk and ensure timely treatment. This review explores advances in diagnostic criteria, prognostic factors, and management for subsites including head and neck squamous cell carcinoma and the various forms of skin cancer (basal cell carcinoma, cutaneous squamous cell carcinoma, Merkel cell carcinoma, and melanoma). Then, this review summarizes emerging developments in immunotherapy, radiation therapy, cancer survivorship, and the delivery of care during the COVID-19 era.

Keywords: COVID-19; head and neck cancer; head and neck squamous cell carcinoma; salivary gland cancer; skin cancer; thyroid cancer.

Figure 1

Measuring depth of invasion in an exophytic (A) versus ulcerative (B) tumor. Even though the exophytic tumor is thicker, the ulcerative tumor has a greater DOI below the normal basement membrane level. Abbreviations: Basement membrane (BM), Depth of invasion (DOI), Normal Epithelial Surface Level (E), Tumor Thickness (TT).

Figure 2

Systemic treatment options for unresectable or metastatic melanoma. Abbreviations: BRAF positive for mutation (BRAF+), BRAF negative for mutant type (BRAF−), immunohistochemistry (IHC), lactate dehydrogenase serum level (LDH), mitogen-activated protein kinase (MEK), next-generation sequencing (NGS), polymerase chain reaction (PCR). * Areas under active investigation include, but are not limited to different immunotherapy and BRAF/MEK inhibition regimens, or c-kit targeted therapies. ^a FDA-approved for advanced melanoma with BRAF V600E or V600K mutation.

Figure 3

Immunotherapies for head and neck cancers. Checkpoint blockade: (A) Programmed cell death protein 1 ligand (PD-1) or PD-L1 blockade has the potential to improve T cell activation after antigen-presenting cells present tumor antigens to T cells or (B) may promote T cell effector function directly at the tumor. Oncolytic viruses: Infection of tumor cells with oncolytic viruses promotes tumor death (C) by the direct killing of tumor cells, or (D) by the release of tumor neoantigens and augmenting immune responses to tumor. Adoptive T cell therapy: Tumors are targeted with a patient’s own T cells, which are either (E) expanded directly from the tumor or (F) engineered with TCRs responding to tumor antigens. Abbreviations: Major Histocompatibility Complex (MHC); T cell receptor (TCR).