Radiotherapy for head and neck cancer

Head and neck cancer is a staggering public health problem. Its relative infrequency in North America (estimated at 40,000-50,000 cases per year in the United States) belies its distinction as the fifth most common cause of cancer death worldwide [1]. Oral cavity cancer is the most frequent cancer killer in India and is the second most frequent in France, because of a prevalent use of cigarettes, smokeless tobacco products, and alcohol. Beyond simple numbers, the disease extracts a heavy personal toll. The consequences of head and neck cancer degrade the most elemental of human functions, including speech, eating, sight, hearing, and facial appearance. Head and neck cancer defies simple management. It encompasses a broad spectrum of diseases that behave in varied ways based on seemingly subtle differences in anatomic location and histology. It most commonly presents as squamous cell carcinoma emanating from the mucosal lining of the upper aerodigestive tract, most notably that of die oral cavity, larynx, and pharynx. These cancers are the focus of this article. The term also includes cancers of regional skin (in fact, the most common of head and neck cancer sites by raw incidence), salivary glands, thyroid gland, paranasal sinuses, periorbital structures, peripheral nerves, and connective tissues. Radiotherapy and surgery, either alone or in combination, are used to address locoregional disease. Systemic therapies historically reserved for treatment of metastatic disease are now used at all points of therapy because of demonstrated efficacy and tolerability. Treatment remains morbid and incompletely effective, however. Specialized, supportive rehabilitative care is gaining recognition but remains understudied. That said, real progress has been made during the past decade. The understanding of how best to deliver radiation, either alone or in combination with other modalities, continues to mature. Technical delivery of radiation is evolving rapidly, vastly improving treatment precision. Complementary achievements in head and neck surgical technique, chemotherapy, and biologic therapy have opened new function-sparing treatment pathways for patients once faced only with debilitating surgery. The end result has been a steady, significant improvement in curative and recuperative outcomes for a cancer long fraught with failure. This article focuses on radiotherapy's role in this progress.