Chapter 084. Head and Neck Cancer (Part 5)

Head and Neck Cancer: Treatment Patients with head and neck cancer can be categorized into three clinical groups: those with localized disease, those with locally or regionally advanced disease, and those with recurrent and/or metastatic disease. Comorbidities associated with tobacco and alcohol abuse can affect treatment outcome and define long-term risks for patients who are cured of their disease.Localized DiseaseNearly one-third of patients have localized disease; that is, T1 or T2 (stage I or stage II) lesions without detectable lymph node involvement or distant metastases. These lesions are treated with curative intent by surgery or radiation therapy. The choice...
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Chapter 084. Head and Neck Cancer (Part 5) Chapter 084. Head and Neck Cancer (Part 5) Head and Neck Cancer: Treatment Patients with head and neck cancer can be categorized into three clinicalgroups: those with localized disease, those with locally or regionally advanceddisease, and those with recurrent and/or metastatic disease. Comorbiditiesassociated with tobacco and alcohol abuse can affect treatment outcome anddefine long-term risks for patients who are cured of their disease. Localized Disease Nearly one-third of patients have localized disease; that is, T1 or T2 (stage Ior stage II) lesions without detectable lymph node involvement or distantmetastases. These lesions are treated with curative intent by surgery or radiationtherapy. The choice of modality differs according to anatomic location andinstitutional expertise. Radiation therapy is often preferred for laryngeal cancer topreserve voice function, and surgery is preferred for small lesions in the oralcavity to avoid the long-term complications of radiation, such as xerostomia anddental decay. Overall 5-year survival is 60–90%. Most recurrences occur withinthe first 2 years following diagnosis and are usually local. Locally or Regionally Advanced Disease Locally or regionally advanced disease—disease with a large primarytumor and/or lymph node metastases—is the stage of presentation for >50% ofpatients. Such patients can also be treated with curative intent, but not withsurgery or radiation therapy alone. Combined modality therapy including surgery,radiation therapy, and chemotherapy is most successful. Concomitantchemotherapy and radiation therapy appears to be the most effective approach. Itcan be administered either as a primary treatment for patients with unresectabledisease, to pursue an organ preserving approach, or in the postoperative setting forintermediate-stage resectable tumors. Induction Chemotherapy In this strategy, patients receive chemotherapy [usually cisplatin andfluorouracil (5-FU)] before surgery and radiation therapy. Most patients whoreceive three cycles show tumor reduction, and the response is clinicallycomplete in up to half. This sequential multimodality therapy allows for organpreservation in patients with laryngeal and hypopharyngeal cancer, and it has beenshown to result in higher cure rates compared with radiotherapy alone when drugcombinations including cisplatin, 5-FU, and a taxane are used. Concomitant Chemoradiotherapy With the concomitant strategy, chemotherapy and radiation therapy aregiven simultaneously rather than sequentially. Because most patients with headand neck cancer develop recurrent disease in the head and neck area, this approachis aimed at killing radiation-resistant cancer cells with chemotherapy. In addition,chemotherapy can enhance cell killing by radiation therapy. Toxicity (especiallymucositis, grade 3 or 4 in 70–80%) is increased with concomitantchemoradiotherapy. However, metaanalyses of randomized trials document animprovement in 5-year survival of 8% with concomitant chemotherapy andradiation therapy. Results seem even more favorable when more activecombinations of drugs are used but have not yet been validated in randomizedtrials. Five-year survival is 34–50%. In addition, concomitantchemoradiotherapy produces better laryngectomy-free survival (organpreservation) than radiation therapy alone in patients with advanced larynx cancer.The use of radiation therapy together with cisplatin has produced markedlyimproved survival in patients with advanced nasopharyngeal cancer. The success of concomitant chemoradiotherapy in patients withunresectable disease has led to the testing of a similar approach in patients withresected disease as a postoperative therapy. Concomitant chemoradiotherapyproduces a significant improvement over postoperative radiation therapy alone forpatients whose tumors demonstrate higher risk features, such as spread beyondnodes, involvement of multiple lymph nodes, or positive margins followingsurgery. Monoclonal antibody to the EGFR (cetuximab) increases survival rateswhen administered during radiotherapy. EGFR blockade results in radiationsensitization and has milder side effects than traditional chemotherapy agents. Theintegration of cetuximab into current standard chemoradiotherapy regimens isunder investigation. Recurrent and/or Metastatic Disease Ten percent of patients present with metastatic disease, and over half ofpatients with locoregionally advanced disease have recurrence, 20% outside thehead and neck region. Patients with recurrent and/or metastatic disease are, withfew exceptio ...