MTC does not concentrate RAI and responds less to EBRT than WDTC. The clinical course of patients with metastatic MTC is highly variable, ranging from indolent disease with survival for decades to aggressive, rapidly fatal outcomes [7]. Patients with advanced disease may suffer from flushing and diarrhea related to tumor secretion of bioactive substances (calcitonin and others). Debulking the tumor burden often controls these symptoms [7]. Table 21.2 depicts the role of the different treatment options available in MTC.

ATC is one of the most aggressive solid neoplasms with a median survival of 6 months after diagnosis [9]. It most commonly presents as a large, firm thyroid mass causing hoarseness, vocal cord paralysis, dysphagia, cervical pain, and dyspnea. Diagnosis is available via fine-needle aspiration or core biopsy and, if necessary, open surgical biopsy [10]. Routine intraoperative frozen sections are not recommended but may be helpful either to ensure adequate sampling or to confirm diagnosis if it will change surgical procedure [10]. Initial staging includes appropriate locoregional imaging with computerized tomography (CT) scan or magnetic resonance imaging (MRI) as well as distant disease assessment with positron emission tomography (PET)-CT scan or, if not available, cross-sectional imaging of the brain, chest, abdomen, and pelvis [10]. Direct laryngoscopy will assess vocal cord mobility and for any disease extension into the laryngotracheal area [10]. Most cancer-related deaths are due to rapid locoregional growth so therapeutic efforts should be concentrated here. A multidisciplinary team with therapeutic decisions individualized based on patient and disease factors is needed. These patients are often best managed by multimodal therapy, including surgery and EBRT ± chemotherapy [10]. Due to its poor prognosis, aggressive approaches in metastatic ATC should be used sparingly. See Fig. 21.1.

Complete surgical excision, not including major structures such as the larynx and esophagus, should be performed [10]. Unfortunately, this is rarely possible. There is currently no known survival advantage of achieving microscopically negative margins compared to grossly negative margins. Therefore, an en bloc resection should be considered whenever all gross disease can be resected, but tumor debulking with grossly positive margins should not be attempted [10]. The definition of “unresectable” may vary among institutions, depending on tumor extent and expertise. In cases of inoperability, neoadjuvant EBRT and/or chemotherapy should be considered, possibly rendering the tumor suitable for surgery [10]. As there is a high risk of relapse after response to EBRT ± chemotherapy, surgery should be performed when feasible in these cases.

Tracheostomy for airway compromise is technically challenging and has a high rate of healing complications, which can delay EBRT. It should be considered in cases of impending airway obstruction, not prophylactically [10]. If performed, this must be undertaken in the operating room under general anesthesia and should not be performed in the emergency department or on the ward [10]. Pretracheal tumor debulking or isthmusectomy may be necessary. Most patients requiring a tracheostomy have aggressive disease with a poor prognosis. It may relieve airway distress but provides minimal prolongation of life with potential prolonged suffering, so it should be a fully informed decision made by the patient and their healthcare team.

Table 21.3 summarizes the role of the different adjuvant and palliative treatment options available for ATC.