Neck Surgery for Non-Well Differentiated Thyroid Malignancies: Variations in Strategy According to Histopathology.

Simple Summary: In non-well differentiated thyroid cancer, the rate of nodal involvement is variable and depends on the histology of the tumor. We aim to highlight the opinions of several experts from different parts of the world on the current management of the less common types of thyroid cancer to provide a consensus on the treatment of regional lymphatics for these entities. The rate of lymph node involvement is variable and depends on the histology of the tumor. Within undifferentiated tumors', there is an established consensus on the treatment of anaplastic carcinoma, medullary carcinoma and poorly differentiated carcinoma of the thyroid. However, treatment of other rarer tumors must be individualized, taking into account both the aggressiveness of the histology and the anatomical distribution of the disease. In general, prophylactic treatment of the neck is not indicated. Lymph node metastases in non-well differentiated thyroid cancer (non-WDTC) are common, both in the central compartment (levels VI and VII) and in the lateral neck (Levels II to V). Nodal metastases negatively affect prognosis and should be treated to maximize locoregional control while minimizing morbidity. In non-WDTC, the rate of nodal involvement is variable and depends on the histology of the tumor. For medullary thyroid carcinomas, poorly differentiated thyroid carcinomas, and anaplastic thyroid carcinomas, the high frequency of lymph node metastases makes central compartment dissection generally necessary. In mucoepidermoid carcinomas, malignant peripheral nerve sheath tumors, sarcomas, and malignant thyroid teratomas or thyroblastomas, central compartment dissection is less often necessary, as clinical lymphnode involvement is less common. We aim to summarize the medical literature and the opinions of several experts from different parts of the world on the current philosophy for managing the neck in less common types of thyroid cancer. [ABSTRACT FROM AUTHOR]