Endocrine Abstracts

Introduction: Cystic masses of neck consist of a variety of pathologic entities. The age of presentation and clinical examination narrow down the differential diagnosis. In adults are considered to be malignancies until proven otherwise (thyroid lesions, salivary gland neoplasms, metastatic squamous cell carcinoma and lymphatic malformations such as the cystic lymphangioma. Ultrasound (US) is often used for initial evaluation. Computed tomography (CT) and MRI provides additional information. FNAC has a supplementary role for confirmation of diagnosis but its accuracy may depend on the experience of the cytopathologist.

Case report: A 41 years old woman presented with a left-side neck mass that had slowly enlarged over the past 6 months with a serious burner. MRI showed a 72*57*47 mm septate mass, with solid and cystic components with contralateral airway displacement and posterior displacement of the carotid. Thyroid US had revealed a normal gland. FNAC was nondiagnostic but the inicial diagnosis was a cystic lymphangioma and the patient was treated with Picibanil (OK-432) without any result. Six months later she underwent surgical excision. The histopathology report came out as Cystic metastatic lymph node from Papillary carcinoma of the thyroid. US demonstrated a poorly defined nodule with micro-calcification in the left lobe of the thyroid. One week later she underwent a total thyroidectomy and bilateral cervical lymphadenectomy. The final diagnosis was a 12 mm Papillary Carcinoma with bilateral metastatic lymph nodes.

Discussion: Metastatic nodes from head-and-neck malignancy, especially papillary carcinoma of the thyroid, are the most common types of nodal metastases presenting as cystic masses in the neck. Eighty percent of the cystic masses in patients over 40 years of age are due to necrotic lymph nodes. On US presence of punctate calcification within the solid component of the cystic node warrants careful search for primary papillary carcinoma in the thyroid gland. In our patient the diagnosis unfortunately was a challenge.

Conclusions: Cystic lesions of the neck are commonly encountered on imaging studies. Clinical presentation along with imaging features as assessed by Doppler US or CT help in accurate diagnosis. These imaging modalities also aid in optimal pre-operative planning. Imaging is essential for accurate diagnosis and pretreatment planning.