Rhabdoid cells in the fine needle aspirate of a neck mass in a patient with history of melanoma: Anaplastic thyroid carcinoma

Abstract

A 75-year-old man with a history of malignant melanoma of the upper back, excised with clear margins 10 years previously and staged as pT2aN0M0 and Zenker's presented with complaints of progressive dysphagia with inability to tolerate any oral food intake. Physical exam revealed a large mass in the right neck, which was firm and tender on palpation, and appeared fixed to the underlying structures. CT scan revealed a heterogeneously enhancing mass centered at the right thyroid measuring 5.1 × 4.2 × 5.4 cm, with invasion of the surrounding musculature and the thyroid cartilage. Palpation-guided fine needle aspiration (FNA) was done by the pathologist using 23G needles.The small amount of material obtained was used to make smears that were stained with Diff-Quik or fixed in alcohol for subsequent Papanicolaou staining. Rapid on-site examination was performed and suggested metastatic melanoma. Needle rinses from three passes and an additional dedicated FNA pass were fixed in formalin and used for cell block preparation. The smears were moderately cellular and consisted of very large single cells with eccentric nuclei, in loosely cohesive groups of 5 to 10 cells, or loosely attached to collagenous or cellular fibrous bands formed of bland spindle cells (Figures 1 and 2). The smear background showed RBCs, PMNs, and debris. The tumor cells were rounded or ovoid and measured from 30 × 40 μ to 60 × 70 μ. Most of their cytoplasm was occupied by a round 20 to 50 μ diameter homogenous dark structure staining blue with Diff-Quik (Figure 3) and green with Papanicolaou (Figure 4), pushing the nucleus to the side and conferring the tumor cells a "rhabdoid" appearance. Occasional cells showed phagocytosis of red blood cells, neutrophils, or lymphocytes. The majority of tumor cells had a single large eccentrically located ovoid hyperchromatic nucleus measuring 25 to 40 μ; and contained a single large rounded or elongated 5 to 7 μ nucleolus best visualized in Papanicolaou-stained smears. Occasional very large binucleated cells with mirror-image eccentric nuclei were also seen. Mitoses were readily identified. The cell block contained rare single cells with similar features ( Figure 5A,B). Immunostains revealed the tumor cells were negative for S-100, but were strongly positive for CKAE1/AE3 and PAX8 ( Figure 5C,D). This immunoprofile excluded a metastatic melanoma, which was originally favored based on the cytomorphology and the patient's history, and helped establish the diagnosis of anaplastic (undifferentiated) thyroid carcinoma with rhabdoid features. Chemotherapy was planned, but the patient unfortunately expired within a month of the diagnosis, before chemotherapy could be instituted.Anaplastic thyroid carcinoma (ATC) is a rare but extremely aggressive malignancy with a survival rate of only 10% at 2 years 1 ; although it comprises only 1% to 2% of thyroid cancers, it is responsible for up to 50% of all thyroid cancer-related deaths. 2 Clinically, it presents in older patients (median age 70 years) as a rapidly expanding larg...

Cetuximab-Conjugated Perfluorohexane/Gold Nanoparticles for Low Intensity Focused Ultrasound Diagnosis Ablation of Thyroid Cancer Treatment

“…ATC'ssevere prognosis is due to the rapid progression of tumors beforediagnosis. Current treatment is based on different combinations ofchemotherapy, and exterior ray radiation has been unsuccessful inenhancing survival, resulting in an average survival rate of 4 to 6months and less than 20% survival rate in 12 months [5][6][7][8].Therefore, there are convincing arguments for the development of anew theranostic approach for initial nding and e cient ATCtreatment [9][10][11].…”

Cetuximab-conjugated perfluorohexane/gold nanoparticles for low intensity focused ultrasound diagnosis ablation of thyroid cancer treatment

“…The severe prognosis that accompanies ATC is due to the rapid progression of tumors before diagnosis. Current treatment is based on different combinations of chemotherapy and exterior beam radiation, which have been unsuccessful in improving survival, where average survival rates are 4 to 6 months with less than 20% survival in 12 months [5][6][7][8]. Therefore, new theranostic approaches for initial detection and efficient ATC treatment are needed [9][10][11].…”