Clinical presentation: A 46-year-old woman was evaluated because of pain in the left side of the neck. A hypoechogenic nodule was detected on ultrasound. Aspiration cytology resulted in C-cell hyperplasia (Dr. Laszlo Vass, MD, PhD, Flor Ferenc Hospital, Kerepestarcsa).

Palpation: no abnormality in the thyroid.

Functional state: euthyroidism with TSH-level 2.26 mIU/L.

Ultrasonography: The right lobe was intact with a small insignificant lesion. There was a hypoechogenic lesion in the ventral part of the left lobe. The lesion had irregular lobulated and spiculated borders.

Images of aspiration cytology are courtesy of Dr.  Laszlo Vass, MD, PhD. Cytological images presented in the second row arose from intraoperative imprint smear.

Blood test for calcitonin: serum-level of calcitonin was 8.78 pM/L (normal value: 0-3.36).

Histopathology: medullary cancer.

Comments.

1. The sonographic pattern is suspicious but not for a medullary but for a papillary cancer.

2. It was a very unusual situation that the pain led to the diagnosis of a medullary carcinoma.

3. Note the presence of two distinct cell populations in the images of aspiration cytology.

4. Regarding the nodule borders, the lesions presented lobulated and spiculated margins.