Zuska's disease in a male patient. The critical role of ultrasound imaging in diagnosis and management of this rare entity.

Zuska's disease is a pathologic entity characterized by the formation of subareolar breast abscess caused by the obstruction of lactiferous ducts. Although Zuska's disease is found relatively often in female patients, only 19 male cases have been reported. That makes Zuska's diagnosis challenging in males, leading to significant morbidity and high recurrence rates. Clinical evaluation and imaging techniques, especially ultrasound and mammography, are considered the cornerstones for the diagnosis of Zuska's disease, whereas fine-needle aspiration cytology is necessary in order to exclude malignancy. Multiple treatment approaches have been used including conservative antibiotic therapy, drainage of the abscess and surgical excision of the lactiferous ducts. We present the case of a 57 year old male who was diagnosed with Zuska's disease and treated via ultrasound-guided drainage of the abscess. Having a high level of suspicion, performing appropriate imaging tests and offering definite treatment, is the only way to decrease morbidity and recurrence.

Medullary thyroid carcinoma diagnosed with liquid-based cytology and immunocytochemistry.

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine malignancy that arises from the parafollicular cells (C cells) secreting calcitonin. This study summarizes our experience in the diagnosis of MTC with ultrasound-guided thyroid FNA, subsequently processed with liquid-based cytology (LBC) and immunocytochemistry (ICC). We searched our laboratory archives for thyroid FNA cases with an interpretation of positive or suspicious for MTC, during the period 2004-2018. A total of 20 cases (18 thyroid FNAs; two lymph node FNAs) were selected and included in this study. These displayed high cellularity and a discohesive pattern, with a few loose syncytial groups. There was some variation in the cell size and shape both across and within our cases. Most MTCs (n = 15) exhibited a predominant plasmacytoid/epithelioid cell morphology, whereas five of our cases showed a spindle cell pattern. Of interest, none of eight MTC microcarcinomas (≤1 cm) showed a spindle cell morphology. Amyloid was found in 11/20 cases (55%), while binucleation/multinucleation in 17/20 (85%), and nuclear pseudoinclusions in 3/20 MTC cases (15%). Nuclei exhibited a granular, "salt and pepper" chromatin in all cases. ICC was performed in 18/20 cases (90%). Calcitonin, CEA, TTF1, and Chromogranin were positive wherever applied, whereas thyroglobulin and CK19 were negative. In conclusion, ultrasound-guided thyroid FNA - processed with LBC and ICC - is a reliable modality to detect MTC preoperatively, facilitating the management of such patients.