Progressive nodular histiocytosis (PNH) belongs to an exceedingly rare family of benign proliferative skin disorders known as non-Langerhans cell histiocytoses (NLCHs). Since its initial description as progressive nodular histiocytoma by Taunton et al1 in 1978, there have been only a handful of case reports describing this rare entity. In the past, there has been a great deal of confusion in classifying the various histiocytoses owing to the rarity in which they were encountered as well as to the tremendous overlap, both clinically and histologically, observed between these diseases.2 The lesions encountered in this family of diseases are generally benign; however, in the case reported herein, the involvement of the larynx led to partial airway obstruction, a clinical occurrence previously undescribed (to our knowledge).
Karimi K, Jadidian A, Glavin FL, Chhatwal H, Adelson RT. Laryngeal Involvement in Progressive Nodular HistiocytosisA Case Report. Arch Otolaryngol Head Neck Surg. 2010;136(5):513-516. doi:10.1001/archoto.2010.49