Hypercalcemia with invasive pulmonary papillomatosis and microinvasive squamous carcinoma

Juvenile respiratory papillomatosis is a rare pediatric disease in which benign papillomata develop in the respiratory tract, most commonly involving the larynx and tracheobronchial tree.  Invasive pulmonary papillomatosis is an aggressive form in which the papillomata extend into the lung parenchyma.  We report a case of a 22-year-old man with a long-standing juvenile respiratory tract papillomatosis, initially diagnosed at age 2, who subsequently developed invasive pulmonary papillomatosis and underwent partial surgical resection for his pulmonary disease.  Hypercalcemia complicated the patient’s final hospitalizations. HPV typing performed on a laryngeal papilloma was positive for HPV 6/11.  The lobectomy specimen revealed malignant transformation of invasive pulmonary papillomatosis characterized by the presence of microinvasive nests of squamous carcinoma. Immunohistochemical stain for parathyroid hormone on the invasive component was negative. Eventually, the patient succumbed to his disease and while the family refused post-mortem examination, Positron Emission Tomography (PET) performed during the patient’s terminal course suggested the possibility of metastasis to liver and periaortic lymph nodes. There was no evidence of bony metastasis.