Spontaneous regression of lung lesions after excision of the submandibular gland in a patient with chronic sclerosing sialadenitis

Chronic sclerosing sialadenitis, which clinically resembles a salivary gland tumor, is considered a salivary gland lesion of the IgG4-related inflammatory disease. Corticosteroids are effective for the treatment of chronic sclerosing sialadenitis, but the natural clinical course of this disease is not fully understood. We report a 67-year-old man with chronic sclerosing sialadenitis who showed lung lesions, which spontaneously regressed without steroid therapy after excision of the submandibular gland. He presented with several weeks' history of continuous swelling in the right submandibular region. Physical examination showed a hard swelling of the right submandibular gland; the cytological finding was Papanicolaou class III. A chest X-ray demonstrated bilateral infiltration of the right middle and left lower lobes. The right submandibular gland was excised under general anesthesia for definite diagnosis, and histopathological examination revealed an IgG4-positive plasmacytic infiltration accompanied by periductal fibrosis and interlobular sclerosis, consistent with chronic sclerosing sialadenitis. Five months after operation, the lung lesions regressed spontaneously.