Rosai-Dorfman's Disease, also known as sinus histiocytosis with massive lymphadenopathy (SHML), is a rare histiocytic proliferative disorder and a distinct clinico-pathological feature of unknown origin. Painless cervical lymphadenopathy is the most common clinical presentation. Different treatment modalities have been tried with variable responses, however, there is no consensus on the best modality of treatment. Here, we present a case report of SHML causing isolated hilar lymphadenopathy with complete remission for more than 6 years, after a short course of high dose steroid (dexamethasone 20 mg daily for 3 days).