When cancer disguises: small-cell lung cancer masquerading as HIV-associated lymphoma in leukaemic phase

In November, 2018, a 62-year-old man with a history of HIV infection and toxoplasma encephalitis started treatment at the Department of Infectious Disease, Yokohama Municipal Citizen's Hospital, Yokohama, Japan. Over 4 years, he continued administration of dolutegravir with emtricitabine and tenofovir alafenamide fumarate, which effectively maintained his plasma HIV-RNA levels below 20 copies per mL. On Dec 21, 2022, he was urgently admitted to our Department of Hematology due to fever, lymphadenopathy, and back pain.