Article continues below advertisementHalsey gave a candid health update ahead of her upcoming tour.The "Without Me" singer - who was diagnosed with lupus and a rare T-cell lymphoproliferative disorder in 2022 - took to TikTok to reveal she recently underwent chemotherapy and described her extensive treatments.Article continues below advertisementSource: @halsey/TikTokHalsey just underwent chemotherapy."Just coming on here to give you guys a speed round of updates," she told fans on Thursday, September 25, with medical tape on her collarbone and chest.