Rebound lymphocytosis in a patient with chronic lymphocytic leukemia after cessation of a CDK 4/6 inhibitor for concomitant breast cancer. Issue 10 (8th July 2020)

• Record Type: Journal Article
• Authors: Doucette, Kimberley; Lai, Catherine; Pohlmann, Paula R,
• Is Part Of: Breast journal. Volume 26:Issue 10(2020)
• Page Start: 2031
• Page End: 2033
• Publication Date: 2020-07-08
• Subjects: carcinoma -- ductal -- breast -- leukemia -- lymphocytic -- chronic -- B cell -- lymphocytosis -- palbociclib; Breast -- Diseases -- Periodicals; Breast -- Cancer -- Periodicals; 618.19
• DOI: 10.1111/tbj.13955
• Languages: English
• ISSNs: 1075-122X

Abstract

Abstract: Herein, we present the case of a female with co‐occurring chronic lymphocytic leukemia (CLL) and metastatic ER/PR‐positive breast cancer, who when taken off palbociclib for severe neutropenia and infectious complications, experienced rebound lymphocytosis. Though this was ultimately a benign clinical outcome, it exemplifies how CDK4/6 inhibitors induce a cell cycle arrest by decreasing the proliferation of hematopoietic stem cells (HSC), in this case CLL cells, with recovery of counts once drug is stopped.