Bone marrow Ki‐67 index is of prognostic value in newly diagnosed multiple myeloma

• Published in: European journal of haematology 2023-09, Vol.111 (3), p.373-381
• Main Authors: Atrash, Shebli, Robinson, Myra, Taneja, Alankrita, Paul, Barry, Cassetta, Kristen, Ndiaye, Ami, Varga, Cindy, Block, Jared, Lipford, Edward H., Smith, Elton T., McCall, Chad M., Thurston, Virginia, Foureau, David, Usmani, Saad Z., Voorhees, Peter M., Bhutani, Manisha
• Format: Article
• Language: English
• Subjects: biomarker; Biopsy; Bone marrow; Immunohistochemistry; Ki‐67; Malignancy; Multiple myeloma; newly diagnosed multiple myeloma; prognosis; Risk factors; Survival
• ISSN: 0902-4441; 1600-0609
• DOI: 10.1111/ejh.14016

Background Ki‐67 is an index of proliferative activity and is an established predictive and prognostic marker in multiple malignancies. However, its prognostic relevance in multiple myeloma (MM) is unclear. We investigated the relationship between Ki‐67 expression and survival outcomes in MM in the era of novel therapies. Methods We interrogated our database to identify patients with MM, newly diagnosed between July 1, 2013 and December 31, 2020, with Ki‐67 expression assessed by immunohistochemistry (IHC) on bone marrow biopsies. Using an established threshold of 5% we defined Ki‐67low (≤5%) and Ki‐67high (>5%) subgroups for association with progression‐free survival (PFS) and overall survival (OS). Results Of 167 patients included: 53 (31.7%) had Ki‐67high and 114 had Ki‐67low. More patients with R‐ISS 3 had Ki‐67high (22.2% vs. 9.7%). The gain of 1q21 was overrepresented in the Ki‐67high group (28% vs. 8%). Median PFS in the Ki‐67low group was 3.1 years, and in the Ki‐67high group 1.6 years (log‐rank p