title: Clinical significance of newly emerged isolated del(20q) in patients following cytotoxic therapies.
abstract: Deletion 20q is a common chromosomal abnormality in myeloid neoplasms. Detection of del(20q) in patients following cytotoxic therapies raises concerns for an emerging therapy-related myeloid neoplasm. In this study, we identified 92 patients who acquired isolated del(20q) in their bone marrow following cytotoxic therapies for malignant neoplasms. Seventy-six patients showed interstitial and sixteen patients showed terminal 20q deletion. The median interval from prior cytotoxic therapies to detection of del(20q) was 58 months (range, 5-213 months). With a median follow-up of 23 months (range, 1-183 months), 21 (23%) patients developed therapy-related myeloid neoplasm and 71 (77%) patients did not. In patients who developed therapy-related myeloid neoplasm, del(20q) presented in a higher percentage of metaphases (60 vs 25%, P<0.0001); persisted for a longer period of time (24 vs 10 months, P=0.0487); and was more often a terminal deletion (33 vs 13%, P=0.0006) compared with patients who did not develop therapy-related myeloid neoplasm. Clonal evolution was only detected in patients with therapy-related myeloid neoplasm (4 patients, 19%). We conclude that del(20q) emerging after cytotoxic therapy represents an innocuous finding in more than two-thirds of patients. In patients who develop a therapy-related myeloid neoplasm, del(20q) often involves a higher percentage of metaphases, persists longer and more frequently is a terminal rather than an interstitial deletion.
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: C Cameron
authors.initials: CC
authors.lastname: Yin
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Peng
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Rashmi
authors.initials: R
authors.lastname: Kanagal-Shamanna
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Tariq
authors.initials: T
authors.lastname: Muzzafar
authors.affiliation: Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Courtney
authors.initials: C
authors.lastname: DiNardo
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Khoury
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Shaoying
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: L Jeffrey
authors.initials: LJ
authors.lastname: Medeiros
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Sa A
authors.initials: SA
authors.lastname: Wang
authors.affiliation: Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Guilin
authors.initials: G
authors.lastname: Tang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects*; D001856:Bone Marrow Examination; D059248:Chemoradiotherapy / Q000009:adverse effects* / Q000401:mortality; D002869:Chromosome Aberrations / Q000139:chemically induced*; D002872:Chromosome Deletion; D002890:Chromosomes, Human, Pair 20 / Q000187:drug effects* / Q000528:radiation effects*; D060965:Clonal Evolution; D016208:Databases, Factual; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D053208:Kaplan-Meier Estimate; D008297:Male; D008677:Metaphase; D008875:Middle Aged; D009381:Neoplasms, Radiation-Induced / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D016609:Neoplasms, Second Primary / Q000139:chemically induced* / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D011878:Radiotherapy / Q000009:adverse effects; D012189:Retrospective Studies; D012307:Risk Factors; D033581:Stem Cell Transplantation; D013781:Texas; D013997:Time Factors