Diagnostic immunophenotype of acute promyelocytic leukemia before and early during therapy with all-trans retinoic acid

Pedro Horna, Ling Zhang, Eduardo M. Sotomayor, Jeffrey E. Lancet, Lynn C. Moscinski

Research output: Contribution to journalArticle

4 Scopus citations


Objectives: To study the immunophenotypic changes of acute promyelocytic leukemia (APL) in patients who recently received all-trans retinoic acid (ATRA) and to assess the diagnostic utility of flow cytometry in this setting. Methods: Flow cytometry was performed on 29 newly diagnosed APLs and 93 other acute myeloid leukemias, including 25 HLA-DR- or CD34- cases. Clinical notes from referring institutions were reviewed to assess for recent ATRA administration. Results: Recent ATRA therapy was documented in 17 (59%) of 29 patients with APL. The main features of untreated APL were preserved with ATRA therapy, including CD34- (83% vs 82%), HLA-DR- (83% vs 100%), and CD117+ (100% vs 77%). CD11b and CD11c were negative in all untreated APLs but positive in 76% and 88% of ATRA-treated APLs, respectively. Optimal diagnostic criteria for untreated APL (CD34- or HLA-DR- and CD11b- and CD11c-) showed 100% sensitivity and 98% specificity but were not useful after ATRA administration. The best interpretative approach to ATRA-treated APL (CD34- or HLA-DR-) showed 100% sensitivity but limited specificity (73%). Conclusions: Information about recent ATRA administration is critical for adequate interpretation of the flow cytometric findings in patients with suspected APL.

Original languageEnglish (US)
Pages (from-to)546-552
Number of pages7
JournalAmerican journal of clinical pathology
Issue number4
StatePublished - Oct 1 2014
Externally publishedYes



  • Acute promyelocytic leukemia
  • All-trans retinoic acid
  • Flow cytometry

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

Cite this