Myelodysplastic syndrome (<scp>MDS</scp>) with isolated trisomy 8: a type of <scp>MDS</scp> frequently associated with myeloproliferative features? A report by the Groupe Francophone des Myélodysplasies

Abstract

Summary Isolated trisomy 8 (+8) is a frequent cytogenetic abnormality in the myelodysplastic syndromes ( MDS ), but its characteristics are poorly reported. We performed a retrospective study of 138 MDS patients with isolated +8, classified or reclassified as MDS (excluding MDS /myeloproliferative neoplasm). Myeloproliferative ( MP ) features were defined by the repeated presence of one of the following: white blood cell count &gt;10 × 10 9 /l, myelemia (presence of circulating immature granulocytes with a predominance of more mature forms) &gt;2%, palpable splenomegaly. Fifty‐four patients (39·1%) had MP features: 28 at diagnosis, 26 were acquired during evolution. MP forms had more EZH 2 (33·3% vs. 12·0% in non‐ MP , P = 0·047), ASXL 1 (66·7% vs. 42·3%, P = 0·048) and STAG 2 mutations (77·8% vs. 21·7%, P = 0·006). Median event‐free survival (EFS) and overall survival ( OS ) were 25 and 27 months for patients with MP features at diagnosis, versus 28 ( P = 0·15) and 39 months ( P = 0·085) for those without MP features, respectively. Among the 57 patients who received hypomethylating agent ( HMA ), OS was lower in MP cases (13 months vs. 23 months in non‐ MP cases, P = 0.02). In conclusion, MP features are frequent in MDS with isolated +8. MP forms had more EZH 2 , ASXL 1 and STAG 2 mutations, responded poorly to HMA , and tended to have poorer survival than non‐ MP forms.