Therapy-related acute myeloid leukaemia and myelodysplastic syndrome in Victoria, Australia 2003-2014

Abstract

Background: The burden of therapy-related acute myeloid leukaemia (tAML)/therapy-related myelodysplastic syndrome (tMDS) in Australia has not been characterised.

Aims: To provide insights into the incidence, associated cancers, latency and survival outcomes of patients with tAML/tMDS in Victoria, Australia, based on a state-wide cancer registry and to assess if these features are different in tAML/tMDS compared with de novo AML/MDS.

Methods: We analysed adults aged ≥20 years at diagnosis of AML/MDS reported to the Victorian Cancer Registry (VCR) between 2003 and 2014.

Results: In total, 73 of 3120 (2.3%) AML cases were classified tAML. tAML patients were younger than non-tAML patients at diagnosis (median age 66 vs 71 years, P = 0.000). Median overall survival was similar (6 months). Median latency to tAML was 82 months, with two incidence peaks at 1-4 and 7-8 years. In total, 59 of 73 patients had recorded cancers, the most frequent being non-Hodgkin lymphoma (NHL, 32.2%) and breast cancer (16.9%). In total, 532 of 3120 (14.1%) additional AML cases had ≥1 prior cancer (confirmation of chemoradiotherapy unavailable). tAML incidence increased (0.0/100 000 persons in 2003, 0.5/100 000 persons in 2014), as did the incidence of non-tAML with previous cancer (0.8/100 000 persons in 2003, 1.1/100 000 persons in 2014). In total, 101 of 4435 (2.3%) MDS cases were classified tMDS. Although tMDS incidence fluctuated (range 0-0.4/100 000 persons/year), the incidence of non-tMDS with prior cancer rose (1.4/100 000 persons in 2003, 1.9/100 000 persons in 2014). Compared to tAML, the tMDS cohort was older (median age 70 vs 66 years, P = 0.007). Median latency to tMDS was 42.5 months. NHL was also the most common cancer preceding tMDS, but the second most common cancer was myeloma (17.8%). In total, 1287 of 5061 (20.3%) non-tMDS patients had a prior cancer.

Conclusions: The burden of tAML/tMDS in Victoria is likely to be underestimated. Linkage between VCR and clinical registries is needed to provide more accurate insights.

Keywords: Australia; survivorship; therapy-related acute myeloid leukaemia; therapy-related myelodysplastic syndrome; therapy-related myeloid neoplasm.