Diagnostic problems among chronic lymphocytic leukemia and other indolent B-cell leukemias in a Japanese population

Perspectives on the Application of Cytogenomic Approaches in Chronic Lymphocytic Leukaemia

Chronic lymphocytic leukaemia (CLL) is a haematological malignancy characterised by the accumulation of monoclonal mature B lymphocytes (positive for CD5+ and CD23+) in peripheral blood, bone marrow, and lymph nodes. Although CLL is reported to be rare in Asian countries compared to Western countries, the disease course is more aggressive in Asian countries than in their Western counterparts. It has been postulated that this is due to genetic variants between populations. Various cytogenomic methods, either of the traditional type (conventional cytogenetics or fluorescence in situ hybridisation (FISH)) or using more advanced technology such as DNA microarrays, next generation sequencing (NGS), or genome wide association studies (GWAS), were used to detect chromosomal aberrations in CLL. Up until now, conventional cytogenetic analysis remained the gold standard in diagnosing chromosomal abnormality in haematological malignancy including CLL, even though it is tedious and time-consuming. In concordance with technological advancement, DNA microarrays are gaining popularity among clinicians as they are faster and better able to accurately diagnose the presence of chromosomal abnormalities. However, every technology has challenges to overcome. In this review, CLL and its genetic abnormalities will be discussed, as well as the application of microarray technology as a diagnostic platform.

Cost of Illness of Japanese Patients with Chronic Lymphocytic Leukemia (CLL), and Budget Impact of the Market Introduction of Ibrutinib

BACKGROUND

Ibrutinib was introduced in Japan in 2016 as a new oral treatment option for patients with relapsed/refractory (RR) chronic lymphocytic leukemia (CLL). There is increasing interest from the Japanese government to assess economic aspects of new medical interventions, especially in the area of oncology.

OBJECTIVE

We describe the treatment patterns of Japanese patients with CLL, estimate the cost of the disease from a health insurance perspective, and predict the budget impact of the introduction of ibrutinib.

METHODS

A budget impact model was set up and populated with data that were collected from a survey of Japanese hematologists (n = 202) and official statistics. Uncertainty was addressed by one-way sensitivity analysis of several model parameters.

RESULTS

Among the 2000 Japanese CLL patients, 42.2% have not yet commenced medical treatment, 29.1% were on a treatment break, and 26.8% received medical treatment, mainly rituximab in combination with either fludarabine or bendamustine. Among the patients under medical treatment, 65.7% were receiving first-line treatment and 34.3% were receiving second-line or later treatment. In Japan, the estimated burden of illness for 2015 was ¥1563 million for RR CLL and ¥5471 million for overall CLL. The expected average budget impact of introducing ibrutinib is ¥3077 million per year for the next 5 years.

CONCLUSION

Due to low disease prevalence, the burden of illness in Japan is low compared with Western countries.