Abstract

INTRODUCTION

Oncology centers like Tata Memorial Hospital (TMH) see a large number of patients with CML every year. We have actually witnessed the revolutionary change in the treatment of CML from parenteral injections to simple oral medication that translated into dramatically improved survival as well as quality-of-life for these patients. With the assistance of patient assistance programs thousands of lives have been saved without the need for expensive, difficult and toxic treatment with interferon, cytarabine or Bone marrow transplantation. The introduction of imatinib (IM) and other oral tyrosine kinase inhibitors (TKIs) have improved understanding of the disease and led to change in the parameters of documenting disease response. [1,2] Complete blood counts are no longer accepted as response indicators by themselves; the value of cytogenetic and molecular response evaluation as well as mutation analysis is now well-established. [3,4] In this retrospective analysis, we document the outcome in one of the largest group of CML patients treated in India.

PATIENTS AND METHODS

The data was collected retrospectively from year January 2002 to January 2008. The files and the electronic medical record of all patients diagnosed with CML at the hospital provided information pertaining to age, sex, date of diagnosis, address, phone number, blood counts, bone marrow reports, spleen size at diagnosis, cytogenetic and molecular reports brand and dose of IM, change in dose, any primary or secondary resistance; tolerability, the side-effects of IM and outcome. Data was also obtained from records of patient assistance programs.

RESULTS

A total 972 patients of CML were registered between January 2002 and January 2008 with median age of 36 years (12-81 years). This included 730 (75%) males and 242 (25%) females, giving an M: F ratio of 3:1. Of these, 815 were evaluated at TMH at baseline. Their characteristics at diagnosis are shown in Table 1.

Table 1

DISCUSSION

Targeted therapy in the form of TKIs has completely changed the management and the outcome of CML. In this study, we made the comparisons between the groups like brand of IM, presence or absence of clonal evolution; time to start IM, continuity in taking IM. As this is retrospective data, it has its limitations. Nevertheless, it gives us few important points to ponder. Foremost, post-IM the OAS of our population is comparable with western population. We had OAS survival of 86% at 5 years, which was comparable with the landmark study, the international randomized study of interferon versus STI571 (IRIS) trial showing 89% OAS at 5 years [5] Second, our data showed that patients presenting in early CP do better when compared to patients in late CP. Again this finding is well documented in the literature. In a phase II trial by Gambacorti et al., they found patients in late CP had CCyR of 55% compared to 87% in early CP, as reported in IRIS trial. [6] Third, CCyR also depends on the continuation of IM intake. This data emphasizes that to have best results, it is important to minimize the gaps in IM intake and this can be achieved only by aggressive patient counseling and by optimizing the drug dosage on regular basis. The importance of IM adherence has been well-documented in ADAGIO study and data reconfirms it. [7] Fourth, the most important conclusion we can make in this study is that there is not much difference in the outcome of patients taking different brands of IM and generic can be used where original drug is not available to the patient.

Footnotes